| # JSON5 – JSON for Humans |
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| [][Build Status] |
| [][Coverage |
| Status] |
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| 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]. |
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| This JavaScript library is the official reference implementation for JSON5 |
| parsing and serialization libraries. |
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| [Build Status]: https://travis-ci.com/json5/json5 |
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| [Coverage Status]: https://coveralls.io/github/json5/json5 |
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| [JSON]: https://tools.ietf.org/html/rfc7159 |
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| [ECMAScript 5.1]: https://www.ecma-international.org/ecma-262/5.1/ |
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| ## 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. |
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| ### Arrays |
| - Arrays may have a single trailing comma. |
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| ### Strings |
| - Strings may be single quoted. |
| - Strings may span multiple lines by escaping new line characters. |
| - Strings may include character escapes. |
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| ### 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. |
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| [IdentifierName]: https://www.ecma-international.org/ecma-262/5.1/#sec-7.6 |
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| [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 implementation 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/03157639c7a7cddd2e9f032537f346f1a87c0f6d/json_parse.js |
| |
| [Max Nanasy](https://github.com/MaxNanasy) has been an early and prolific |
| supporter, contributing multiple patches and ideas. |
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| [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. |