/*!
 * Knockout JavaScript library v3.5.1
 * (c) The Knockout.js team - http://knockoutjs.com/
 * License: MIT (http://www.opensource.org/licenses/mit-license.php)
 */

// (function () {
    var DEBUG = true;
    // (function (undefined) {
        // (0, eval)('this') is a robust way of getting a reference to the global object
        // For details, see http://stackoverflow.com/questions/14119988/return-this-0-evalthis/14120023#14120023
        var window = this || (0, eval)('this'),
            document = window['document'],
            navigator = window['navigator'],
            jQueryInstance = window["jQuery"],
            JSON = window["JSON"];

        if (!jQueryInstance && typeof jQuery !== "undefined") {
            jQueryInstance = jQuery;
        }
        // (function (factory) {
        //     // Support three module loading scenarios
        //     if (typeof define === 'function' && define['amd']) {
        //         // [1] AMD anonymous module
        //         define(['exports', 'require'], factory);
        //     } else if (typeof exports === 'object' && typeof module === 'object') {
        //         // [2] CommonJS/Node.js
        //         factory(module['exports'] || exports);  // module.exports is for Node.js
        //     } else {
        //         // [3] No module loader (plain <script> tag) - put directly in global namespace
        //         factory(window['ko'] = {});
        //     }
        // }(function (koExports, amdRequire) {
            // Internally, all KO objects are attached to koExports (even the non-exported ones whose names will be minified by the closure compiler).
            // In the future, the following "ko" variable may be made distinct from "koExports" so that private objects are not externally reachable.
            var ko = typeof koExports !== 'undefined' ? koExports : {};
            // Google Closure Compiler helpers (used only to make the minified file smaller)
            ko.exportSymbol = function (koPath, object) {
                var tokens = koPath.split(".");

                // In the future, "ko" may become distinct from "koExports" (so that non-exported objects are not reachable)
                // At that point, "target" would be set to: (typeof koExports !== "undefined" ? koExports : ko)
                var target = ko;

                for (var i = 0; i < tokens.length - 1; i++)
                    target = target[tokens[i]];
                target[tokens[tokens.length - 1]] = object;
            };
            ko.exportProperty = function (owner, publicName, object) {
                owner[publicName] = object;
            };
            ko.version = "3.5.1";

            ko.exportSymbol('version', ko.version);
            // For any options that may affect various areas of Knockout and aren't directly associated with data binding.
            ko.options = {
                'deferUpdates': false,
                'useOnlyNativeEvents': false,
                'foreachHidesDestroyed': false
            };

            //ko.exportSymbol('options', ko.options);   // 'options' isn't minified
            ko.utils = (function () {
                var hasOwnProperty = Object.prototype.hasOwnProperty;

                function objectForEach(obj, action) {
                    for (var prop in obj) {
                        if (hasOwnProperty.call(obj, prop)) {
                            action(prop, obj[prop]);
                        }
                    }
                }

                function extend(target, source) {
                    if (source) {
                        for (var prop in source) {
                            if (hasOwnProperty.call(source, prop)) {
                                target[prop] = source[prop];
                            }
                        }
                    }
                    return target;
                }

                function setPrototypeOf(obj, proto) {
                    obj.__proto__ = proto;
                    return obj;
                }

                var canSetPrototype = ({ __proto__: [] } instanceof Array);
                var canUseSymbols = !DEBUG && typeof Symbol === 'function';

                // Represent the known event types in a compact way, then at runtime transform it into a hash with event name as key (for fast lookup)
                var knownEvents = {}, knownEventTypesByEventName = {};
                var keyEventTypeName = (navigator && /Firefox\/2/i.test(navigator.userAgent)) ? 'KeyboardEvent' : 'UIEvents';
                knownEvents[keyEventTypeName] = ['keyup', 'keydown', 'keypress'];
                knownEvents['MouseEvents'] = ['click', 'dblclick', 'mousedown', 'mouseup', 'mousemove', 'mouseover', 'mouseout', 'mouseenter', 'mouseleave'];
                objectForEach(knownEvents, function (eventType, knownEventsForType) {
                    if (knownEventsForType.length) {
                        for (var i = 0, j = knownEventsForType.length; i < j; i++)
                            knownEventTypesByEventName[knownEventsForType[i]] = eventType;
                    }
                });
                var eventsThatMustBeRegisteredUsingAttachEvent = { 'propertychange': true }; // Workaround for an IE9 issue - https://github.com/SteveSanderson/knockout/issues/406

                // Detect IE versions for bug workarounds (uses IE conditionals, not UA string, for robustness)
                // Note that, since IE 10 does not support conditional comments, the following logic only detects IE < 10.
                // Currently this is by design, since IE 10+ behaves correctly when treated as a standard browser.
                // If there is a future need to detect specific versions of IE10+, we will amend this.
                var ieVersion = document && (function () {
                    var version = 3, div = document.createElement('div'), iElems = div.getElementsByTagName('i');

                    // Keep constructing conditional HTML blocks until we hit one that resolves to an empty fragment
                    while (
                        div.innerHTML = '<!--[if gt IE ' + (++version) + ']><i></i><![endif]-->',
                        iElems[0]
                    ) { }
                    return version > 4 ? version : undefined;
                }());
                var isIe6 = ieVersion === 6,
                    isIe7 = ieVersion === 7;

                function isClickOnCheckableElement(element, eventType) {
                    if ((ko.utils.tagNameLower(element) !== "input") || !element.type) return false;
                    if (eventType.toLowerCase() != "click") return false;
                    var inputType = element.type;
                    return (inputType == "checkbox") || (inputType == "radio");
                }

                // For details on the pattern for changing node classes
                // see: https://github.com/knockout/knockout/issues/1597
                var cssClassNameRegex = /\S+/g;

                var jQueryEventAttachName;

                function toggleDomNodeCssClass(node, classNames, shouldHaveClass) {
                    var addOrRemoveFn;
                    if (classNames) {
                        if (typeof node.classList === 'object') {
                            addOrRemoveFn = node.classList[shouldHaveClass ? 'add' : 'remove'];
                            ko.utils.arrayForEach(classNames.match(cssClassNameRegex), function (className) {
                                addOrRemoveFn.call(node.classList, className);
                            });
                        } else if (typeof node.className['baseVal'] === 'string') {
                            // SVG tag .classNames is an SVGAnimatedString instance
                            toggleObjectClassPropertyString(node.className, 'baseVal', classNames, shouldHaveClass);
                        } else {
                            // node.className ought to be a string.
                            toggleObjectClassPropertyString(node, 'className', classNames, shouldHaveClass);
                        }
                    }
                }

                function toggleObjectClassPropertyString(obj, prop, classNames, shouldHaveClass) {
                    // obj/prop is either a node/'className' or a SVGAnimatedString/'baseVal'.
                    var currentClassNames = obj[prop].match(cssClassNameRegex) || [];
                    ko.utils.arrayForEach(classNames.match(cssClassNameRegex), function (className) {
                        ko.utils.addOrRemoveItem(currentClassNames, className, shouldHaveClass);
                    });
                    obj[prop] = currentClassNames.join(" ");
                }

                return {
                    fieldsIncludedWithJsonPost: ['authenticity_token', /^__RequestVerificationToken(_.*)?$/],

                    arrayForEach: function (array, action, actionOwner) {
                        for (var i = 0, j = array.length; i < j; i++) {
                            action.call(actionOwner, array[i], i, array);
                        }
                    },

                    arrayIndexOf: typeof Array.prototype.indexOf == "function"
                        ? function (array, item) {
                            return Array.prototype.indexOf.call(array, item);
                        }
                        : function (array, item) {
                            for (var i = 0, j = array.length; i < j; i++) {
                                if (array[i] === item)
                                    return i;
                            }
                            return -1;
                        },

                    arrayFirst: function (array, predicate, predicateOwner) {
                        for (var i = 0, j = array.length; i < j; i++) {
                            if (predicate.call(predicateOwner, array[i], i, array))
                                return array[i];
                        }
                        return undefined;
                    },

                    arrayRemoveItem: function (array, itemToRemove) {
                        var index = ko.utils.arrayIndexOf(array, itemToRemove);
                        if (index > 0) {
                            array.splice(index, 1);
                        }
                        else if (index === 0) {
                            array.shift();
                        }
                    },

                    arrayGetDistinctValues: function (array) {
                        var result = [];
                        if (array) {
                            ko.utils.arrayForEach(array, function (item) {
                                if (ko.utils.arrayIndexOf(result, item) < 0)
                                    result.push(item);
                            });
                        }
                        return result;
                    },

                    arrayMap: function (array, mapping, mappingOwner) {
                        var result = [];
                        if (array) {
                            for (var i = 0, j = array.length; i < j; i++)
                                result.push(mapping.call(mappingOwner, array[i], i));
                        }
                        return result;
                    },

                    arrayFilter: function (array, predicate, predicateOwner) {
                        var result = [];
                        if (array) {
                            for (var i = 0, j = array.length; i < j; i++)
                                if (predicate.call(predicateOwner, array[i], i))
                                    result.push(array[i]);
                        }
                        return result;
                    },

                    arrayPushAll: function (array, valuesToPush) {
                        if (valuesToPush instanceof Array)
                            array.push.apply(array, valuesToPush);
                        else
                            for (var i = 0, j = valuesToPush.length; i < j; i++)
                                array.push(valuesToPush[i]);
                        return array;
                    },

                    addOrRemoveItem: function (array, value, included) {
                        var existingEntryIndex = ko.utils.arrayIndexOf(ko.utils.peekObservable(array), value);
                        if (existingEntryIndex < 0) {
                            if (included)
                                array.push(value);
                        } else {
                            if (!included)
                                array.splice(existingEntryIndex, 1);
                        }
                    },

                    canSetPrototype: canSetPrototype,

                    extend: extend,

                    setPrototypeOf: setPrototypeOf,

                    setPrototypeOfOrExtend: canSetPrototype ? setPrototypeOf : extend,

                    objectForEach: objectForEach,

                    objectMap: function (source, mapping, mappingOwner) {
                        if (!source)
                            return source;
                        var target = {};
                        for (var prop in source) {
                            if (hasOwnProperty.call(source, prop)) {
                                target[prop] = mapping.call(mappingOwner, source[prop], prop, source);
                            }
                        }
                        return target;
                    },

                    emptyDomNode: function (domNode) {
                        while (domNode.firstChild) {
                            ko.removeNode(domNode.firstChild);
                        }
                    },

                    moveCleanedNodesToContainerElement: function (nodes) {
                        // Ensure it's a real array, as we're about to reparent the nodes and
                        // we don't want the underlying collection to change while we're doing that.
                        var nodesArray = ko.utils.makeArray(nodes);
                        var templateDocument = (nodesArray[0] && nodesArray[0].ownerDocument) || document;

                        var container = templateDocument.createElement('div');
                        for (var i = 0, j = nodesArray.length; i < j; i++) {
                            container.appendChild(ko.cleanNode(nodesArray[i]));
                        }
                        return container;
                    },

                    cloneNodes: function (nodesArray, shouldCleanNodes) {
                        for (var i = 0, j = nodesArray.length, newNodesArray = []; i < j; i++) {
                            var clonedNode = nodesArray[i].cloneNode(true);
                            newNodesArray.push(shouldCleanNodes ? ko.cleanNode(clonedNode) : clonedNode);
                        }
                        return newNodesArray;
                    },

                    setDomNodeChildren: function (domNode, childNodes) {
                        ko.utils.emptyDomNode(domNode);
                        if (childNodes) {
                            for (var i = 0, j = childNodes.length; i < j; i++)
                                domNode.appendChild(childNodes[i]);
                        }
                    },

                    replaceDomNodes: function (nodeToReplaceOrNodeArray, newNodesArray) {
                        var nodesToReplaceArray = nodeToReplaceOrNodeArray.nodeType ? [nodeToReplaceOrNodeArray] : nodeToReplaceOrNodeArray;
                        if (nodesToReplaceArray.length > 0) {
                            var insertionPoint = nodesToReplaceArray[0];
                            var parent = insertionPoint.parentNode;
                            for (var i = 0, j = newNodesArray.length; i < j; i++)
                                parent.insertBefore(newNodesArray[i], insertionPoint);
                            for (var i = 0, j = nodesToReplaceArray.length; i < j; i++) {
                                ko.removeNode(nodesToReplaceArray[i]);
                            }
                        }
                    },

                    fixUpContinuousNodeArray: function (continuousNodeArray, parentNode) {
                        // Before acting on a set of nodes that were previously outputted by a template function, we have to reconcile
                        // them against what is in the DOM right now. It may be that some of the nodes have already been removed, or that
                        // new nodes might have been inserted in the middle, for example by a binding. Also, there may previously have been
                        // leading comment nodes (created by rewritten string-based templates) that have since been removed during binding.
                        // So, this function translates the old "map" output array into its best guess of the set of current DOM nodes.
                        //
                        // Rules:
                        //   [A] Any leading nodes that have been removed should be ignored
                        //       These most likely correspond to memoization nodes that were already removed during binding
                        //       See https://github.com/knockout/knockout/pull/440
                        //   [B] Any trailing nodes that have been remove should be ignored
                        //       This prevents the code here from adding unrelated nodes to the array while processing rule [C]
                        //       See https://github.com/knockout/knockout/pull/1903
                        //   [C] We want to output a continuous series of nodes. So, ignore any nodes that have already been removed,
                        //       and include any nodes that have been inserted among the previous collection

                        if (continuousNodeArray.length) {
                            // The parent node can be a virtual element; so get the real parent node
                            parentNode = (parentNode.nodeType === 8 && parentNode.parentNode) || parentNode;

                            // Rule [A]
                            while (continuousNodeArray.length && continuousNodeArray[0].parentNode !== parentNode)
                                continuousNodeArray.splice(0, 1);

                            // Rule [B]
                            while (continuousNodeArray.length > 1 && continuousNodeArray[continuousNodeArray.length - 1].parentNode !== parentNode)
                                continuousNodeArray.length--;

                            // Rule [C]
                            if (continuousNodeArray.length > 1) {
                                var current = continuousNodeArray[0], last = continuousNodeArray[continuousNodeArray.length - 1];
                                // Replace with the actual new continuous node set
                                continuousNodeArray.length = 0;
                                while (current !== last) {
                                    continuousNodeArray.push(current);
                                    current = current.nextSibling;
                                }
                                continuousNodeArray.push(last);
                            }
                        }
                        return continuousNodeArray;
                    },

                    setOptionNodeSelectionState: function (optionNode, isSelected) {
                        // IE6 sometimes throws "unknown error" if you try to write to .selected directly, whereas Firefox struggles with setAttribute. Pick one based on browser.
                        if (ieVersion < 7)
                            optionNode.setAttribute("selected", isSelected);
                        else
                            optionNode.selected = isSelected;
                    },

                    stringTrim: function (string) {
                        return string === null || string === undefined ? '' :
                            string.trim ?
                                string.trim() :
                                string.toString().replace(/^[\s\xa0]+|[\s\xa0]+$/g, '');
                    },

                    stringStartsWith: function (string, startsWith) {
                        string = string || "";
                        if (startsWith.length > string.length)
                            return false;
                        return string.substring(0, startsWith.length) === startsWith;
                    },

                    domNodeIsContainedBy: function (node, containedByNode) {
                        if (node === containedByNode)
                            return true;
                        if (node.nodeType === 11)
                            return false; // Fixes issue #1162 - can't use node.contains for document fragments on IE8
                        if (containedByNode.contains)
                            return containedByNode.contains(node.nodeType !== 1 ? node.parentNode : node);
                        if (containedByNode.compareDocumentPosition)
                            return (containedByNode.compareDocumentPosition(node) & 16) == 16;
                        while (node && node != containedByNode) {
                            node = node.parentNode;
                        }
                        return !!node;
                    },

                    domNodeIsAttachedToDocument: function (node) {
                        return ko.utils.domNodeIsContainedBy(node, node.ownerDocument.documentElement);
                    },

                    anyDomNodeIsAttachedToDocument: function (nodes) {
                        return !!ko.utils.arrayFirst(nodes, ko.utils.domNodeIsAttachedToDocument);
                    },

                    tagNameLower: function (element) {
                        // For HTML elements, tagName will always be upper case; for XHTML elements, it'll be lower case.
                        // Possible future optimization: If we know it's an element from an XHTML document (not HTML),
                        // we don't need to do the .toLowerCase() as it will always be lower case anyway.
                        return element && element.tagName && element.tagName.toLowerCase();
                    },

                    catchFunctionErrors: function (delegate) {
                        return ko['onError'] ? function () {
                            try {
                                return delegate.apply(this, arguments);
                            } catch (e) {
                                ko['onError'] && ko['onError'](e);
                                throw e;
                            }
                        } : delegate;
                    },

                    setTimeout: function (handler, timeout) {
                        return setTimeout(ko.utils.catchFunctionErrors(handler), timeout);
                    },

                    deferError: function (error) {
                        setTimeout(function () {
                            ko['onError'] && ko['onError'](error);
                            throw error;
                        }, 0);
                    },

                    registerEventHandler: function (element, eventType, handler) {
                        var wrappedHandler = ko.utils.catchFunctionErrors(handler);

                        var mustUseAttachEvent = eventsThatMustBeRegisteredUsingAttachEvent[eventType];
                        if (!ko.options['useOnlyNativeEvents'] && !mustUseAttachEvent && jQueryInstance) {
                            if (!jQueryEventAttachName) {
                                jQueryEventAttachName = (typeof jQueryInstance(element)['on'] == 'function') ? 'on' : 'bind';
                            }
                            jQueryInstance(element)[jQueryEventAttachName](eventType, wrappedHandler);
                        } else if (!mustUseAttachEvent && typeof element.addEventListener == "function")
                            element.addEventListener(eventType, wrappedHandler, false);
                        else if (typeof element.attachEvent != "undefined") {
                            var attachEventHandler = function (event) { wrappedHandler.call(element, event); },
                                attachEventName = "on" + eventType;
                            element.attachEvent(attachEventName, attachEventHandler);

                            // IE does not dispose attachEvent handlers automatically (unlike with addEventListener)
                            // so to avoid leaks, we have to remove them manually. See bug #856
                            ko.utils.domNodeDisposal.addDisposeCallback(element, function () {
                                element.detachEvent(attachEventName, attachEventHandler);
                            });
                        } else
                            throw new Error("Browser doesn't support addEventListener or attachEvent");
                    },

                    triggerEvent: function (element, eventType) {
                        if (!(element && element.nodeType))
                            throw new Error("element must be a DOM node when calling triggerEvent");

                        // For click events on checkboxes and radio buttons, jQuery toggles the element checked state *after* the
                        // event handler runs instead of *before*. (This was fixed in 1.9 for checkboxes but not for radio buttons.)
                        // IE doesn't change the checked state when you trigger the click event using "fireEvent".
                        // In both cases, we'll use the click method instead.
                        var useClickWorkaround = isClickOnCheckableElement(element, eventType);

                        if (!ko.options['useOnlyNativeEvents'] && jQueryInstance && !useClickWorkaround) {
                            jQueryInstance(element)['trigger'](eventType);
                        } else if (typeof document.createEvent == "function") {
                            if (typeof element.dispatchEvent == "function") {
                                var eventCategory = knownEventTypesByEventName[eventType] || "HTMLEvents";
                                var event = document.createEvent(eventCategory);
                                event.initEvent(eventType, true, true, window, 0, 0, 0, 0, 0, false, false, false, false, 0, element);
                                element.dispatchEvent(event);
                            }
                            else
                                throw new Error("The supplied element doesn't support dispatchEvent");
                        } else if (useClickWorkaround && element.click) {
                            element.click();
                        } else if (typeof element.fireEvent != "undefined") {
                            element.fireEvent("on" + eventType);
                        } else {
                            throw new Error("Browser doesn't support triggering events");
                        }
                    },

                    unwrapObservable: function (value) {
                        return ko.isObservable(value) ? value() : value;
                    },

                    peekObservable: function (value) {
                        return ko.isObservable(value) ? value.peek() : value;
                    },

                    toggleDomNodeCssClass: toggleDomNodeCssClass,

                    setTextContent: function (element, textContent) {
                        var value = ko.utils.unwrapObservable(textContent);
                        if ((value === null) || (value === undefined))
                            value = "";

                        // We need there to be exactly one child: a text node.
                        // If there are no children, more than one, or if it's not a text node,
                        // we'll clear everything and create a single text node.
                        var innerTextNode = ko.virtualElements.firstChild(element);
                        if (!innerTextNode || innerTextNode.nodeType != 3 || ko.virtualElements.nextSibling(innerTextNode)) {
                            ko.virtualElements.setDomNodeChildren(element, [element.ownerDocument.createTextNode(value)]);
                        } else {
                            innerTextNode.data = value;
                        }

                        ko.utils.forceRefresh(element);
                    },

                    setElementName: function (element, name) {
                        element.name = name;

                        // Workaround IE 6/7 issue
                        // - https://github.com/SteveSanderson/knockout/issues/197
                        // - http://www.matts411.com/post/setting_the_name_attribute_in_ie_dom/
                        if (ieVersion <= 7) {
                            try {
                                var escapedName = element.name.replace(/[&<>'"]/g, function (r) { return "&#" + r.charCodeAt(0) + ";"; });
                                element.mergeAttributes(document.createElement("<input name='" + escapedName + "'/>"), false);
                            }
                            catch (e) { } // For IE9 with doc mode "IE9 Standards" and browser mode "IE9 Compatibility View"
                        }
                    },

                    forceRefresh: function (node) {
                        // Workaround for an IE9 rendering bug - https://github.com/SteveSanderson/knockout/issues/209
                        if (ieVersion >= 9) {
                            // For text nodes and comment nodes (most likely virtual elements), we will have to refresh the container
                            var elem = node.nodeType == 1 ? node : node.parentNode;
                            if (elem.style)
                                elem.style.zoom = elem.style.zoom;
                        }
                    },

                    ensureSelectElementIsRenderedCorrectly: function (selectElement) {
                        // Workaround for IE9 rendering bug - it doesn't reliably display all the text in dynamically-added select boxes unless you force it to re-render by updating the width.
                        // (See https://github.com/SteveSanderson/knockout/issues/312, http://stackoverflow.com/questions/5908494/select-only-shows-first-char-of-selected-option)
                        // Also fixes IE7 and IE8 bug that causes selects to be zero width if enclosed by 'if' or 'with'. (See issue #839)
                        if (ieVersion) {
                            var originalWidth = selectElement.style.width;
                            selectElement.style.width = 0;
                            selectElement.style.width = originalWidth;
                        }
                    },

                    range: function (min, max) {
                        min = ko.utils.unwrapObservable(min);
                        max = ko.utils.unwrapObservable(max);
                        var result = [];
                        for (var i = min; i <= max; i++)
                            result.push(i);
                        return result;
                    },

                    makeArray: function (arrayLikeObject) {
                        var result = [];
                        for (var i = 0, j = arrayLikeObject.length; i < j; i++) {
                            result.push(arrayLikeObject[i]);
                        };
                        return result;
                    },

                    createSymbolOrString: function (identifier) {
                        return canUseSymbols ? Symbol(identifier) : identifier;
                    },

                    isIe6: isIe6,
                    isIe7: isIe7,
                    ieVersion: ieVersion,

                    getFormFields: function (form, fieldName) {
                        var fields = ko.utils.makeArray(form.getElementsByTagName("input")).concat(ko.utils.makeArray(form.getElementsByTagName("textarea")));
                        var isMatchingField = (typeof fieldName == 'string')
                            ? function (field) { return field.name === fieldName }
                            : function (field) { return fieldName.test(field.name) }; // Treat fieldName as regex or object containing predicate
                        var matches = [];
                        for (var i = fields.length - 1; i >= 0; i--) {
                            if (isMatchingField(fields[i]))
                                matches.push(fields[i]);
                        };
                        return matches;
                    },

                    parseJson: function (jsonString) {
                        if (typeof jsonString == "string") {
                            jsonString = ko.utils.stringTrim(jsonString);
                            if (jsonString) {
                                if (JSON && JSON.parse) // Use native parsing where available
                                    return JSON.parse(jsonString);
                                return (new Function("return " + jsonString))(); // Fallback on less safe parsing for older browsers
                            }
                        }
                        return null;
                    },

                    stringifyJson: function (data, replacer, space) {   // replacer and space are optional
                        if (!JSON || !JSON.stringify)
                            throw new Error("Cannot find JSON.stringify(). Some browsers (e.g., IE < 8) don't support it natively, but you can overcome this by adding a script reference to json2.js, downloadable from http://www.json.org/json2.js");
                        return JSON.stringify(ko.utils.unwrapObservable(data), replacer, space);
                    },

                    postJson: function (urlOrForm, data, options) {
                        options = options || {};
                        var params = options['params'] || {};
                        var includeFields = options['includeFields'] || this.fieldsIncludedWithJsonPost;
                        var url = urlOrForm;

                        // If we were given a form, use its 'action' URL and pick out any requested field values
                        if ((typeof urlOrForm == 'object') && (ko.utils.tagNameLower(urlOrForm) === "form")) {
                            var originalForm = urlOrForm;
                            url = originalForm.action;
                            for (var i = includeFields.length - 1; i >= 0; i--) {
                                var fields = ko.utils.getFormFields(originalForm, includeFields[i]);
                                for (var j = fields.length - 1; j >= 0; j--)
                                    params[fields[j].name] = fields[j].value;
                            }
                        }

                        data = ko.utils.unwrapObservable(data);
                        var form = document.createElement("form");
                        form.style.display = "none";
                        form.action = url;
                        form.method = "post";
                        for (var key in data) {
                            // Since 'data' this is a model object, we include all properties including those inherited from its prototype
                            var input = document.createElement("input");
                            input.type = "hidden";
                            input.name = key;
                            input.value = ko.utils.stringifyJson(ko.utils.unwrapObservable(data[key]));
                            form.appendChild(input);
                        }
                        objectForEach(params, function (key, value) {
                            var input = document.createElement("input");
                            input.type = "hidden";
                            input.name = key;
                            input.value = value;
                            form.appendChild(input);
                        });
                        document.body.appendChild(form);
                        options['submitter'] ? options['submitter'](form) : form.submit();
                        setTimeout(function () { form.parentNode.removeChild(form); }, 0);
                    }
                }
            }());

            ko.exportSymbol('utils', ko.utils);
            ko.exportSymbol('utils.arrayForEach', ko.utils.arrayForEach);
            ko.exportSymbol('utils.arrayFirst', ko.utils.arrayFirst);
            ko.exportSymbol('utils.arrayFilter', ko.utils.arrayFilter);
            ko.exportSymbol('utils.arrayGetDistinctValues', ko.utils.arrayGetDistinctValues);
            ko.exportSymbol('utils.arrayIndexOf', ko.utils.arrayIndexOf);
            ko.exportSymbol('utils.arrayMap', ko.utils.arrayMap);
            ko.exportSymbol('utils.arrayPushAll', ko.utils.arrayPushAll);
            ko.exportSymbol('utils.arrayRemoveItem', ko.utils.arrayRemoveItem);
            ko.exportSymbol('utils.cloneNodes', ko.utils.cloneNodes);
            ko.exportSymbol('utils.createSymbolOrString', ko.utils.createSymbolOrString);
            ko.exportSymbol('utils.extend', ko.utils.extend);
            ko.exportSymbol('utils.fieldsIncludedWithJsonPost', ko.utils.fieldsIncludedWithJsonPost);
            ko.exportSymbol('utils.getFormFields', ko.utils.getFormFields);
            ko.exportSymbol('utils.objectMap', ko.utils.objectMap);
            ko.exportSymbol('utils.peekObservable', ko.utils.peekObservable);
            ko.exportSymbol('utils.postJson', ko.utils.postJson);
            ko.exportSymbol('utils.parseJson', ko.utils.parseJson);
            ko.exportSymbol('utils.registerEventHandler', ko.utils.registerEventHandler);
            ko.exportSymbol('utils.stringifyJson', ko.utils.stringifyJson);
            ko.exportSymbol('utils.range', ko.utils.range);
            ko.exportSymbol('utils.toggleDomNodeCssClass', ko.utils.toggleDomNodeCssClass);
            ko.exportSymbol('utils.triggerEvent', ko.utils.triggerEvent);
            ko.exportSymbol('utils.unwrapObservable', ko.utils.unwrapObservable);
            ko.exportSymbol('utils.objectForEach', ko.utils.objectForEach);
            ko.exportSymbol('utils.addOrRemoveItem', ko.utils.addOrRemoveItem);
            ko.exportSymbol('utils.setTextContent', ko.utils.setTextContent);
            ko.exportSymbol('unwrap', ko.utils.unwrapObservable); // Convenient shorthand, because this is used so commonly

            if (!Function.prototype['bind']) {
                // Function.prototype.bind is a standard part of ECMAScript 5th Edition (December 2009, http://www.ecma-international.org/publications/files/ECMA-ST/ECMA-262.pdf)
                // In case the browser doesn't implement it natively, provide a JavaScript implementation. This implementation is based on the one in prototype.js
                Function.prototype['bind'] = function (object) {
                    var originalFunction = this;
                    if (arguments.length === 1) {
                        return function () {
                            return originalFunction.apply(object, arguments);
                        };
                    } else {
                        var partialArgs = Array.prototype.slice.call(arguments, 1);
                        return function () {
                            var args = partialArgs.slice(0);
                            args.push.apply(args, arguments);
                            return originalFunction.apply(object, args);
                        };
                    }
                };
            }

            ko.utils.domData = new (function () {
                var uniqueId = 0;
                var dataStoreKeyExpandoPropertyName = "__ko__" + (new Date).getTime();
                var dataStore = {};

                var getDataForNode, clear;
                if (!ko.utils.ieVersion) {
                    // We considered using WeakMap, but it has a problem in IE 11 and Edge that prevents using
                    // it cross-window, so instead we just store the data directly on the node.
                    // See https://github.com/knockout/knockout/issues/2141
                    getDataForNode = function (node, createIfNotFound) {
                        var dataForNode = node[dataStoreKeyExpandoPropertyName];
                        if (!dataForNode && createIfNotFound) {
                            dataForNode = node[dataStoreKeyExpandoPropertyName] = {};
                        }
                        return dataForNode;
                    };
                    clear = function (node) {
                        if (node[dataStoreKeyExpandoPropertyName]) {
                            delete node[dataStoreKeyExpandoPropertyName];
                            return true; // Exposing "did clean" flag purely so specs can infer whether things have been cleaned up as intended
                        }
                        return false;
                    };
                } else {
                    // Old IE versions have memory issues if you store objects on the node, so we use a
                    // separate data storage and link to it from the node using a string key.
                    getDataForNode = function (node, createIfNotFound) {
                        var dataStoreKey = node[dataStoreKeyExpandoPropertyName];
                        var hasExistingDataStore = dataStoreKey && (dataStoreKey !== "null") && dataStore[dataStoreKey];
                        if (!hasExistingDataStore) {
                            if (!createIfNotFound)
                                return undefined;
                            dataStoreKey = node[dataStoreKeyExpandoPropertyName] = "ko" + uniqueId++;
                            dataStore[dataStoreKey] = {};
                        }
                        return dataStore[dataStoreKey];
                    };
                    clear = function (node) {
                        var dataStoreKey = node[dataStoreKeyExpandoPropertyName];
                        if (dataStoreKey) {
                            delete dataStore[dataStoreKey];
                            node[dataStoreKeyExpandoPropertyName] = null;
                            return true; // Exposing "did clean" flag purely so specs can infer whether things have been cleaned up as intended
                        }
                        return false;
                    };
                }

                return {
                    get: function (node, key) {
                        var dataForNode = getDataForNode(node, false);
                        return dataForNode && dataForNode[key];
                    },
                    set: function (node, key, value) {
                        // Make sure we don't actually create a new domData key if we are actually deleting a value
                        var dataForNode = getDataForNode(node, value !== undefined /* createIfNotFound */);
                        dataForNode && (dataForNode[key] = value);
                    },
                    getOrSet: function (node, key, value) {
                        var dataForNode = getDataForNode(node, true /* createIfNotFound */);
                        return dataForNode[key] || (dataForNode[key] = value);
                    },
                    clear: clear,

                    nextKey: function () {
                        return (uniqueId++) + dataStoreKeyExpandoPropertyName;
                    }
                };
            })();

            ko.exportSymbol('utils.domData', ko.utils.domData);
            ko.exportSymbol('utils.domData.clear', ko.utils.domData.clear); // Exporting only so specs can clear up after themselves fully

            ko.utils.domNodeDisposal = new (function () {
                var domDataKey = ko.utils.domData.nextKey();
                var cleanableNodeTypes = { 1: true, 8: true, 9: true };       // Element, Comment, Document
                var cleanableNodeTypesWithDescendants = { 1: true, 9: true }; // Element, Document

                function getDisposeCallbacksCollection(node, createIfNotFound) {
                    var allDisposeCallbacks = ko.utils.domData.get(node, domDataKey);
                    if ((allDisposeCallbacks === undefined) && createIfNotFound) {
                        allDisposeCallbacks = [];
                        ko.utils.domData.set(node, domDataKey, allDisposeCallbacks);
                    }
                    return allDisposeCallbacks;
                }
                function destroyCallbacksCollection(node) {
                    ko.utils.domData.set(node, domDataKey, undefined);
                }

                function cleanSingleNode(node) {
                    // Run all the dispose callbacks
                    var callbacks = getDisposeCallbacksCollection(node, false);
                    if (callbacks) {
                        callbacks = callbacks.slice(0); // Clone, as the array may be modified during iteration (typically, callbacks will remove themselves)
                        for (var i = 0; i < callbacks.length; i++)
                            callbacks[i](node);
                    }

                    // Erase the DOM data
                    ko.utils.domData.clear(node);

                    // Perform cleanup needed by external libraries (currently only jQuery, but can be extended)
                    ko.utils.domNodeDisposal["cleanExternalData"](node);

                    // Clear any immediate-child comment nodes, as these wouldn't have been found by
                    // node.getElementsByTagName("*") in cleanNode() (comment nodes aren't elements)
                    if (cleanableNodeTypesWithDescendants[node.nodeType]) {
                        cleanNodesInList(node.childNodes, true/*onlyComments*/);
                    }
                }

                function cleanNodesInList(nodeList, onlyComments) {
                    var cleanedNodes = [], lastCleanedNode;
                    for (var i = 0; i < nodeList.length; i++) {
                        if (!onlyComments || nodeList[i].nodeType === 8) {
                            cleanSingleNode(cleanedNodes[cleanedNodes.length] = lastCleanedNode = nodeList[i]);
                            if (nodeList[i] !== lastCleanedNode) {
                                while (i-- && ko.utils.arrayIndexOf(cleanedNodes, nodeList[i]) == -1) { }
                            }
                        }
                    }
                }

                return {
                    addDisposeCallback: function (node, callback) {
                        if (typeof callback != "function")
                            throw new Error("Callback must be a function");
                        getDisposeCallbacksCollection(node, true).push(callback);
                    },

                    removeDisposeCallback: function (node, callback) {
                        var callbacksCollection = getDisposeCallbacksCollection(node, false);
                        if (callbacksCollection) {
                            ko.utils.arrayRemoveItem(callbacksCollection, callback);
                            if (callbacksCollection.length == 0)
                                destroyCallbacksCollection(node);
                        }
                    },

                    cleanNode: function (node) {
                        ko.dependencyDetection.ignore(function () {
                            // First clean this node, where applicable
                            if (cleanableNodeTypes[node.nodeType]) {
                                cleanSingleNode(node);

                                // ... then its descendants, where applicable
                                if (cleanableNodeTypesWithDescendants[node.nodeType]) {
                                    cleanNodesInList(node.getElementsByTagName("*"));
                                }
                            }
                        });

                        return node;
                    },

                    removeNode: function (node) {
                        ko.cleanNode(node);
                        if (node.parentNode)
                            node.parentNode.removeChild(node);
                    },

                    "cleanExternalData": function (node) {
                        // Special support for jQuery here because it's so commonly used.
                        // Many jQuery plugins (including jquery.tmpl) store data using jQuery's equivalent of domData
                        // so notify it to tear down any resources associated with the node & descendants here.
                        if (jQueryInstance && (typeof jQueryInstance['cleanData'] == "function"))
                            jQueryInstance['cleanData']([node]);
                    }
                };
            })();
            ko.cleanNode = ko.utils.domNodeDisposal.cleanNode; // Shorthand name for convenience
            ko.removeNode = ko.utils.domNodeDisposal.removeNode; // Shorthand name for convenience
            ko.exportSymbol('cleanNode', ko.cleanNode);
            ko.exportSymbol('removeNode', ko.removeNode);
            ko.exportSymbol('utils.domNodeDisposal', ko.utils.domNodeDisposal);
            ko.exportSymbol('utils.domNodeDisposal.addDisposeCallback', ko.utils.domNodeDisposal.addDisposeCallback);
            ko.exportSymbol('utils.domNodeDisposal.removeDisposeCallback', ko.utils.domNodeDisposal.removeDisposeCallback);
            (function () {
                var none = [0, "", ""],
                    table = [1, "<table>", "</table>"],
                    tbody = [2, "<table><tbody>", "</tbody></table>"],
                    tr = [3, "<table><tbody><tr>", "</tr></tbody></table>"],
                    select = [1, "<select multiple='multiple'>", "</select>"],
                    lookup = {
                        'thead': table,
                        'tbody': table,
                        'tfoot': table,
                        'tr': tbody,
                        'td': tr,
                        'th': tr,
                        'option': select,
                        'optgroup': select
                    },

                    // This is needed for old IE if you're *not* using either jQuery or innerShiv. Doesn't affect other cases.
                    mayRequireCreateElementHack = ko.utils.ieVersion <= 8;

                function getWrap(tags) {
                    var m = tags.match(/^(?:<!--.*?-->\s*?)*?<([a-z]+)[\s>]/);
                    return (m && lookup[m[1]]) || none;
                }

                function simpleHtmlParse(html, documentContext) {
                    documentContext || (documentContext = document);
                    var windowContext = documentContext['parentWindow'] || documentContext['defaultView'] || window;

                    // Based on jQuery's "clean" function, but only accounting for table-related elements.
                    // If you have referenced jQuery, this won't be used anyway - KO will use jQuery's "clean" function directly

                    // Note that there's still an issue in IE < 9 whereby it will discard comment nodes that are the first child of
                    // a descendant node. For example: "<div><!-- mycomment -->abc</div>" will get parsed as "<div>abc</div>"
                    // This won't affect anyone who has referenced jQuery, and there's always the workaround of inserting a dummy node
                    // (possibly a text node) in front of the comment. So, KO does not attempt to workaround this IE issue automatically at present.

                    // Trim whitespace, otherwise indexOf won't work as expected
                    var tags = ko.utils.stringTrim(html).toLowerCase(), div = documentContext.createElement("div"),
                        wrap = getWrap(tags),
                        depth = wrap[0];

                    // Go to html and back, then peel off extra wrappers
                    // Note that we always prefix with some dummy text, because otherwise, IE<9 will strip out leading comment nodes in descendants. Total madness.
                    var markup = "ignored<div>" + wrap[1] + html + wrap[2] + "</div>";
                    if (typeof windowContext['innerShiv'] == "function") {
                        // Note that innerShiv is deprecated in favour of html5shiv. We should consider adding
                        // support for html5shiv (except if no explicit support is needed, e.g., if html5shiv
                        // somehow shims the native APIs so it just works anyway)
                        div.appendChild(windowContext['innerShiv'](markup));
                    } else {
                        if (mayRequireCreateElementHack) {
                            // The document.createElement('my-element') trick to enable custom elements in IE6-8
                            // only works if we assign innerHTML on an element associated with that document.
                            documentContext.body.appendChild(div);
                        }

                        div.innerHTML = markup;

                        if (mayRequireCreateElementHack) {
                            div.parentNode.removeChild(div);
                        }
                    }

                    // Move to the right depth
                    while (depth--)
                        div = div.lastChild;

                    return ko.utils.makeArray(div.lastChild.childNodes);
                }

                function jQueryHtmlParse(html, documentContext) {
                    // jQuery's "parseHTML" function was introduced in jQuery 1.8.0 and is a documented public API.
                    if (jQueryInstance['parseHTML']) {
                        return jQueryInstance['parseHTML'](html, documentContext) || []; // Ensure we always return an array and never null
                    } else {
                        // For jQuery < 1.8.0, we fall back on the undocumented internal "clean" function.
                        var elems = jQueryInstance['clean']([html], documentContext);

                        // As of jQuery 1.7.1, jQuery parses the HTML by appending it to some dummy parent nodes held in an in-memory document fragment.
                        // Unfortunately, it never clears the dummy parent nodes from the document fragment, so it leaks memory over time.
                        // Fix this by finding the top-most dummy parent element, and detaching it from its owner fragment.
                        if (elems && elems[0]) {
                            // Find the top-most parent element that's a direct child of a document fragment
                            var elem = elems[0];
                            while (elem.parentNode && elem.parentNode.nodeType !== 11 /* i.e., DocumentFragment */)
                                elem = elem.parentNode;
                            // ... then detach it
                            if (elem.parentNode)
                                elem.parentNode.removeChild(elem);
                        }

                        return elems;
                    }
                }

                ko.utils.parseHtmlFragment = function (html, documentContext) {
                    return jQueryInstance ?
                        jQueryHtmlParse(html, documentContext) :   // As below, benefit from jQuery's optimisations where possible
                        simpleHtmlParse(html, documentContext);  // ... otherwise, this simple logic will do in most common cases.
                };

                ko.utils.parseHtmlForTemplateNodes = function (html, documentContext) {
                    var nodes = ko.utils.parseHtmlFragment(html, documentContext);
                    return (nodes.length && nodes[0].parentElement) || ko.utils.moveCleanedNodesToContainerElement(nodes);
                };

                ko.utils.setHtml = function (node, html) {
                    ko.utils.emptyDomNode(node);

                    // There's no legitimate reason to display a stringified observable without unwrapping it, so we'll unwrap it
                    html = ko.utils.unwrapObservable(html);

                    if ((html !== null) && (html !== undefined)) {
                        if (typeof html != 'string')
                            html = html.toString();

                        // jQuery contains a lot of sophisticated code to parse arbitrary HTML fragments,
                        // for example <tr> elements which are not normally allowed to exist on their own.
                        // If you've referenced jQuery we'll use that rather than duplicating its code.
                        if (jQueryInstance) {
                            jQueryInstance(node)['html'](html);
                        } else {
                            // ... otherwise, use KO's own parsing logic.
                            var parsedNodes = ko.utils.parseHtmlFragment(html, node.ownerDocument);
                            for (var i = 0; i < parsedNodes.length; i++)
                                node.appendChild(parsedNodes[i]);
                        }
                    }
                };
            })();

            ko.exportSymbol('utils.parseHtmlFragment', ko.utils.parseHtmlFragment);
            ko.exportSymbol('utils.setHtml', ko.utils.setHtml);

            ko.memoization = (function () {
                var memos = {};

                function randomMax8HexChars() {
                    return (((1 + Math.random()) * 0x100000000) | 0).toString(16).substring(1);
                }
                function generateRandomId() {
                    return randomMax8HexChars() + randomMax8HexChars();
                }
                function findMemoNodes(rootNode, appendToArray) {
                    if (!rootNode)
                        return;
                    if (rootNode.nodeType == 8) {
                        var memoId = ko.memoization.parseMemoText(rootNode.nodeValue);
                        if (memoId != null)
                            appendToArray.push({ domNode: rootNode, memoId: memoId });
                    } else if (rootNode.nodeType == 1) {
                        for (var i = 0, childNodes = rootNode.childNodes, j = childNodes.length; i < j; i++)
                            findMemoNodes(childNodes[i], appendToArray);
                    }
                }

                return {
                    memoize: function (callback) {
                        if (typeof callback != "function")
                            throw new Error("You can only pass a function to ko.memoization.memoize()");
                        var memoId = generateRandomId();
                        memos[memoId] = callback;
                        return "<!--[ko_memo:" + memoId + "]-->";
                    },

                    unmemoize: function (memoId, callbackParams) {
                        var callback = memos[memoId];
                        if (callback === undefined)
                            throw new Error("Couldn't find any memo with ID " + memoId + ". Perhaps it's already been unmemoized.");
                        try {
                            callback.apply(null, callbackParams || []);
                            return true;
                        }
                        finally { delete memos[memoId]; }
                    },

                    unmemoizeDomNodeAndDescendants: function (domNode, extraCallbackParamsArray) {
                        var memos = [];
                        findMemoNodes(domNode, memos);
                        for (var i = 0, j = memos.length; i < j; i++) {
                            var node = memos[i].domNode;
                            var combinedParams = [node];
                            if (extraCallbackParamsArray)
                                ko.utils.arrayPushAll(combinedParams, extraCallbackParamsArray);
                            ko.memoization.unmemoize(memos[i].memoId, combinedParams);
                            node.nodeValue = ""; // Neuter this node so we don't try to unmemoize it again
                            if (node.parentNode)
                                node.parentNode.removeChild(node); // If possible, erase it totally (not always possible - someone else might just hold a reference to it then call unmemoizeDomNodeAndDescendants again)
                        }
                    },

                    parseMemoText: function (memoText) {
                        var match = memoText.match(/^\[ko_memo\:(.*?)\]$/);
                        return match ? match[1] : null;
                    }
                };
            })();

            ko.exportSymbol('memoization', ko.memoization);
            ko.exportSymbol('memoization.memoize', ko.memoization.memoize);
            ko.exportSymbol('memoization.unmemoize', ko.memoization.unmemoize);
            ko.exportSymbol('memoization.parseMemoText', ko.memoization.parseMemoText);
            ko.exportSymbol('memoization.unmemoizeDomNodeAndDescendants', ko.memoization.unmemoizeDomNodeAndDescendants);
            ko.tasks = (function () {
                var scheduler,
                    taskQueue = [],
                    taskQueueLength = 0,
                    nextHandle = 1,
                    nextIndexToProcess = 0;

                if (window['MutationObserver']) {
                    // Chrome 27+, Firefox 14+, IE 11+, Opera 15+, Safari 6.1+
                    // From https://github.com/petkaantonov/bluebird * Copyright (c) 2014 Petka Antonov * License: MIT
                    scheduler = (function (callback) {
                        var div = document.createElement("div");
                        new MutationObserver(callback).observe(div, { attributes: true });
                        return function () { div.classList.toggle("foo"); };
                    })(scheduledProcess);
                } else if (document && "onreadystatechange" in document.createElement("script")) {
                    // IE 6-10
                    // From https://github.com/YuzuJS/setImmediate * Copyright (c) 2012 Barnesandnoble.com, llc, Donavon West, and Domenic Denicola * License: MIT
                    scheduler = function (callback) {
                        var script = document.createElement("script");
                        script.onreadystatechange = function () {
                            script.onreadystatechange = null;
                            document.documentElement.removeChild(script);
                            script = null;
                            callback();
                        };
                        document.documentElement.appendChild(script);
                    };
                } else {
                    scheduler = function (callback) {
                        setTimeout(callback, 0);
                    };
                }

                function processTasks() {
                    if (taskQueueLength) {
                        // Each mark represents the end of a logical group of tasks and the number of these groups is
                        // limited to prevent unchecked recursion.
                        var mark = taskQueueLength, countMarks = 0;

                        // nextIndexToProcess keeps track of where we are in the queue; processTasks can be called recursively without issue
                        for (var task; nextIndexToProcess < taskQueueLength;) {
                            if (task = taskQueue[nextIndexToProcess++]) {
                                if (nextIndexToProcess > mark) {
                                    if (++countMarks >= 5000) {
                                        nextIndexToProcess = taskQueueLength;   // skip all tasks remaining in the queue since any of them could be causing the recursion
                                        ko.utils.deferError(Error("'Too much recursion' after processing " + countMarks + " task groups."));
                                        break;
                                    }
                                    mark = taskQueueLength;
                                }
                                try {
                                    task();
                                } catch (ex) {
                                    ko.utils.deferError(ex);
                                }
                            }
                        }
                    }
                }

                function scheduledProcess() {
                    processTasks();

                    // Reset the queue
                    nextIndexToProcess = taskQueueLength = taskQueue.length = 0;
                }

                function scheduleTaskProcessing() {
                    ko.tasks['scheduler'](scheduledProcess);
                }

                var tasks = {
                    'scheduler': scheduler,     // Allow overriding the scheduler

                    schedule: function (func) {
                        if (!taskQueueLength) {
                            scheduleTaskProcessing();
                        }

                        taskQueue[taskQueueLength++] = func;
                        return nextHandle++;
                    },

                    cancel: function (handle) {
                        var index = handle - (nextHandle - taskQueueLength);
                        if (index >= nextIndexToProcess && index < taskQueueLength) {
                            taskQueue[index] = null;
                        }
                    },

                    // For testing only: reset the queue and return the previous queue length
                    'resetForTesting': function () {
                        var length = taskQueueLength - nextIndexToProcess;
                        nextIndexToProcess = taskQueueLength = taskQueue.length = 0;
                        return length;
                    },

                    runEarly: processTasks
                };

                return tasks;
            })();

            ko.exportSymbol('tasks', ko.tasks);
            ko.exportSymbol('tasks.schedule', ko.tasks.schedule);
            //ko.exportSymbol('tasks.cancel', ko.tasks.cancel);  "cancel" isn't minified
            ko.exportSymbol('tasks.runEarly', ko.tasks.runEarly);
            ko.extenders = {
                'throttle': function (target, timeout) {
                    // Throttling means two things:

                    // (1) For dependent observables, we throttle *evaluations* so that, no matter how fast its dependencies
                    //     notify updates, the target doesn't re-evaluate (and hence doesn't notify) faster than a certain rate
                    target['throttleEvaluation'] = timeout;

                    // (2) For writable targets (observables, or writable dependent observables), we throttle *writes*
                    //     so the target cannot change value synchronously or faster than a certain rate
                    var writeTimeoutInstance = null;
                    return ko.dependentObservable({
                        'read': target,
                        'write': function (value) {
                            clearTimeout(writeTimeoutInstance);
                            writeTimeoutInstance = ko.utils.setTimeout(function () {
                                target(value);
                            }, timeout);
                        }
                    });
                },

                'rateLimit': function (target, options) {
                    var timeout, method, limitFunction;

                    if (typeof options == 'number') {
                        timeout = options;
                    } else {
                        timeout = options['timeout'];
                        method = options['method'];
                    }

                    // rateLimit supersedes deferred updates
                    target._deferUpdates = false;

                    limitFunction = typeof method == 'function' ? method : method == 'notifyWhenChangesStop' ? debounce : throttle;
                    target.limit(function (callback) {
                        return limitFunction(callback, timeout, options);
                    });
                },

                'deferred': function (target, options) {
                    if (options !== true) {
                        throw new Error('The \'deferred\' extender only accepts the value \'true\', because it is not supported to turn deferral off once enabled.')
                    }

                    if (!target._deferUpdates) {
                        target._deferUpdates = true;
                        target.limit(function (callback) {
                            var handle,
                                ignoreUpdates = false;
                            return function () {
                                if (!ignoreUpdates) {
                                    ko.tasks.cancel(handle);
                                    handle = ko.tasks.schedule(callback);

                                    try {
                                        ignoreUpdates = true;
                                        target['notifySubscribers'](undefined, 'dirty');
                                    } finally {
                                        ignoreUpdates = false;
                                    }
                                }
                            };
                        });
                    }
                },

                'notify': function (target, notifyWhen) {
                    target["equalityComparer"] = notifyWhen == "always" ?
                        null :  // null equalityComparer means to always notify
                        valuesArePrimitiveAndEqual;
                }
            };

            var primitiveTypes = { 'undefined': 1, 'boolean': 1, 'number': 1, 'string': 1 };
            function valuesArePrimitiveAndEqual(a, b) {
                var oldValueIsPrimitive = (a === null) || (typeof (a) in primitiveTypes);
                return oldValueIsPrimitive ? (a === b) : false;
            }

            function throttle(callback, timeout) {
                var timeoutInstance;
                return function () {
                    if (!timeoutInstance) {
                        timeoutInstance = ko.utils.setTimeout(function () {
                            timeoutInstance = undefined;
                            callback();
                        }, timeout);
                    }
                };
            }

            function debounce(callback, timeout) {
                var timeoutInstance;
                return function () {
                    clearTimeout(timeoutInstance);
                    timeoutInstance = ko.utils.setTimeout(callback, timeout);
                };
            }

            function applyExtenders(requestedExtenders) {
                var target = this;
                if (requestedExtenders) {
                    ko.utils.objectForEach(requestedExtenders, function (key, value) {
                        var extenderHandler = ko.extenders[key];
                        if (typeof extenderHandler == 'function') {
                            target = extenderHandler(target, value) || target;
                        }
                    });
                }
                return target;
            }

            ko.exportSymbol('extenders', ko.extenders);

            ko.subscription = function (target, callback, disposeCallback) {
                this._target = target;
                this._callback = callback;
                this._disposeCallback = disposeCallback;
                this._isDisposed = false;
                this._node = null;
                this._domNodeDisposalCallback = null;
                ko.exportProperty(this, 'dispose', this.dispose);
                ko.exportProperty(this, 'disposeWhenNodeIsRemoved', this.disposeWhenNodeIsRemoved);
            };
            ko.subscription.prototype.dispose = function () {
                var self = this;
                if (!self._isDisposed) {
                    if (self._domNodeDisposalCallback) {
                        ko.utils.domNodeDisposal.removeDisposeCallback(self._node, self._domNodeDisposalCallback);
                    }
                    self._isDisposed = true;
                    self._disposeCallback();

                    self._target = self._callback = self._disposeCallback = self._node = self._domNodeDisposalCallback = null;
                }
            };
            ko.subscription.prototype.disposeWhenNodeIsRemoved = function (node) {
                this._node = node;
                ko.utils.domNodeDisposal.addDisposeCallback(node, this._domNodeDisposalCallback = this.dispose.bind(this));
            };

            ko.subscribable = function () {
                ko.utils.setPrototypeOfOrExtend(this, ko_subscribable_fn);
                ko_subscribable_fn.init(this);
            }

            var defaultEvent = "change";

            // Moved out of "limit" to avoid the extra closure
            function limitNotifySubscribers(value, event) {
                if (!event || event === defaultEvent) {
                    this._limitChange(value);
                } else if (event === 'beforeChange') {
                    this._limitBeforeChange(value);
                } else {
                    this._origNotifySubscribers(value, event);
                }
            }

            var ko_subscribable_fn = {
                init: function (instance) {
                    instance._subscriptions = { "change": [] };
                    instance._versionNumber = 1;
                },

                subscribe: function (callback, callbackTarget, event) {
                    var self = this;

                    event = event || defaultEvent;
                    var boundCallback = callbackTarget ? callback.bind(callbackTarget) : callback;

                    var subscription = new ko.subscription(self, boundCallback, function () {
                        ko.utils.arrayRemoveItem(self._subscriptions[event], subscription);
                        if (self.afterSubscriptionRemove)
                            self.afterSubscriptionRemove(event);
                    });

                    if (self.beforeSubscriptionAdd)
                        self.beforeSubscriptionAdd(event);

                    if (!self._subscriptions[event])
                        self._subscriptions[event] = [];
                    self._subscriptions[event].push(subscription);

                    return subscription;
                },

                "notifySubscribers": function (valueToNotify, event) {
                    event = event || defaultEvent;
                    if (event === defaultEvent) {
                        this.updateVersion();
                    }
                    if (this.hasSubscriptionsForEvent(event)) {
                        var subs = event === defaultEvent && this._changeSubscriptions || this._subscriptions[event].slice(0);
                        try {
                            ko.dependencyDetection.begin(); // Begin suppressing dependency detection (by setting the top frame to undefined)
                            for (var i = 0, subscription; subscription = subs[i]; ++i) {
                                // In case a subscription was disposed during the arrayForEach cycle, check
                                // for isDisposed on each subscription before invoking its callback
                                if (!subscription._isDisposed)
                                    subscription._callback(valueToNotify);
                            }
                        } finally {
                            ko.dependencyDetection.end(); // End suppressing dependency detection
                        }
                    }
                },

                getVersion: function () {
                    return this._versionNumber;
                },

                hasChanged: function (versionToCheck) {
                    return this.getVersion() !== versionToCheck;
                },

                updateVersion: function () {
                    ++this._versionNumber;
                },

                limit: function (limitFunction) {
                    var self = this, selfIsObservable = ko.isObservable(self),
                        ignoreBeforeChange, notifyNextChange, previousValue, pendingValue, didUpdate,
                        beforeChange = 'beforeChange';

                    if (!self._origNotifySubscribers) {
                        self._origNotifySubscribers = self["notifySubscribers"];
                        self["notifySubscribers"] = limitNotifySubscribers;
                    }

                    var finish = limitFunction(function () {
                        self._notificationIsPending = false;

                        // If an observable provided a reference to itself, access it to get the latest value.
                        // This allows computed observables to delay calculating their value until needed.
                        if (selfIsObservable && pendingValue === self) {
                            pendingValue = self._evalIfChanged ? self._evalIfChanged() : self();
                        }
                        var shouldNotify = notifyNextChange || (didUpdate && self.isDifferent(previousValue, pendingValue));

                        didUpdate = notifyNextChange = ignoreBeforeChange = false;

                        if (shouldNotify) {
                            self._origNotifySubscribers(previousValue = pendingValue);
                        }
                    });

                    self._limitChange = function (value, isDirty) {
                        if (!isDirty || !self._notificationIsPending) {
                            didUpdate = !isDirty;
                        }
                        self._changeSubscriptions = self._subscriptions[defaultEvent].slice(0);
                        self._notificationIsPending = ignoreBeforeChange = true;
                        pendingValue = value;
                        finish();
                    };
                    self._limitBeforeChange = function (value) {
                        if (!ignoreBeforeChange) {
                            previousValue = value;
                            self._origNotifySubscribers(value, beforeChange);
                        }
                    };
                    self._recordUpdate = function () {
                        didUpdate = true;
                    };
                    self._notifyNextChangeIfValueIsDifferent = function () {
                        if (self.isDifferent(previousValue, self.peek(true /*evaluate*/))) {
                            notifyNextChange = true;
                        }
                    };
                },

                hasSubscriptionsForEvent: function (event) {
                    return this._subscriptions[event] && this._subscriptions[event].length;
                },

                getSubscriptionsCount: function (event) {
                    if (event) {
                        return this._subscriptions[event] && this._subscriptions[event].length || 0;
                    } else {
                        var total = 0;
                        ko.utils.objectForEach(this._subscriptions, function (eventName, subscriptions) {
                            if (eventName !== 'dirty')
                                total += subscriptions.length;
                        });
                        return total;
                    }
                },

                isDifferent: function (oldValue, newValue) {
                    return !this['equalityComparer'] || !this['equalityComparer'](oldValue, newValue);
                },

                toString: function () {
                    return '[object Object]'
                },

                extend: applyExtenders
            };

            ko.exportProperty(ko_subscribable_fn, 'init', ko_subscribable_fn.init);
            ko.exportProperty(ko_subscribable_fn, 'subscribe', ko_subscribable_fn.subscribe);
            ko.exportProperty(ko_subscribable_fn, 'extend', ko_subscribable_fn.extend);
            ko.exportProperty(ko_subscribable_fn, 'getSubscriptionsCount', ko_subscribable_fn.getSubscriptionsCount);

            // For browsers that support proto assignment, we overwrite the prototype of each
            // observable instance. Since observables are functions, we need Function.prototype
            // to still be in the prototype chain.
            if (ko.utils.canSetPrototype) {
                ko.utils.setPrototypeOf(ko_subscribable_fn, Function.prototype);
            }

            ko.subscribable['fn'] = ko_subscribable_fn;


            ko.isSubscribable = function (instance) {
                return instance != null && typeof instance.subscribe == "function" && typeof instance["notifySubscribers"] == "function";
            };

            ko.exportSymbol('subscribable', ko.subscribable);
            ko.exportSymbol('isSubscribable', ko.isSubscribable);

            ko.computedContext = ko.dependencyDetection = (function () {
                var outerFrames = [],
                    currentFrame,
                    lastId = 0;

                // Return a unique ID that can be assigned to an observable for dependency tracking.
                // Theoretically, you could eventually overflow the number storage size, resulting
                // in duplicate IDs. But in JavaScript, the largest exact integral value is 2^53
                // or 9,007,199,254,740,992. If you created 1,000,000 IDs per second, it would
                // take over 285 years to reach that number.
                // Reference http://blog.vjeux.com/2010/javascript/javascript-max_int-number-limits.html
                function getId() {
                    return ++lastId;
                }

                function begin(options) {
                    outerFrames.push(currentFrame);
                    currentFrame = options;
                }

                function end() {
                    currentFrame = outerFrames.pop();
                }

                return {
                    begin: begin,

                    end: end,

                    registerDependency: function (subscribable) {
                        if (currentFrame) {
                            if (!ko.isSubscribable(subscribable))
                                throw new Error("Only subscribable things can act as dependencies");
                            currentFrame.callback.call(currentFrame.callbackTarget, subscribable, subscribable._id || (subscribable._id = getId()));
                        }
                    },

                    ignore: function (callback, callbackTarget, callbackArgs) {
                        try {
                            begin();
                            return callback.apply(callbackTarget, callbackArgs || []);
                        } finally {
                            end();
                        }
                    },

                    getDependenciesCount: function () {
                        if (currentFrame)
                            return currentFrame.computed.getDependenciesCount();
                    },

                    getDependencies: function () {
                        if (currentFrame)
                            return currentFrame.computed.getDependencies();
                    },

                    isInitial: function () {
                        if (currentFrame)
                            return currentFrame.isInitial;
                    },

                    computed: function () {
                        if (currentFrame)
                            return currentFrame.computed;
                    }
                };
            })();

            ko.exportSymbol('computedContext', ko.computedContext);
            ko.exportSymbol('computedContext.getDependenciesCount', ko.computedContext.getDependenciesCount);
            ko.exportSymbol('computedContext.getDependencies', ko.computedContext.getDependencies);
            ko.exportSymbol('computedContext.isInitial', ko.computedContext.isInitial);
            ko.exportSymbol('computedContext.registerDependency', ko.computedContext.registerDependency);

            ko.exportSymbol('ignoreDependencies', ko.ignoreDependencies = ko.dependencyDetection.ignore);
            var observableLatestValue = ko.utils.createSymbolOrString('_latestValue');

            ko.observable = function (initialValue) {
                function observable() {
                    if (arguments.length > 0) {
                        // Write

                        // Ignore writes if the value hasn't changed
                        if (observable.isDifferent(observable[observableLatestValue], arguments[0])) {
                            observable.valueWillMutate();
                            observable[observableLatestValue] = arguments[0];
                            observable.valueHasMutated();
                        }
                        return this; // Permits chained assignments
                    }
                    else {
                        // Read
                        ko.dependencyDetection.registerDependency(observable); // The caller only needs to be notified of changes if they did a "read" operation
                        return observable[observableLatestValue];
                    }
                }

                observable[observableLatestValue] = initialValue;

                // Inherit from 'subscribable'
                if (!ko.utils.canSetPrototype) {
                    // 'subscribable' won't be on the prototype chain unless we put it there directly
                    ko.utils.extend(observable, ko.subscribable['fn']);
                }
                ko.subscribable['fn'].init(observable);

                // Inherit from 'observable'
                ko.utils.setPrototypeOfOrExtend(observable, observableFn);

                if (ko.options['deferUpdates']) {
                    ko.extenders['deferred'](observable, true);
                }

                return observable;
            }

            // Define prototype for observables
            var observableFn = {
                'equalityComparer': valuesArePrimitiveAndEqual,
                peek: function () { return this[observableLatestValue]; },
                valueHasMutated: function () {
                    this['notifySubscribers'](this[observableLatestValue], 'spectate');
                    this['notifySubscribers'](this[observableLatestValue]);
                },
                valueWillMutate: function () { this['notifySubscribers'](this[observableLatestValue], 'beforeChange'); }
            };

            // Note that for browsers that don't support proto assignment, the
            // inheritance chain is created manually in the ko.observable constructor
            if (ko.utils.canSetPrototype) {
                ko.utils.setPrototypeOf(observableFn, ko.subscribable['fn']);
            }

            var protoProperty = ko.observable.protoProperty = '__ko_proto__';
            observableFn[protoProperty] = ko.observable;

            ko.isObservable = function (instance) {
                var proto = typeof instance == 'function' && instance[protoProperty];
                if (proto && proto !== observableFn[protoProperty] && proto !== ko.computed['fn'][protoProperty]) {
                    throw Error("Invalid object that looks like an observable; possibly from another Knockout instance");
                }
                return !!proto;
            };

            ko.isWriteableObservable = function (instance) {
                return (typeof instance == 'function' && (
                    (instance[protoProperty] === observableFn[protoProperty]) ||  // Observable
                    (instance[protoProperty] === ko.computed['fn'][protoProperty] && instance.hasWriteFunction)));   // Writable computed observable
            };

            ko.exportSymbol('observable', ko.observable);
            ko.exportSymbol('isObservable', ko.isObservable);
            ko.exportSymbol('isWriteableObservable', ko.isWriteableObservable);
            ko.exportSymbol('isWritableObservable', ko.isWriteableObservable);
            ko.exportSymbol('observable.fn', observableFn);
            ko.exportProperty(observableFn, 'peek', observableFn.peek);
            ko.exportProperty(observableFn, 'valueHasMutated', observableFn.valueHasMutated);
            ko.exportProperty(observableFn, 'valueWillMutate', observableFn.valueWillMutate);
            ko.observableArray = function (initialValues) {
                initialValues = initialValues || [];

                if (typeof initialValues != 'object' || !('length' in initialValues))
                    throw new Error("The argument passed when initializing an observable array must be an array, or null, or undefined.");

                var result = ko.observable(initialValues);
                ko.utils.setPrototypeOfOrExtend(result, ko.observableArray['fn']);
                return result.extend({ 'trackArrayChanges': true });
            };

            ko.observableArray['fn'] = {
                'remove': function (valueOrPredicate) {
                    var underlyingArray = this.peek();
                    var removedValues = [];
                    var predicate = typeof valueOrPredicate == "function" && !ko.isObservable(valueOrPredicate) ? valueOrPredicate : function (value) { return value === valueOrPredicate; };
                    for (var i = 0; i < underlyingArray.length; i++) {
                        var value = underlyingArray[i];
                        if (predicate(value)) {
                            if (removedValues.length === 0) {
                                this.valueWillMutate();
                            }
                            if (underlyingArray[i] !== value) {
                                throw Error("Array modified during remove; cannot remove item");
                            }
                            removedValues.push(value);
                            underlyingArray.splice(i, 1);
                            i--;
                        }
                    }
                    if (removedValues.length) {
                        this.valueHasMutated();
                    }
                    return removedValues;
                },

                'removeAll': function (arrayOfValues) {
                    // If you passed zero args, we remove everything
                    if (arrayOfValues === undefined) {
                        var underlyingArray = this.peek();
                        var allValues = underlyingArray.slice(0);
                        this.valueWillMutate();
                        underlyingArray.splice(0, underlyingArray.length);
                        this.valueHasMutated();
                        return allValues;
                    }
                    // If you passed an arg, we interpret it as an array of entries to remove
                    if (!arrayOfValues)
                        return [];
                    return this['remove'](function (value) {
                        return ko.utils.arrayIndexOf(arrayOfValues, value) >= 0;
                    });
                },

                'destroy': function (valueOrPredicate) {
                    var underlyingArray = this.peek();
                    var predicate = typeof valueOrPredicate == "function" && !ko.isObservable(valueOrPredicate) ? valueOrPredicate : function (value) { return value === valueOrPredicate; };
                    this.valueWillMutate();
                    for (var i = underlyingArray.length - 1; i >= 0; i--) {
                        var value = underlyingArray[i];
                        if (predicate(value))
                            value["_destroy"] = true;
                    }
                    this.valueHasMutated();
                },

                'destroyAll': function (arrayOfValues) {
                    // If you passed zero args, we destroy everything
                    if (arrayOfValues === undefined)
                        return this['destroy'](function () { return true });

                    // If you passed an arg, we interpret it as an array of entries to destroy
                    if (!arrayOfValues)
                        return [];
                    return this['destroy'](function (value) {
                        return ko.utils.arrayIndexOf(arrayOfValues, value) >= 0;
                    });
                },

                'indexOf': function (item) {
                    var underlyingArray = this();
                    return ko.utils.arrayIndexOf(underlyingArray, item);
                },

                'replace': function (oldItem, newItem) {
                    var index = this['indexOf'](oldItem);
                    if (index >= 0) {
                        this.valueWillMutate();
                        this.peek()[index] = newItem;
                        this.valueHasMutated();
                    }
                },

                'sorted': function (compareFunction) {
                    var arrayCopy = this().slice(0);
                    return compareFunction ? arrayCopy.sort(compareFunction) : arrayCopy.sort();
                },

                'reversed': function () {
                    return this().slice(0).reverse();
                }
            };

            // Note that for browsers that don't support proto assignment, the
            // inheritance chain is created manually in the ko.observableArray constructor
            if (ko.utils.canSetPrototype) {
                ko.utils.setPrototypeOf(ko.observableArray['fn'], ko.observable['fn']);
            }

            // Populate ko.observableArray.fn with read/write functions from native arrays
            // Important: Do not add any additional functions here that may reasonably be used to *read* data from the array
            // because we'll eval them without causing subscriptions, so ko.computed output could end up getting stale
            ko.utils.arrayForEach(["pop", "push", "reverse", "shift", "sort", "splice", "unshift"], function (methodName) {
                ko.observableArray['fn'][methodName] = function () {
                    // Use "peek" to avoid creating a subscription in any computed that we're executing in the context of
                    // (for consistency with mutating regular observables)
                    var underlyingArray = this.peek();
                    this.valueWillMutate();
                    this.cacheDiffForKnownOperation(underlyingArray, methodName, arguments);
                    var methodCallResult = underlyingArray[methodName].apply(underlyingArray, arguments);
                    this.valueHasMutated();
                    // The native sort and reverse methods return a reference to the array, but it makes more sense to return the observable array instead.
                    return methodCallResult === underlyingArray ? this : methodCallResult;
                };
            });

            // Populate ko.observableArray.fn with read-only functions from native arrays
            ko.utils.arrayForEach(["slice"], function (methodName) {
                ko.observableArray['fn'][methodName] = function () {
                    var underlyingArray = this();
                    return underlyingArray[methodName].apply(underlyingArray, arguments);
                };
            });

            ko.isObservableArray = function (instance) {
                return ko.isObservable(instance)
                    && typeof instance["remove"] == "function"
                    && typeof instance["push"] == "function";
            };

            ko.exportSymbol('observableArray', ko.observableArray);
            ko.exportSymbol('isObservableArray', ko.isObservableArray);
            var arrayChangeEventName = 'arrayChange';
            ko.extenders['trackArrayChanges'] = function (target, options) {
                // Use the provided options--each call to trackArrayChanges overwrites the previously set options
                target.compareArrayOptions = {};
                if (options && typeof options == "object") {
                    ko.utils.extend(target.compareArrayOptions, options);
                }
                target.compareArrayOptions['sparse'] = true;

                // Only modify the target observable once
                if (target.cacheDiffForKnownOperation) {
                    return;
                }
                var trackingChanges = false,
                    cachedDiff = null,
                    changeSubscription,
                    spectateSubscription,
                    pendingChanges = 0,
                    previousContents,
                    underlyingBeforeSubscriptionAddFunction = target.beforeSubscriptionAdd,
                    underlyingAfterSubscriptionRemoveFunction = target.afterSubscriptionRemove;

                // Watch "subscribe" calls, and for array change events, ensure change tracking is enabled
                target.beforeSubscriptionAdd = function (event) {
                    if (underlyingBeforeSubscriptionAddFunction) {
                        underlyingBeforeSubscriptionAddFunction.call(target, event);
                    }
                    if (event === arrayChangeEventName) {
                        trackChanges();
                    }
                };
                // Watch "dispose" calls, and for array change events, ensure change tracking is disabled when all are disposed
                target.afterSubscriptionRemove = function (event) {
                    if (underlyingAfterSubscriptionRemoveFunction) {
                        underlyingAfterSubscriptionRemoveFunction.call(target, event);
                    }
                    if (event === arrayChangeEventName && !target.hasSubscriptionsForEvent(arrayChangeEventName)) {
                        if (changeSubscription) {
                            changeSubscription.dispose();
                        }
                        if (spectateSubscription) {
                            spectateSubscription.dispose();
                        }
                        spectateSubscription = changeSubscription = null;
                        trackingChanges = false;
                        previousContents = undefined;
                    }
                };

                function trackChanges() {
                    if (trackingChanges) {
                        // Whenever there's a new subscription and there are pending notifications, make sure all previous
                        // subscriptions are notified of the change so that all subscriptions are in sync.
                        notifyChanges();
                        return;
                    }

                    trackingChanges = true;

                    // Track how many times the array actually changed value
                    spectateSubscription = target.subscribe(function () {
                        ++pendingChanges;
                    }, null, "spectate");

                    // Each time the array changes value, capture a clone so that on the next
                    // change it's possible to produce a diff
                    previousContents = [].concat(target.peek() || []);
                    cachedDiff = null;
                    changeSubscription = target.subscribe(notifyChanges);

                    function notifyChanges() {
                        if (pendingChanges) {
                            // Make a copy of the current contents and ensure it's an array
                            var currentContents = [].concat(target.peek() || []), changes;

                            // Compute the diff and issue notifications, but only if someone is listening
                            if (target.hasSubscriptionsForEvent(arrayChangeEventName)) {
                                changes = getChanges(previousContents, currentContents);
                            }

                            // Eliminate references to the old, removed items, so they can be GCed
                            previousContents = currentContents;
                            cachedDiff = null;
                            pendingChanges = 0;

                            if (changes && changes.length) {
                                target['notifySubscribers'](changes, arrayChangeEventName);
                            }
                        }
                    }
                }

                function getChanges(previousContents, currentContents) {
                    // We try to re-use cached diffs.
                    // The scenarios where pendingChanges > 1 are when using rate limiting or deferred updates,
                    // which without this check would not be compatible with arrayChange notifications. Normally,
                    // notifications are issued immediately so we wouldn't be queueing up more than one.
                    if (!cachedDiff || pendingChanges > 1) {
                        cachedDiff = ko.utils.compareArrays(previousContents, currentContents, target.compareArrayOptions);
                    }

                    return cachedDiff;
                }

                target.cacheDiffForKnownOperation = function (rawArray, operationName, args) {
                    // Only run if we're currently tracking changes for this observable array
                    // and there aren't any pending deferred notifications.
                    if (!trackingChanges || pendingChanges) {
                        return;
                    }
                    var diff = [],
                        arrayLength = rawArray.length,
                        argsLength = args.length,
                        offset = 0;

                    function pushDiff(status, value, index) {
                        return diff[diff.length] = { 'status': status, 'value': value, 'index': index };
                    }
                    switch (operationName) {
                        case 'push':
                            offset = arrayLength;
                        case 'unshift':
                            for (var index = 0; index < argsLength; index++) {
                                pushDiff('added', args[index], offset + index);
                            }
                            break;

                        case 'pop':
                            offset = arrayLength - 1;
                        case 'shift':
                            if (arrayLength) {
                                pushDiff('deleted', rawArray[offset], offset);
                            }
                            break;

                        case 'splice':
                            // Negative start index means 'from end of array'. After that we clamp to [0...arrayLength].
                            // See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice
                            var startIndex = Math.min(Math.max(0, args[0] < 0 ? arrayLength + args[0] : args[0]), arrayLength),
                                endDeleteIndex = argsLength === 1 ? arrayLength : Math.min(startIndex + (args[1] || 0), arrayLength),
                                endAddIndex = startIndex + argsLength - 2,
                                endIndex = Math.max(endDeleteIndex, endAddIndex),
                                additions = [], deletions = [];
                            for (var index = startIndex, argsIndex = 2; index < endIndex; ++index, ++argsIndex) {
                                if (index < endDeleteIndex)
                                    deletions.push(pushDiff('deleted', rawArray[index], index));
                                if (index < endAddIndex)
                                    additions.push(pushDiff('added', args[argsIndex], index));
                            }
                            ko.utils.findMovesInArrayComparison(deletions, additions);
                            break;

                        default:
                            return;
                    }
                    cachedDiff = diff;
                };
            };
            var computedState = ko.utils.createSymbolOrString('_state');

            ko.computed = ko.dependentObservable = function (evaluatorFunctionOrOptions, evaluatorFunctionTarget, options) {
                if (typeof evaluatorFunctionOrOptions === "object") {
                    // Single-parameter syntax - everything is on this "options" param
                    options = evaluatorFunctionOrOptions;
                } else {
                    // Multi-parameter syntax - construct the options according to the params passed
                    options = options || {};
                    if (evaluatorFunctionOrOptions) {
                        options["read"] = evaluatorFunctionOrOptions;
                    }
                }
                if (typeof options["read"] != "function")
                    throw Error("Pass a function that returns the value of the ko.computed");

                var writeFunction = options["write"];
                var state = {
                    latestValue: undefined,
                    isStale: true,
                    isDirty: true,
                    isBeingEvaluated: false,
                    suppressDisposalUntilDisposeWhenReturnsFalse: false,
                    isDisposed: false,
                    pure: false,
                    isSleeping: false,
                    readFunction: options["read"],
                    evaluatorFunctionTarget: evaluatorFunctionTarget || options["owner"],
                    disposeWhenNodeIsRemoved: options["disposeWhenNodeIsRemoved"] || options.disposeWhenNodeIsRemoved || null,
                    disposeWhen: options["disposeWhen"] || options.disposeWhen,
                    domNodeDisposalCallback: null,
                    dependencyTracking: {},
                    dependenciesCount: 0,
                    evaluationTimeoutInstance: null
                };

                function computedObservable() {
                    if (arguments.length > 0) {
                        if (typeof writeFunction === "function") {
                            // Writing a value
                            writeFunction.apply(state.evaluatorFunctionTarget, arguments);
                        } else {
                            throw new Error("Cannot write a value to a ko.computed unless you specify a 'write' option. If you wish to read the current value, don't pass any parameters.");
                        }
                        return this; // Permits chained assignments
                    } else {
                        // Reading the value
                        if (!state.isDisposed) {
                            ko.dependencyDetection.registerDependency(computedObservable);
                        }
                        if (state.isDirty || (state.isSleeping && computedObservable.haveDependenciesChanged())) {
                            computedObservable.evaluateImmediate();
                        }
                        return state.latestValue;
                    }
                }

                computedObservable[computedState] = state;
                computedObservable.hasWriteFunction = typeof writeFunction === "function";

                // Inherit from 'subscribable'
                if (!ko.utils.canSetPrototype) {
                    // 'subscribable' won't be on the prototype chain unless we put it there directly
                    ko.utils.extend(computedObservable, ko.subscribable['fn']);
                }
                ko.subscribable['fn'].init(computedObservable);

                // Inherit from 'computed'
                ko.utils.setPrototypeOfOrExtend(computedObservable, computedFn);

                if (options['pure']) {
                    state.pure = true;
                    state.isSleeping = true;     // Starts off sleeping; will awake on the first subscription
                    ko.utils.extend(computedObservable, pureComputedOverrides);
                } else if (options['deferEvaluation']) {
                    ko.utils.extend(computedObservable, deferEvaluationOverrides);
                }

                if (ko.options['deferUpdates']) {
                    ko.extenders['deferred'](computedObservable, true);
                }

                if (DEBUG) {
                    // #1731 - Aid debugging by exposing the computed's options
                    computedObservable["_options"] = options;
                }

                if (state.disposeWhenNodeIsRemoved) {
                    // Since this computed is associated with a DOM node, and we don't want to dispose the computed
                    // until the DOM node is *removed* from the document (as opposed to never having been in the document),
                    // we'll prevent disposal until "disposeWhen" first returns false.
                    state.suppressDisposalUntilDisposeWhenReturnsFalse = true;

                    // disposeWhenNodeIsRemoved: true can be used to opt into the "only dispose after first false result"
                    // behaviour even if there's no specific node to watch. In that case, clear the option so we don't try
                    // to watch for a non-node's disposal. This technique is intended for KO's internal use only and shouldn't
                    // be documented or used by application code, as it's likely to change in a future version of KO.
                    if (!state.disposeWhenNodeIsRemoved.nodeType) {
                        state.disposeWhenNodeIsRemoved = null;
                    }
                }

                // Evaluate, unless sleeping or deferEvaluation is true
                if (!state.isSleeping && !options['deferEvaluation']) {
                    computedObservable.evaluateImmediate();
                }

                // Attach a DOM node disposal callback so that the computed will be proactively disposed as soon as the node is
                // removed using ko.removeNode. But skip if isActive is false (there will never be any dependencies to dispose).
                if (state.disposeWhenNodeIsRemoved && computedObservable.isActive()) {
                    ko.utils.domNodeDisposal.addDisposeCallback(state.disposeWhenNodeIsRemoved, state.domNodeDisposalCallback = function () {
                        computedObservable.dispose();
                    });
                }

                return computedObservable;
            };

            // Utility function that disposes a given dependencyTracking entry
            function computedDisposeDependencyCallback(id, entryToDispose) {
                if (entryToDispose !== null && entryToDispose.dispose) {
                    entryToDispose.dispose();
                }
            }

            // This function gets called each time a dependency is detected while evaluating a computed.
            // It's factored out as a shared function to avoid creating unnecessary function instances during evaluation.
            function computedBeginDependencyDetectionCallback(subscribable, id) {
                var computedObservable = this.computedObservable,
                    state = computedObservable[computedState];
                if (!state.isDisposed) {
                    if (this.disposalCount && this.disposalCandidates[id]) {
                        // Don't want to dispose this subscription, as it's still being used
                        computedObservable.addDependencyTracking(id, subscribable, this.disposalCandidates[id]);
                        this.disposalCandidates[id] = null; // No need to actually delete the property - disposalCandidates is a transient object anyway
                        --this.disposalCount;
                    } else if (!state.dependencyTracking[id]) {
                        // Brand new subscription - add it
                        computedObservable.addDependencyTracking(id, subscribable, state.isSleeping ? { _target: subscribable } : computedObservable.subscribeToDependency(subscribable));
                    }
                    // If the observable we've accessed has a pending notification, ensure we get notified of the actual final value (bypass equality checks)
                    if (subscribable._notificationIsPending) {
                        subscribable._notifyNextChangeIfValueIsDifferent();
                    }
                }
            }

            var computedFn = {
                "equalityComparer": valuesArePrimitiveAndEqual,
                getDependenciesCount: function () {
                    return this[computedState].dependenciesCount;
                },
                getDependencies: function () {
                    var dependencyTracking = this[computedState].dependencyTracking, dependentObservables = [];

                    ko.utils.objectForEach(dependencyTracking, function (id, dependency) {
                        dependentObservables[dependency._order] = dependency._target;
                    });

                    return dependentObservables;
                },
                hasAncestorDependency: function (obs) {
                    if (!this[computedState].dependenciesCount) {
                        return false;
                    }
                    var dependencies = this.getDependencies();
                    if (ko.utils.arrayIndexOf(dependencies, obs) !== -1) {
                        return true;
                    }
                    return !!ko.utils.arrayFirst(dependencies, function (dep) {
                        return dep.hasAncestorDependency && dep.hasAncestorDependency(obs);
                    });
                },
                addDependencyTracking: function (id, target, trackingObj) {
                    if (this[computedState].pure && target === this) {
                        throw Error("A 'pure' computed must not be called recursively");
                    }

                    this[computedState].dependencyTracking[id] = trackingObj;
                    trackingObj._order = this[computedState].dependenciesCount++;
                    trackingObj._version = target.getVersion();
                },
                haveDependenciesChanged: function () {
                    var id, dependency, dependencyTracking = this[computedState].dependencyTracking;
                    for (id in dependencyTracking) {
                        if (Object.prototype.hasOwnProperty.call(dependencyTracking, id)) {
                            dependency = dependencyTracking[id];
                            if ((this._evalDelayed && dependency._target._notificationIsPending) || dependency._target.hasChanged(dependency._version)) {
                                return true;
                            }
                        }
                    }
                },
                markDirty: function () {
                    // Process "dirty" events if we can handle delayed notifications
                    if (this._evalDelayed && !this[computedState].isBeingEvaluated) {
                        this._evalDelayed(false /*isChange*/);
                    }
                },
                isActive: function () {
                    var state = this[computedState];
                    return state.isDirty || state.dependenciesCount > 0;
                },
                respondToChange: function () {
                    // Ignore "change" events if we've already scheduled a delayed notification
                    if (!this._notificationIsPending) {
                        this.evaluatePossiblyAsync();
                    } else if (this[computedState].isDirty) {
                        this[computedState].isStale = true;
                    }
                },
                subscribeToDependency: function (target) {
                    if (target._deferUpdates) {
                        var dirtySub = target.subscribe(this.markDirty, this, 'dirty'),
                            changeSub = target.subscribe(this.respondToChange, this);
                        return {
                            _target: target,
                            dispose: function () {
                                dirtySub.dispose();
                                changeSub.dispose();
                            }
                        };
                    } else {
                        return target.subscribe(this.evaluatePossiblyAsync, this);
                    }
                },
                evaluatePossiblyAsync: function () {
                    var computedObservable = this,
                        throttleEvaluationTimeout = computedObservable['throttleEvaluation'];
                    if (throttleEvaluationTimeout && throttleEvaluationTimeout >= 0) {
                        clearTimeout(this[computedState].evaluationTimeoutInstance);
                        this[computedState].evaluationTimeoutInstance = ko.utils.setTimeout(function () {
                            computedObservable.evaluateImmediate(true /*notifyChange*/);
                        }, throttleEvaluationTimeout);
                    } else if (computedObservable._evalDelayed) {
                        computedObservable._evalDelayed(true /*isChange*/);
                    } else {
                        computedObservable.evaluateImmediate(true /*notifyChange*/);
                    }
                },
                evaluateImmediate: function (notifyChange) {
                    var computedObservable = this,
                        state = computedObservable[computedState],
                        disposeWhen = state.disposeWhen,
                        changed = false;

                    if (state.isBeingEvaluated) {
                        // If the evaluation of a ko.computed causes side effects, it's possible that it will trigger its own re-evaluation.
                        // This is not desirable (it's hard for a developer to realise a chain of dependencies might cause this, and they almost
                        // certainly didn't intend infinite re-evaluations). So, for predictability, we simply prevent ko.computeds from causing
                        // their own re-evaluation. Further discussion at https://github.com/SteveSanderson/knockout/pull/387
                        return;
                    }

                    // Do not evaluate (and possibly capture new dependencies) if disposed
                    if (state.isDisposed) {
                        return;
                    }

                    if (state.disposeWhenNodeIsRemoved && !ko.utils.domNodeIsAttachedToDocument(state.disposeWhenNodeIsRemoved) || disposeWhen && disposeWhen()) {
                        // See comment above about suppressDisposalUntilDisposeWhenReturnsFalse
                        if (!state.suppressDisposalUntilDisposeWhenReturnsFalse) {
                            computedObservable.dispose();
                            return;
                        }
                    } else {
                        // It just did return false, so we can stop suppressing now
                        state.suppressDisposalUntilDisposeWhenReturnsFalse = false;
                    }

                    state.isBeingEvaluated = true;
                    try {
                        changed = this.evaluateImmediate_CallReadWithDependencyDetection(notifyChange);
                    } finally {
                        state.isBeingEvaluated = false;
                    }

                    return changed;
                },
                evaluateImmediate_CallReadWithDependencyDetection: function (notifyChange) {
                    // This function is really just part of the evaluateImmediate logic. You would never call it from anywhere else.
                    // Factoring it out into a separate function means it can be independent of the try/catch block in evaluateImmediate,
                    // which contributes to saving about 40% off the CPU overhead of computed evaluation (on V8 at least).

                    var computedObservable = this,
                        state = computedObservable[computedState],
                        changed = false;

                    // Initially, we assume that none of the subscriptions are still being used (i.e., all are candidates for disposal).
                    // Then, during evaluation, we cross off any that are in fact still being used.
                    var isInitial = state.pure ? undefined : !state.dependenciesCount,   // If we're evaluating when there are no previous dependencies, it must be the first time
                        dependencyDetectionContext = {
                            computedObservable: computedObservable,
                            disposalCandidates: state.dependencyTracking,
                            disposalCount: state.dependenciesCount
                        };

                    ko.dependencyDetection.begin({
                        callbackTarget: dependencyDetectionContext,
                        callback: computedBeginDependencyDetectionCallback,
                        computed: computedObservable,
                        isInitial: isInitial
                    });

                    state.dependencyTracking = {};
                    state.dependenciesCount = 0;

                    var newValue = this.evaluateImmediate_CallReadThenEndDependencyDetection(state, dependencyDetectionContext);

                    if (!state.dependenciesCount) {
                        computedObservable.dispose();
                        changed = true; // When evaluation causes a disposal, make sure all dependent computeds get notified so they'll see the new state
                    } else {
                        changed = computedObservable.isDifferent(state.latestValue, newValue);
                    }

                    if (changed) {
                        if (!state.isSleeping) {
                            computedObservable["notifySubscribers"](state.latestValue, "beforeChange");
                        } else {
                            computedObservable.updateVersion();
                        }

                        state.latestValue = newValue;
                        if (DEBUG) computedObservable._latestValue = newValue;

                        computedObservable["notifySubscribers"](state.latestValue, "spectate");

                        if (!state.isSleeping && notifyChange) {
                            computedObservable["notifySubscribers"](state.latestValue);
                        }
                        if (computedObservable._recordUpdate) {
                            computedObservable._recordUpdate();
                        }
                    }

                    if (isInitial) {
                        computedObservable["notifySubscribers"](state.latestValue, "awake");
                    }

                    return changed;
                },
                evaluateImmediate_CallReadThenEndDependencyDetection: function (state, dependencyDetectionContext) {
                    // This function is really part of the evaluateImmediate_CallReadWithDependencyDetection logic.
                    // You'd never call it from anywhere else. Factoring it out means that evaluateImmediate_CallReadWithDependencyDetection
                    // can be independent of try/finally blocks, which contributes to saving about 40% off the CPU
                    // overhead of computed evaluation (on V8 at least).

                    try {
                        var readFunction = state.readFunction;
                        return state.evaluatorFunctionTarget ? readFunction.call(state.evaluatorFunctionTarget) : readFunction();
                    } finally {
                        ko.dependencyDetection.end();

                        // For each subscription no longer being used, remove it from the active subscriptions list and dispose it
                        if (dependencyDetectionContext.disposalCount && !state.isSleeping) {
                            ko.utils.objectForEach(dependencyDetectionContext.disposalCandidates, computedDisposeDependencyCallback);
                        }

                        state.isStale = state.isDirty = false;
                    }
                },
                peek: function (evaluate) {
                    // By default, peek won't re-evaluate, except while the computed is sleeping or to get the initial value when "deferEvaluation" is set.
                    // Pass in true to evaluate if needed.
                    var state = this[computedState];
                    if ((state.isDirty && (evaluate || !state.dependenciesCount)) || (state.isSleeping && this.haveDependenciesChanged())) {
                        this.evaluateImmediate();
                    }
                    return state.latestValue;
                },
                limit: function (limitFunction) {
                    // Override the limit function with one that delays evaluation as well
                    ko.subscribable['fn'].limit.call(this, limitFunction);
                    this._evalIfChanged = function () {
                        if (!this[computedState].isSleeping) {
                            if (this[computedState].isStale) {
                                this.evaluateImmediate();
                            } else {
                                this[computedState].isDirty = false;
                            }
                        }
                        return this[computedState].latestValue;
                    };
                    this._evalDelayed = function (isChange) {
                        this._limitBeforeChange(this[computedState].latestValue);

                        // Mark as dirty
                        this[computedState].isDirty = true;
                        if (isChange) {
                            this[computedState].isStale = true;
                        }

                        // Pass the observable to the "limit" code, which will evaluate it when
                        // it's time to do the notification.
                        this._limitChange(this, !isChange /* isDirty */);
                    };
                },
                dispose: function () {
                    var state = this[computedState];
                    if (!state.isSleeping && state.dependencyTracking) {
                        ko.utils.objectForEach(state.dependencyTracking, function (id, dependency) {
                            if (dependency.dispose)
                                dependency.dispose();
                        });
                    }
                    if (state.disposeWhenNodeIsRemoved && state.domNodeDisposalCallback) {
                        ko.utils.domNodeDisposal.removeDisposeCallback(state.disposeWhenNodeIsRemoved, state.domNodeDisposalCallback);
                    }
                    state.dependencyTracking = undefined;
                    state.dependenciesCount = 0;
                    state.isDisposed = true;
                    state.isStale = false;
                    state.isDirty = false;
                    state.isSleeping = false;
                    state.disposeWhenNodeIsRemoved = undefined;
                    state.disposeWhen = undefined;
                    state.readFunction = undefined;
                    if (!this.hasWriteFunction) {
                        state.evaluatorFunctionTarget = undefined;
                    }
                }
            };

            var pureComputedOverrides = {
                beforeSubscriptionAdd: function (event) {
                    // If asleep, wake up the computed by subscribing to any dependencies.
                    var computedObservable = this,
                        state = computedObservable[computedState];
                    if (!state.isDisposed && state.isSleeping && event == 'change') {
                        state.isSleeping = false;
                        if (state.isStale || computedObservable.haveDependenciesChanged()) {
                            state.dependencyTracking = null;
                            state.dependenciesCount = 0;
                            if (computedObservable.evaluateImmediate()) {
                                computedObservable.updateVersion();
                            }
                        } else {
                            // First put the dependencies in order
                            var dependenciesOrder = [];
                            ko.utils.objectForEach(state.dependencyTracking, function (id, dependency) {
                                dependenciesOrder[dependency._order] = id;
                            });
                            // Next, subscribe to each one
                            ko.utils.arrayForEach(dependenciesOrder, function (id, order) {
                                var dependency = state.dependencyTracking[id],
                                    subscription = computedObservable.subscribeToDependency(dependency._target);
                                subscription._order = order;
                                subscription._version = dependency._version;
                                state.dependencyTracking[id] = subscription;
                            });
                            // Waking dependencies may have triggered effects
                            if (computedObservable.haveDependenciesChanged()) {
                                if (computedObservable.evaluateImmediate()) {
                                    computedObservable.updateVersion();
                                }
                            }
                        }

                        if (!state.isDisposed) {     // test since evaluating could trigger disposal
                            computedObservable["notifySubscribers"](state.latestValue, "awake");
                        }
                    }
                },
                afterSubscriptionRemove: function (event) {
                    var state = this[computedState];
                    if (!state.isDisposed && event == 'change' && !this.hasSubscriptionsForEvent('change')) {
                        ko.utils.objectForEach(state.dependencyTracking, function (id, dependency) {
                            if (dependency.dispose) {
                                state.dependencyTracking[id] = {
                                    _target: dependency._target,
                                    _order: dependency._order,
                                    _version: dependency._version
                                };
                                dependency.dispose();
                            }
                        });
                        state.isSleeping = true;
                        this["notifySubscribers"](undefined, "asleep");
                    }
                },
                getVersion: function () {
                    // Because a pure computed is not automatically updated while it is sleeping, we can't
                    // simply return the version number. Instead, we check if any of the dependencies have
                    // changed and conditionally re-evaluate the computed observable.
                    var state = this[computedState];
                    if (state.isSleeping && (state.isStale || this.haveDependenciesChanged())) {
                        this.evaluateImmediate();
                    }
                    return ko.subscribable['fn'].getVersion.call(this);
                }
            };

            var deferEvaluationOverrides = {
                beforeSubscriptionAdd: function (event) {
                    // This will force a computed with deferEvaluation to evaluate when the first subscription is registered.
                    if (event == 'change' || event == 'beforeChange') {
                        this.peek();
                    }
                }
            };

            // Note that for browsers that don't support proto assignment, the
            // inheritance chain is created manually in the ko.computed constructor
            if (ko.utils.canSetPrototype) {
                ko.utils.setPrototypeOf(computedFn, ko.subscribable['fn']);
            }

            // Set the proto values for ko.computed
            var protoProp = ko.observable.protoProperty; // == "__ko_proto__"
            computedFn[protoProp] = ko.computed;

            ko.isComputed = function (instance) {
                return (typeof instance == 'function' && instance[protoProp] === computedFn[protoProp]);
            };

            ko.isPureComputed = function (instance) {
                return ko.isComputed(instance) && instance[computedState] && instance[computedState].pure;
            };

            ko.exportSymbol('computed', ko.computed);
            ko.exportSymbol('dependentObservable', ko.computed);    // export ko.dependentObservable for backwards compatibility (1.x)
            ko.exportSymbol('isComputed', ko.isComputed);
            ko.exportSymbol('isPureComputed', ko.isPureComputed);
            ko.exportSymbol('computed.fn', computedFn);
            ko.exportProperty(computedFn, 'peek', computedFn.peek);
            ko.exportProperty(computedFn, 'dispose', computedFn.dispose);
            ko.exportProperty(computedFn, 'isActive', computedFn.isActive);
            ko.exportProperty(computedFn, 'getDependenciesCount', computedFn.getDependenciesCount);
            ko.exportProperty(computedFn, 'getDependencies', computedFn.getDependencies);

            ko.pureComputed = function (evaluatorFunctionOrOptions, evaluatorFunctionTarget) {
                if (typeof evaluatorFunctionOrOptions === 'function') {
                    return ko.computed(evaluatorFunctionOrOptions, evaluatorFunctionTarget, { 'pure': true });
                } else {
                    evaluatorFunctionOrOptions = ko.utils.extend({}, evaluatorFunctionOrOptions);   // make a copy of the parameter object
                    evaluatorFunctionOrOptions['pure'] = true;
                    return ko.computed(evaluatorFunctionOrOptions, evaluatorFunctionTarget);
                }
            }
            ko.exportSymbol('pureComputed', ko.pureComputed);

            (function () {
                var maxNestedObservableDepth = 10; // Escape the (unlikely) pathological case where an observable's current value is itself (or similar reference cycle)

                ko.toJS = function (rootObject) {
                    if (arguments.length == 0)
                        throw new Error("When calling ko.toJS, pass the object you want to convert.");

                    // We just unwrap everything at every level in the object graph
                    return mapJsObjectGraph(rootObject, function (valueToMap) {
                        // Loop because an observable's value might in turn be another observable wrapper
                        for (var i = 0; ko.isObservable(valueToMap) && (i < maxNestedObservableDepth); i++)
                            valueToMap = valueToMap();
                        return valueToMap;
                    });
                };

                ko.toJSON = function (rootObject, replacer, space) {     // replacer and space are optional
                    var plainJavaScriptObject = ko.toJS(rootObject);
                    return ko.utils.stringifyJson(plainJavaScriptObject, replacer, space);
                };

                function mapJsObjectGraph(rootObject, mapInputCallback, visitedObjects) {
                    visitedObjects = visitedObjects || new objectLookup();

                    rootObject = mapInputCallback(rootObject);
                    var canHaveProperties = (typeof rootObject == "object") && (rootObject !== null) && (rootObject !== undefined) && (!(rootObject instanceof RegExp)) && (!(rootObject instanceof Date)) && (!(rootObject instanceof String)) && (!(rootObject instanceof Number)) && (!(rootObject instanceof Boolean));
                    if (!canHaveProperties)
                        return rootObject;

                    var outputProperties = rootObject instanceof Array ? [] : {};
                    visitedObjects.save(rootObject, outputProperties);

                    visitPropertiesOrArrayEntries(rootObject, function (indexer) {
                        var propertyValue = mapInputCallback(rootObject[indexer]);

                        switch (typeof propertyValue) {
                            case "boolean":
                            case "number":
                            case "string":
                            case "function":
                                outputProperties[indexer] = propertyValue;
                                break;
                            case "object":
                            case "undefined":
                                var previouslyMappedValue = visitedObjects.get(propertyValue);
                                outputProperties[indexer] = (previouslyMappedValue !== undefined)
                                    ? previouslyMappedValue
                                    : mapJsObjectGraph(propertyValue, mapInputCallback, visitedObjects);
                                break;
                        }
                    });

                    return outputProperties;
                }

                function visitPropertiesOrArrayEntries(rootObject, visitorCallback) {
                    if (rootObject instanceof Array) {
                        for (var i = 0; i < rootObject.length; i++)
                            visitorCallback(i);

                        // For arrays, also respect toJSON property for custom mappings (fixes #278)
                        if (typeof rootObject['toJSON'] == 'function')
                            visitorCallback('toJSON');
                    } else {
                        for (var propertyName in rootObject) {
                            visitorCallback(propertyName);
                        }
                    }
                };

                function objectLookup() {
                    this.keys = [];
                    this.values = [];
                };

                objectLookup.prototype = {
                    constructor: objectLookup,
                    save: function (key, value) {
                        var existingIndex = ko.utils.arrayIndexOf(this.keys, key);
                        if (existingIndex >= 0)
                            this.values[existingIndex] = value;
                        else {
                            this.keys.push(key);
                            this.values.push(value);
                        }
                    },
                    get: function (key) {
                        var existingIndex = ko.utils.arrayIndexOf(this.keys, key);
                        return (existingIndex >= 0) ? this.values[existingIndex] : undefined;
                    }
                };
            })();

            ko.exportSymbol('toJS', ko.toJS);
            ko.exportSymbol('toJSON', ko.toJSON);
            ko.when = function (predicate, callback, context) {
                function kowhen(resolve) {
                    var observable = ko.pureComputed(predicate, context).extend({ notify: 'always' });
                    var subscription = observable.subscribe(function (value) {
                        if (value) {
                            subscription.dispose();
                            resolve(value);
                        }
                    });
                    // In case the initial value is true, process it right away
                    observable['notifySubscribers'](observable.peek());

                    return subscription;
                }
                if (typeof Promise === "function" && !callback) {
                    return new Promise(kowhen);
                } else {
                    return kowhen(callback.bind(context));
                }
            };

            ko.exportSymbol('when', ko.when);
            (function () {
                var hasDomDataExpandoProperty = '__ko__hasDomDataOptionValue__';

                // Normally, SELECT elements and their OPTIONs can only take value of type 'string' (because the values
                // are stored on DOM attributes). ko.selectExtensions provides a way for SELECTs/OPTIONs to have values
                // that are arbitrary objects. This is very convenient when implementing things like cascading dropdowns.
                ko.selectExtensions = {
                    readValue: function (element) {
                        switch (ko.utils.tagNameLower(element)) {
                            case 'option':
                                if (element[hasDomDataExpandoProperty] === true)
                                    return ko.utils.domData.get(element, ko.bindingHandlers.options.optionValueDomDataKey);
                                return ko.utils.ieVersion <= 7
                                    ? (element.getAttributeNode('value') && element.getAttributeNode('value').specified ? element.value : element.text)
                                    : element.value;
                            case 'select':
                                return element.selectedIndex >= 0 ? ko.selectExtensions.readValue(element.options[element.selectedIndex]) : undefined;
                            default:
                                return element.value;
                        }
                    },

                    writeValue: function (element, value, allowUnset) {
                        switch (ko.utils.tagNameLower(element)) {
                            case 'option':
                                if (typeof value === "string") {
                                    ko.utils.domData.set(element, ko.bindingHandlers.options.optionValueDomDataKey, undefined);
                                    if (hasDomDataExpandoProperty in element) { // IE <= 8 throws errors if you delete non-existent properties from a DOM node
                                        delete element[hasDomDataExpandoProperty];
                                    }
                                    element.value = value;
                                }
                                else {
                                    // Store arbitrary object using DomData
                                    ko.utils.domData.set(element, ko.bindingHandlers.options.optionValueDomDataKey, value);
                                    element[hasDomDataExpandoProperty] = true;

                                    // Special treatment of numbers is just for backward compatibility. KO 1.2.1 wrote numerical values to element.value.
                                    element.value = typeof value === "number" ? value : "";
                                }
                                break;
                            case 'select':
                                if (value === "" || value === null)       // A blank string or null value will select the caption
                                    value = undefined;
                                var selection = -1;
                                for (var i = 0, n = element.options.length, optionValue; i < n; ++i) {
                                    optionValue = ko.selectExtensions.readValue(element.options[i]);
                                    // Include special check to handle selecting a caption with a blank string value
                                    if (optionValue == value || (optionValue === "" && value === undefined)) {
                                        selection = i;
                                        break;
                                    }
                                }
                                if (allowUnset || selection >= 0 || (value === undefined && element.size > 1)) {
                                    element.selectedIndex = selection;
                                    if (ko.utils.ieVersion === 6) {
                                        // Workaround for IE6 bug: It won't reliably apply values to SELECT nodes during the same execution thread
                                        // right after you've changed the set of OPTION nodes on it. So for that node type, we'll schedule a second thread
                                        // to apply the value as well.
                                        ko.utils.setTimeout(function () {
                                            element.selectedIndex = selection;
                                        }, 0);
                                    }
                                }
                                break;
                            default:
                                if ((value === null) || (value === undefined))
                                    value = "";
                                element.value = value;
                                break;
                        }
                    }
                };
            })();

            ko.exportSymbol('selectExtensions', ko.selectExtensions);
            ko.exportSymbol('selectExtensions.readValue', ko.selectExtensions.readValue);
            ko.exportSymbol('selectExtensions.writeValue', ko.selectExtensions.writeValue);
            ko.expressionRewriting = (function () {
                var javaScriptReservedWords = ["true", "false", "null", "undefined"];

                // Matches something that can be assigned to--either an isolated identifier or something ending with a property accessor
                // This is designed to be simple and avoid false negatives, but could produce false positives (e.g., a+b.c).
                // This also will not properly handle nested brackets (e.g., obj1[obj2['prop']]; see #911).
                var javaScriptAssignmentTarget = /^(?:[$_a-z][$\w]*|(.+)(\.\s*[$_a-z][$\w]*|\[.+\]))$/i;

                function getWriteableValue(expression) {
                    if (ko.utils.arrayIndexOf(javaScriptReservedWords, expression) >= 0)
                        return false;
                    var match = expression.match(javaScriptAssignmentTarget);
                    return match === null ? false : match[1] ? ('Object(' + match[1] + ')' + match[2]) : expression;
                }

                // The following regular expressions will be used to split an object-literal string into tokens

                var specials = ',"\'`{}()/:[\\]',    // These characters have special meaning to the parser and must not appear in the middle of a token, except as part of a string.
                    // Create the actual regular expression by or-ing the following regex strings. The order is important.
                    bindingToken = RegExp([
                        // These match strings, either with double quotes, single quotes, or backticks
                        '"(?:\\\\.|[^"])*"',
                        "'(?:\\\\.|[^'])*'",
                        "`(?:\\\\.|[^`])*`",
                        // Match C style comments
                        "/\\*(?:[^*]|\\*+[^*/])*\\*+/",
                        // Match C++ style comments
                        "//.*\n",
                        // Match a regular expression (text enclosed by slashes), but will also match sets of divisions
                        // as a regular expression (this is handled by the parsing loop below).
                        '/(?:\\\\.|[^/])+/\w*',
                        // Match text (at least two characters) that does not contain any of the above special characters,
                        // although some of the special characters are allowed to start it (all but the colon and comma).
                        // The text can contain spaces, but leading or trailing spaces are skipped.
                        '[^\\s:,/][^' + specials + ']*[^\\s' + specials + ']',
                        // Match any non-space character not matched already. This will match colons and commas, since they're
                        // not matched by "everyThingElse", but will also match any other single character that wasn't already
                        // matched (for example: in "a: 1, b: 2", each of the non-space characters will be matched by oneNotSpace).
                        '[^\\s]'
                    ].join('|'), 'g'),

                    // Match end of previous token to determine whether a slash is a division or regex.
                    divisionLookBehind = /[\])"'A-Za-z0-9_$]+$/,
                    keywordRegexLookBehind = { 'in': 1, 'return': 1, 'typeof': 1 };

                function parseObjectLiteral(objectLiteralString) {
                    // Trim leading and trailing spaces from the string
                    var str = ko.utils.stringTrim(objectLiteralString);

                    // Trim braces '{' surrounding the whole object literal
                    if (str.charCodeAt(0) === 123) str = str.slice(1, -1);

                    // Add a newline to correctly match a C++ style comment at the end of the string and
                    // add a comma so that we don't need a separate code block to deal with the last item
                    str += "\n,";

                    // Split into tokens
                    var result = [], toks = str.match(bindingToken), key, values = [], depth = 0;

                    if (toks.length > 1) {
                        for (var i = 0, tok; tok = toks[i]; ++i) {
                            var c = tok.charCodeAt(0);
                            // A comma signals the end of a key/value pair if depth is zero
                            if (c === 44) { // ","
                                if (depth <= 0) {
                                    result.push((key && values.length) ? { key: key, value: values.join('') } : { 'unknown': key || values.join('') });
                                    key = depth = 0;
                                    values = [];
                                    continue;
                                }
                                // Simply skip the colon that separates the name and value
                            } else if (c === 58) { // ":"
                                if (!depth && !key && values.length === 1) {
                                    key = values.pop();
                                    continue;
                                }
                                // Comments: skip them
                            } else if (c === 47 && tok.length > 1 && (tok.charCodeAt(1) === 47 || tok.charCodeAt(1) === 42)) {  // "//" or "/*"
                                continue;
                                // A set of slashes is initially matched as a regular expression, but could be division
                            } else if (c === 47 && i && tok.length > 1) {  // "/"
                                // Look at the end of the previous token to determine if the slash is actually division
                                var match = toks[i - 1].match(divisionLookBehind);
                                if (match && !keywordRegexLookBehind[match[0]]) {
                                    // The slash is actually a division punctuator; re-parse the remainder of the string (not including the slash)
                                    str = str.substr(str.indexOf(tok) + 1);
                                    toks = str.match(bindingToken);
                                    i = -1;
                                    // Continue with just the slash
                                    tok = '/';
                                }
                                // Increment depth for parentheses, braces, and brackets so that interior commas are ignored
                            } else if (c === 40 || c === 123 || c === 91) { // '(', '{', '['
                                ++depth;
                            } else if (c === 41 || c === 125 || c === 93) { // ')', '}', ']'
                                --depth;
                                // The key will be the first token; if it's a string, trim the quotes
                            } else if (!key && !values.length && (c === 34 || c === 39)) { // '"', "'"
                                tok = tok.slice(1, -1);
                            }
                            values.push(tok);
                        }
                        if (depth > 0) {
                            throw Error("Unbalanced parentheses, braces, or brackets");
                        }
                    }
                    return result;
                }

                // Two-way bindings include a write function that allow the handler to update the value even if it's not an observable.
                var twoWayBindings = {};

                function preProcessBindings(bindingsStringOrKeyValueArray, bindingOptions) {
                    bindingOptions = bindingOptions || {};

                    function processKeyValue(key, val) {
                        var writableVal;
                        function callPreprocessHook(obj) {
                            return (obj && obj['preprocess']) ? (val = obj['preprocess'](val, key, processKeyValue)) : true;
                        }
                        if (!bindingParams) {
                            if (!callPreprocessHook(ko['getBindingHandler'](key)))
                                return;

                            if (twoWayBindings[key] && (writableVal = getWriteableValue(val))) {
                                // For two-way bindings, provide a write method in case the value
                                // isn't a writable observable.
                                var writeKey = typeof twoWayBindings[key] == 'string' ? twoWayBindings[key] : key;
                                propertyAccessorResultStrings.push("'" + writeKey + "':function(_z){" + writableVal + "=_z}");
                            }
                        }
                        // Values are wrapped in a function so that each value can be accessed independently
                        if (makeValueAccessors) {
                            val = 'function(){return ' + val + ' }';
                        }
                        resultStrings.push("'" + key + "':" + val);
                    }

                    var resultStrings = [],
                        propertyAccessorResultStrings = [],
                        makeValueAccessors = bindingOptions['valueAccessors'],
                        bindingParams = bindingOptions['bindingParams'],
                        keyValueArray = typeof bindingsStringOrKeyValueArray === "string" ?
                            parseObjectLiteral(bindingsStringOrKeyValueArray) : bindingsStringOrKeyValueArray;

                    ko.utils.arrayForEach(keyValueArray, function (keyValue) {
                        processKeyValue(keyValue.key || keyValue['unknown'], keyValue.value);
                    });

                    if (propertyAccessorResultStrings.length)
                        processKeyValue('_ko_property_writers', "{" + propertyAccessorResultStrings.join(",") + " }");

                    return resultStrings.join(",");
                }

                return {
                    bindingRewriteValidators: [],

                    twoWayBindings: twoWayBindings,

                    parseObjectLiteral: parseObjectLiteral,

                    preProcessBindings: preProcessBindings,

                    keyValueArrayContainsKey: function (keyValueArray, key) {
                        for (var i = 0; i < keyValueArray.length; i++)
                            if (keyValueArray[i]['key'] == key)
                                return true;
                        return false;
                    },

                    // Internal, private KO utility for updating model properties from within bindings
                    // property:            If the property being updated is (or might be) an observable, pass it here
                    //                      If it turns out to be a writable observable, it will be written to directly
                    // allBindings:         An object with a get method to retrieve bindings in the current execution context.
                    //                      This will be searched for a '_ko_property_writers' property in case you're writing to a non-observable
                    // key:                 The key identifying the property to be written. Example: for { hasFocus: myValue }, write to 'myValue' by specifying the key 'hasFocus'
                    // value:               The value to be written
                    // checkIfDifferent:    If true, and if the property being written is a writable observable, the value will only be written if
                    //                      it is !== existing value on that writable observable
                    writeValueToProperty: function (property, allBindings, key, value, checkIfDifferent) {
                        if (!property || !ko.isObservable(property)) {
                            var propWriters = allBindings.get('_ko_property_writers');
                            if (propWriters && propWriters[key])
                                propWriters[key](value);
                        } else if (ko.isWriteableObservable(property) && (!checkIfDifferent || property.peek() !== value)) {
                            property(value);
                        }
                    }
                };
            })();

            ko.exportSymbol('expressionRewriting', ko.expressionRewriting);
            ko.exportSymbol('expressionRewriting.bindingRewriteValidators', ko.expressionRewriting.bindingRewriteValidators);
            ko.exportSymbol('expressionRewriting.parseObjectLiteral', ko.expressionRewriting.parseObjectLiteral);
            ko.exportSymbol('expressionRewriting.preProcessBindings', ko.expressionRewriting.preProcessBindings);

            // Making bindings explicitly declare themselves as "two way" isn't ideal in the long term (it would be better if
            // all bindings could use an official 'property writer' API without needing to declare that they might). However,
            // since this is not, and has never been, a public API (_ko_property_writers was never documented), it's acceptable
            // as an internal implementation detail in the short term.
            // For those developers who rely on _ko_property_writers in their custom bindings, we expose _twoWayBindings as an
            // undocumented feature that makes it relatively easy to upgrade to KO 3.0. However, this is still not an official
            // public API, and we reserve the right to remove it at any time if we create a real public property writers API.
            ko.exportSymbol('expressionRewriting._twoWayBindings', ko.expressionRewriting.twoWayBindings);

            // For backward compatibility, define the following aliases. (Previously, these function names were misleading because
            // they referred to JSON specifically, even though they actually work with arbitrary JavaScript object literal expressions.)
            ko.exportSymbol('jsonExpressionRewriting', ko.expressionRewriting);
            ko.exportSymbol('jsonExpressionRewriting.insertPropertyAccessorsIntoJson', ko.expressionRewriting.preProcessBindings);
            (function () {
                // "Virtual elements" is an abstraction on top of the usual DOM API which understands the notion that comment nodes
                // may be used to represent hierarchy (in addition to the DOM's natural hierarchy).
                // If you call the DOM-manipulating functions on ko.virtualElements, you will be able to read and write the state
                // of that virtual hierarchy
                //
                // The point of all this is to support containerless templates (e.g., <!-- ko foreach:someCollection -->blah<!-- /ko -->)
                // without having to scatter special cases all over the binding and templating code.

                // IE 9 cannot reliably read the "nodeValue" property of a comment node (see https://github.com/SteveSanderson/knockout/issues/186)
                // but it does give them a nonstandard alternative property called "text" that it can read reliably. Other browsers don't have that property.
                // So, use node.text where available, and node.nodeValue elsewhere
                var commentNodesHaveTextProperty = document && document.createComment("test").text === "<!--test-->";

                var startCommentRegex = commentNodesHaveTextProperty ? /^<!--\s*ko(?:\s+([\s\S]+))?\s*-->$/ : /^\s*ko(?:\s+([\s\S]+))?\s*$/;
                var endCommentRegex = commentNodesHaveTextProperty ? /^<!--\s*\/ko\s*-->$/ : /^\s*\/ko\s*$/;
                var htmlTagsWithOptionallyClosingChildren = { 'ul': true, 'ol': true };

                function isStartComment(node) {
                    return (node.nodeType == 8) && startCommentRegex.test(commentNodesHaveTextProperty ? node.text : node.nodeValue);
                }

                function isEndComment(node) {
                    return (node.nodeType == 8) && endCommentRegex.test(commentNodesHaveTextProperty ? node.text : node.nodeValue);
                }

                function isUnmatchedEndComment(node) {
                    return isEndComment(node) && !(ko.utils.domData.get(node, matchedEndCommentDataKey));
                }

                var matchedEndCommentDataKey = "__ko_matchedEndComment__"

                function getVirtualChildren(startComment, allowUnbalanced) {
                    var currentNode = startComment;
                    var depth = 1;
                    var children = [];
                    while (currentNode = currentNode.nextSibling) {
                        if (isEndComment(currentNode)) {
                            ko.utils.domData.set(currentNode, matchedEndCommentDataKey, true);
                            depth--;
                            if (depth === 0)
                                return children;
                        }

                        children.push(currentNode);

                        if (isStartComment(currentNode))
                            depth++;
                    }
                    if (!allowUnbalanced)
                        throw new Error("Cannot find closing comment tag to match: " + startComment.nodeValue);
                    return null;
                }

                function getMatchingEndComment(startComment, allowUnbalanced) {
                    var allVirtualChildren = getVirtualChildren(startComment, allowUnbalanced);
                    if (allVirtualChildren) {
                        if (allVirtualChildren.length > 0)
                            return allVirtualChildren[allVirtualChildren.length - 1].nextSibling;
                        return startComment.nextSibling;
                    } else
                        return null; // Must have no matching end comment, and allowUnbalanced is true
                }

                function getUnbalancedChildTags(node) {
                    // e.g., from <div>OK</div><!-- ko blah --><span>Another</span>, returns: <!-- ko blah --><span>Another</span>
                    //       from <div>OK</div><!-- /ko --><!-- /ko -->,             returns: <!-- /ko --><!-- /ko -->
                    var childNode = node.firstChild, captureRemaining = null;
                    if (childNode) {
                        do {
                            if (captureRemaining)                   // We already hit an unbalanced node and are now just scooping up all subsequent nodes
                                captureRemaining.push(childNode);
                            else if (isStartComment(childNode)) {
                                var matchingEndComment = getMatchingEndComment(childNode, /* allowUnbalanced: */ true);
                                if (matchingEndComment)             // It's a balanced tag, so skip immediately to the end of this virtual set
                                    childNode = matchingEndComment;
                                else
                                    captureRemaining = [childNode]; // It's unbalanced, so start capturing from this point
                            } else if (isEndComment(childNode)) {
                                captureRemaining = [childNode];     // It's unbalanced (if it wasn't, we'd have skipped over it already), so start capturing
                            }
                        } while (childNode = childNode.nextSibling);
                    }
                    return captureRemaining;
                }

                ko.virtualElements = {
                    allowedBindings: {},

                    childNodes: function (node) {
                        return isStartComment(node) ? getVirtualChildren(node) : node.childNodes;
                    },

                    emptyNode: function (node) {
                        if (!isStartComment(node))
                            ko.utils.emptyDomNode(node);
                        else {
                            var virtualChildren = ko.virtualElements.childNodes(node);
                            for (var i = 0, j = virtualChildren.length; i < j; i++)
                                ko.removeNode(virtualChildren[i]);
                        }
                    },

                    setDomNodeChildren: function (node, childNodes) {
                        if (!isStartComment(node))
                            ko.utils.setDomNodeChildren(node, childNodes);
                        else {
                            ko.virtualElements.emptyNode(node);
                            var endCommentNode = node.nextSibling; // Must be the next sibling, as we just emptied the children
                            for (var i = 0, j = childNodes.length; i < j; i++)
                                endCommentNode.parentNode.insertBefore(childNodes[i], endCommentNode);
                        }
                    },

                    prepend: function (containerNode, nodeToPrepend) {
                        var insertBeforeNode;

                        if (isStartComment(containerNode)) {
                            // Start comments must always have a parent and at least one following sibling (the end comment)
                            insertBeforeNode = containerNode.nextSibling;
                            containerNode = containerNode.parentNode;
                        } else {
                            insertBeforeNode = containerNode.firstChild;
                        }

                        if (!insertBeforeNode) {
                            containerNode.appendChild(nodeToPrepend);
                        } else if (nodeToPrepend !== insertBeforeNode) {       // IE will sometimes crash if you try to insert a node before itself
                            containerNode.insertBefore(nodeToPrepend, insertBeforeNode);
                        }
                    },

                    insertAfter: function (containerNode, nodeToInsert, insertAfterNode) {
                        if (!insertAfterNode) {
                            ko.virtualElements.prepend(containerNode, nodeToInsert);
                        } else {
                            // Children of start comments must always have a parent and at least one following sibling (the end comment)
                            var insertBeforeNode = insertAfterNode.nextSibling;

                            if (isStartComment(containerNode)) {
                                containerNode = containerNode.parentNode;
                            }

                            if (!insertBeforeNode) {
                                containerNode.appendChild(nodeToInsert);
                            } else if (nodeToInsert !== insertBeforeNode) {       // IE will sometimes crash if you try to insert a node before itself
                                containerNode.insertBefore(nodeToInsert, insertBeforeNode);
                            }
                        }
                    },

                    firstChild: function (node) {
                        if (!isStartComment(node)) {
                            if (node.firstChild && isEndComment(node.firstChild)) {
                                throw new Error("Found invalid end comment, as the first child of " + node);
                            }
                            return node.firstChild;
                        } else if (!node.nextSibling || isEndComment(node.nextSibling)) {
                            return null;
                        } else {
                            return node.nextSibling;
                        }
                    },

                    nextSibling: function (node) {
                        if (isStartComment(node)) {
                            node = getMatchingEndComment(node);
                        }

                        if (node.nextSibling && isEndComment(node.nextSibling)) {
                            if (isUnmatchedEndComment(node.nextSibling)) {
                                throw Error("Found end comment without a matching opening comment, as child of " + node);
                            } else {
                                return null;
                            }
                        } else {
                            return node.nextSibling;
                        }
                    },

                    hasBindingValue: isStartComment,

                    virtualNodeBindingValue: function (node) {
                        var regexMatch = (commentNodesHaveTextProperty ? node.text : node.nodeValue).match(startCommentRegex);
                        return regexMatch ? regexMatch[1] : null;
                    },

                    normaliseVirtualElementDomStructure: function (elementVerified) {
                        // Workaround for https://github.com/SteveSanderson/knockout/issues/155
                        // (IE <= 8 or IE 9 quirks mode parses your HTML weirdly, treating closing </li> tags as if they don't exist, thereby moving comment nodes
                        // that are direct descendants of <ul> into the preceding <li>)
                        if (!htmlTagsWithOptionallyClosingChildren[ko.utils.tagNameLower(elementVerified)])
                            return;

                        // Scan immediate children to see if they contain unbalanced comment tags. If they do, those comment tags
                        // must be intended to appear *after* that child, so move them there.
                        var childNode = elementVerified.firstChild;
                        if (childNode) {
                            do {
                                if (childNode.nodeType === 1) {
                                    var unbalancedTags = getUnbalancedChildTags(childNode);
                                    if (unbalancedTags) {
                                        // Fix up the DOM by moving the unbalanced tags to where they most likely were intended to be placed - *after* the child
                                        var nodeToInsertBefore = childNode.nextSibling;
                                        for (var i = 0; i < unbalancedTags.length; i++) {
                                            if (nodeToInsertBefore)
                                                elementVerified.insertBefore(unbalancedTags[i], nodeToInsertBefore);
                                            else
                                                elementVerified.appendChild(unbalancedTags[i]);
                                        }
                                    }
                                }
                            } while (childNode = childNode.nextSibling);
                        }
                    }
                };
            })();
            ko.exportSymbol('virtualElements', ko.virtualElements);
            ko.exportSymbol('virtualElements.allowedBindings', ko.virtualElements.allowedBindings);
            ko.exportSymbol('virtualElements.emptyNode', ko.virtualElements.emptyNode);
            //ko.exportSymbol('virtualElements.firstChild', ko.virtualElements.firstChild);     // firstChild is not minified
            ko.exportSymbol('virtualElements.insertAfter', ko.virtualElements.insertAfter);
            //ko.exportSymbol('virtualElements.nextSibling', ko.virtualElements.nextSibling);   // nextSibling is not minified
            ko.exportSymbol('virtualElements.prepend', ko.virtualElements.prepend);
            ko.exportSymbol('virtualElements.setDomNodeChildren', ko.virtualElements.setDomNodeChildren);
            (function () {
                var defaultBindingAttributeName = "data-bind";

                ko.bindingProvider = function () {
                    this.bindingCache = {};
                };

                ko.utils.extend(ko.bindingProvider.prototype, {
                    'nodeHasBindings': function (node) {
                        switch (node.nodeType) {
                            case 1: // Element
                                return node.getAttribute(defaultBindingAttributeName) != null
                                    || ko.components['getComponentNameForNode'](node);
                            case 8: // Comment node
                                return ko.virtualElements.hasBindingValue(node);
                            default: return false;
                        }
                    },

                    'getBindings': function (node, bindingContext) {
                        var bindingsString = this['getBindingsString'](node, bindingContext),
                            parsedBindings = bindingsString ? this['parseBindingsString'](bindingsString, bindingContext, node) : null;
                        return ko.components.addBindingsForCustomElement(parsedBindings, node, bindingContext, /* valueAccessors */ false);
                    },

                    'getBindingAccessors': function (node, bindingContext) {
                        var bindingsString = this['getBindingsString'](node, bindingContext),
                            parsedBindings = bindingsString ? this['parseBindingsString'](bindingsString, bindingContext, node, { 'valueAccessors': true }) : null;
                        return ko.components.addBindingsForCustomElement(parsedBindings, node, bindingContext, /* valueAccessors */ true);
                    },

                    // The following function is only used internally by this default provider.
                    // It's not part of the interface definition for a general binding provider.
                    'getBindingsString': function (node, bindingContext) {
                        switch (node.nodeType) {
                            case 1: return node.getAttribute(defaultBindingAttributeName);   // Element
                            case 8: return ko.virtualElements.virtualNodeBindingValue(node); // Comment node
                            default: return null;
                        }
                    },

                    // The following function is only used internally by this default provider.
                    // It's not part of the interface definition for a general binding provider.
                    'parseBindingsString': function (bindingsString, bindingContext, node, options) {
                        try {
                            var bindingFunction = createBindingsStringEvaluatorViaCache(bindingsString, this.bindingCache, options);
                            return bindingFunction(bindingContext, node);
                        } catch (ex) {
                            ex.message = "Unable to parse bindings.\nBindings value: " + bindingsString + "\nMessage: " + ex.message;
                            throw ex;
                        }
                    }
                });

                ko.bindingProvider['instance'] = new ko.bindingProvider();

                function createBindingsStringEvaluatorViaCache(bindingsString, cache, options) {
                    var cacheKey = bindingsString + (options && options['valueAccessors'] || '');
                    return cache[cacheKey]
                        || (cache[cacheKey] = createBindingsStringEvaluator(bindingsString, options));
                }

                function createBindingsStringEvaluator(bindingsString, options) {
                    // Build the source for a function that evaluates "expression"
                    // For each scope variable, add an extra level of "with" nesting
                    // Example result: with(sc1) { with(sc0) { return (expression) } }
                    var rewrittenBindings = ko.expressionRewriting.preProcessBindings(bindingsString, options),
                        functionBody = "with($context){with($data||{}){return{" + rewrittenBindings + "}}}";
                    return new Function("$context", "$element", functionBody);
                }
            })();

            ko.exportSymbol('bindingProvider', ko.bindingProvider);
            (function () {
                // Hide or don't minify context properties, see https://github.com/knockout/knockout/issues/2294
                var contextSubscribable = ko.utils.createSymbolOrString('_subscribable');
                var contextAncestorBindingInfo = ko.utils.createSymbolOrString('_ancestorBindingInfo');
                var contextDataDependency = ko.utils.createSymbolOrString('_dataDependency');

                ko.bindingHandlers = {};

                // The following element types will not be recursed into during binding.
                var bindingDoesNotRecurseIntoElementTypes = {
                    // Don't want bindings that operate on text nodes to mutate <script> and <textarea> contents,
                    // because it's unexpected and a potential XSS issue.
                    // Also bindings should not operate on <template> elements since this breaks in Internet Explorer
                    // and because such elements' contents are always intended to be bound in a different context
                    // from where they appear in the document.
                    'script': true,
                    'textarea': true,
                    'template': true
                };

                // Use an overridable method for retrieving binding handlers so that plugins may support dynamically created handlers
                ko['getBindingHandler'] = function (bindingKey) {
                    return ko.bindingHandlers[bindingKey];
                };

                var inheritParentVm = {};

                // The ko.bindingContext constructor is only called directly to create the root context. For child
                // contexts, use bindingContext.createChildContext or bindingContext.extend.
                ko.bindingContext = function (dataItemOrAccessor, parentContext, dataItemAlias, extendCallback, options) {

                    // The binding context object includes static properties for the current, parent, and root view models.
                    // If a view model is actually stored in an observable, the corresponding binding context object, and
                    // any child contexts, must be updated when the view model is changed.
                    function updateContext() {
                        // Most of the time, the context will directly get a view model object, but if a function is given,
                        // we call the function to retrieve the view model. If the function accesses any observables or returns
                        // an observable, the dependency is tracked, and those observables can later cause the binding
                        // context to be updated.
                        var dataItemOrObservable = isFunc ? realDataItemOrAccessor() : realDataItemOrAccessor,
                            dataItem = ko.utils.unwrapObservable(dataItemOrObservable);

                        if (parentContext) {
                            // Copy $root and any custom properties from the parent context
                            ko.utils.extend(self, parentContext);

                            // Copy Symbol properties
                            if (contextAncestorBindingInfo in parentContext) {
                                self[contextAncestorBindingInfo] = parentContext[contextAncestorBindingInfo];
                            }
                        } else {
                            self['$parents'] = [];
                            self['$root'] = dataItem;

                            // Export 'ko' in the binding context so it will be available in bindings and templates
                            // even if 'ko' isn't exported as a global, such as when using an AMD loader.
                            // See https://github.com/SteveSanderson/knockout/issues/490
                            self['ko'] = ko;
                        }

                        self[contextSubscribable] = subscribable;

                        if (shouldInheritData) {
                            dataItem = self['$data'];
                        } else {
                            self['$rawData'] = dataItemOrObservable;
                            self['$data'] = dataItem;
                        }

                        if (dataItemAlias)
                            self[dataItemAlias] = dataItem;

                        // The extendCallback function is provided when creating a child context or extending a context.
                        // It handles the specific actions needed to finish setting up the binding context. Actions in this
                        // function could also add dependencies to this binding context.
                        if (extendCallback)
                            extendCallback(self, parentContext, dataItem);

                        // When a "parent" context is given and we don't already have a dependency on its context, register a dependency on it.
                        // Thus whenever the parent context is updated, this context will also be updated.
                        if (parentContext && parentContext[contextSubscribable] && !ko.computedContext.computed().hasAncestorDependency(parentContext[contextSubscribable])) {
                            parentContext[contextSubscribable]();
                        }

                        if (dataDependency) {
                            self[contextDataDependency] = dataDependency;
                        }

                        return self['$data'];
                    }

                    var self = this,
                        shouldInheritData = dataItemOrAccessor === inheritParentVm,
                        realDataItemOrAccessor = shouldInheritData ? undefined : dataItemOrAccessor,
                        isFunc = typeof (realDataItemOrAccessor) == "function" && !ko.isObservable(realDataItemOrAccessor),
                        nodes,
                        subscribable,
                        dataDependency = options && options['dataDependency'];

                    if (options && options['exportDependencies']) {
                        // The "exportDependencies" option means that the calling code will track any dependencies and re-create
                        // the binding context when they change.
                        updateContext();
                    } else {
                        subscribable = ko.pureComputed(updateContext);
                        subscribable.peek();

                        // At this point, the binding context has been initialized, and the "subscribable" computed observable is
                        // subscribed to any observables that were accessed in the process. If there is nothing to track, the
                        // computed will be inactive, and we can safely throw it away. If it's active, the computed is stored in
                        // the context object.
                        if (subscribable.isActive()) {
                            // Always notify because even if the model ($data) hasn't changed, other context properties might have changed
                            subscribable['equalityComparer'] = null;
                        } else {
                            self[contextSubscribable] = undefined;
                        }
                    }
                }

                // Extend the binding context hierarchy with a new view model object. If the parent context is watching
                // any observables, the new child context will automatically get a dependency on the parent context.
                // But this does not mean that the $data value of the child context will also get updated. If the child
                // view model also depends on the parent view model, you must provide a function that returns the correct
                // view model on each update.
                ko.bindingContext.prototype['createChildContext'] = function (dataItemOrAccessor, dataItemAlias, extendCallback, options) {
                    if (!options && dataItemAlias && typeof dataItemAlias == "object") {
                        options = dataItemAlias;
                        dataItemAlias = options['as'];
                        extendCallback = options['extend'];
                    }

                    if (dataItemAlias && options && options['noChildContext']) {
                        var isFunc = typeof (dataItemOrAccessor) == "function" && !ko.isObservable(dataItemOrAccessor);
                        return new ko.bindingContext(inheritParentVm, this, null, function (self) {
                            if (extendCallback)
                                extendCallback(self);
                            self[dataItemAlias] = isFunc ? dataItemOrAccessor() : dataItemOrAccessor;
                        }, options);
                    }

                    return new ko.bindingContext(dataItemOrAccessor, this, dataItemAlias, function (self, parentContext) {
                        // Extend the context hierarchy by setting the appropriate pointers
                        self['$parentContext'] = parentContext;
                        self['$parent'] = parentContext['$data'];
                        self['$parents'] = (parentContext['$parents'] || []).slice(0);
                        self['$parents'].unshift(self['$parent']);
                        if (extendCallback)
                            extendCallback(self);
                    }, options);
                };

                // Extend the binding context with new custom properties. This doesn't change the context hierarchy.
                // Similarly to "child" contexts, provide a function here to make sure that the correct values are set
                // when an observable view model is updated.
                ko.bindingContext.prototype['extend'] = function (properties, options) {
                    return new ko.bindingContext(inheritParentVm, this, null, function (self, parentContext) {
                        ko.utils.extend(self, typeof (properties) == "function" ? properties(self) : properties);
                    }, options);
                };

                var boundElementDomDataKey = ko.utils.domData.nextKey();

                function asyncContextDispose(node) {
                    var bindingInfo = ko.utils.domData.get(node, boundElementDomDataKey),
                        asyncContext = bindingInfo && bindingInfo.asyncContext;
                    if (asyncContext) {
                        bindingInfo.asyncContext = null;
                        asyncContext.notifyAncestor();
                    }
                }
                function AsyncCompleteContext(node, bindingInfo, ancestorBindingInfo) {
                    this.node = node;
                    this.bindingInfo = bindingInfo;
                    this.asyncDescendants = [];
                    this.childrenComplete = false;

                    if (!bindingInfo.asyncContext) {
                        ko.utils.domNodeDisposal.addDisposeCallback(node, asyncContextDispose);
                    }

                    if (ancestorBindingInfo && ancestorBindingInfo.asyncContext) {
                        ancestorBindingInfo.asyncContext.asyncDescendants.push(node);
                        this.ancestorBindingInfo = ancestorBindingInfo;
                    }
                }
                AsyncCompleteContext.prototype.notifyAncestor = function () {
                    if (this.ancestorBindingInfo && this.ancestorBindingInfo.asyncContext) {
                        this.ancestorBindingInfo.asyncContext.descendantComplete(this.node);
                    }
                };
                AsyncCompleteContext.prototype.descendantComplete = function (node) {
                    ko.utils.arrayRemoveItem(this.asyncDescendants, node);
                    if (!this.asyncDescendants.length && this.childrenComplete) {
                        this.completeChildren();
                    }
                };
                AsyncCompleteContext.prototype.completeChildren = function () {
                    this.childrenComplete = true;
                    if (this.bindingInfo.asyncContext && !this.asyncDescendants.length) {
                        this.bindingInfo.asyncContext = null;
                        ko.utils.domNodeDisposal.removeDisposeCallback(this.node, asyncContextDispose);
                        ko.bindingEvent.notify(this.node, ko.bindingEvent.descendantsComplete);
                        this.notifyAncestor();
                    }
                };

                ko.bindingEvent = {
                    childrenComplete: "childrenComplete",
                    descendantsComplete: "descendantsComplete",

                    subscribe: function (node, event, callback, context, options) {
                        var bindingInfo = ko.utils.domData.getOrSet(node, boundElementDomDataKey, {});
                        if (!bindingInfo.eventSubscribable) {
                            bindingInfo.eventSubscribable = new ko.subscribable;
                        }
                        if (options && options['notifyImmediately'] && bindingInfo.notifiedEvents[event]) {
                            ko.dependencyDetection.ignore(callback, context, [node]);
                        }
                        return bindingInfo.eventSubscribable.subscribe(callback, context, event);
                    },

                    notify: function (node, event) {
                        var bindingInfo = ko.utils.domData.get(node, boundElementDomDataKey);
                        if (bindingInfo) {
                            bindingInfo.notifiedEvents[event] = true;
                            if (bindingInfo.eventSubscribable) {
                                bindingInfo.eventSubscribable['notifySubscribers'](node, event);
                            }
                            if (event == ko.bindingEvent.childrenComplete) {
                                if (bindingInfo.asyncContext) {
                                    bindingInfo.asyncContext.completeChildren();
                                } else if (bindingInfo.asyncContext === undefined && bindingInfo.eventSubscribable && bindingInfo.eventSubscribable.hasSubscriptionsForEvent(ko.bindingEvent.descendantsComplete)) {
                                    // It's currently an error to register a descendantsComplete handler for a node that was never registered as completing asynchronously.
                                    // That's because without the asyncContext, we don't have a way to know that all descendants have completed.
                                    throw new Error("descendantsComplete event not supported for bindings on this node");
                                }
                            }
                        }
                    },

                    startPossiblyAsyncContentBinding: function (node, bindingContext) {
                        var bindingInfo = ko.utils.domData.getOrSet(node, boundElementDomDataKey, {});

                        if (!bindingInfo.asyncContext) {
                            bindingInfo.asyncContext = new AsyncCompleteContext(node, bindingInfo, bindingContext[contextAncestorBindingInfo]);
                        }

                        // If the provided context was already extended with this node's binding info, just return the extended context
                        if (bindingContext[contextAncestorBindingInfo] == bindingInfo) {
                            return bindingContext;
                        }

                        return bindingContext['extend'](function (ctx) {
                            ctx[contextAncestorBindingInfo] = bindingInfo;
                        });
                    }
                };

                // Returns the valueAccessor function for a binding value
                function makeValueAccessor(value) {
                    return function () {
                        return value;
                    };
                }

                // Returns the value of a valueAccessor function
                function evaluateValueAccessor(valueAccessor) {
                    return valueAccessor();
                }

                // Given a function that returns bindings, create and return a new object that contains
                // binding value-accessors functions. Each accessor function calls the original function
                // so that it always gets the latest value and all dependencies are captured. This is used
                // by ko.applyBindingsToNode and getBindingsAndMakeAccessors.
                function makeAccessorsFromFunction(callback) {
                    return ko.utils.objectMap(ko.dependencyDetection.ignore(callback), function (value, key) {
                        return function () {
                            return callback()[key];
                        };
                    });
                }

                // Given a bindings function or object, create and return a new object that contains
                // binding value-accessors functions. This is used by ko.applyBindingsToNode.
                function makeBindingAccessors(bindings, context, node) {
                    if (typeof bindings === 'function') {
                        return makeAccessorsFromFunction(bindings.bind(null, context, node));
                    } else {
                        return ko.utils.objectMap(bindings, makeValueAccessor);
                    }
                }

                // This function is used if the binding provider doesn't include a getBindingAccessors function.
                // It must be called with 'this' set to the provider instance.
                function getBindingsAndMakeAccessors(node, context) {
                    return makeAccessorsFromFunction(this['getBindings'].bind(this, node, context));
                }

                function validateThatBindingIsAllowedForVirtualElements(bindingName) {
                    var validator = ko.virtualElements.allowedBindings[bindingName];
                    if (!validator)
                        throw new Error("The binding '" + bindingName + "' cannot be used with virtual elements")
                }

                function applyBindingsToDescendantsInternal(bindingContext, elementOrVirtualElement) {
                    var nextInQueue = ko.virtualElements.firstChild(elementOrVirtualElement);

                    if (nextInQueue) {
                        var currentChild,
                            provider = ko.bindingProvider['instance'],
                            preprocessNode = provider['preprocessNode'];

                        // Preprocessing allows a binding provider to mutate a node before bindings are applied to it. For example it's
                        // possible to insert new siblings after it, and/or replace the node with a different one. This can be used to
                        // implement custom binding syntaxes, such as {{ value }} for string interpolation, or custom element types that
                        // trigger insertion of <template> contents at that point in the document.
                        if (preprocessNode) {
                            while (currentChild = nextInQueue) {
                                nextInQueue = ko.virtualElements.nextSibling(currentChild);
                                preprocessNode.call(provider, currentChild);
                            }
                            // Reset nextInQueue for the next loop
                            nextInQueue = ko.virtualElements.firstChild(elementOrVirtualElement);
                        }

                        while (currentChild = nextInQueue) {
                            // Keep a record of the next child *before* applying bindings, in case the binding removes the current child from its position
                            nextInQueue = ko.virtualElements.nextSibling(currentChild);
                            applyBindingsToNodeAndDescendantsInternal(bindingContext, currentChild);
                        }
                    }
                    ko.bindingEvent.notify(elementOrVirtualElement, ko.bindingEvent.childrenComplete);
                }

                function applyBindingsToNodeAndDescendantsInternal(bindingContext, nodeVerified) {
                    var bindingContextForDescendants = bindingContext;

                    var isElement = (nodeVerified.nodeType === 1);
                    if (isElement) // Workaround IE <= 8 HTML parsing weirdness
                        ko.virtualElements.normaliseVirtualElementDomStructure(nodeVerified);

                    // Perf optimisation: Apply bindings only if...
                    // (1) We need to store the binding info for the node (all element nodes)
                    // (2) It might have bindings (e.g., it has a data-bind attribute, or it's a marker for a containerless template)
                    var shouldApplyBindings = isElement || ko.bindingProvider['instance']['nodeHasBindings'](nodeVerified);
                    if (shouldApplyBindings)
                        bindingContextForDescendants = applyBindingsToNodeInternal(nodeVerified, null, bindingContext)['bindingContextForDescendants'];

                    if (bindingContextForDescendants && !bindingDoesNotRecurseIntoElementTypes[ko.utils.tagNameLower(nodeVerified)]) {
                        applyBindingsToDescendantsInternal(bindingContextForDescendants, nodeVerified);
                    }
                }

                function topologicalSortBindings(bindings) {
                    // Depth-first sort
                    var result = [],                // The list of key/handler pairs that we will return
                        bindingsConsidered = {},    // A temporary record of which bindings are already in 'result'
                        cyclicDependencyStack = []; // Keeps track of a depth-search so that, if there's a cycle, we know which bindings caused it
                    ko.utils.objectForEach(bindings, function pushBinding(bindingKey) {
                        if (!bindingsConsidered[bindingKey]) {
                            var binding = ko['getBindingHandler'](bindingKey);
                            if (binding) {
                                // First add dependencies (if any) of the current binding
                                if (binding['after']) {
                                    cyclicDependencyStack.push(bindingKey);
                                    ko.utils.arrayForEach(binding['after'], function (bindingDependencyKey) {
                                        if (bindings[bindingDependencyKey]) {
                                            if (ko.utils.arrayIndexOf(cyclicDependencyStack, bindingDependencyKey) !== -1) {
                                                throw Error("Cannot combine the following bindings, because they have a cyclic dependency: " + cyclicDependencyStack.join(", "));
                                            } else {
                                                pushBinding(bindingDependencyKey);
                                            }
                                        }
                                    });
                                    cyclicDependencyStack.length--;
                                }
                                // Next add the current binding
                                result.push({ key: bindingKey, handler: binding });
                            }
                            bindingsConsidered[bindingKey] = true;
                        }
                    });

                    return result;
                }

                function applyBindingsToNodeInternal(node, sourceBindings, bindingContext) {
                    var bindingInfo = ko.utils.domData.getOrSet(node, boundElementDomDataKey, {});

                    // Prevent multiple applyBindings calls for the same node, except when a binding value is specified
                    var alreadyBound = bindingInfo.alreadyBound;
                    if (!sourceBindings) {
                        if (alreadyBound) {
                            throw Error("You cannot apply bindings multiple times to the same element.");
                        }
                        bindingInfo.alreadyBound = true;
                    }
                    if (!alreadyBound) {
                        bindingInfo.context = bindingContext;
                    }
                    if (!bindingInfo.notifiedEvents) {
                        bindingInfo.notifiedEvents = {};
                    }

                    // Use bindings if given, otherwise fall back on asking the bindings provider to give us some bindings
                    var bindings;
                    if (sourceBindings && typeof sourceBindings !== 'function') {
                        bindings = sourceBindings;
                    } else {
                        var provider = ko.bindingProvider['instance'],
                            getBindings = provider['getBindingAccessors'] || getBindingsAndMakeAccessors;

                        // Get the binding from the provider within a computed observable so that we can update the bindings whenever
                        // the binding context is updated or if the binding provider accesses observables.
                        var bindingsUpdater = ko.dependentObservable(
                            function () {
                                bindings = sourceBindings ? sourceBindings(bindingContext, node) : getBindings.call(provider, node, bindingContext);
                                // Register a dependency on the binding context to support observable view models.
                                if (bindings) {
                                    if (bindingContext[contextSubscribable]) {
                                        bindingContext[contextSubscribable]();
                                    }
                                    if (bindingContext[contextDataDependency]) {
                                        bindingContext[contextDataDependency]();
                                    }
                                }
                                return bindings;
                            },
                            null, { disposeWhenNodeIsRemoved: node }
                        );

                        if (!bindings || !bindingsUpdater.isActive())
                            bindingsUpdater = null;
                    }

                    var contextToExtend = bindingContext;
                    var bindingHandlerThatControlsDescendantBindings;
                    if (bindings) {
                        // Return the value accessor for a given binding. When bindings are static (won't be updated because of a binding
                        // context update), just return the value accessor from the binding. Otherwise, return a function that always gets
                        // the latest binding value and registers a dependency on the binding updater.
                        var getValueAccessor = bindingsUpdater
                            ? function (bindingKey) {
                                return function () {
                                    return evaluateValueAccessor(bindingsUpdater()[bindingKey]);
                                };
                            } : function (bindingKey) {
                                return bindings[bindingKey];
                            };

                        // Use of allBindings as a function is maintained for backwards compatibility, but its use is deprecated
                        function allBindings() {
                            return ko.utils.objectMap(bindingsUpdater ? bindingsUpdater() : bindings, evaluateValueAccessor);
                        }
                        // The following is the 3.x allBindings API
                        allBindings['get'] = function (key) {
                            return bindings[key] && evaluateValueAccessor(getValueAccessor(key));
                        };
                        allBindings['has'] = function (key) {
                            return key in bindings;
                        };

                        if (ko.bindingEvent.childrenComplete in bindings) {
                            ko.bindingEvent.subscribe(node, ko.bindingEvent.childrenComplete, function () {
                                var callback = evaluateValueAccessor(bindings[ko.bindingEvent.childrenComplete]);
                                if (callback) {
                                    var nodes = ko.virtualElements.childNodes(node);
                                    if (nodes.length) {
                                        callback(nodes, ko.dataFor(nodes[0]));
                                    }
                                }
                            });
                        }

                        if (ko.bindingEvent.descendantsComplete in bindings) {
                            contextToExtend = ko.bindingEvent.startPossiblyAsyncContentBinding(node, bindingContext);
                            ko.bindingEvent.subscribe(node, ko.bindingEvent.descendantsComplete, function () {
                                var callback = evaluateValueAccessor(bindings[ko.bindingEvent.descendantsComplete]);
                                if (callback && ko.virtualElements.firstChild(node)) {
                                    callback(node);
                                }
                            });
                        }

                        // First put the bindings into the right order
                        var orderedBindings = topologicalSortBindings(bindings);

                        // Go through the sorted bindings, calling init and update for each
                        ko.utils.arrayForEach(orderedBindings, function (bindingKeyAndHandler) {
                            // Note that topologicalSortBindings has already filtered out any nonexistent binding handlers,
                            // so bindingKeyAndHandler.handler will always be nonnull.
                            var handlerInitFn = bindingKeyAndHandler.handler["init"],
                                handlerUpdateFn = bindingKeyAndHandler.handler["update"],
                                bindingKey = bindingKeyAndHandler.key;

                            if (node.nodeType === 8) {
                                validateThatBindingIsAllowedForVirtualElements(bindingKey);
                            }

                            try {
                                // Run init, ignoring any dependencies
                                if (typeof handlerInitFn == "function") {
                                    ko.dependencyDetection.ignore(function () {
                                        var initResult = handlerInitFn(node, getValueAccessor(bindingKey), allBindings, contextToExtend['$data'], contextToExtend);

                                        // If this binding handler claims to control descendant bindings, make a note of this
                                        if (initResult && initResult['controlsDescendantBindings']) {
                                            if (bindingHandlerThatControlsDescendantBindings !== undefined)
                                                throw new Error("Multiple bindings (" + bindingHandlerThatControlsDescendantBindings + " and " + bindingKey + ") are trying to control descendant bindings of the same element. You cannot use these bindings together on the same element.");
                                            bindingHandlerThatControlsDescendantBindings = bindingKey;
                                        }
                                    });
                                }

                                // Run update in its own computed wrapper
                                if (typeof handlerUpdateFn == "function") {
                                    ko.dependentObservable(
                                        function () {
                                            handlerUpdateFn(node, getValueAccessor(bindingKey), allBindings, contextToExtend['$data'], contextToExtend);
                                        },
                                        null,
                                        { disposeWhenNodeIsRemoved: node }
                                    );
                                }
                            } catch (ex) {
                                ex.message = "Unable to process binding \"" + bindingKey + ": " + bindings[bindingKey] + "\"\nMessage: " + ex.message;
                                throw ex;
                            }
                        });
                    }

                    var shouldBindDescendants = bindingHandlerThatControlsDescendantBindings === undefined;
                    return {
                        'shouldBindDescendants': shouldBindDescendants,
                        'bindingContextForDescendants': shouldBindDescendants && contextToExtend
                    };
                };

                ko.storedBindingContextForNode = function (node) {
                    var bindingInfo = ko.utils.domData.get(node, boundElementDomDataKey);
                    return bindingInfo && bindingInfo.context;
                }

                function getBindingContext(viewModelOrBindingContext, extendContextCallback) {
                    return viewModelOrBindingContext && (viewModelOrBindingContext instanceof ko.bindingContext)
                        ? viewModelOrBindingContext
                        : new ko.bindingContext(viewModelOrBindingContext, undefined, undefined, extendContextCallback);
                }

                ko.applyBindingAccessorsToNode = function (node, bindings, viewModelOrBindingContext) {
                    if (node.nodeType === 1) // If it's an element, workaround IE <= 8 HTML parsing weirdness
                        ko.virtualElements.normaliseVirtualElementDomStructure(node);
                    return applyBindingsToNodeInternal(node, bindings, getBindingContext(viewModelOrBindingContext));
                };

                ko.applyBindingsToNode = function (node, bindings, viewModelOrBindingContext) {
                    var context = getBindingContext(viewModelOrBindingContext);
                    return ko.applyBindingAccessorsToNode(node, makeBindingAccessors(bindings, context, node), context);
                };

                ko.applyBindingsToDescendants = function (viewModelOrBindingContext, rootNode) {
                    if (rootNode.nodeType === 1 || rootNode.nodeType === 8)
                        applyBindingsToDescendantsInternal(getBindingContext(viewModelOrBindingContext), rootNode);
                };

                ko.applyBindings = function (viewModelOrBindingContext, rootNode, extendContextCallback) {
                    // If jQuery is loaded after Knockout, we won't initially have access to it. So save it here.
                    if (!jQueryInstance && window['jQuery']) {
                        jQueryInstance = window['jQuery'];
                    }

                    if (arguments.length < 2) {
                        rootNode = document.body;
                        if (!rootNode) {
                            throw Error("ko.applyBindings: could not find document.body; has the document been loaded?");
                        }
                    } else if (!rootNode || (rootNode.nodeType !== 1 && rootNode.nodeType !== 8)) {
                        throw Error("ko.applyBindings: first parameter should be your view model; second parameter should be a DOM node");
                    }

                    applyBindingsToNodeAndDescendantsInternal(getBindingContext(viewModelOrBindingContext, extendContextCallback), rootNode);
                };

                // Retrieving binding context from arbitrary nodes
                ko.contextFor = function (node) {
                    // We can only do something meaningful for elements and comment nodes (in particular, not text nodes, as IE can't store domdata for them)
                    if (node && (node.nodeType === 1 || node.nodeType === 8)) {
                        return ko.storedBindingContextForNode(node);
                    }
                    return undefined;
                };
                ko.dataFor = function (node) {
                    var context = ko.contextFor(node);
                    return context ? context['$data'] : undefined;
                };

                ko.exportSymbol('bindingHandlers', ko.bindingHandlers);
                ko.exportSymbol('bindingEvent', ko.bindingEvent);
                ko.exportSymbol('bindingEvent.subscribe', ko.bindingEvent.subscribe);
                ko.exportSymbol('bindingEvent.startPossiblyAsyncContentBinding', ko.bindingEvent.startPossiblyAsyncContentBinding);
                ko.exportSymbol('applyBindings', ko.applyBindings);
                ko.exportSymbol('applyBindingsToDescendants', ko.applyBindingsToDescendants);
                ko.exportSymbol('applyBindingAccessorsToNode', ko.applyBindingAccessorsToNode);
                ko.exportSymbol('applyBindingsToNode', ko.applyBindingsToNode);
                ko.exportSymbol('contextFor', ko.contextFor);
                ko.exportSymbol('dataFor', ko.dataFor);
            })();
            (function (undefined) {
                var loadingSubscribablesCache = {}, // Tracks component loads that are currently in flight
                    loadedDefinitionsCache = {};    // Tracks component loads that have already completed

                ko.components = {
                    get: function (componentName, callback) {
                        var cachedDefinition = getObjectOwnProperty(loadedDefinitionsCache, componentName);
                        if (cachedDefinition) {
                            // It's already loaded and cached. Reuse the same definition object.
                            // Note that for API consistency, even cache hits complete asynchronously by default.
                            // You can bypass this by putting synchronous:true on your component config.
                            if (cachedDefinition.isSynchronousComponent) {
                                ko.dependencyDetection.ignore(function () { // See comment in loaderRegistryBehaviors.js for reasoning
                                    callback(cachedDefinition.definition);
                                });
                            } else {
                                ko.tasks.schedule(function () { callback(cachedDefinition.definition); });
                            }
                        } else {
                            // Join the loading process that is already underway, or start a new one.
                            loadComponentAndNotify(componentName, callback);
                        }
                    },

                    clearCachedDefinition: function (componentName) {
                        delete loadedDefinitionsCache[componentName];
                    },

                    _getFirstResultFromLoaders: getFirstResultFromLoaders
                };

                function getObjectOwnProperty(obj, propName) {
                    return Object.prototype.hasOwnProperty.call(obj, propName) ? obj[propName] : undefined;
                }

                function loadComponentAndNotify(componentName, callback) {
                    var subscribable = getObjectOwnProperty(loadingSubscribablesCache, componentName),
                        completedAsync;
                    if (!subscribable) {
                        // It's not started loading yet. Start loading, and when it's done, move it to loadedDefinitionsCache.
                        subscribable = loadingSubscribablesCache[componentName] = new ko.subscribable();
                        subscribable.subscribe(callback);

                        beginLoadingComponent(componentName, function (definition, config) {
                            var isSynchronousComponent = !!(config && config['synchronous']);
                            loadedDefinitionsCache[componentName] = { definition: definition, isSynchronousComponent: isSynchronousComponent };
                            delete loadingSubscribablesCache[componentName];

                            // For API consistency, all loads complete asynchronously. However we want to avoid
                            // adding an extra task schedule if it's unnecessary (i.e., the completion is already
                            // async).
                            //
                            // You can bypass the 'always asynchronous' feature by putting the synchronous:true
                            // flag on your component configuration when you register it.
                            if (completedAsync || isSynchronousComponent) {
                                // Note that notifySubscribers ignores any dependencies read within the callback.
                                // See comment in loaderRegistryBehaviors.js for reasoning
                                subscribable['notifySubscribers'](definition);
                            } else {
                                ko.tasks.schedule(function () {
                                    subscribable['notifySubscribers'](definition);
                                });
                            }
                        });
                        completedAsync = true;
                    } else {
                        subscribable.subscribe(callback);
                    }
                }

                function beginLoadingComponent(componentName, callback) {
                    getFirstResultFromLoaders('getConfig', [componentName], function (config) {
                        if (config) {
                            // We have a config, so now load its definition
                            getFirstResultFromLoaders('loadComponent', [componentName, config], function (definition) {
                                callback(definition, config);
                            });
                        } else {
                            // The component has no config - it's unknown to all the loaders.
                            // Note that this is not an error (e.g., a module loading error) - that would abort the
                            // process and this callback would not run. For this callback to run, all loaders must
                            // have confirmed they don't know about this component.
                            callback(null, null);
                        }
                    });
                }

                function getFirstResultFromLoaders(methodName, argsExceptCallback, callback, candidateLoaders) {
                    // On the first call in the stack, start with the full set of loaders
                    if (!candidateLoaders) {
                        candidateLoaders = ko.components['loaders'].slice(0); // Use a copy, because we'll be mutating this array
                    }

                    // Try the next candidate
                    var currentCandidateLoader = candidateLoaders.shift();
                    if (currentCandidateLoader) {
                        var methodInstance = currentCandidateLoader[methodName];
                        if (methodInstance) {
                            var wasAborted = false,
                                synchronousReturnValue = methodInstance.apply(currentCandidateLoader, argsExceptCallback.concat(function (result) {
                                    if (wasAborted) {
                                        callback(null);
                                    } else if (result !== null) {
                                        // This candidate returned a value. Use it.
                                        callback(result);
                                    } else {
                                        // Try the next candidate
                                        getFirstResultFromLoaders(methodName, argsExceptCallback, callback, candidateLoaders);
                                    }
                                }));

                            // Currently, loaders may not return anything synchronously. This leaves open the possibility
                            // that we'll extend the API to support synchronous return values in the future. It won't be
                            // a breaking change, because currently no loader is allowed to return anything except undefined.
                            if (synchronousReturnValue !== undefined) {
                                wasAborted = true;

                                // Method to suppress exceptions will remain undocumented. This is only to keep
                                // KO's specs running tidily, since we can observe the loading got aborted without
                                // having exceptions cluttering up the console too.
                                if (!currentCandidateLoader['suppressLoaderExceptions']) {
                                    throw new Error('Component loaders must supply values by invoking the callback, not by returning values synchronously.');
                                }
                            }
                        } else {
                            // This candidate doesn't have the relevant handler. Synchronously move on to the next one.
                            getFirstResultFromLoaders(methodName, argsExceptCallback, callback, candidateLoaders);
                        }
                    } else {
                        // No candidates returned a value
                        callback(null);
                    }
                }

                // Reference the loaders via string name so it's possible for developers
                // to replace the whole array by assigning to ko.components.loaders
                ko.components['loaders'] = [];

                ko.exportSymbol('components', ko.components);
                ko.exportSymbol('components.get', ko.components.get);
                ko.exportSymbol('components.clearCachedDefinition', ko.components.clearCachedDefinition);
            })();
            (function (undefined) {

                // The default loader is responsible for two things:
                // 1. Maintaining the default in-memory registry of component configuration objects
                //    (i.e., the thing you're writing to when you call ko.components.register(someName, ...))
                // 2. Answering requests for components by fetching configuration objects
                //    from that default in-memory registry and resolving them into standard
                //    component definition objects (of the form { createViewModel: ..., template: ... })
                // Custom loaders may override either of these facilities, i.e.,
                // 1. To supply configuration objects from some other source (e.g., conventions)
                // 2. Or, to resolve configuration objects by loading viewmodels/templates via arbitrary logic.

                var defaultConfigRegistry = {};

                ko.components.register = function (componentName, config) {
                    if (!config) {
                        throw new Error('Invalid configuration for ' + componentName);
                    }

                    if (ko.components.isRegistered(componentName)) {
                        throw new Error('Component ' + componentName + ' is already registered');
                    }

                    defaultConfigRegistry[componentName] = config;
                };

                ko.components.isRegistered = function (componentName) {
                    return Object.prototype.hasOwnProperty.call(defaultConfigRegistry, componentName);
                };

                ko.components.unregister = function (componentName) {
                    delete defaultConfigRegistry[componentName];
                    ko.components.clearCachedDefinition(componentName);
                };

                ko.components.defaultLoader = {
                    'getConfig': function (componentName, callback) {
                        var result = ko.components.isRegistered(componentName)
                            ? defaultConfigRegistry[componentName]
                            : null;
                        callback(result);
                    },

                    'loadComponent': function (componentName, config, callback) {
                        var errorCallback = makeErrorCallback(componentName);
                        possiblyGetConfigFromAmd(errorCallback, config, function (loadedConfig) {
                            resolveConfig(componentName, errorCallback, loadedConfig, callback);
                        });
                    },

                    'loadTemplate': function (componentName, templateConfig, callback) {
                        resolveTemplate(makeErrorCallback(componentName), templateConfig, callback);
                    },

                    'loadViewModel': function (componentName, viewModelConfig, callback) {
                        resolveViewModel(makeErrorCallback(componentName), viewModelConfig, callback);
                    }
                };

                var createViewModelKey = 'createViewModel';

                // Takes a config object of the form { template: ..., viewModel: ... }, and asynchronously convert it
                // into the standard component definition format:
                //    { template: <ArrayOfDomNodes>, createViewModel: function(params, componentInfo) { ... } }.
                // Since both template and viewModel may need to be resolved asynchronously, both tasks are performed
                // in parallel, and the results joined when both are ready. We don't depend on any promises infrastructure,
                // so this is implemented manually below.
                function resolveConfig(componentName, errorCallback, config, callback) {
                    var result = {},
                        makeCallBackWhenZero = 2,
                        tryIssueCallback = function () {
                            if (--makeCallBackWhenZero === 0) {
                                callback(result);
                            }
                        },
                        templateConfig = config['template'],
                        viewModelConfig = config['viewModel'];

                    if (templateConfig) {
                        possiblyGetConfigFromAmd(errorCallback, templateConfig, function (loadedConfig) {
                            ko.components._getFirstResultFromLoaders('loadTemplate', [componentName, loadedConfig], function (resolvedTemplate) {
                                result['template'] = resolvedTemplate;
                                tryIssueCallback();
                            });
                        });
                    } else {
                        tryIssueCallback();
                    }

                    if (viewModelConfig) {
                        possiblyGetConfigFromAmd(errorCallback, viewModelConfig, function (loadedConfig) {
                            ko.components._getFirstResultFromLoaders('loadViewModel', [componentName, loadedConfig], function (resolvedViewModel) {
                                result[createViewModelKey] = resolvedViewModel;
                                tryIssueCallback();
                            });
                        });
                    } else {
                        tryIssueCallback();
                    }
                }

                function resolveTemplate(errorCallback, templateConfig, callback) {
                    if (typeof templateConfig === 'string') {
                        // Markup - parse it
                        callback(ko.utils.parseHtmlFragment(templateConfig));
                    } else if (templateConfig instanceof Array) {
                        // Assume already an array of DOM nodes - pass through unchanged
                        callback(templateConfig);
                    } else if (isDocumentFragment(templateConfig)) {
                        // Document fragment - use its child nodes
                        callback(ko.utils.makeArray(templateConfig.childNodes));
                    } else if (templateConfig['element']) {
                        var element = templateConfig['element'];
                        if (isDomElement(element)) {
                            // Element instance - copy its child nodes
                            callback(cloneNodesFromTemplateSourceElement(element));
                        } else if (typeof element === 'string') {
                            // Element ID - find it, then copy its child nodes
                            var elemInstance = document.getElementById(element);
                            if (elemInstance) {
                                callback(cloneNodesFromTemplateSourceElement(elemInstance));
                            } else {
                                errorCallback('Cannot find element with ID ' + element);
                            }
                        } else {
                            errorCallback('Unknown element type: ' + element);
                        }
                    } else {
                        errorCallback('Unknown template value: ' + templateConfig);
                    }
                }

                function resolveViewModel(errorCallback, viewModelConfig, callback) {
                    if (typeof viewModelConfig === 'function') {
                        // Constructor - convert to standard factory function format
                        // By design, this does *not* supply componentInfo to the constructor, as the intent is that
                        // componentInfo contains non-viewmodel data (e.g., the component's element) that should only
                        // be used in factory functions, not viewmodel constructors.
                        callback(function (params /*, componentInfo */) {
                            return new viewModelConfig(params);
                        });
                    } else if (typeof viewModelConfig[createViewModelKey] === 'function') {
                        // Already a factory function - use it as-is
                        callback(viewModelConfig[createViewModelKey]);
                    } else if ('instance' in viewModelConfig) {
                        // Fixed object instance - promote to createViewModel format for API consistency
                        var fixedInstance = viewModelConfig['instance'];
                        callback(function (params, componentInfo) {
                            return fixedInstance;
                        });
                    } else if ('viewModel' in viewModelConfig) {
                        // Resolved AMD module whose value is of the form { viewModel: ... }
                        resolveViewModel(errorCallback, viewModelConfig['viewModel'], callback);
                    } else {
                        errorCallback('Unknown viewModel value: ' + viewModelConfig);
                    }
                }

                function cloneNodesFromTemplateSourceElement(elemInstance) {
                    switch (ko.utils.tagNameLower(elemInstance)) {
                        case 'script':
                            return ko.utils.parseHtmlFragment(elemInstance.text);
                        case 'textarea':
                            return ko.utils.parseHtmlFragment(elemInstance.value);
                        case 'template':
                            // For browsers with proper <template> element support (i.e., where the .content property
                            // gives a document fragment), use that document fragment.
                            if (isDocumentFragment(elemInstance.content)) {
                                return ko.utils.cloneNodes(elemInstance.content.childNodes);
                            }
                    }

                    // Regular elements such as <div>, and <template> elements on old browsers that don't really
                    // understand <template> and just treat it as a regular container
                    return ko.utils.cloneNodes(elemInstance.childNodes);
                }

                function isDomElement(obj) {
                    if (window['HTMLElement']) {
                        return obj instanceof HTMLElement;
                    } else {
                        return obj && obj.tagName && obj.nodeType === 1;
                    }
                }

                function isDocumentFragment(obj) {
                    if (window['DocumentFragment']) {
                        return obj instanceof DocumentFragment;
                    } else {
                        return obj && obj.nodeType === 11;
                    }
                }

                function possiblyGetConfigFromAmd(errorCallback, config, callback) {
                    if (typeof config['require'] === 'string') {
                        // The config is the value of an AMD module
                        if (amdRequire || window['require']) {
                            (amdRequire || window['require'])([config['require']], function (module) {
                                if (module && typeof module === 'object' && module.__esModule && module.default) {
                                    module = module.default;
                                }
                                callback(module);
                            });
                        } else {
                            errorCallback('Uses require, but no AMD loader is present');
                        }
                    } else {
                        callback(config);
                    }
                }

                function makeErrorCallback(componentName) {
                    return function (message) {
                        throw new Error('Component \'' + componentName + '\': ' + message);
                    };
                }

                ko.exportSymbol('components.register', ko.components.register);
                ko.exportSymbol('components.isRegistered', ko.components.isRegistered);
                ko.exportSymbol('components.unregister', ko.components.unregister);

                // Expose the default loader so that developers can directly ask it for configuration
                // or to resolve configuration
                ko.exportSymbol('components.defaultLoader', ko.components.defaultLoader);

                // By default, the default loader is the only registered component loader
                ko.components['loaders'].push(ko.components.defaultLoader);

                // Privately expose the underlying config registry for use in old-IE shim
                ko.components._allRegisteredComponents = defaultConfigRegistry;
            })();
            (function (undefined) {
                // Overridable API for determining which component name applies to a given node. By overriding this,
                // you can for example map specific tagNames to components that are not preregistered.
                ko.components['getComponentNameForNode'] = function (node) {
                    var tagNameLower = ko.utils.tagNameLower(node);
                    if (ko.components.isRegistered(tagNameLower)) {
                        // Try to determine that this node can be considered a *custom* element; see https://github.com/knockout/knockout/issues/1603
                        if (tagNameLower.indexOf('-') != -1 || ('' + node) == "[object HTMLUnknownElement]" || (ko.utils.ieVersion <= 8 && node.tagName === tagNameLower)) {
                            return tagNameLower;
                        }
                    }
                };

                ko.components.addBindingsForCustomElement = function (allBindings, node, bindingContext, valueAccessors) {
                    // Determine if it's really a custom element matching a component
                    if (node.nodeType === 1) {
                        var componentName = ko.components['getComponentNameForNode'](node);
                        if (componentName) {
                            // It does represent a component, so add a component binding for it
                            allBindings = allBindings || {};

                            if (allBindings['component']) {
                                // Avoid silently overwriting some other 'component' binding that may already be on the element
                                throw new Error('Cannot use the "component" binding on a custom element matching a component');
                            }

                            var componentBindingValue = { 'name': componentName, 'params': getComponentParamsFromCustomElement(node, bindingContext) };

                            allBindings['component'] = valueAccessors
                                ? function () { return componentBindingValue; }
                                : componentBindingValue;
                        }
                    }

                    return allBindings;
                }

                var nativeBindingProviderInstance = new ko.bindingProvider();

                function getComponentParamsFromCustomElement(elem, bindingContext) {
                    var paramsAttribute = elem.getAttribute('params');

                    if (paramsAttribute) {
                        var params = nativeBindingProviderInstance['parseBindingsString'](paramsAttribute, bindingContext, elem, { 'valueAccessors': true, 'bindingParams': true }),
                            rawParamComputedValues = ko.utils.objectMap(params, function (paramValue, paramName) {
                                return ko.computed(paramValue, null, { disposeWhenNodeIsRemoved: elem });
                            }),
                            result = ko.utils.objectMap(rawParamComputedValues, function (paramValueComputed, paramName) {
                                var paramValue = paramValueComputed.peek();
                                // Does the evaluation of the parameter value unwrap any observables?
                                if (!paramValueComputed.isActive()) {
                                    // No it doesn't, so there's no need for any computed wrapper. Just pass through the supplied value directly.
                                    // Example: "someVal: firstName, age: 123" (whether or not firstName is an observable/computed)
                                    return paramValue;
                                } else {
                                    // Yes it does. Supply a computed property that unwraps both the outer (binding expression)
                                    // level of observability, and any inner (resulting model value) level of observability.
                                    // This means the component doesn't have to worry about multiple unwrapping. If the value is a
                                    // writable observable, the computed will also be writable and pass the value on to the observable.
                                    return ko.computed({
                                        'read': function () {
                                            return ko.utils.unwrapObservable(paramValueComputed());
                                        },
                                        'write': ko.isWriteableObservable(paramValue) && function (value) {
                                            paramValueComputed()(value);
                                        },
                                        disposeWhenNodeIsRemoved: elem
                                    });
                                }
                            });

                        // Give access to the raw computeds, as long as that wouldn't overwrite any custom param also called '$raw'
                        // This is in case the developer wants to react to outer (binding) observability separately from inner
                        // (model value) observability, or in case the model value observable has subobservables.
                        if (!Object.prototype.hasOwnProperty.call(result, '$raw')) {
                            result['$raw'] = rawParamComputedValues;
                        }

                        return result;
                    } else {
                        // For consistency, absence of a "params" attribute is treated the same as the presence of
                        // any empty one. Otherwise component viewmodels need special code to check whether or not
                        // 'params' or 'params.$raw' is null/undefined before reading subproperties, which is annoying.
                        return { '$raw': {} };
                    }
                }

                // --------------------------------------------------------------------------------
                // Compatibility code for older (pre-HTML5) IE browsers

                if (ko.utils.ieVersion < 9) {
                    // Whenever you preregister a component, enable it as a custom element in the current document
                    ko.components['register'] = (function (originalFunction) {
                        return function (componentName) {
                            document.createElement(componentName); // Allows IE<9 to parse markup containing the custom element
                            return originalFunction.apply(this, arguments);
                        }
                    })(ko.components['register']);

                    // Whenever you create a document fragment, enable all preregistered component names as custom elements
                    // This is needed to make innerShiv/jQuery HTML parsing correctly handle the custom elements
                    document.createDocumentFragment = (function (originalFunction) {
                        return function () {
                            var newDocFrag = originalFunction(),
                                allComponents = ko.components._allRegisteredComponents;
                            for (var componentName in allComponents) {
                                if (Object.prototype.hasOwnProperty.call(allComponents, componentName)) {
                                    newDocFrag.createElement(componentName);
                                }
                            }
                            return newDocFrag;
                        };
                    })(document.createDocumentFragment);
                }
            })(); (function (undefined) {
                var componentLoadingOperationUniqueId = 0;

                ko.bindingHandlers['component'] = {
                    'init': function (element, valueAccessor, ignored1, ignored2, bindingContext) {
                        var currentViewModel,
                            currentLoadingOperationId,
                            afterRenderSub,
                            disposeAssociatedComponentViewModel = function () {
                                var currentViewModelDispose = currentViewModel && currentViewModel['dispose'];
                                if (typeof currentViewModelDispose === 'function') {
                                    currentViewModelDispose.call(currentViewModel);
                                }
                                if (afterRenderSub) {
                                    afterRenderSub.dispose();
                                }
                                afterRenderSub = null;
                                currentViewModel = null;
                                // Any in-flight loading operation is no longer relevant, so make sure we ignore its completion
                                currentLoadingOperationId = null;
                            },
                            originalChildNodes = ko.utils.makeArray(ko.virtualElements.childNodes(element));

                        ko.virtualElements.emptyNode(element);
                        ko.utils.domNodeDisposal.addDisposeCallback(element, disposeAssociatedComponentViewModel);

                        ko.computed(function () {
                            var value = ko.utils.unwrapObservable(valueAccessor()),
                                componentName, componentParams;

                            if (typeof value === 'string') {
                                componentName = value;
                            } else {
                                componentName = ko.utils.unwrapObservable(value['name']);
                                componentParams = ko.utils.unwrapObservable(value['params']);
                            }

                            if (!componentName) {
                                throw new Error('No component name specified');
                            }

                            var asyncContext = ko.bindingEvent.startPossiblyAsyncContentBinding(element, bindingContext);

                            var loadingOperationId = currentLoadingOperationId = ++componentLoadingOperationUniqueId;
                            ko.components.get(componentName, function (componentDefinition) {
                                // If this is not the current load operation for this element, ignore it.
                                if (currentLoadingOperationId !== loadingOperationId) {
                                    return;
                                }

                                // Clean up previous state
                                disposeAssociatedComponentViewModel();

                                // Instantiate and bind new component. Implicitly this cleans any old DOM nodes.
                                if (!componentDefinition) {
                                    throw new Error('Unknown component \'' + componentName + '\'');
                                }
                                cloneTemplateIntoElement(componentName, componentDefinition, element);

                                var componentInfo = {
                                    'element': element,
                                    'templateNodes': originalChildNodes
                                };

                                var componentViewModel = createViewModel(componentDefinition, componentParams, componentInfo),
                                    childBindingContext = asyncContext['createChildContext'](componentViewModel, {
                                        'extend': function (ctx) {
                                            ctx['$component'] = componentViewModel;
                                            ctx['$componentTemplateNodes'] = originalChildNodes;
                                        }
                                    });

                                if (componentViewModel && componentViewModel['koDescendantsComplete']) {
                                    afterRenderSub = ko.bindingEvent.subscribe(element, ko.bindingEvent.descendantsComplete, componentViewModel['koDescendantsComplete'], componentViewModel);
                                }

                                currentViewModel = componentViewModel;
                                ko.applyBindingsToDescendants(childBindingContext, element);
                            });
                        }, null, { disposeWhenNodeIsRemoved: element });

                        return { 'controlsDescendantBindings': true };
                    }
                };

                ko.virtualElements.allowedBindings['component'] = true;

                function cloneTemplateIntoElement(componentName, componentDefinition, element) {
                    var template = componentDefinition['template'];
                    if (!template) {
                        throw new Error('Component \'' + componentName + '\' has no template');
                    }

                    var clonedNodesArray = ko.utils.cloneNodes(template);
                    ko.virtualElements.setDomNodeChildren(element, clonedNodesArray);
                }

                function createViewModel(componentDefinition, componentParams, componentInfo) {
                    var componentViewModelFactory = componentDefinition['createViewModel'];
                    return componentViewModelFactory
                        ? componentViewModelFactory.call(componentDefinition, componentParams, componentInfo)
                        : componentParams; // Template-only component
                }

            })();
            var attrHtmlToJavaScriptMap = { 'class': 'className', 'for': 'htmlFor' };
            ko.bindingHandlers['attr'] = {
                'update': function (element, valueAccessor, allBindings) {
                    var value = ko.utils.unwrapObservable(valueAccessor()) || {};
                    ko.utils.objectForEach(value, function (attrName, attrValue) {
                        attrValue = ko.utils.unwrapObservable(attrValue);

                        // Find the namespace of this attribute, if any.
                        var prefixLen = attrName.indexOf(':');
                        var namespace = "lookupNamespaceURI" in element && prefixLen > 0 && element.lookupNamespaceURI(attrName.substr(0, prefixLen));

                        // To cover cases like "attr: { checked:someProp }", we want to remove the attribute entirely
                        // when someProp is a "no value"-like value (strictly null, false, or undefined)
                        // (because the absence of the "checked" attr is how to mark an element as not checked, etc.)
                        var toRemove = (attrValue === false) || (attrValue === null) || (attrValue === undefined);
                        if (toRemove) {
                            namespace ? element.removeAttributeNS(namespace, attrName) : element.removeAttribute(attrName);
                        } else {
                            attrValue = attrValue.toString();
                        }

                        // In IE <= 7 and IE8 Quirks Mode, you have to use the JavaScript property name instead of the
                        // HTML attribute name for certain attributes. IE8 Standards Mode supports the correct behavior,
                        // but instead of figuring out the mode, we'll just set the attribute through the JavaScript
                        // property for IE <= 8.
                        if (ko.utils.ieVersion <= 8 && attrName in attrHtmlToJavaScriptMap) {
                            attrName = attrHtmlToJavaScriptMap[attrName];
                            if (toRemove)
                                element.removeAttribute(attrName);
                            else
                                element[attrName] = attrValue;
                        } else if (!toRemove) {
                            namespace ? element.setAttributeNS(namespace, attrName, attrValue) : element.setAttribute(attrName, attrValue);
                        }

                        // Treat "name" specially - although you can think of it as an attribute, it also needs
                        // special handling on older versions of IE (https://github.com/SteveSanderson/knockout/pull/333)
                        // Deliberately being case-sensitive here because XHTML would regard "Name" as a different thing
                        // entirely, and there's no strong reason to allow for such casing in HTML.
                        if (attrName === "name") {
                            ko.utils.setElementName(element, toRemove ? "" : attrValue);
                        }
                    });
                }
            };
            (function () {

                ko.bindingHandlers['checked'] = {
                    'after': ['value', 'attr'],
                    'init': function (element, valueAccessor, allBindings) {
                        var checkedValue = ko.pureComputed(function () {
                            // Treat "value" like "checkedValue" when it is included with "checked" binding
                            if (allBindings['has']('checkedValue')) {
                                return ko.utils.unwrapObservable(allBindings.get('checkedValue'));
                            } else if (useElementValue) {
                                if (allBindings['has']('value')) {
                                    return ko.utils.unwrapObservable(allBindings.get('value'));
                                } else {
                                    return element.value;
                                }
                            }
                        });

                        function updateModel() {
                            // This updates the model value from the view value.
                            // It runs in response to DOM events (click) and changes in checkedValue.
                            var isChecked = element.checked,
                                elemValue = checkedValue();

                            // When we're first setting up this computed, don't change any model state.
                            if (ko.computedContext.isInitial()) {
                                return;
                            }

                            // We can ignore unchecked radio buttons, because some other radio
                            // button will be checked, and that one can take care of updating state.
                            // Also ignore value changes to an already unchecked checkbox.
                            if (!isChecked && (isRadio || ko.computedContext.getDependenciesCount())) {
                                return;
                            }

                            var modelValue = ko.dependencyDetection.ignore(valueAccessor);
                            if (valueIsArray) {
                                var writableValue = rawValueIsNonArrayObservable ? modelValue.peek() : modelValue,
                                    saveOldValue = oldElemValue;
                                oldElemValue = elemValue;

                                if (saveOldValue !== elemValue) {
                                    // When we're responding to the checkedValue changing, and the element is
                                    // currently checked, replace the old elem value with the new elem value
                                    // in the model array.
                                    if (isChecked) {
                                        ko.utils.addOrRemoveItem(writableValue, elemValue, true);
                                        ko.utils.addOrRemoveItem(writableValue, saveOldValue, false);
                                    }
                                } else {
                                    // When we're responding to the user having checked/unchecked a checkbox,
                                    // add/remove the element value to the model array.
                                    ko.utils.addOrRemoveItem(writableValue, elemValue, isChecked);
                                }

                                if (rawValueIsNonArrayObservable && ko.isWriteableObservable(modelValue)) {
                                    modelValue(writableValue);
                                }
                            } else {
                                if (isCheckbox) {
                                    if (elemValue === undefined) {
                                        elemValue = isChecked;
                                    } else if (!isChecked) {
                                        elemValue = undefined;
                                    }
                                }
                                ko.expressionRewriting.writeValueToProperty(modelValue, allBindings, 'checked', elemValue, true);
                            }
                        };

                        function updateView() {
                            // This updates the view value from the model value.
                            // It runs in response to changes in the bound (checked) value.
                            var modelValue = ko.utils.unwrapObservable(valueAccessor()),
                                elemValue = checkedValue();

                            if (valueIsArray) {
                                // When a checkbox is bound to an array, being checked represents its value being present in that array
                                element.checked = ko.utils.arrayIndexOf(modelValue, elemValue) >= 0;
                                oldElemValue = elemValue;
                            } else if (isCheckbox && elemValue === undefined) {
                                // When a checkbox is bound to any other value (not an array) and "checkedValue" is not defined,
                                // being checked represents the value being trueish
                                element.checked = !!modelValue;
                            } else {
                                // Otherwise, being checked means that the checkbox or radio button's value corresponds to the model value
                                element.checked = (checkedValue() === modelValue);
                            }
                        };

                        var isCheckbox = element.type == "checkbox",
                            isRadio = element.type == "radio";

                        // Only bind to check boxes and radio buttons
                        if (!isCheckbox && !isRadio) {
                            return;
                        }

                        var rawValue = valueAccessor(),
                            valueIsArray = isCheckbox && (ko.utils.unwrapObservable(rawValue) instanceof Array),
                            rawValueIsNonArrayObservable = !(valueIsArray && rawValue.push && rawValue.splice),
                            useElementValue = isRadio || valueIsArray,
                            oldElemValue = valueIsArray ? checkedValue() : undefined;

                        // IE 6 won't allow radio buttons to be selected unless they have a name
                        if (isRadio && !element.name)
                            ko.bindingHandlers['uniqueName']['init'](element, function () { return true });

                        // Set up two computeds to update the binding:

                        // The first responds to changes in the checkedValue value and to element clicks
                        ko.computed(updateModel, null, { disposeWhenNodeIsRemoved: element });
                        ko.utils.registerEventHandler(element, "click", updateModel);

                        // The second responds to changes in the model value (the one associated with the checked binding)
                        ko.computed(updateView, null, { disposeWhenNodeIsRemoved: element });

                        rawValue = undefined;
                    }
                };
                ko.expressionRewriting.twoWayBindings['checked'] = true;

                ko.bindingHandlers['checkedValue'] = {
                    'update': function (element, valueAccessor) {
                        element.value = ko.utils.unwrapObservable(valueAccessor());
                    }
                };

            })(); var classesWrittenByBindingKey = '__ko__cssValue';
            ko.bindingHandlers['class'] = {
                'update': function (element, valueAccessor) {
                    var value = ko.utils.stringTrim(ko.utils.unwrapObservable(valueAccessor()));
                    ko.utils.toggleDomNodeCssClass(element, element[classesWrittenByBindingKey], false);
                    element[classesWrittenByBindingKey] = value;
                    ko.utils.toggleDomNodeCssClass(element, value, true);
                }
            };

            ko.bindingHandlers['css'] = {
                'update': function (element, valueAccessor) {
                    var value = ko.utils.unwrapObservable(valueAccessor());
                    if (value !== null && typeof value == "object") {
                        ko.utils.objectForEach(value, function (className, shouldHaveClass) {
                            shouldHaveClass = ko.utils.unwrapObservable(shouldHaveClass);
                            ko.utils.toggleDomNodeCssClass(element, className, shouldHaveClass);
                        });
                    } else {
                        ko.bindingHandlers['class']['update'](element, valueAccessor);
                    }
                }
            };
            ko.bindingHandlers['enable'] = {
                'update': function (element, valueAccessor) {
                    var value = ko.utils.unwrapObservable(valueAccessor());
                    if (value && element.disabled)
                        element.removeAttribute("disabled");
                    else if ((!value) && (!element.disabled))
                        element.disabled = true;
                }
            };

            ko.bindingHandlers['disable'] = {
                'update': function (element, valueAccessor) {
                    ko.bindingHandlers['enable']['update'](element, function () { return !ko.utils.unwrapObservable(valueAccessor()) });
                }
            };
            // For certain common events (currently just 'click'), allow a simplified data-binding syntax
            // e.g. click:handler instead of the usual full-length event:{click:handler}
            function makeEventHandlerShortcut(eventName) {
                ko.bindingHandlers[eventName] = {
                    'init': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                        var newValueAccessor = function () {
                            var result = {};
                            result[eventName] = valueAccessor();
                            return result;
                        };
                        return ko.bindingHandlers['event']['init'].call(this, element, newValueAccessor, allBindings, viewModel, bindingContext);
                    }
                }
            }

            ko.bindingHandlers['event'] = {
                'init': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                    var eventsToHandle = valueAccessor() || {};
                    ko.utils.objectForEach(eventsToHandle, function (eventName) {
                        if (typeof eventName == "string") {
                            ko.utils.registerEventHandler(element, eventName, function (event) {
                                var handlerReturnValue;
                                var handlerFunction = valueAccessor()[eventName];
                                if (!handlerFunction)
                                    return;

                                try {
                                    // Take all the event args, and prefix with the viewmodel
                                    var argsForHandler = ko.utils.makeArray(arguments);
                                    viewModel = bindingContext['$data'];
                                    argsForHandler.unshift(viewModel);
                                    handlerReturnValue = handlerFunction.apply(viewModel, argsForHandler);
                                } finally {
                                    if (handlerReturnValue !== true) { // Normally we want to prevent default action. Developer can override this be explicitly returning true.
                                        if (event.preventDefault)
                                            event.preventDefault();
                                        else
                                            event.returnValue = false;
                                    }
                                }

                                var bubble = allBindings.get(eventName + 'Bubble') !== false;
                                if (!bubble) {
                                    event.cancelBubble = true;
                                    if (event.stopPropagation)
                                        event.stopPropagation();
                                }
                            });
                        }
                    });
                }
            };
            // "foreach: someExpression" is equivalent to "template: { foreach: someExpression }"
            // "foreach: { data: someExpression, afterAdd: myfn }" is equivalent to "template: { foreach: someExpression, afterAdd: myfn }"
            ko.bindingHandlers['foreach'] = {
                makeTemplateValueAccessor: function (valueAccessor) {
                    return function () {
                        var modelValue = valueAccessor(),
                            unwrappedValue = ko.utils.peekObservable(modelValue);    // Unwrap without setting a dependency here

                        // If unwrappedValue is the array, pass in the wrapped value on its own
                        // The value will be unwrapped and tracked within the template binding
                        // (See https://github.com/SteveSanderson/knockout/issues/523)
                        if ((!unwrappedValue) || typeof unwrappedValue.length == "number")
                            return { 'foreach': modelValue, 'templateEngine': ko.nativeTemplateEngine.instance };

                        // If unwrappedValue.data is the array, preserve all relevant options and unwrap again value so we get updates
                        ko.utils.unwrapObservable(modelValue);
                        return {
                            'foreach': unwrappedValue['data'],
                            'as': unwrappedValue['as'],
                            'noChildContext': unwrappedValue['noChildContext'],
                            'includeDestroyed': unwrappedValue['includeDestroyed'],
                            'afterAdd': unwrappedValue['afterAdd'],
                            'beforeRemove': unwrappedValue['beforeRemove'],
                            'afterRender': unwrappedValue['afterRender'],
                            'beforeMove': unwrappedValue['beforeMove'],
                            'afterMove': unwrappedValue['afterMove'],
                            'templateEngine': ko.nativeTemplateEngine.instance
                        };
                    };
                },
                'init': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                    return ko.bindingHandlers['template']['init'](element, ko.bindingHandlers['foreach'].makeTemplateValueAccessor(valueAccessor));
                },
                'update': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                    return ko.bindingHandlers['template']['update'](element, ko.bindingHandlers['foreach'].makeTemplateValueAccessor(valueAccessor), allBindings, viewModel, bindingContext);
                }
            };
            ko.expressionRewriting.bindingRewriteValidators['foreach'] = false; // Can't rewrite control flow bindings
            ko.virtualElements.allowedBindings['foreach'] = true;
            var hasfocusUpdatingProperty = '__ko_hasfocusUpdating';
            var hasfocusLastValue = '__ko_hasfocusLastValue';
            ko.bindingHandlers['hasfocus'] = {
                'init': function (element, valueAccessor, allBindings) {
                    var handleElementFocusChange = function (isFocused) {
                        // Where possible, ignore which event was raised and determine focus state using activeElement,
                        // as this avoids phantom focus/blur events raised when changing tabs in modern browsers.
                        // However, not all KO-targeted browsers (Firefox 2) support activeElement. For those browsers,
                        // prevent a loss of focus when changing tabs/windows by setting a flag that prevents hasfocus
                        // from calling 'blur()' on the element when it loses focus.
                        // Discussion at https://github.com/SteveSanderson/knockout/pull/352
                        element[hasfocusUpdatingProperty] = true;
                        var ownerDoc = element.ownerDocument;
                        if ("activeElement" in ownerDoc) {
                            var active;
                            try {
                                active = ownerDoc.activeElement;
                            } catch (e) {
                                // IE9 throws if you access activeElement during page load (see issue #703)
                                active = ownerDoc.body;
                            }
                            isFocused = (active === element);
                        }
                        var modelValue = valueAccessor();
                        ko.expressionRewriting.writeValueToProperty(modelValue, allBindings, 'hasfocus', isFocused, true);

                        //cache the latest value, so we can avoid unnecessarily calling focus/blur in the update function
                        element[hasfocusLastValue] = isFocused;
                        element[hasfocusUpdatingProperty] = false;
                    };
                    var handleElementFocusIn = handleElementFocusChange.bind(null, true);
                    var handleElementFocusOut = handleElementFocusChange.bind(null, false);

                    ko.utils.registerEventHandler(element, "focus", handleElementFocusIn);
                    ko.utils.registerEventHandler(element, "focusin", handleElementFocusIn); // For IE
                    ko.utils.registerEventHandler(element, "blur", handleElementFocusOut);
                    ko.utils.registerEventHandler(element, "focusout", handleElementFocusOut); // For IE

                    // Assume element is not focused (prevents "blur" being called initially)
                    element[hasfocusLastValue] = false;
                },
                'update': function (element, valueAccessor) {
                    var value = !!ko.utils.unwrapObservable(valueAccessor());

                    if (!element[hasfocusUpdatingProperty] && element[hasfocusLastValue] !== value) {
                        value ? element.focus() : element.blur();

                        // In IE, the blur method doesn't always cause the element to lose focus (for example, if the window is not in focus).
                        // Setting focus to the body element does seem to be reliable in IE, but should only be used if we know that the current
                        // element was focused already.
                        if (!value && element[hasfocusLastValue]) {
                            element.ownerDocument.body.focus();
                        }

                        // For IE, which doesn't reliably fire "focus" or "blur" events synchronously
                        ko.dependencyDetection.ignore(ko.utils.triggerEvent, null, [element, value ? "focusin" : "focusout"]);
                    }
                }
            };
            ko.expressionRewriting.twoWayBindings['hasfocus'] = true;

            ko.bindingHandlers['hasFocus'] = ko.bindingHandlers['hasfocus']; // Make "hasFocus" an alias
            ko.expressionRewriting.twoWayBindings['hasFocus'] = 'hasfocus';
            ko.bindingHandlers['html'] = {
                'init': function () {
                    // Prevent binding on the dynamically-injected HTML (as developers are unlikely to expect that, and it has security implications)
                    return { 'controlsDescendantBindings': true };
                },
                'update': function (element, valueAccessor) {
                    // setHtml will unwrap the value if needed
                    ko.utils.setHtml(element, valueAccessor());
                }
            };
            (function () {

                // Makes a binding like with or if
                function makeWithIfBinding(bindingKey, isWith, isNot) {
                    ko.bindingHandlers[bindingKey] = {
                        'init': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                            var didDisplayOnLastUpdate, savedNodes, contextOptions = {}, completeOnRender, needAsyncContext, renderOnEveryChange;

                            if (isWith) {
                                var as = allBindings.get('as'), noChildContext = allBindings.get('noChildContext');
                                renderOnEveryChange = !(as && noChildContext);
                                contextOptions = { 'as': as, 'noChildContext': noChildContext, 'exportDependencies': renderOnEveryChange };
                            }

                            completeOnRender = allBindings.get("completeOn") == "render";
                            needAsyncContext = completeOnRender || allBindings['has'](ko.bindingEvent.descendantsComplete);

                            ko.computed(function () {
                                var value = ko.utils.unwrapObservable(valueAccessor()),
                                    shouldDisplay = !isNot !== !value, // equivalent to isNot ? !value : !!value,
                                    isInitial = !savedNodes,
                                    childContext;

                                if (!renderOnEveryChange && shouldDisplay === didDisplayOnLastUpdate) {
                                    return;
                                }

                                if (needAsyncContext) {
                                    bindingContext = ko.bindingEvent.startPossiblyAsyncContentBinding(element, bindingContext);
                                }

                                if (shouldDisplay) {
                                    if (!isWith || renderOnEveryChange) {
                                        contextOptions['dataDependency'] = ko.computedContext.computed();
                                    }

                                    if (isWith) {
                                        childContext = bindingContext['createChildContext'](typeof value == "function" ? value : valueAccessor, contextOptions);
                                    } else if (ko.computedContext.getDependenciesCount()) {
                                        childContext = bindingContext['extend'](null, contextOptions);
                                    } else {
                                        childContext = bindingContext;
                                    }
                                }

                                // Save a copy of the inner nodes on the initial update, but only if we have dependencies.
                                if (isInitial && ko.computedContext.getDependenciesCount()) {
                                    savedNodes = ko.utils.cloneNodes(ko.virtualElements.childNodes(element), true /* shouldCleanNodes */);
                                }

                                if (shouldDisplay) {
                                    if (!isInitial) {
                                        ko.virtualElements.setDomNodeChildren(element, ko.utils.cloneNodes(savedNodes));
                                    }

                                    ko.applyBindingsToDescendants(childContext, element);
                                } else {
                                    ko.virtualElements.emptyNode(element);

                                    if (!completeOnRender) {
                                        ko.bindingEvent.notify(element, ko.bindingEvent.childrenComplete);
                                    }
                                }

                                didDisplayOnLastUpdate = shouldDisplay;

                            }, null, { disposeWhenNodeIsRemoved: element });

                            return { 'controlsDescendantBindings': true };
                        }
                    };
                    ko.expressionRewriting.bindingRewriteValidators[bindingKey] = false; // Can't rewrite control flow bindings
                    ko.virtualElements.allowedBindings[bindingKey] = true;
                }

                // Construct the actual binding handlers
                makeWithIfBinding('if');
                makeWithIfBinding('ifnot', false /* isWith */, true /* isNot */);
                makeWithIfBinding('with', true /* isWith */);

            })(); ko.bindingHandlers['let'] = {
                'init': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                    // Make a modified binding context, with extra properties, and apply it to descendant elements
                    var innerContext = bindingContext['extend'](valueAccessor);
                    ko.applyBindingsToDescendants(innerContext, element);

                    return { 'controlsDescendantBindings': true };
                }
            };
            ko.virtualElements.allowedBindings['let'] = true;
            var captionPlaceholder = {};
            ko.bindingHandlers['options'] = {
                'init': function (element) {
                    if (ko.utils.tagNameLower(element) !== "select")
                        throw new Error("options binding applies only to SELECT elements");

                    // Remove all existing <option>s.
                    while (element.length > 0) {
                        element.remove(0);
                    }

                    // Ensures that the binding processor doesn't try to bind the options
                    return { 'controlsDescendantBindings': true };
                },
                'update': function (element, valueAccessor, allBindings) {
                    function selectedOptions() {
                        return ko.utils.arrayFilter(element.options, function (node) { return node.selected; });
                    }

                    var selectWasPreviouslyEmpty = element.length == 0,
                        multiple = element.multiple,
                        previousScrollTop = (!selectWasPreviouslyEmpty && multiple) ? element.scrollTop : null,
                        unwrappedArray = ko.utils.unwrapObservable(valueAccessor()),
                        valueAllowUnset = allBindings.get('valueAllowUnset') && allBindings['has']('value'),
                        includeDestroyed = allBindings.get('optionsIncludeDestroyed'),
                        arrayToDomNodeChildrenOptions = {},
                        captionValue,
                        filteredArray,
                        previousSelectedValues = [];

                    if (!valueAllowUnset) {
                        if (multiple) {
                            previousSelectedValues = ko.utils.arrayMap(selectedOptions(), ko.selectExtensions.readValue);
                        } else if (element.selectedIndex >= 0) {
                            previousSelectedValues.push(ko.selectExtensions.readValue(element.options[element.selectedIndex]));
                        }
                    }

                    if (unwrappedArray) {
                        if (typeof unwrappedArray.length == "undefined") // Coerce single value into array
                            unwrappedArray = [unwrappedArray];

                        // Filter out any entries marked as destroyed
                        filteredArray = ko.utils.arrayFilter(unwrappedArray, function (item) {
                            return includeDestroyed || item === undefined || item === null || !ko.utils.unwrapObservable(item['_destroy']);
                        });

                        // If caption is included, add it to the array
                        if (allBindings['has']('optionsCaption')) {
                            captionValue = ko.utils.unwrapObservable(allBindings.get('optionsCaption'));
                            // If caption value is null or undefined, don't show a caption
                            if (captionValue !== null && captionValue !== undefined) {
                                filteredArray.unshift(captionPlaceholder);
                            }
                        }
                    } else {
                        // If a falsy value is provided (e.g. null), we'll simply empty the select element
                    }

                    function applyToObject(object, predicate, defaultValue) {
                        var predicateType = typeof predicate;
                        if (predicateType == "function")    // Given a function; run it against the data value
                            return predicate(object);
                        else if (predicateType == "string") // Given a string; treat it as a property name on the data value
                            return object[predicate];
                        else                                // Given no optionsText arg; use the data value itself
                            return defaultValue;
                    }

                    // The following functions can run at two different times:
                    // The first is when the whole array is being updated directly from this binding handler.
                    // The second is when an observable value for a specific array entry is updated.
                    // oldOptions will be empty in the first case, but will be filled with the previously generated option in the second.
                    var itemUpdate = false;
                    function optionForArrayItem(arrayEntry, index, oldOptions) {
                        if (oldOptions.length) {
                            previousSelectedValues = !valueAllowUnset && oldOptions[0].selected ? [ko.selectExtensions.readValue(oldOptions[0])] : [];
                            itemUpdate = true;
                        }
                        var option = element.ownerDocument.createElement("option");
                        if (arrayEntry === captionPlaceholder) {
                            ko.utils.setTextContent(option, allBindings.get('optionsCaption'));
                            ko.selectExtensions.writeValue(option, undefined);
                        } else {
                            // Apply a value to the option element
                            var optionValue = applyToObject(arrayEntry, allBindings.get('optionsValue'), arrayEntry);
                            ko.selectExtensions.writeValue(option, ko.utils.unwrapObservable(optionValue));

                            // Apply some text to the option element
                            var optionText = applyToObject(arrayEntry, allBindings.get('optionsText'), optionValue);
                            ko.utils.setTextContent(option, optionText);
                        }
                        return [option];
                    }

                    // By using a beforeRemove callback, we delay the removal until after new items are added. This fixes a selection
                    // problem in IE<=8 and Firefox. See https://github.com/knockout/knockout/issues/1208
                    arrayToDomNodeChildrenOptions['beforeRemove'] =
                        function (option) {
                            element.removeChild(option);
                        };

                    function setSelectionCallback(arrayEntry, newOptions) {
                        if (itemUpdate && valueAllowUnset) {
                            // The model value is authoritative, so make sure its value is the one selected
                            ko.bindingEvent.notify(element, ko.bindingEvent.childrenComplete);
                        } else if (previousSelectedValues.length) {
                            // IE6 doesn't like us to assign selection to OPTION nodes before they're added to the document.
                            // That's why we first added them without selection. Now it's time to set the selection.
                            var isSelected = ko.utils.arrayIndexOf(previousSelectedValues, ko.selectExtensions.readValue(newOptions[0])) >= 0;
                            ko.utils.setOptionNodeSelectionState(newOptions[0], isSelected);

                            // If this option was changed from being selected during a single-item update, notify the change
                            if (itemUpdate && !isSelected) {
                                ko.dependencyDetection.ignore(ko.utils.triggerEvent, null, [element, "change"]);
                            }
                        }
                    }

                    var callback = setSelectionCallback;
                    if (allBindings['has']('optionsAfterRender') && typeof allBindings.get('optionsAfterRender') == "function") {
                        callback = function (arrayEntry, newOptions) {
                            setSelectionCallback(arrayEntry, newOptions);
                            ko.dependencyDetection.ignore(allBindings.get('optionsAfterRender'), null, [newOptions[0], arrayEntry !== captionPlaceholder ? arrayEntry : undefined]);
                        }
                    }

                    ko.utils.setDomNodeChildrenFromArrayMapping(element, filteredArray, optionForArrayItem, arrayToDomNodeChildrenOptions, callback);

                    if (!valueAllowUnset) {
                        // Determine if the selection has changed as a result of updating the options list
                        var selectionChanged;
                        if (multiple) {
                            // For a multiple-select box, compare the new selection count to the previous one
                            // But if nothing was selected before, the selection can't have changed
                            selectionChanged = previousSelectedValues.length && selectedOptions().length < previousSelectedValues.length;
                        } else {
                            // For a single-select box, compare the current value to the previous value
                            // But if nothing was selected before or nothing is selected now, just look for a change in selection
                            selectionChanged = (previousSelectedValues.length && element.selectedIndex >= 0)
                                ? (ko.selectExtensions.readValue(element.options[element.selectedIndex]) !== previousSelectedValues[0])
                                : (previousSelectedValues.length || element.selectedIndex >= 0);
                        }

                        // Ensure consistency between model value and selected option.
                        // If the dropdown was changed so that selection is no longer the same,
                        // notify the value or selectedOptions binding.
                        if (selectionChanged) {
                            ko.dependencyDetection.ignore(ko.utils.triggerEvent, null, [element, "change"]);
                        }
                    }

                    if (valueAllowUnset || ko.computedContext.isInitial()) {
                        ko.bindingEvent.notify(element, ko.bindingEvent.childrenComplete);
                    }

                    // Workaround for IE bug
                    ko.utils.ensureSelectElementIsRenderedCorrectly(element);

                    if (previousScrollTop && Math.abs(previousScrollTop - element.scrollTop) > 20)
                        element.scrollTop = previousScrollTop;
                }
            };
            ko.bindingHandlers['options'].optionValueDomDataKey = ko.utils.domData.nextKey();
            ko.bindingHandlers['selectedOptions'] = {
                'init': function (element, valueAccessor, allBindings) {
                    function updateFromView() {
                        var value = valueAccessor(), valueToWrite = [];
                        ko.utils.arrayForEach(element.getElementsByTagName("option"), function (node) {
                            if (node.selected)
                                valueToWrite.push(ko.selectExtensions.readValue(node));
                        });
                        ko.expressionRewriting.writeValueToProperty(value, allBindings, 'selectedOptions', valueToWrite);
                    }

                    function updateFromModel() {
                        var newValue = ko.utils.unwrapObservable(valueAccessor()),
                            previousScrollTop = element.scrollTop;

                        if (newValue && typeof newValue.length == "number") {
                            ko.utils.arrayForEach(element.getElementsByTagName("option"), function (node) {
                                var isSelected = ko.utils.arrayIndexOf(newValue, ko.selectExtensions.readValue(node)) >= 0;
                                if (node.selected != isSelected) {      // This check prevents flashing of the select element in IE
                                    ko.utils.setOptionNodeSelectionState(node, isSelected);
                                }
                            });
                        }

                        element.scrollTop = previousScrollTop;
                    }

                    if (ko.utils.tagNameLower(element) != "select") {
                        throw new Error("selectedOptions binding applies only to SELECT elements");
                    }

                    var updateFromModelComputed;
                    ko.bindingEvent.subscribe(element, ko.bindingEvent.childrenComplete, function () {
                        if (!updateFromModelComputed) {
                            ko.utils.registerEventHandler(element, "change", updateFromView);
                            updateFromModelComputed = ko.computed(updateFromModel, null, { disposeWhenNodeIsRemoved: element });
                        } else {
                            updateFromView();
                        }
                    }, null, { 'notifyImmediately': true });
                },
                'update': function () { } // Keep for backwards compatibility with code that may have wrapped binding
            };
            ko.expressionRewriting.twoWayBindings['selectedOptions'] = true;
            ko.bindingHandlers['style'] = {
                'update': function (element, valueAccessor) {
                    var value = ko.utils.unwrapObservable(valueAccessor() || {});
                    ko.utils.objectForEach(value, function (styleName, styleValue) {
                        styleValue = ko.utils.unwrapObservable(styleValue);

                        if (styleValue === null || styleValue === undefined || styleValue === false) {
                            // Empty string removes the value, whereas null/undefined have no effect
                            styleValue = "";
                        }

                        if (jQueryInstance) {
                            jQueryInstance(element)['css'](styleName, styleValue);
                        } else if (/^--/.test(styleName)) {
                            // Is styleName a custom CSS property?
                            element.style.setProperty(styleName, styleValue);
                        } else {
                            styleName = styleName.replace(/-(\w)/g, function (all, letter) {
                                return letter.toUpperCase();
                            });

                            var previousStyle = element.style[styleName];
                            element.style[styleName] = styleValue;

                            if (styleValue !== previousStyle && element.style[styleName] == previousStyle && !isNaN(styleValue)) {
                                element.style[styleName] = styleValue + "px";
                            }
                        }
                    });
                }
            };
            ko.bindingHandlers['submit'] = {
                'init': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                    if (typeof valueAccessor() != "function")
                        throw new Error("The value for a submit binding must be a function");
                    ko.utils.registerEventHandler(element, "submit", function (event) {
                        var handlerReturnValue;
                        var value = valueAccessor();
                        try { handlerReturnValue = value.call(bindingContext['$data'], element); }
                        finally {
                            if (handlerReturnValue !== true) { // Normally we want to prevent default action. Developer can override this be explicitly returning true.
                                if (event.preventDefault)
                                    event.preventDefault();
                                else
                                    event.returnValue = false;
                            }
                        }
                    });
                }
            };
            ko.bindingHandlers['text'] = {
                'init': function () {
                    // Prevent binding on the dynamically-injected text node (as developers are unlikely to expect that, and it has security implications).
                    // It should also make things faster, as we no longer have to consider whether the text node might be bindable.
                    return { 'controlsDescendantBindings': true };
                },
                'update': function (element, valueAccessor) {
                    ko.utils.setTextContent(element, valueAccessor());
                }
            };
            ko.virtualElements.allowedBindings['text'] = true;
            (function () {

                if (window && window.navigator) {
                    var parseVersion = function (matches) {
                        if (matches) {
                            return parseFloat(matches[1]);
                        }
                    };

                    // Detect various browser versions because some old versions don't fully support the 'input' event
                    var userAgent = window.navigator.userAgent,
                        operaVersion, chromeVersion, safariVersion, firefoxVersion, ieVersion, edgeVersion;

                    (operaVersion = window.opera && window.opera.version && parseInt(window.opera.version()))
                        || (edgeVersion = parseVersion(userAgent.match(/Edge\/([^ ]+)$/)))
                        || (chromeVersion = parseVersion(userAgent.match(/Chrome\/([^ ]+)/)))
                        || (safariVersion = parseVersion(userAgent.match(/Version\/([^ ]+) Safari/)))
                        || (firefoxVersion = parseVersion(userAgent.match(/Firefox\/([^ ]+)/)))
                        || (ieVersion = ko.utils.ieVersion || parseVersion(userAgent.match(/MSIE ([^ ]+)/)))      // Detects up to IE 10
                        || (ieVersion = parseVersion(userAgent.match(/rv:([^ )]+)/)));      // Detects IE 11
                }

                // IE 8 and 9 have bugs that prevent the normal events from firing when the value changes.
                // But it does fire the 'selectionchange' event on many of those, presumably because the
                // cursor is moving and that counts as the selection changing. The 'selectionchange' event is
                // fired at the document level only and doesn't directly indicate which element changed. We
                // set up just one event handler for the document and use 'activeElement' to determine which
                // element was changed.
                if (ieVersion >= 8 && ieVersion < 10) {
                    var selectionChangeRegisteredName = ko.utils.domData.nextKey(),
                        selectionChangeHandlerName = ko.utils.domData.nextKey();
                    var selectionChangeHandler = function (event) {
                        var target = this.activeElement,
                            handler = target && ko.utils.domData.get(target, selectionChangeHandlerName);
                        if (handler) {
                            handler(event);
                        }
                    };
                    var registerForSelectionChangeEvent = function (element, handler) {
                        var ownerDoc = element.ownerDocument;
                        if (!ko.utils.domData.get(ownerDoc, selectionChangeRegisteredName)) {
                            ko.utils.domData.set(ownerDoc, selectionChangeRegisteredName, true);
                            ko.utils.registerEventHandler(ownerDoc, 'selectionchange', selectionChangeHandler);
                        }
                        ko.utils.domData.set(element, selectionChangeHandlerName, handler);
                    };
                }

                ko.bindingHandlers['textInput'] = {
                    'init': function (element, valueAccessor, allBindings) {

                        var previousElementValue = element.value,
                            timeoutHandle,
                            elementValueBeforeEvent;

                        var updateModel = function (event) {
                            clearTimeout(timeoutHandle);
                            elementValueBeforeEvent = timeoutHandle = undefined;

                            var elementValue = element.value;
                            if (previousElementValue !== elementValue) {
                                // Provide a way for tests to know exactly which event was processed
                                if (DEBUG && event) element['_ko_textInputProcessedEvent'] = event.type;
                                previousElementValue = elementValue;
                                ko.expressionRewriting.writeValueToProperty(valueAccessor(), allBindings, 'textInput', elementValue);
                            }
                        };

                        var deferUpdateModel = function (event) {
                            if (!timeoutHandle) {
                                // The elementValueBeforeEvent variable is set *only* during the brief gap between an
                                // event firing and the updateModel function running. This allows us to ignore model
                                // updates that are from the previous state of the element, usually due to techniques
                                // such as rateLimit. Such updates, if not ignored, can cause keystrokes to be lost.
                                elementValueBeforeEvent = element.value;
                                var handler = DEBUG ? updateModel.bind(element, { type: event.type }) : updateModel;
                                timeoutHandle = ko.utils.setTimeout(handler, 4);
                            }
                        };

                        // IE9 will mess up the DOM if you handle events synchronously which results in DOM changes (such as other bindings);
                        // so we'll make sure all updates are asynchronous
                        var ieUpdateModel = ko.utils.ieVersion == 9 ? deferUpdateModel : updateModel,
                            ourUpdate = false;

                        var updateView = function () {
                            var modelValue = ko.utils.unwrapObservable(valueAccessor());

                            if (modelValue === null || modelValue === undefined) {
                                modelValue = '';
                            }

                            if (elementValueBeforeEvent !== undefined && modelValue === elementValueBeforeEvent) {
                                ko.utils.setTimeout(updateView, 4);
                                return;
                            }

                            // Update the element only if the element and model are different. On some browsers, updating the value
                            // will move the cursor to the end of the input, which would be bad while the user is typing.
                            if (element.value !== modelValue) {
                                ourUpdate = true;  // Make sure we ignore events (propertychange) that result from updating the value
                                element.value = modelValue;
                                ourUpdate = false;
                                previousElementValue = element.value; // In case the browser changes the value (see #2281)
                            }
                        };

                        var onEvent = function (event, handler) {
                            ko.utils.registerEventHandler(element, event, handler);
                        };

                        if (DEBUG && ko.bindingHandlers['textInput']['_forceUpdateOn']) {
                            // Provide a way for tests to specify exactly which events are bound
                            ko.utils.arrayForEach(ko.bindingHandlers['textInput']['_forceUpdateOn'], function (eventName) {
                                if (eventName.slice(0, 5) == 'after') {
                                    onEvent(eventName.slice(5), deferUpdateModel);
                                } else {
                                    onEvent(eventName, updateModel);
                                }
                            });
                        } else {
                            if (ieVersion) {
                                // All versions (including 11) of Internet Explorer have a bug that they don't generate an input or propertychange event when ESC is pressed
                                onEvent('keypress', updateModel);
                            }
                            if (ieVersion < 11) {
                                // Internet Explorer <= 8 doesn't support the 'input' event, but does include 'propertychange' that fires whenever
                                // any property of an element changes. Unlike 'input', it also fires if a property is changed from JavaScript code,
                                // but that's an acceptable compromise for this binding. IE 9 and 10 support 'input', but since they don't always
                                // fire it when using autocomplete, we'll use 'propertychange' for them also.
                                onEvent('propertychange', function (event) {
                                    if (!ourUpdate && event.propertyName === 'value') {
                                        ieUpdateModel(event);
                                    }
                                });
                            }
                            if (ieVersion == 8) {
                                // IE 8 has a bug where it fails to fire 'propertychange' on the first update following a value change from
                                // JavaScript code. It also doesn't fire if you clear the entire value. To fix this, we bind to the following
                                // events too.
                                onEvent('keyup', updateModel);      // A single keystoke
                                onEvent('keydown', updateModel);    // The first character when a key is held down
                            }
                            if (registerForSelectionChangeEvent) {
                                // Internet Explorer 9 doesn't fire the 'input' event when deleting text, including using
                                // the backspace, delete, or ctrl-x keys, clicking the 'x' to clear the input, dragging text
                                // out of the field, and cutting or deleting text using the context menu. 'selectionchange'
                                // can detect all of those except dragging text out of the field, for which we use 'dragend'.
                                // These are also needed in IE8 because of the bug described above.
                                registerForSelectionChangeEvent(element, ieUpdateModel);  // 'selectionchange' covers cut, paste, drop, delete, etc.
                                onEvent('dragend', deferUpdateModel);
                            }

                            if (!ieVersion || ieVersion >= 9) {
                                // All other supported browsers support the 'input' event, which fires whenever the content of the element is changed
                                // through the user interface.
                                onEvent('input', ieUpdateModel);
                            }

                            if (safariVersion < 5 && ko.utils.tagNameLower(element) === "textarea") {
                                // Safari <5 doesn't fire the 'input' event for <textarea> elements (it does fire 'textInput'
                                // but only when typing). So we'll just catch as much as we can with keydown, cut, and paste.
                                onEvent('keydown', deferUpdateModel);
                                onEvent('paste', deferUpdateModel);
                                onEvent('cut', deferUpdateModel);
                            } else if (operaVersion < 11) {
                                // Opera 10 doesn't always fire the 'input' event for cut, paste, undo & drop operations.
                                // We can try to catch some of those using 'keydown'.
                                onEvent('keydown', deferUpdateModel);
                            } else if (firefoxVersion < 4.0) {
                                // Firefox <= 3.6 doesn't fire the 'input' event when text is filled in through autocomplete
                                onEvent('DOMAutoComplete', updateModel);

                                // Firefox <=3.5 doesn't fire the 'input' event when text is dropped into the input.
                                onEvent('dragdrop', updateModel);       // <3.5
                                onEvent('drop', updateModel);           // 3.5
                            } else if (edgeVersion && element.type === "number") {
                                // Microsoft Edge doesn't fire 'input' or 'change' events for number inputs when
                                // the value is changed via the up / down arrow keys
                                onEvent('keydown', deferUpdateModel);
                            }
                        }

                        // Bind to the change event so that we can catch programmatic updates of the value that fire this event.
                        onEvent('change', updateModel);

                        // To deal with browsers that don't notify any kind of event for some changes (IE, Safari, etc.)
                        onEvent('blur', updateModel);

                        ko.computed(updateView, null, { disposeWhenNodeIsRemoved: element });
                    }
                };
                ko.expressionRewriting.twoWayBindings['textInput'] = true;

                // textinput is an alias for textInput
                ko.bindingHandlers['textinput'] = {
                    // preprocess is the only way to set up a full alias
                    'preprocess': function (value, name, addBinding) {
                        addBinding('textInput', value);
                    }
                };

            })(); ko.bindingHandlers['uniqueName'] = {
                'init': function (element, valueAccessor) {
                    if (valueAccessor()) {
                        var name = "ko_unique_" + (++ko.bindingHandlers['uniqueName'].currentIndex);
                        ko.utils.setElementName(element, name);
                    }
                }
            };
            ko.bindingHandlers['uniqueName'].currentIndex = 0;
            ko.bindingHandlers['using'] = {
                'init': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                    var options;

                    if (allBindings['has']('as')) {
                        options = { 'as': allBindings.get('as'), 'noChildContext': allBindings.get('noChildContext') };
                    }

                    var innerContext = bindingContext['createChildContext'](valueAccessor, options);
                    ko.applyBindingsToDescendants(innerContext, element);

                    return { 'controlsDescendantBindings': true };
                }
            };
            ko.virtualElements.allowedBindings['using'] = true;
            ko.bindingHandlers['value'] = {
                'init': function (element, valueAccessor, allBindings) {
                    var tagName = ko.utils.tagNameLower(element),
                        isInputElement = tagName == "input";

                    // If the value binding is placed on a radio/checkbox, then just pass through to checkedValue and quit
                    if (isInputElement && (element.type == "checkbox" || element.type == "radio")) {
                        ko.applyBindingAccessorsToNode(element, { 'checkedValue': valueAccessor });
                        return;
                    }

                    var eventsToCatch = [];
                    var requestedEventsToCatch = allBindings.get("valueUpdate");
                    var propertyChangedFired = false;
                    var elementValueBeforeEvent = null;

                    if (requestedEventsToCatch) {
                        // Allow both individual event names, and arrays of event names
                        if (typeof requestedEventsToCatch == "string") {
                            eventsToCatch = [requestedEventsToCatch];
                        } else {
                            eventsToCatch = ko.utils.arrayGetDistinctValues(requestedEventsToCatch);
                        }
                        ko.utils.arrayRemoveItem(eventsToCatch, "change");  // We'll subscribe to "change" events later
                    }

                    var valueUpdateHandler = function () {
                        elementValueBeforeEvent = null;
                        propertyChangedFired = false;
                        var modelValue = valueAccessor();
                        var elementValue = ko.selectExtensions.readValue(element);
                        ko.expressionRewriting.writeValueToProperty(modelValue, allBindings, 'value', elementValue);
                    }

                    // Workaround for https://github.com/SteveSanderson/knockout/issues/122
                    // IE doesn't fire "change" events on textboxes if the user selects a value from its autocomplete list
                    var ieAutoCompleteHackNeeded = ko.utils.ieVersion && isInputElement && element.type == "text"
                        && element.autocomplete != "off" && (!element.form || element.form.autocomplete != "off");
                    if (ieAutoCompleteHackNeeded && ko.utils.arrayIndexOf(eventsToCatch, "propertychange") == -1) {
                        ko.utils.registerEventHandler(element, "propertychange", function () { propertyChangedFired = true });
                        ko.utils.registerEventHandler(element, "focus", function () { propertyChangedFired = false });
                        ko.utils.registerEventHandler(element, "blur", function () {
                            if (propertyChangedFired) {
                                valueUpdateHandler();
                            }
                        });
                    }

                    ko.utils.arrayForEach(eventsToCatch, function (eventName) {
                        // The syntax "after<eventname>" means "run the handler asynchronously after the event"
                        // This is useful, for example, to catch "keydown" events after the browser has updated the control
                        // (otherwise, ko.selectExtensions.readValue(this) will receive the control's value *before* the key event)
                        var handler = valueUpdateHandler;
                        if (ko.utils.stringStartsWith(eventName, "after")) {
                            handler = function () {
                                // The elementValueBeforeEvent variable is non-null *only* during the brief gap between
                                // a keyX event firing and the valueUpdateHandler running, which is scheduled to happen
                                // at the earliest asynchronous opportunity. We store this temporary information so that
                                // if, between keyX and valueUpdateHandler, the underlying model value changes separately,
                                // we can overwrite that model value change with the value the user just typed. Otherwise,
                                // techniques like rateLimit can trigger model changes at critical moments that will
                                // override the user's inputs, causing keystrokes to be lost.
                                elementValueBeforeEvent = ko.selectExtensions.readValue(element);
                                ko.utils.setTimeout(valueUpdateHandler, 0);
                            };
                            eventName = eventName.substring("after".length);
                        }
                        ko.utils.registerEventHandler(element, eventName, handler);
                    });

                    var updateFromModel;

                    if (isInputElement && element.type == "file") {
                        // For file input elements, can only write the empty string
                        updateFromModel = function () {
                            var newValue = ko.utils.unwrapObservable(valueAccessor());
                            if (newValue === null || newValue === undefined || newValue === "") {
                                element.value = "";
                            } else {
                                ko.dependencyDetection.ignore(valueUpdateHandler);  // reset the model to match the element
                            }
                        }
                    } else {
                        updateFromModel = function () {
                            var newValue = ko.utils.unwrapObservable(valueAccessor());
                            var elementValue = ko.selectExtensions.readValue(element);

                            if (elementValueBeforeEvent !== null && newValue === elementValueBeforeEvent) {
                                ko.utils.setTimeout(updateFromModel, 0);
                                return;
                            }

                            var valueHasChanged = newValue !== elementValue;

                            if (valueHasChanged || elementValue === undefined) {
                                if (tagName === "select") {
                                    var allowUnset = allBindings.get('valueAllowUnset');
                                    ko.selectExtensions.writeValue(element, newValue, allowUnset);
                                    if (!allowUnset && newValue !== ko.selectExtensions.readValue(element)) {
                                        // If you try to set a model value that can't be represented in an already-populated dropdown, reject that change,
                                        // because you're not allowed to have a model value that disagrees with a visible UI selection.
                                        ko.dependencyDetection.ignore(valueUpdateHandler);
                                    }
                                } else {
                                    ko.selectExtensions.writeValue(element, newValue);
                                }
                            }
                        };
                    }

                    if (tagName === "select") {
                        var updateFromModelComputed;
                        ko.bindingEvent.subscribe(element, ko.bindingEvent.childrenComplete, function () {
                            if (!updateFromModelComputed) {
                                ko.utils.registerEventHandler(element, "change", valueUpdateHandler);
                                updateFromModelComputed = ko.computed(updateFromModel, null, { disposeWhenNodeIsRemoved: element });
                            } else if (allBindings.get('valueAllowUnset')) {
                                updateFromModel();
                            } else {
                                valueUpdateHandler();
                            }
                        }, null, { 'notifyImmediately': true });
                    } else {
                        ko.utils.registerEventHandler(element, "change", valueUpdateHandler);
                        ko.computed(updateFromModel, null, { disposeWhenNodeIsRemoved: element });
                    }
                },
                'update': function () { } // Keep for backwards compatibility with code that may have wrapped value binding
            };
            ko.expressionRewriting.twoWayBindings['value'] = true;
            ko.bindingHandlers['visible'] = {
                'update': function (element, valueAccessor) {
                    var value = ko.utils.unwrapObservable(valueAccessor());
                    var isCurrentlyVisible = !(element.style.display == "none");
                    if (value && !isCurrentlyVisible)
                        element.style.display = "";
                    else if ((!value) && isCurrentlyVisible)
                        element.style.display = "none";
                }
            };

            ko.bindingHandlers['hidden'] = {
                'update': function (element, valueAccessor) {
                    ko.bindingHandlers['visible']['update'](element, function () { return !ko.utils.unwrapObservable(valueAccessor()) });
                }
            };
            // 'click' is just a shorthand for the usual full-length event:{click:handler}
            makeEventHandlerShortcut('click');
            // If you want to make a custom template engine,
            //
            // [1] Inherit from this class (like ko.nativeTemplateEngine does)
            // [2] Override 'renderTemplateSource', supplying a function with this signature:
            //
            //        function (templateSource, bindingContext, options) {
            //            // - templateSource.text() is the text of the template you should render
            //            // - bindingContext.$data is the data you should pass into the template
            //            //   - you might also want to make bindingContext.$parent, bindingContext.$parents,
            //            //     and bindingContext.$root available in the template too
            //            // - options gives you access to any other properties set on "data-bind: { template: options }"
            //            // - templateDocument is the document object of the template
            //            //
            //            // Return value: an array of DOM nodes
            //        }
            //
            // [3] Override 'createJavaScriptEvaluatorBlock', supplying a function with this signature:
            //
            //        function (script) {
            //            // Return value: Whatever syntax means "Evaluate the JavaScript statement 'script' and output the result"
            //            //               For example, the jquery.tmpl template engine converts 'someScript' to '${ someScript }'
            //        }
            //
            //     This is only necessary if you want to allow data-bind attributes to reference arbitrary template variables.
            //     If you don't want to allow that, you can set the property 'allowTemplateRewriting' to false (like ko.nativeTemplateEngine does)
            //     and then you don't need to override 'createJavaScriptEvaluatorBlock'.

            ko.templateEngine = function () { };

            ko.templateEngine.prototype['renderTemplateSource'] = function (templateSource, bindingContext, options, templateDocument) {
                throw new Error("Override renderTemplateSource");
            };

            ko.templateEngine.prototype['createJavaScriptEvaluatorBlock'] = function (script) {
                throw new Error("Override createJavaScriptEvaluatorBlock");
            };

            ko.templateEngine.prototype['makeTemplateSource'] = function (template, templateDocument) {
                // Named template
                if (typeof template == "string") {
                    templateDocument = templateDocument || document;
                    var elem = templateDocument.getElementById(template);
                    if (!elem)
                        throw new Error("Cannot find template with ID " + template);
                    return new ko.templateSources.domElement(elem);
                } else if ((template.nodeType == 1) || (template.nodeType == 8)) {
                    // Anonymous template
                    return new ko.templateSources.anonymousTemplate(template);
                } else
                    throw new Error("Unknown template type: " + template);
            };

            ko.templateEngine.prototype['renderTemplate'] = function (template, bindingContext, options, templateDocument) {
                var templateSource = this['makeTemplateSource'](template, templateDocument);
                return this['renderTemplateSource'](templateSource, bindingContext, options, templateDocument);
            };

            ko.templateEngine.prototype['isTemplateRewritten'] = function (template, templateDocument) {
                // Skip rewriting if requested
                if (this['allowTemplateRewriting'] === false)
                    return true;
                return this['makeTemplateSource'](template, templateDocument)['data']("isRewritten");
            };

            ko.templateEngine.prototype['rewriteTemplate'] = function (template, rewriterCallback, templateDocument) {
                var templateSource = this['makeTemplateSource'](template, templateDocument);
                var rewritten = rewriterCallback(templateSource['text']());
                templateSource['text'](rewritten);
                templateSource['data']("isRewritten", true);
            };

            ko.exportSymbol('templateEngine', ko.templateEngine);

            ko.templateRewriting = (function () {
                var memoizeDataBindingAttributeSyntaxRegex = /(<([a-z]+\d*)(?:\s+(?!data-bind\s*=\s*)[a-z0-9\-]+(?:=(?:\"[^\"]*\"|\'[^\']*\'|[^>]*))?)*\s+)data-bind\s*=\s*(["'])([\s\S]*?)\3/gi;
                var memoizeVirtualContainerBindingSyntaxRegex = /<!--\s*ko\b\s*([\s\S]*?)\s*-->/g;

                function validateDataBindValuesForRewriting(keyValueArray) {
                    var allValidators = ko.expressionRewriting.bindingRewriteValidators;
                    for (var i = 0; i < keyValueArray.length; i++) {
                        var key = keyValueArray[i]['key'];
                        if (Object.prototype.hasOwnProperty.call(allValidators, key)) {
                            var validator = allValidators[key];

                            if (typeof validator === "function") {
                                var possibleErrorMessage = validator(keyValueArray[i]['value']);
                                if (possibleErrorMessage)
                                    throw new Error(possibleErrorMessage);
                            } else if (!validator) {
                                throw new Error("This template engine does not support the '" + key + "' binding within its templates");
                            }
                        }
                    }
                }

                function constructMemoizedTagReplacement(dataBindAttributeValue, tagToRetain, nodeName, templateEngine) {
                    var dataBindKeyValueArray = ko.expressionRewriting.parseObjectLiteral(dataBindAttributeValue);
                    validateDataBindValuesForRewriting(dataBindKeyValueArray);
                    var rewrittenDataBindAttributeValue = ko.expressionRewriting.preProcessBindings(dataBindKeyValueArray, { 'valueAccessors': true });

                    // For no obvious reason, Opera fails to evaluate rewrittenDataBindAttributeValue unless it's wrapped in an additional
                    // anonymous function, even though Opera's built-in debugger can evaluate it anyway. No other browser requires this
                    // extra indirection.
                    var applyBindingsToNextSiblingScript =
                        "ko.__tr_ambtns(function($context,$element){return(function(){return{ " + rewrittenDataBindAttributeValue + " } })()},'" + nodeName.toLowerCase() + "')";
                    return templateEngine['createJavaScriptEvaluatorBlock'](applyBindingsToNextSiblingScript) + tagToRetain;
                }

                return {
                    ensureTemplateIsRewritten: function (template, templateEngine, templateDocument) {
                        if (!templateEngine['isTemplateRewritten'](template, templateDocument))
                            templateEngine['rewriteTemplate'](template, function (htmlString) {
                                return ko.templateRewriting.memoizeBindingAttributeSyntax(htmlString, templateEngine);
                            }, templateDocument);
                    },

                    memoizeBindingAttributeSyntax: function (htmlString, templateEngine) {
                        return htmlString.replace(memoizeDataBindingAttributeSyntaxRegex, function () {
                            return constructMemoizedTagReplacement(/* dataBindAttributeValue: */ arguments[4], /* tagToRetain: */ arguments[1], /* nodeName: */ arguments[2], templateEngine);
                        }).replace(memoizeVirtualContainerBindingSyntaxRegex, function () {
                            return constructMemoizedTagReplacement(/* dataBindAttributeValue: */ arguments[1], /* tagToRetain: */ "<!-- ko -->", /* nodeName: */ "#comment", templateEngine);
                        });
                    },

                    applyMemoizedBindingsToNextSibling: function (bindings, nodeName) {
                        return ko.memoization.memoize(function (domNode, bindingContext) {
                            var nodeToBind = domNode.nextSibling;
                            if (nodeToBind && nodeToBind.nodeName.toLowerCase() === nodeName) {
                                ko.applyBindingAccessorsToNode(nodeToBind, bindings, bindingContext);
                            }
                        });
                    }
                }
            })();


            // Exported only because it has to be referenced by string lookup from within rewritten template
            ko.exportSymbol('__tr_ambtns', ko.templateRewriting.applyMemoizedBindingsToNextSibling);
            (function () {
                // A template source represents a read/write way of accessing a template. This is to eliminate the need for template loading/saving
                // logic to be duplicated in every template engine (and means they can all work with anonymous templates, etc.)
                //
                // Two are provided by default:
                //  1. ko.templateSources.domElement       - reads/writes the text content of an arbitrary DOM element
                //  2. ko.templateSources.anonymousElement - uses ko.utils.domData to read/write text *associated* with the DOM element, but
                //                                           without reading/writing the actual element text content, since it will be overwritten
                //                                           with the rendered template output.
                // You can implement your own template source if you want to fetch/store templates somewhere other than in DOM elements.
                // Template sources need to have the following functions:
                //   text() 			- returns the template text from your storage location
                //   text(value)		- writes the supplied template text to your storage location
                //   data(key)			- reads values stored using data(key, value) - see below
                //   data(key, value)	- associates "value" with this template and the key "key". Is used to store information like "isRewritten".
                //
                // Optionally, template sources can also have the following functions:
                //   nodes()            - returns a DOM element containing the nodes of this template, where available
                //   nodes(value)       - writes the given DOM element to your storage location
                // If a DOM element is available for a given template source, template engines are encouraged to use it in preference over text()
                // for improved speed. However, all templateSources must supply text() even if they don't supply nodes().
                //
                // Once you've implemented a templateSource, make your template engine use it by subclassing whatever template engine you were
                // using and overriding "makeTemplateSource" to return an instance of your custom template source.

                ko.templateSources = {};

                // ---- ko.templateSources.domElement -----

                // template types
                var templateScript = 1,
                    templateTextArea = 2,
                    templateTemplate = 3,
                    templateElement = 4;

                ko.templateSources.domElement = function (element) {
                    this.domElement = element;

                    if (element) {
                        var tagNameLower = ko.utils.tagNameLower(element);
                        this.templateType =
                            tagNameLower === "script" ? templateScript :
                                tagNameLower === "textarea" ? templateTextArea :
                                    // For browsers with proper <template> element support, where the .content property gives a document fragment
                                    tagNameLower == "template" && element.content && element.content.nodeType === 11 ? templateTemplate :
                                        templateElement;
                    }
                }

                ko.templateSources.domElement.prototype['text'] = function (/* valueToWrite */) {
                    var elemContentsProperty = this.templateType === templateScript ? "text"
                        : this.templateType === templateTextArea ? "value"
                            : "innerHTML";

                    if (arguments.length == 0) {
                        return this.domElement[elemContentsProperty];
                    } else {
                        var valueToWrite = arguments[0];
                        if (elemContentsProperty === "innerHTML")
                            ko.utils.setHtml(this.domElement, valueToWrite);
                        else
                            this.domElement[elemContentsProperty] = valueToWrite;
                    }
                };

                var dataDomDataPrefix = ko.utils.domData.nextKey() + "_";
                ko.templateSources.domElement.prototype['data'] = function (key /*, valueToWrite */) {
                    if (arguments.length === 1) {
                        return ko.utils.domData.get(this.domElement, dataDomDataPrefix + key);
                    } else {
                        ko.utils.domData.set(this.domElement, dataDomDataPrefix + key, arguments[1]);
                    }
                };

                var templatesDomDataKey = ko.utils.domData.nextKey();
                function getTemplateDomData(element) {
                    return ko.utils.domData.get(element, templatesDomDataKey) || {};
                }
                function setTemplateDomData(element, data) {
                    ko.utils.domData.set(element, templatesDomDataKey, data);
                }

                ko.templateSources.domElement.prototype['nodes'] = function (/* valueToWrite */) {
                    var element = this.domElement;
                    if (arguments.length == 0) {
                        var templateData = getTemplateDomData(element),
                            nodes = templateData.containerData || (
                                this.templateType === templateTemplate ? element.content :
                                    this.templateType === templateElement ? element :
                                        undefined);
                        if (!nodes || templateData.alwaysCheckText) {
                            // If the template is associated with an element that stores the template as text,
                            // parse and cache the nodes whenever there's new text content available. This allows
                            // the user to update the template content by updating the text of template node.
                            var text = this['text']();
                            if (text && text !== templateData.textData) {
                                nodes = ko.utils.parseHtmlForTemplateNodes(text, element.ownerDocument);
                                setTemplateDomData(element, { containerData: nodes, textData: text, alwaysCheckText: true });
                            }
                        }
                        return nodes;
                    } else {
                        var valueToWrite = arguments[0];
                        if (this.templateType !== undefined) {
                            this['text']("");   // clear the text from the node
                        }
                        setTemplateDomData(element, { containerData: valueToWrite });
                    }
                };

                // ---- ko.templateSources.anonymousTemplate -----
                // Anonymous templates are normally saved/retrieved as DOM nodes through "nodes".
                // For compatibility, you can also read "text"; it will be serialized from the nodes on demand.
                // Writing to "text" is still supported, but then the template data will not be available as DOM nodes.

                ko.templateSources.anonymousTemplate = function (element) {
                    this.domElement = element;
                }
                ko.templateSources.anonymousTemplate.prototype = new ko.templateSources.domElement();
                ko.templateSources.anonymousTemplate.prototype.constructor = ko.templateSources.anonymousTemplate;
                ko.templateSources.anonymousTemplate.prototype['text'] = function (/* valueToWrite */) {
                    if (arguments.length == 0) {
                        var templateData = getTemplateDomData(this.domElement);
                        if (templateData.textData === undefined && templateData.containerData)
                            templateData.textData = templateData.containerData.innerHTML;
                        return templateData.textData;
                    } else {
                        var valueToWrite = arguments[0];
                        setTemplateDomData(this.domElement, { textData: valueToWrite });
                    }
                };

                ko.exportSymbol('templateSources', ko.templateSources);
                ko.exportSymbol('templateSources.domElement', ko.templateSources.domElement);
                ko.exportSymbol('templateSources.anonymousTemplate', ko.templateSources.anonymousTemplate);
            })();
            (function () {
                var _templateEngine;
                ko.setTemplateEngine = function (templateEngine) {
                    if ((templateEngine != undefined) && !(templateEngine instanceof ko.templateEngine))
                        throw new Error("templateEngine must inherit from ko.templateEngine");
                    _templateEngine = templateEngine;
                }

                function invokeForEachNodeInContinuousRange(firstNode, lastNode, action) {
                    var node, nextInQueue = firstNode, firstOutOfRangeNode = ko.virtualElements.nextSibling(lastNode);
                    while (nextInQueue && ((node = nextInQueue) !== firstOutOfRangeNode)) {
                        nextInQueue = ko.virtualElements.nextSibling(node);
                        action(node, nextInQueue);
                    }
                }

                function activateBindingsOnContinuousNodeArray(continuousNodeArray, bindingContext) {
                    // To be used on any nodes that have been rendered by a template and have been inserted into some parent element
                    // Walks through continuousNodeArray (which *must* be continuous, i.e., an uninterrupted sequence of sibling nodes, because
                    // the algorithm for walking them relies on this), and for each top-level item in the virtual-element sense,
                    // (1) Does a regular "applyBindings" to associate bindingContext with this node and to activate any non-memoized bindings
                    // (2) Unmemoizes any memos in the DOM subtree (e.g., to activate bindings that had been memoized during template rewriting)

                    if (continuousNodeArray.length) {
                        var firstNode = continuousNodeArray[0],
                            lastNode = continuousNodeArray[continuousNodeArray.length - 1],
                            parentNode = firstNode.parentNode,
                            provider = ko.bindingProvider['instance'],
                            preprocessNode = provider['preprocessNode'];

                        if (preprocessNode) {
                            invokeForEachNodeInContinuousRange(firstNode, lastNode, function (node, nextNodeInRange) {
                                var nodePreviousSibling = node.previousSibling;
                                var newNodes = preprocessNode.call(provider, node);
                                if (newNodes) {
                                    if (node === firstNode)
                                        firstNode = newNodes[0] || nextNodeInRange;
                                    if (node === lastNode)
                                        lastNode = newNodes[newNodes.length - 1] || nodePreviousSibling;
                                }
                            });

                            // Because preprocessNode can change the nodes, including the first and last nodes, update continuousNodeArray to match.
                            // We need the full set, including inner nodes, because the unmemoize step might remove the first node (and so the real
                            // first node needs to be in the array).
                            continuousNodeArray.length = 0;
                            if (!firstNode) { // preprocessNode might have removed all the nodes, in which case there's nothing left to do
                                return;
                            }
                            if (firstNode === lastNode) {
                                continuousNodeArray.push(firstNode);
                            } else {
                                continuousNodeArray.push(firstNode, lastNode);
                                ko.utils.fixUpContinuousNodeArray(continuousNodeArray, parentNode);
                            }
                        }

                        // Need to applyBindings *before* unmemoziation, because unmemoization might introduce extra nodes (that we don't want to re-bind)
                        // whereas a regular applyBindings won't introduce new memoized nodes
                        invokeForEachNodeInContinuousRange(firstNode, lastNode, function (node) {
                            if (node.nodeType === 1 || node.nodeType === 8)
                                ko.applyBindings(bindingContext, node);
                        });
                        invokeForEachNodeInContinuousRange(firstNode, lastNode, function (node) {
                            if (node.nodeType === 1 || node.nodeType === 8)
                                ko.memoization.unmemoizeDomNodeAndDescendants(node, [bindingContext]);
                        });

                        // Make sure any changes done by applyBindings or unmemoize are reflected in the array
                        ko.utils.fixUpContinuousNodeArray(continuousNodeArray, parentNode);
                    }
                }

                function getFirstNodeFromPossibleArray(nodeOrNodeArray) {
                    return nodeOrNodeArray.nodeType ? nodeOrNodeArray
                        : nodeOrNodeArray.length > 0 ? nodeOrNodeArray[0]
                            : null;
                }

                function executeTemplate(targetNodeOrNodeArray, renderMode, template, bindingContext, options) {
                    options = options || {};
                    var firstTargetNode = targetNodeOrNodeArray && getFirstNodeFromPossibleArray(targetNodeOrNodeArray);
                    var templateDocument = (firstTargetNode || template || {}).ownerDocument;
                    var templateEngineToUse = (options['templateEngine'] || _templateEngine);
                    ko.templateRewriting.ensureTemplateIsRewritten(template, templateEngineToUse, templateDocument);
                    var renderedNodesArray = templateEngineToUse['renderTemplate'](template, bindingContext, options, templateDocument);

                    // Loosely check result is an array of DOM nodes
                    if ((typeof renderedNodesArray.length != "number") || (renderedNodesArray.length > 0 && typeof renderedNodesArray[0].nodeType != "number"))
                        throw new Error("Template engine must return an array of DOM nodes");

                    var haveAddedNodesToParent = false;
                    switch (renderMode) {
                        case "replaceChildren":
                            ko.virtualElements.setDomNodeChildren(targetNodeOrNodeArray, renderedNodesArray);
                            haveAddedNodesToParent = true;
                            break;
                        case "replaceNode":
                            ko.utils.replaceDomNodes(targetNodeOrNodeArray, renderedNodesArray);
                            haveAddedNodesToParent = true;
                            break;
                        case "ignoreTargetNode": break;
                        default:
                            throw new Error("Unknown renderMode: " + renderMode);
                    }

                    if (haveAddedNodesToParent) {
                        activateBindingsOnContinuousNodeArray(renderedNodesArray, bindingContext);
                        if (options['afterRender']) {
                            ko.dependencyDetection.ignore(options['afterRender'], null, [renderedNodesArray, bindingContext[options['as'] || '$data']]);
                        }
                        if (renderMode == "replaceChildren") {
                            ko.bindingEvent.notify(targetNodeOrNodeArray, ko.bindingEvent.childrenComplete);
                        }
                    }

                    return renderedNodesArray;
                }

                function resolveTemplateName(template, data, context) {
                    // The template can be specified as:
                    if (ko.isObservable(template)) {
                        // 1. An observable, with string value
                        return template();
                    } else if (typeof template === 'function') {
                        // 2. A function of (data, context) returning a string
                        return template(data, context);
                    } else {
                        // 3. A string
                        return template;
                    }
                }

                ko.renderTemplate = function (template, dataOrBindingContext, options, targetNodeOrNodeArray, renderMode) {
                    options = options || {};
                    if ((options['templateEngine'] || _templateEngine) == undefined)
                        throw new Error("Set a template engine before calling renderTemplate");
                    renderMode = renderMode || "replaceChildren";

                    if (targetNodeOrNodeArray) {
                        var firstTargetNode = getFirstNodeFromPossibleArray(targetNodeOrNodeArray);

                        var whenToDispose = function () { return (!firstTargetNode) || !ko.utils.domNodeIsAttachedToDocument(firstTargetNode); }; // Passive disposal (on next evaluation)
                        var activelyDisposeWhenNodeIsRemoved = (firstTargetNode && renderMode == "replaceNode") ? firstTargetNode.parentNode : firstTargetNode;

                        return ko.dependentObservable( // So the DOM is automatically updated when any dependency changes
                            function () {
                                // Ensure we've got a proper binding context to work with
                                var bindingContext = (dataOrBindingContext && (dataOrBindingContext instanceof ko.bindingContext))
                                    ? dataOrBindingContext
                                    : new ko.bindingContext(dataOrBindingContext, null, null, null, { "exportDependencies": true });

                                var templateName = resolveTemplateName(template, bindingContext['$data'], bindingContext),
                                    renderedNodesArray = executeTemplate(targetNodeOrNodeArray, renderMode, templateName, bindingContext, options);

                                if (renderMode == "replaceNode") {
                                    targetNodeOrNodeArray = renderedNodesArray;
                                    firstTargetNode = getFirstNodeFromPossibleArray(targetNodeOrNodeArray);
                                }
                            },
                            null,
                            { disposeWhen: whenToDispose, disposeWhenNodeIsRemoved: activelyDisposeWhenNodeIsRemoved }
                        );
                    } else {
                        // We don't yet have a DOM node to evaluate, so use a memo and render the template later when there is a DOM node
                        return ko.memoization.memoize(function (domNode) {
                            ko.renderTemplate(template, dataOrBindingContext, options, domNode, "replaceNode");
                        });
                    }
                };

                ko.renderTemplateForEach = function (template, arrayOrObservableArray, options, targetNode, parentBindingContext) {
                    // Since setDomNodeChildrenFromArrayMapping always calls executeTemplateForArrayItem and then
                    // activateBindingsCallback for added items, we can store the binding context in the former to use in the latter.
                    var arrayItemContext, asName = options['as'];

                    // This will be called by setDomNodeChildrenFromArrayMapping to get the nodes to add to targetNode
                    var executeTemplateForArrayItem = function (arrayValue, index) {
                        // Support selecting template as a function of the data being rendered
                        arrayItemContext = parentBindingContext['createChildContext'](arrayValue, {
                            'as': asName,
                            'noChildContext': options['noChildContext'],
                            'extend': function (context) {
                                context['$index'] = index;
                                if (asName) {
                                    context[asName + "Index"] = index;
                                }
                            }
                        });

                        var templateName = resolveTemplateName(template, arrayValue, arrayItemContext);
                        return executeTemplate(targetNode, "ignoreTargetNode", templateName, arrayItemContext, options);
                    };

                    // This will be called whenever setDomNodeChildrenFromArrayMapping has added nodes to targetNode
                    var activateBindingsCallback = function (arrayValue, addedNodesArray, index) {
                        activateBindingsOnContinuousNodeArray(addedNodesArray, arrayItemContext);
                        if (options['afterRender'])
                            options['afterRender'](addedNodesArray, arrayValue);

                        // release the "cache" variable, so that it can be collected by
                        // the GC when its value isn't used from within the bindings anymore.
                        arrayItemContext = null;
                    };

                    var setDomNodeChildrenFromArrayMapping = function (newArray, changeList) {
                        // Call setDomNodeChildrenFromArrayMapping, ignoring any observables unwrapped within (most likely from a callback function).
                        // If the array items are observables, though, they will be unwrapped in executeTemplateForArrayItem and managed within setDomNodeChildrenFromArrayMapping.
                        ko.dependencyDetection.ignore(ko.utils.setDomNodeChildrenFromArrayMapping, null, [targetNode, newArray, executeTemplateForArrayItem, options, activateBindingsCallback, changeList]);
                        ko.bindingEvent.notify(targetNode, ko.bindingEvent.childrenComplete);
                    };

                    var shouldHideDestroyed = (options['includeDestroyed'] === false) || (ko.options['foreachHidesDestroyed'] && !options['includeDestroyed']);

                    if (!shouldHideDestroyed && !options['beforeRemove'] && ko.isObservableArray(arrayOrObservableArray)) {
                        setDomNodeChildrenFromArrayMapping(arrayOrObservableArray.peek());

                        var subscription = arrayOrObservableArray.subscribe(function (changeList) {
                            setDomNodeChildrenFromArrayMapping(arrayOrObservableArray(), changeList);
                        }, null, "arrayChange");
                        subscription.disposeWhenNodeIsRemoved(targetNode);

                        return subscription;
                    } else {
                        return ko.dependentObservable(function () {
                            var unwrappedArray = ko.utils.unwrapObservable(arrayOrObservableArray) || [];
                            if (typeof unwrappedArray.length == "undefined") // Coerce single value into array
                                unwrappedArray = [unwrappedArray];

                            if (shouldHideDestroyed) {
                                // Filter out any entries marked as destroyed
                                unwrappedArray = ko.utils.arrayFilter(unwrappedArray, function (item) {
                                    return item === undefined || item === null || !ko.utils.unwrapObservable(item['_destroy']);
                                });
                            }
                            setDomNodeChildrenFromArrayMapping(unwrappedArray);

                        }, null, { disposeWhenNodeIsRemoved: targetNode });
                    }
                };

                var templateComputedDomDataKey = ko.utils.domData.nextKey();
                function disposeOldComputedAndStoreNewOne(element, newComputed) {
                    var oldComputed = ko.utils.domData.get(element, templateComputedDomDataKey);
                    if (oldComputed && (typeof (oldComputed.dispose) == 'function'))
                        oldComputed.dispose();
                    ko.utils.domData.set(element, templateComputedDomDataKey, (newComputed && (!newComputed.isActive || newComputed.isActive())) ? newComputed : undefined);
                }

                var cleanContainerDomDataKey = ko.utils.domData.nextKey();
                ko.bindingHandlers['template'] = {
                    'init': function (element, valueAccessor) {
                        // Support anonymous templates
                        var bindingValue = ko.utils.unwrapObservable(valueAccessor());
                        if (typeof bindingValue == "string" || 'name' in bindingValue) {
                            // It's a named template - clear the element
                            ko.virtualElements.emptyNode(element);
                        } else if ('nodes' in bindingValue) {
                            // We've been given an array of DOM nodes. Save them as the template source.
                            // There is no known use case for the node array being an observable array (if the output
                            // varies, put that behavior *into* your template - that's what templates are for), and
                            // the implementation would be a mess, so assert that it's not observable.
                            var nodes = bindingValue['nodes'] || [];
                            if (ko.isObservable(nodes)) {
                                throw new Error('The "nodes" option must be a plain, non-observable array.');
                            }

                            // If the nodes are already attached to a KO-generated container, we reuse that container without moving the
                            // elements to a new one (we check only the first node, as the nodes are always moved together)
                            var container = nodes[0] && nodes[0].parentNode;
                            if (!container || !ko.utils.domData.get(container, cleanContainerDomDataKey)) {
                                container = ko.utils.moveCleanedNodesToContainerElement(nodes);
                                ko.utils.domData.set(container, cleanContainerDomDataKey, true);
                            }

                            new ko.templateSources.anonymousTemplate(element)['nodes'](container);
                        } else {
                            // It's an anonymous template - store the element contents, then clear the element
                            var templateNodes = ko.virtualElements.childNodes(element);
                            if (templateNodes.length > 0) {
                                var container = ko.utils.moveCleanedNodesToContainerElement(templateNodes); // This also removes the nodes from their current parent
                                new ko.templateSources.anonymousTemplate(element)['nodes'](container);
                            } else {
                                throw new Error("Anonymous template defined, but no template content was provided");
                            }
                        }
                        return { 'controlsDescendantBindings': true };
                    },
                    'update': function (element, valueAccessor, allBindings, viewModel, bindingContext) {
                        var value = valueAccessor(),
                            options = ko.utils.unwrapObservable(value),
                            shouldDisplay = true,
                            templateComputed = null,
                            template;

                        if (typeof options == "string") {
                            template = value;
                            options = {};
                        } else {
                            template = 'name' in options ? options['name'] : element;

                            // Support "if"/"ifnot" conditions
                            if ('if' in options)
                                shouldDisplay = ko.utils.unwrapObservable(options['if']);
                            if (shouldDisplay && 'ifnot' in options)
                                shouldDisplay = !ko.utils.unwrapObservable(options['ifnot']);

                            // Don't show anything if an empty name is given (see #2446)
                            if (shouldDisplay && !template) {
                                shouldDisplay = false;
                            }
                        }

                        if ('foreach' in options) {
                            // Render once for each data point (treating data set as empty if shouldDisplay==false)
                            var dataArray = (shouldDisplay && options['foreach']) || [];
                            templateComputed = ko.renderTemplateForEach(template, dataArray, options, element, bindingContext);
                        } else if (!shouldDisplay) {
                            ko.virtualElements.emptyNode(element);
                        } else {
                            // Render once for this single data point (or use the viewModel if no data was provided)
                            var innerBindingContext = bindingContext;
                            if ('data' in options) {
                                innerBindingContext = bindingContext['createChildContext'](options['data'], {
                                    'as': options['as'],
                                    'noChildContext': options['noChildContext'],
                                    'exportDependencies': true
                                });
                            }
                            templateComputed = ko.renderTemplate(template, innerBindingContext, options, element);
                        }

                        // It only makes sense to have a single template computed per element (otherwise which one should have its output displayed?)
                        disposeOldComputedAndStoreNewOne(element, templateComputed);
                    }
                };

                // Anonymous templates can't be rewritten. Give a nice error message if you try to do it.
                ko.expressionRewriting.bindingRewriteValidators['template'] = function (bindingValue) {
                    var parsedBindingValue = ko.expressionRewriting.parseObjectLiteral(bindingValue);

                    if ((parsedBindingValue.length == 1) && parsedBindingValue[0]['unknown'])
                        return null; // It looks like a string literal, not an object literal, so treat it as a named template (which is allowed for rewriting)

                    if (ko.expressionRewriting.keyValueArrayContainsKey(parsedBindingValue, "name"))
                        return null; // Named templates can be rewritten, so return "no error"
                    return "This template engine does not support anonymous templates nested within its templates";
                };

                ko.virtualElements.allowedBindings['template'] = true;
            })();

            ko.exportSymbol('setTemplateEngine', ko.setTemplateEngine);
            ko.exportSymbol('renderTemplate', ko.renderTemplate);
            // Go through the items that have been added and deleted and try to find matches between them.
            ko.utils.findMovesInArrayComparison = function (left, right, limitFailedCompares) {
                if (left.length && right.length) {
                    var failedCompares, l, r, leftItem, rightItem;
                    for (failedCompares = l = 0; (!limitFailedCompares || failedCompares < limitFailedCompares) && (leftItem = left[l]); ++l) {
                        for (r = 0; rightItem = right[r]; ++r) {
                            if (leftItem['value'] === rightItem['value']) {
                                leftItem['moved'] = rightItem['index'];
                                rightItem['moved'] = leftItem['index'];
                                right.splice(r, 1);         // This item is marked as moved; so remove it from right list
                                failedCompares = r = 0;     // Reset failed compares count because we're checking for consecutive failures
                                break;
                            }
                        }
                        failedCompares += r;
                    }
                }
            };

            ko.utils.compareArrays = (function () {
                var statusNotInOld = 'added', statusNotInNew = 'deleted';

                // Simple calculation based on Levenshtein distance.
                function compareArrays(oldArray, newArray, options) {
                    // For backward compatibility, if the third arg is actually a bool, interpret
                    // it as the old parameter 'dontLimitMoves'. Newer code should use { dontLimitMoves: true }.
                    options = (typeof options === 'boolean') ? { 'dontLimitMoves': options } : (options || {});
                    oldArray = oldArray || [];
                    newArray = newArray || [];

                    if (oldArray.length < newArray.length)
                        return compareSmallArrayToBigArray(oldArray, newArray, statusNotInOld, statusNotInNew, options);
                    else
                        return compareSmallArrayToBigArray(newArray, oldArray, statusNotInNew, statusNotInOld, options);
                }

                function compareSmallArrayToBigArray(smlArray, bigArray, statusNotInSml, statusNotInBig, options) {
                    var myMin = Math.min,
                        myMax = Math.max,
                        editDistanceMatrix = [],
                        smlIndex, smlIndexMax = smlArray.length,
                        bigIndex, bigIndexMax = bigArray.length,
                        compareRange = (bigIndexMax - smlIndexMax) || 1,
                        maxDistance = smlIndexMax + bigIndexMax + 1,
                        thisRow, lastRow,
                        bigIndexMaxForRow, bigIndexMinForRow;

                    for (smlIndex = 0; smlIndex <= smlIndexMax; smlIndex++) {
                        lastRow = thisRow;
                        editDistanceMatrix.push(thisRow = []);
                        bigIndexMaxForRow = myMin(bigIndexMax, smlIndex + compareRange);
                        bigIndexMinForRow = myMax(0, smlIndex - 1);
                        for (bigIndex = bigIndexMinForRow; bigIndex <= bigIndexMaxForRow; bigIndex++) {
                            if (!bigIndex)
                                thisRow[bigIndex] = smlIndex + 1;
                            else if (!smlIndex)  // Top row - transform empty array into new array via additions
                                thisRow[bigIndex] = bigIndex + 1;
                            else if (smlArray[smlIndex - 1] === bigArray[bigIndex - 1])
                                thisRow[bigIndex] = lastRow[bigIndex - 1];                  // copy value (no edit)
                            else {
                                var northDistance = lastRow[bigIndex] || maxDistance;       // not in big (deletion)
                                var westDistance = thisRow[bigIndex - 1] || maxDistance;    // not in small (addition)
                                thisRow[bigIndex] = myMin(northDistance, westDistance) + 1;
                            }
                        }
                    }

                    var editScript = [], meMinusOne, notInSml = [], notInBig = [];
                    for (smlIndex = smlIndexMax, bigIndex = bigIndexMax; smlIndex || bigIndex;) {
                        meMinusOne = editDistanceMatrix[smlIndex][bigIndex] - 1;
                        if (bigIndex && meMinusOne === editDistanceMatrix[smlIndex][bigIndex - 1]) {
                            notInSml.push(editScript[editScript.length] = {     // added
                                'status': statusNotInSml,
                                'value': bigArray[--bigIndex],
                                'index': bigIndex
                            });
                        } else if (smlIndex && meMinusOne === editDistanceMatrix[smlIndex - 1][bigIndex]) {
                            notInBig.push(editScript[editScript.length] = {     // deleted
                                'status': statusNotInBig,
                                'value': smlArray[--smlIndex],
                                'index': smlIndex
                            });
                        } else {
                            --bigIndex;
                            --smlIndex;
                            if (!options['sparse']) {
                                editScript.push({
                                    'status': "retained",
                                    'value': bigArray[bigIndex]
                                });
                            }
                        }
                    }

                    // Set a limit on the number of consecutive non-matching comparisons; having it a multiple of
                    // smlIndexMax keeps the time complexity of this algorithm linear.
                    ko.utils.findMovesInArrayComparison(notInBig, notInSml, !options['dontLimitMoves'] && smlIndexMax * 10);

                    return editScript.reverse();
                }

                return compareArrays;
            })();

            ko.exportSymbol('utils.compareArrays', ko.utils.compareArrays);
            (function () {
                // Objective:
                // * Given an input array, a container DOM node, and a function from array elements to arrays of DOM nodes,
                //   map the array elements to arrays of DOM nodes, concatenate together all these arrays, and use them to populate the container DOM node
                // * Next time we're given the same combination of things (with the array possibly having mutated), update the container DOM node
                //   so that its children is again the concatenation of the mappings of the array elements, but don't re-map any array elements that we
                //   previously mapped - retain those nodes, and just insert/delete other ones

                // "callbackAfterAddingNodes" will be invoked after any "mapping"-generated nodes are inserted into the container node
                // You can use this, for example, to activate bindings on those nodes.

                function mapNodeAndRefreshWhenChanged(containerNode, mapping, valueToMap, callbackAfterAddingNodes, index) {
                    // Map this array value inside a dependentObservable so we re-map when any dependency changes
                    var mappedNodes = [];
                    var dependentObservable = ko.dependentObservable(function () {
                        var newMappedNodes = mapping(valueToMap, index, ko.utils.fixUpContinuousNodeArray(mappedNodes, containerNode)) || [];

                        // On subsequent evaluations, just replace the previously-inserted DOM nodes
                        if (mappedNodes.length > 0) {
                            ko.utils.replaceDomNodes(mappedNodes, newMappedNodes);
                            if (callbackAfterAddingNodes)
                                ko.dependencyDetection.ignore(callbackAfterAddingNodes, null, [valueToMap, newMappedNodes, index]);
                        }

                        // Replace the contents of the mappedNodes array, thereby updating the record
                        // of which nodes would be deleted if valueToMap was itself later removed
                        mappedNodes.length = 0;
                        ko.utils.arrayPushAll(mappedNodes, newMappedNodes);
                    }, null, { disposeWhenNodeIsRemoved: containerNode, disposeWhen: function () { return !ko.utils.anyDomNodeIsAttachedToDocument(mappedNodes); } });
                    return { mappedNodes: mappedNodes, dependentObservable: (dependentObservable.isActive() ? dependentObservable : undefined) };
                }

                var lastMappingResultDomDataKey = ko.utils.domData.nextKey(),
                    deletedItemDummyValue = ko.utils.domData.nextKey();

                ko.utils.setDomNodeChildrenFromArrayMapping = function (domNode, array, mapping, options, callbackAfterAddingNodes, editScript) {
                    array = array || [];
                    if (typeof array.length == "undefined") // Coerce single value into array
                        array = [array];

                    options = options || {};
                    var lastMappingResult = ko.utils.domData.get(domNode, lastMappingResultDomDataKey);
                    var isFirstExecution = !lastMappingResult;

                    // Build the new mapping result
                    var newMappingResult = [];
                    var lastMappingResultIndex = 0;
                    var currentArrayIndex = 0;

                    var nodesToDelete = [];
                    var itemsToMoveFirstIndexes = [];
                    var itemsForBeforeRemoveCallbacks = [];
                    var itemsForMoveCallbacks = [];
                    var itemsForAfterAddCallbacks = [];
                    var mapData;
                    var countWaitingForRemove = 0;

                    function itemAdded(value) {
                        mapData = { arrayEntry: value, indexObservable: ko.observable(currentArrayIndex++) };
                        newMappingResult.push(mapData);
                        if (!isFirstExecution) {
                            itemsForAfterAddCallbacks.push(mapData);
                        }
                    }

                    function itemMovedOrRetained(oldPosition) {
                        mapData = lastMappingResult[oldPosition];
                        if (currentArrayIndex !== mapData.indexObservable.peek())
                            itemsForMoveCallbacks.push(mapData);
                        // Since updating the index might change the nodes, do so before calling fixUpContinuousNodeArray
                        mapData.indexObservable(currentArrayIndex++);
                        ko.utils.fixUpContinuousNodeArray(mapData.mappedNodes, domNode);
                        newMappingResult.push(mapData);
                    }

                    function callCallback(callback, items) {
                        if (callback) {
                            for (var i = 0, n = items.length; i < n; i++) {
                                ko.utils.arrayForEach(items[i].mappedNodes, function (node) {
                                    callback(node, i, items[i].arrayEntry);
                                });
                            }
                        }
                    }

                    if (isFirstExecution) {
                        ko.utils.arrayForEach(array, itemAdded);
                    } else {
                        if (!editScript || (lastMappingResult && lastMappingResult['_countWaitingForRemove'])) {
                            // Compare the provided array against the previous one
                            var lastArray = ko.utils.arrayMap(lastMappingResult, function (x) { return x.arrayEntry; }),
                                compareOptions = {
                                    'dontLimitMoves': options['dontLimitMoves'],
                                    'sparse': true
                                };
                            editScript = ko.utils.compareArrays(lastArray, array, compareOptions);
                        }

                        for (var i = 0, editScriptItem, movedIndex, itemIndex; editScriptItem = editScript[i]; i++) {
                            movedIndex = editScriptItem['moved'];
                            itemIndex = editScriptItem['index'];
                            switch (editScriptItem['status']) {
                                case "deleted":
                                    while (lastMappingResultIndex < itemIndex) {
                                        itemMovedOrRetained(lastMappingResultIndex++);
                                    }
                                    if (movedIndex === undefined) {
                                        mapData = lastMappingResult[lastMappingResultIndex];

                                        // Stop tracking changes to the mapping for these nodes
                                        if (mapData.dependentObservable) {
                                            mapData.dependentObservable.dispose();
                                            mapData.dependentObservable = undefined;
                                        }

                                        // Queue these nodes for later removal
                                        if (ko.utils.fixUpContinuousNodeArray(mapData.mappedNodes, domNode).length) {
                                            if (options['beforeRemove']) {
                                                newMappingResult.push(mapData);
                                                countWaitingForRemove++;
                                                if (mapData.arrayEntry === deletedItemDummyValue) {
                                                    mapData = null;
                                                } else {
                                                    itemsForBeforeRemoveCallbacks.push(mapData);
                                                }
                                            }
                                            if (mapData) {
                                                nodesToDelete.push.apply(nodesToDelete, mapData.mappedNodes);
                                            }
                                        }
                                    }
                                    lastMappingResultIndex++;
                                    break;

                                case "added":
                                    while (currentArrayIndex < itemIndex) {
                                        itemMovedOrRetained(lastMappingResultIndex++);
                                    }
                                    if (movedIndex !== undefined) {
                                        itemsToMoveFirstIndexes.push(newMappingResult.length);
                                        itemMovedOrRetained(movedIndex);
                                    } else {
                                        itemAdded(editScriptItem['value']);
                                    }
                                    break;
                            }
                        }

                        while (currentArrayIndex < array.length) {
                            itemMovedOrRetained(lastMappingResultIndex++);
                        }

                        // Record that the current view may still contain deleted items
                        // because it means we won't be able to use a provided editScript.
                        newMappingResult['_countWaitingForRemove'] = countWaitingForRemove;
                    }

                    // Store a copy of the array items we just considered so we can difference it next time
                    ko.utils.domData.set(domNode, lastMappingResultDomDataKey, newMappingResult);

                    // Call beforeMove first before any changes have been made to the DOM
                    callCallback(options['beforeMove'], itemsForMoveCallbacks);

                    // Next remove nodes for deleted items (or just clean if there's a beforeRemove callback)
                    ko.utils.arrayForEach(nodesToDelete, options['beforeRemove'] ? ko.cleanNode : ko.removeNode);

                    var i, j, lastNode, nodeToInsert, mappedNodes, activeElement;

                    // Since most browsers remove the focus from an element when it's moved to another location,
                    // save the focused element and try to restore it later.
                    try {
                        activeElement = domNode.ownerDocument.activeElement;
                    } catch (e) {
                        // IE9 throws if you access activeElement during page load (see issue #703)
                    }

                    // Try to reduce overall moved nodes by first moving the ones that were marked as moved by the edit script
                    if (itemsToMoveFirstIndexes.length) {
                        while ((i = itemsToMoveFirstIndexes.shift()) != undefined) {
                            mapData = newMappingResult[i];
                            for (lastNode = undefined; i;) {
                                if ((mappedNodes = newMappingResult[--i].mappedNodes) && mappedNodes.length) {
                                    lastNode = mappedNodes[mappedNodes.length - 1];
                                    break;
                                }
                            }
                            for (j = 0; nodeToInsert = mapData.mappedNodes[j]; lastNode = nodeToInsert, j++) {
                                ko.virtualElements.insertAfter(domNode, nodeToInsert, lastNode);
                            }
                        }
                    }

                    // Next add/reorder the remaining items (will include deleted items if there's a beforeRemove callback)
                    for (i = 0; mapData = newMappingResult[i]; i++) {
                        // Get nodes for newly added items
                        if (!mapData.mappedNodes)
                            ko.utils.extend(mapData, mapNodeAndRefreshWhenChanged(domNode, mapping, mapData.arrayEntry, callbackAfterAddingNodes, mapData.indexObservable));

                        // Put nodes in the right place if they aren't there already
                        for (j = 0; nodeToInsert = mapData.mappedNodes[j]; lastNode = nodeToInsert, j++) {
                            ko.virtualElements.insertAfter(domNode, nodeToInsert, lastNode);
                        }

                        // Run the callbacks for newly added nodes (for example, to apply bindings, etc.)
                        if (!mapData.initialized && callbackAfterAddingNodes) {
                            callbackAfterAddingNodes(mapData.arrayEntry, mapData.mappedNodes, mapData.indexObservable);
                            mapData.initialized = true;
                            lastNode = mapData.mappedNodes[mapData.mappedNodes.length - 1];     // get the last node again since it may have been changed by a preprocessor
                        }
                    }

                    // Restore the focused element if it had lost focus
                    if (activeElement && domNode.ownerDocument.activeElement != activeElement) {
                        activeElement.focus();
                    }

                    // If there's a beforeRemove callback, call it after reordering.
                    // Note that we assume that the beforeRemove callback will usually be used to remove the nodes using
                    // some sort of animation, which is why we first reorder the nodes that will be removed. If the
                    // callback instead removes the nodes right away, it would be more efficient to skip reordering them.
                    // Perhaps we'll make that change in the future if this scenario becomes more common.
                    callCallback(options['beforeRemove'], itemsForBeforeRemoveCallbacks);

                    // Replace the stored values of deleted items with a dummy value. This provides two benefits: it marks this item
                    // as already "removed" so we won't call beforeRemove for it again, and it ensures that the item won't match up
                    // with an actual item in the array and appear as "retained" or "moved".
                    for (i = 0; i < itemsForBeforeRemoveCallbacks.length; ++i) {
                        itemsForBeforeRemoveCallbacks[i].arrayEntry = deletedItemDummyValue;
                    }

                    // Finally call afterMove and afterAdd callbacks
                    callCallback(options['afterMove'], itemsForMoveCallbacks);
                    callCallback(options['afterAdd'], itemsForAfterAddCallbacks);
                }
            })();

            ko.exportSymbol('utils.setDomNodeChildrenFromArrayMapping', ko.utils.setDomNodeChildrenFromArrayMapping);
            ko.nativeTemplateEngine = function () {
                this['allowTemplateRewriting'] = false;
            }

            ko.nativeTemplateEngine.prototype = new ko.templateEngine();
            ko.nativeTemplateEngine.prototype.constructor = ko.nativeTemplateEngine;
            ko.nativeTemplateEngine.prototype['renderTemplateSource'] = function (templateSource, bindingContext, options, templateDocument) {
                var useNodesIfAvailable = !(ko.utils.ieVersion < 9), // IE<9 cloneNode doesn't work properly
                    templateNodesFunc = useNodesIfAvailable ? templateSource['nodes'] : null,
                    templateNodes = templateNodesFunc ? templateSource['nodes']() : null;

                if (templateNodes) {
                    return ko.utils.makeArray(templateNodes.cloneNode(true).childNodes);
                } else {
                    var templateText = templateSource['text']();
                    return ko.utils.parseHtmlFragment(templateText, templateDocument);
                }
            };

            ko.nativeTemplateEngine.instance = new ko.nativeTemplateEngine();
            ko.setTemplateEngine(ko.nativeTemplateEngine.instance);

            ko.exportSymbol('nativeTemplateEngine', ko.nativeTemplateEngine);
            (function () {
                ko.jqueryTmplTemplateEngine = function () {
                    // Detect which version of jquery-tmpl you're using. Unfortunately jquery-tmpl
                    // doesn't expose a version number, so we have to infer it.
                    // Note that as of Knockout 1.3, we only support jQuery.tmpl 1.0.0pre and later,
                    // which KO internally refers to as version "2", so older versions are no longer detected.
                    var jQueryTmplVersion = this.jQueryTmplVersion = (function () {
                        if (!jQueryInstance || !(jQueryInstance['tmpl']))
                            return 0;
                        // Since it exposes no official version number, we use our own numbering system. To be updated as jquery-tmpl evolves.
                        try {
                            if (jQueryInstance['tmpl']['tag']['tmpl']['open'].toString().indexOf('__') >= 0) {
                                // Since 1.0.0pre, custom tags should append markup to an array called "__"
                                return 2; // Final version of jquery.tmpl
                            }
                        } catch (ex) { /* Apparently not the version we were looking for */ }

                        return 1; // Any older version that we don't support
                    })();

                    function ensureHasReferencedJQueryTemplates() {
                        if (jQueryTmplVersion < 2)
                            throw new Error("Your version of jQuery.tmpl is too old. Please upgrade to jQuery.tmpl 1.0.0pre or later.");
                    }

                    function executeTemplate(compiledTemplate, data, jQueryTemplateOptions) {
                        return jQueryInstance['tmpl'](compiledTemplate, data, jQueryTemplateOptions);
                    }

                    this['renderTemplateSource'] = function (templateSource, bindingContext, options, templateDocument) {
                        templateDocument = templateDocument || document;
                        options = options || {};
                        ensureHasReferencedJQueryTemplates();

                        // Ensure we have stored a precompiled version of this template (don't want to reparse on every render)
                        var precompiled = templateSource['data']('precompiled');
                        if (!precompiled) {
                            var templateText = templateSource['text']() || "";
                            // Wrap in "with($whatever.koBindingContext) { ... }"
                            templateText = "{{ko_with $item.koBindingContext}}" + templateText + "{{/ko_with}}";

                            precompiled = jQueryInstance['template'](null, templateText);
                            templateSource['data']('precompiled', precompiled);
                        }

                        var data = [bindingContext['$data']]; // Prewrap the data in an array to stop jquery.tmpl from trying to unwrap any arrays
                        var jQueryTemplateOptions = jQueryInstance['extend']({ 'koBindingContext': bindingContext }, options['templateOptions']);

                        var resultNodes = executeTemplate(precompiled, data, jQueryTemplateOptions);
                        resultNodes['appendTo'](templateDocument.createElement("div")); // Using "appendTo" forces jQuery/jQuery.tmpl to perform necessary cleanup work

                        jQueryInstance['fragments'] = {}; // Clear jQuery's fragment cache to avoid a memory leak after a large number of template renders
                        return resultNodes;
                    };

                    this['createJavaScriptEvaluatorBlock'] = function (script) {
                        return "{{ko_code ((function() { return " + script + " })()) }}";
                    };

                    this['addTemplate'] = function (templateName, templateMarkup) {
                        document.write("<script type='text/html' id='" + templateName + "'>" + templateMarkup + "<" + "/script>");
                    };

                    if (jQueryTmplVersion > 0) {
                        jQueryInstance['tmpl']['tag']['ko_code'] = {
                            open: "__.push($1 || '');"
                        };
                        jQueryInstance['tmpl']['tag']['ko_with'] = {
                            open: "with($1) {",
                            close: "} "
                        };
                    }
                };

                ko.jqueryTmplTemplateEngine.prototype = new ko.templateEngine();
                ko.jqueryTmplTemplateEngine.prototype.constructor = ko.jqueryTmplTemplateEngine;

                // Use this one by default *only if jquery.tmpl is referenced*
                var jqueryTmplTemplateEngineInstance = new ko.jqueryTmplTemplateEngine();
                if (jqueryTmplTemplateEngineInstance.jQueryTmplVersion > 0)
                    ko.setTemplateEngine(jqueryTmplTemplateEngineInstance);

                ko.exportSymbol('jqueryTmplTemplateEngine', ko.jqueryTmplTemplateEngine);
            })();
        // }));
    // }());
// })();