235 lines
		
	
	
		
			7.5 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			235 lines
		
	
	
		
			7.5 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|  | # JSON5 – JSON for Humans
 | |||
|  | 
 | |||
|  | [][Build Status] | |||
|  | [][Coverage | |||
|  | Status] | |||
|  | 
 | |||
|  | The JSON5 Data Interchange Format (JSON5) is a superset of [JSON] that aims to | |||
|  | alleviate some of the limitations of JSON by expanding its syntax to include | |||
|  | some productions from [ECMAScript 5.1]. | |||
|  | 
 | |||
|  | This JavaScript library is the official reference implementation for JSON5 | |||
|  | parsing and serialization libraries. | |||
|  | 
 | |||
|  | [Build Status]: https://travis-ci.org/json5/json5 | |||
|  | 
 | |||
|  | [Coverage Status]: https://coveralls.io/github/json5/json5 | |||
|  | 
 | |||
|  | [JSON]: https://tools.ietf.org/html/rfc7159 | |||
|  | 
 | |||
|  | [ECMAScript 5.1]: https://www.ecma-international.org/ecma-262/5.1/ | |||
|  | 
 | |||
|  | ## Summary of Features
 | |||
|  | The following ECMAScript 5.1 features, which are not supported in JSON, have | |||
|  | been extended to JSON5. | |||
|  | 
 | |||
|  | ### Objects
 | |||
|  | - Object keys may be an ECMAScript 5.1 _[IdentifierName]_. | |||
|  | - Objects may have a single trailing comma. | |||
|  | 
 | |||
|  | ### Arrays
 | |||
|  | - Arrays may have a single trailing comma. | |||
|  | 
 | |||
|  | ### Strings
 | |||
|  | - Strings may be single quoted. | |||
|  | - Strings may span multiple lines by escaping new line characters. | |||
|  | - Strings may include character escapes. | |||
|  | 
 | |||
|  | ### Numbers
 | |||
|  | - Numbers may be hexadecimal. | |||
|  | - Numbers may have a leading or trailing decimal point. | |||
|  | - Numbers may be [IEEE 754] positive infinity, negative infinity, and NaN. | |||
|  | - Numbers may begin with an explicit plus sign. | |||
|  | 
 | |||
|  | ### Comments
 | |||
|  | - Single and multi-line comments are allowed. | |||
|  | 
 | |||
|  | ### White Space
 | |||
|  | - Additional white space characters are allowed. | |||
|  | 
 | |||
|  | [IdentifierName]: https://www.ecma-international.org/ecma-262/5.1/#sec-7.6 | |||
|  | 
 | |||
|  | [IEEE 754]: http://ieeexplore.ieee.org/servlet/opac?punumber=4610933 | |||
|  | 
 | |||
|  | ## Short Example
 | |||
|  | ```js | |||
|  | { | |||
|  |   // comments | |||
|  |   unquoted: 'and you can quote me on that', | |||
|  |   singleQuotes: 'I can use "double quotes" here', | |||
|  |   lineBreaks: "Look, Mom! \ | |||
|  | No \\n's!", | |||
|  |   hexadecimal: 0xdecaf, | |||
|  |   leadingDecimalPoint: .8675309, andTrailing: 8675309., | |||
|  |   positiveSign: +1, | |||
|  |   trailingComma: 'in objects', andIn: ['arrays',], | |||
|  |   "backwardsCompatible": "with JSON", | |||
|  | } | |||
|  | ``` | |||
|  | 
 | |||
|  | ## Specification
 | |||
|  | For a detailed explanation of the JSON5 format, please read the [official | |||
|  | specification](https://json5.github.io/json5-spec/). | |||
|  | 
 | |||
|  | ## Installation
 | |||
|  | ### Node.js
 | |||
|  | ```sh | |||
|  | npm install json5 | |||
|  | ``` | |||
|  | 
 | |||
|  | ```js | |||
|  | const JSON5 = require('json5') | |||
|  | ``` | |||
|  | 
 | |||
|  | ### Browsers
 | |||
|  | ```html | |||
|  | <script src="https://unpkg.com/json5@^2.0.0/dist/index.min.js"></script> | |||
|  | ``` | |||
|  | 
 | |||
|  | This will create a global `JSON5` variable. | |||
|  | 
 | |||
|  | ## API
 | |||
|  | The JSON5 API is compatible with the [JSON API]. | |||
|  | 
 | |||
|  | [JSON API]: | |||
|  | https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON | |||
|  | 
 | |||
|  | ### JSON5.parse()
 | |||
|  | Parses a JSON5 string, constructing the JavaScript value or object described by | |||
|  | the string. An optional reviver function can be provided to perform a | |||
|  | transformation on the resulting object before it is returned. | |||
|  | 
 | |||
|  | #### Syntax
 | |||
|  |     JSON5.parse(text[, reviver]) | |||
|  | 
 | |||
|  | #### Parameters
 | |||
|  | - `text`: The string to parse as JSON5. | |||
|  | - `reviver`: If a function, this prescribes how the value originally produced by | |||
|  |   parsing is transformed, before being returned. | |||
|  | 
 | |||
|  | #### Return value
 | |||
|  | The object corresponding to the given JSON5 text. | |||
|  | 
 | |||
|  | ### JSON5.stringify()
 | |||
|  | Converts a JavaScript value to a JSON5 string, optionally replacing values if a | |||
|  | replacer function is specified, or optionally including only the specified | |||
|  | properties if a replacer array is specified. | |||
|  | 
 | |||
|  | #### Syntax
 | |||
|  |     JSON5.stringify(value[, replacer[, space]]) | |||
|  |     JSON5.stringify(value[, options]) | |||
|  | 
 | |||
|  | #### Parameters
 | |||
|  | - `value`: The value to convert to a JSON5 string. | |||
|  | - `replacer`: A function that alters the behavior of the stringification | |||
|  |   process, or an array of String and Number objects that serve as a whitelist | |||
|  |   for selecting/filtering the properties of the value object to be included in | |||
|  |   the JSON5 string. If this value is null or not provided, all properties of the | |||
|  |   object are included in the resulting JSON5 string. | |||
|  | - `space`: A String or Number object that's used to insert white space into the | |||
|  |   output JSON5 string for readability purposes. If this is a Number, it | |||
|  |   indicates the number of space characters to use as white space; this number is | |||
|  |   capped at 10 (if it is greater, the value is just 10). Values less than 1 | |||
|  |   indicate that no space should be used. If this is a String, the string (or the | |||
|  |   first 10 characters of the string, if it's longer than that) is used as white | |||
|  |   space. If this parameter is not provided (or is null), no white space is used. | |||
|  |   If white space is used, trailing commas will be used in objects and arrays. | |||
|  | - `options`: An object with the following properties: | |||
|  |   - `replacer`: Same as the `replacer` parameter. | |||
|  |   - `space`: Same as the `space` parameter. | |||
|  |   - `quote`: A String representing the quote character to use when serializing | |||
|  |     strings. | |||
|  | 
 | |||
|  | #### Return value
 | |||
|  | A JSON5 string representing the value. | |||
|  | 
 | |||
|  | ### Node.js `require()` JSON5 files
 | |||
|  | When using Node.js, you can `require()` JSON5 files by adding the following | |||
|  | statement. | |||
|  | 
 | |||
|  | ```js | |||
|  | require('json5/lib/register') | |||
|  | ``` | |||
|  | 
 | |||
|  | Then you can load a JSON5 file with a Node.js `require()` statement. For | |||
|  | example: | |||
|  | 
 | |||
|  | ```js | |||
|  | const config = require('./config.json5') | |||
|  | ``` | |||
|  | 
 | |||
|  | ## CLI
 | |||
|  | Since JSON is more widely used than JSON5, this package includes a CLI for | |||
|  | converting JSON5 to JSON and for validating the syntax of JSON5 documents. | |||
|  | 
 | |||
|  | ### Installation
 | |||
|  | ```sh | |||
|  | npm install --global json5 | |||
|  | ``` | |||
|  | 
 | |||
|  | ### Usage
 | |||
|  | ```sh | |||
|  | json5 [options] <file> | |||
|  | ``` | |||
|  | 
 | |||
|  | If `<file>` is not provided, then STDIN is used. | |||
|  | 
 | |||
|  | #### Options:
 | |||
|  | - `-s`, `--space`: The number of spaces to indent or `t` for tabs | |||
|  | - `-o`, `--out-file [file]`: Output to the specified file, otherwise STDOUT | |||
|  | - `-v`, `--validate`: Validate JSON5 but do not output JSON | |||
|  | - `-V`, `--version`: Output the version number | |||
|  | - `-h`, `--help`: Output usage information | |||
|  | 
 | |||
|  | ## Contributing
 | |||
|  | ### Development
 | |||
|  | ```sh | |||
|  | git clone https://github.com/json5/json5 | |||
|  | cd json5 | |||
|  | npm install | |||
|  | ``` | |||
|  | 
 | |||
|  | When contributing code, please write relevant tests and run `npm test` and `npm | |||
|  | run lint` before submitting pull requests. Please use an editor that supports | |||
|  | [EditorConfig](http://editorconfig.org/). | |||
|  | 
 | |||
|  | ### Issues
 | |||
|  | To report bugs or request features regarding the JSON5 data format, please | |||
|  | submit an issue to the [official specification | |||
|  | repository](https://github.com/json5/json5-spec). | |||
|  | 
 | |||
|  | To report bugs or request features regarding the JavaScript implentation of | |||
|  | JSON5, please submit an issue to this repository. | |||
|  | 
 | |||
|  | ## License
 | |||
|  | MIT. See [LICENSE.md](./LICENSE.md) for details. | |||
|  | 
 | |||
|  | ## Credits
 | |||
|  | [Assem Kishore](https://github.com/aseemk) founded this project. | |||
|  | 
 | |||
|  | [Michael Bolin](http://bolinfest.com/) independently arrived at and published | |||
|  | some of these same ideas with awesome explanations and detail. Recommended | |||
|  | reading: [Suggested Improvements to JSON](http://bolinfest.com/essays/json.html) | |||
|  | 
 | |||
|  | [Douglas Crockford](http://www.crockford.com/) of course designed and built | |||
|  | JSON, but his state machine diagrams on the [JSON website](http://json.org/), as | |||
|  | cheesy as it may sound, gave us motivation and confidence that building a new | |||
|  | parser to implement these ideas was within reach! The original | |||
|  | implementation of JSON5 was also modeled directly off of Doug’s open-source | |||
|  | [json_parse.js] parser. We’re grateful for that clean and well-documented | |||
|  | code. | |||
|  | 
 | |||
|  | [json_parse.js]: | |||
|  | https://github.com/douglascrockford/JSON-js/blob/master/json_parse.js | |||
|  | 
 | |||
|  | [Max Nanasy](https://github.com/MaxNanasy) has been an early and prolific | |||
|  | supporter, contributing multiple patches and ideas. | |||
|  | 
 | |||
|  | [Andrew Eisenberg](https://github.com/aeisenberg) contributed the original | |||
|  | `stringify` method. | |||
|  | 
 | |||
|  | [Jordan Tucker](https://github.com/jordanbtucker) has aligned JSON5 more closely | |||
|  | with ES5, wrote the official JSON5 specification, completely rewrote the | |||
|  | codebase from the ground up, and is actively maintaining this project. |