https://github.com/pugjs/is-expression

Validates a string as a JavaScript expression
https://github.com/pugjs/is-expression

Last synced: 6 days ago
JSON representation

Validates a string as a JavaScript expression

• Host: GitHub
• URL: https://github.com/pugjs/is-expression
• Owner: pugjs
• License: mit
• Created: 2015-11-12T01:31:44.000Z (about 9 years ago)
• Default Branch: master
• Last Pushed: 2024-08-16T10:00:34.000Z (6 months ago)
• Last Synced: 2025-01-19T11:12:41.850Z (13 days ago)
• Language: JavaScript
• Homepage:
• Size: 44.9 KB
• Stars: 9
• Watchers: 3
• Forks: 10
• Open Issues: 7
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE.md
  • Security: SECURITY.md

Awesome Lists containing this project

README

        
# is-expression

Validates a string as a JavaScript expression

[![Build Status](https://img.shields.io/github/workflow/status/pugjs/is-expression/Test/master)](https://github.com/pugjs/is-expression/actions?query=branch%3Amaster+workflow%3ATest)

[![Dependency Status](https://img.shields.io/david/pugjs/is-expression.svg)](https://david-dm.org/pugjs/is-expression)

[![Rolling Versions](https://img.shields.io/badge/Rolling%20Versions-Enabled-brightgreen)](https://rollingversions.com/pugjs/is-expression)

[![npm version](https://img.shields.io/npm/v/is-expression.svg)](https://www.npmjs.org/package/is-expression)

## Installation

    npm install is-expression

## Usage

### `isExpression(src[, options])`

Validates a string as a JavaScript expression.

`src` contains the source.

`options` can contain any Acorn options (since we use Acorn under-the-hood),

or any of the following:

- `throw`: Throw an error if the string is not an expression. The error can

  be an Acorn error, with location information in `err.loc` and `err.pos`.

  Defaults to `false`.

- `strict`: Use strict mode when trying to parse the string. Defaults to

  `false`. Even if this option is `false`, if you have provided

  `options.sourceType === 'module'` which imples strict mode under ES2015,

  strict mode will be used.

- `lineComment`: When `true`, allows line comments in the expression.

  Defaults to `false` for safety.

See the examples below for usage.

## Examples

```js

var isExpression = require('is-expression')

isExpression('myVar')

//=> true

isExpression('var')

//=> false

isExpression('["an", "array", "\'s"].indexOf("index")')

//=> true

isExpression('var', {throw: true})

// SyntaxError: Unexpected token (1:0)

//     at Parser.pp.raise (acorn/dist/acorn.js:940:13)

//     at ...

isExpression('public')

//=> true

isExpression('public', {strict: true})

//=> false

isExpression('abc // my comment')

//=> false

isExpression('abc // my comment', {lineComment: true})

//=> true

```

## License

MIT