mirror of
https://github.com/actions/setup-python.git
synced 2024-11-27 03:15:23 +01:00
234 lines
7.5 KiB
Markdown
234 lines
7.5 KiB
Markdown
# JSON5 – JSON for Humans
|
||
|
||
[![Build Status](https://travis-ci.org/json5/json5.svg)][Build Status]
|
||
[![Coverage
|
||
Status](https://coveralls.io/repos/github/json5/json5/badge.svg)][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.
|