https://github.com/goto-bus-stop/is-es-version
check if some source code uses syntax supported by an ES version
https://github.com/goto-bus-stop/is-es-version
Last synced: 3 months ago
JSON representation
check if some source code uses syntax supported by an ES version
- Host: GitHub
- URL: https://github.com/goto-bus-stop/is-es-version
- Owner: goto-bus-stop
- License: other
- Created: 2018-02-14T10:19:15.000Z (over 7 years ago)
- Default Branch: master
- Last Pushed: 2024-03-11T14:03:21.000Z (over 1 year ago)
- Last Synced: 2024-04-14T07:46:20.416Z (about 1 year ago)
- Language: JavaScript
- Size: 8.79 KB
- Stars: 6
- Watchers: 2
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE.md
Awesome Lists containing this project
README
# is-es-version
check if some source code uses syntax supported by an ES version
You can use this before eg. running Babel with a million transforms on a file. Note that this attempts to parse the file using [acorn](https://github.com/acornjs/acorn), so it is pretty slow; recommended to memoize the result!
[![npm][npm-image]][npm-url]
[![travis][travis-image]][travis-url]
[![standard][standard-image]][standard-url]
[npm-image]: https://img.shields.io/npm/v/is-es-version.svg?style=flat-square
[npm-url]: https://www.npmjs.com/package/is-es-version
[travis-image]: https://img.shields.io/travis/goto-bus-stop/is-es-version.svg?style=flat-square
[travis-url]: https://travis-ci.org/goto-bus-stop/is-es-version
[standard-image]: https://img.shields.io/badge/code%20style-standard-brightgreen.svg?style=flat-square
[standard-url]: http://npm.im/standard
## Install
```
npm install is-es-version
```
## Usage
```js
var isEsVersion = require('is-es-version')
isEsVersion('const a = 10', 5) // false
isEsVersion('var a = 10', 5) // true
```
## API
### `isEsVersion(src, version=5, opts={})`
Check if `src` is a source code string that is supported by the EcmaScript version `version`. The default version is 5. Returns true if the syntax is supported by the given version; false if not.
Set `opts.parser` to use a custom parser module, such as [acorn-node](https://github.com/browserify/acorn-node).
```js
isEsVersion('#!/usr/bin/env node\nrequire("./lib/cli")', 5, { parser: require('acorn-node') })
```
## License
[Apache-2.0](LICENSE.md)