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1[![NPM version](https://img.shields.io/npm/v/esprima.svg)](https://www.npmjs.com/package/esprima)
2[![npm download](https://img.shields.io/npm/dm/esprima.svg)](https://www.npmjs.com/package/esprima)
3[![Build Status](https://img.shields.io/travis/jquery/esprima/master.svg)](https://travis-ci.org/jquery/esprima)
4[![Coverage Status](https://img.shields.io/codecov/c/github/jquery/esprima/master.svg)](https://codecov.io/github/jquery/esprima)
5
6**Esprima** ([esprima.org](http://esprima.org), BSD license) is a high performance,
7standard-compliant [ECMAScript](http://www.ecma-international.org/publications/standards/Ecma-262.htm)
8parser written in ECMAScript (also popularly known as
9[JavaScript](https://en.wikipedia.org/wiki/JavaScript)).
10Esprima is created and maintained by [Ariya Hidayat](https://twitter.com/ariyahidayat),
11with the help of [many contributors](https://github.com/jquery/esprima/contributors).
12
13### Features
14
15- Full support for ECMAScript 2017 ([ECMA-262 8th Edition](http://www.ecma-international.org/publications/standards/Ecma-262.htm))
16- Sensible [syntax tree format](https://github.com/estree/estree/blob/master/es5.md) as standardized by [ESTree project](https://github.com/estree/estree)
17- Experimental support for [JSX](https://facebook.github.io/jsx/), a syntax extension for [React](https://facebook.github.io/react/)
18- Optional tracking of syntax node location (index-based and line-column)
19- [Heavily tested](http://esprima.org/test/ci.html) (~1500 [unit tests](https://github.com/jquery/esprima/tree/master/test/fixtures) with [full code coverage](https://codecov.io/github/jquery/esprima))
20
21### API
22
23Esprima can be used to perform [lexical analysis](https://en.wikipedia.org/wiki/Lexical_analysis) (tokenization) or [syntactic analysis](https://en.wikipedia.org/wiki/Parsing) (parsing) of a JavaScript program.
24
25A simple example on Node.js REPL:
26
27```javascript
28> var esprima = require('esprima');
29> var program = 'const answer = 42';
30
31> esprima.tokenize(program);
32[ { type: 'Keyword', value: 'const' },
33 { type: 'Identifier', value: 'answer' },
34 { type: 'Punctuator', value: '=' },
35 { type: 'Numeric', value: '42' } ]
36
37> esprima.parseScript(program);
38{ type: 'Program',
39 body:
40 [ { type: 'VariableDeclaration',
41 declarations: [Object],
42 kind: 'const' } ],
43 sourceType: 'script' }
44```
45
46For more information, please read the [complete documentation](http://esprima.org/doc).
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