work.suroh.tk/node_modules/is-expression/README.md

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2019-12-02 12:22:45 +00:00
# is-expression
Validates a string as a JavaScript expression
[![Build Status](https://img.shields.io/travis/pugjs/is-expression/master.svg)](https://travis-ci.org/pugjs/is-expression)
[![Dependency Status](https://img.shields.io/david/pugjs/is-expression.svg)](https://david-dm.org/pugjs/is-expression)
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## 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