fson

FSON (Flexible Serialized Object Notation) is an extension for JSON that is used primarily for configuration. The user can quickly configure the configuration using references or a template strings.

Features

Comments and new values

/* Multiline comment */ [null, NaN, Infinity, -Infinity, 0x1ABC /*Hexadecimal*/] // Single comment

Identifiers

• You can use identifiers without quotes and with single quotes:

{
    "double quotes": null,
    'single quotes': null,
    withoutQuotes: null
}

References

• A reference is an object that can be anywhere (it can be either a pair of an object or it can be in an array) that can be referenced using it's identifier or path. For example:

{
  something: {
      key: #{ #id: "identifier"; #value: "value"; }
  }
}

• The reference in the example above can be referenced in two ways:
  • Using it's identifier: #identifier or #"identifier"
  • Using it's path: #/something/identifier or #/"something"/"identifier"

Template strings

• Template strings are strings enclosed in backticks. They allow you to embed other values (including references) in them using ${value}. For example:

  {
    x: 5,
    something: `x is ${x}`
  }
  

Other

• Objects and arrays can have a trailing comma: { x: { y: [], }, }
• Numbers can start with a plus: +1.5
• Strings can be multiline:

"hello
world"

• Whitespaces don't matter

Examples

See all examples in Examples directory.
How to run example: cargo run --example EXAMPLE_NAME

Compiling to WebAssembly

FSON is already ready for compilation to WebAssembly and already has the necessary functions. js-sys and wasm-bindgen libraries and functions are used only when compiling to WebAssembly.
Use these commands to compile to wasm:

# Install wasm-pack
cargo install wasm-pack

# Compile to wasm
wasm-pack build --target web

import init, { parse, stringify } from "./jsonparser.js";
init().then(() => {
  console.log(stringify({
    // Creating reference
    x: {
      "#id": "test",
      "#value": "value",
    },

    // Using reference
    y: [
      // Identifier
      { "#reference_id": "test" },

      // Path
      { "#reference_path": ["x"] },

      // Template string
      {
        "@template_string": [
          "test is ",
          { "#reference_id": "test" }, /* Reference */
          "; 2 + 2 = ",
          4, /* Normal value */
        ],
      },
    ],
  }));
});

License

MIT