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,
 7  standard-compliant [ECMAScript](http://www.ecma-international.org/publications/standards/Ecma-262.htm)
 8  parser written in ECMAScript (also popularly known as
 9  [JavaScript](https://en.wikipedia.org/wiki/JavaScript)).
10  Esprima is created and maintained by [Ariya Hidayat](https://twitter.com/ariyahidayat),
11  with 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  
23  Esprima 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  
25  A 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  
46  For more information, please read the [complete documentation](http://esprima.org/doc).