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