0 , = [.w? "," .w?]
1 object = ["{" .w? .s?(, [.t? .w? ":" .w? value .w?]) "}"]
2 array = ["[" .w? .s?(, value) .w? "]"]
3 value = [{
    .t?
    .$
    object
    array
    "true"
    "false"
    "null"
}]
4 document = [.w? object .w?]