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1# balanced-match
2
3Match balanced string pairs, like `{` and `}` or `<b>` and `</b>`. Supports regular expressions as well!
4
5[![build status](https://secure.travis-ci.org/juliangruber/balanced-match.svg)](http://travis-ci.org/juliangruber/balanced-match)
6[![downloads](https://img.shields.io/npm/dm/balanced-match.svg)](https://www.npmjs.org/package/balanced-match)
7
8[![testling badge](https://ci.testling.com/juliangruber/balanced-match.png)](https://ci.testling.com/juliangruber/balanced-match)
9
10## Example
11
12Get the first matching pair of braces:
13
14```js
15var balanced = require('balanced-match');
16
17console.log(balanced('{', '}', 'pre{in{nested}}post'));
18console.log(balanced('{', '}', 'pre{first}between{second}post'));
19console.log(balanced(/\s+\{\s+/, /\s+\}\s+/, 'pre  {   in{nest}   }  post'));
20```
21
22The matches are:
23
24```bash
25$ node example.js
26{ start: 3, end: 14, pre: 'pre', body: 'in{nested}', post: 'post' }
27{ start: 3,
28  end: 9,
29  pre: 'pre',
30  body: 'first',
31  post: 'between{second}post' }
32{ start: 3, end: 17, pre: 'pre', body: 'in{nest}', post: 'post' }
33```
34
35## API
36
37### var m = balanced(a, b, str)
38
39For the first non-nested matching pair of `a` and `b` in `str`, return an
40object with those keys:
41
42* **start** the index of the first match of `a`
43* **end** the index of the matching `b`
44* **pre** the preamble, `a` and `b` not included
45* **body** the match, `a` and `b` not included
46* **post** the postscript, `a` and `b` not included
47
48If there's no match, `undefined` will be returned.
49
50If the `str` contains more `a` than `b` / there are unmatched pairs, the first match that was closed will be used. For example, `{{a}` will match `['{', 'a', '']` and `{a}}` will match `['', 'a', '}']`.
51
52### var r = balanced.range(a, b, str)
53
54For the first non-nested matching pair of `a` and `b` in `str`, return an
55array with indexes: `[ <a index>, <b index> ]`.
56
57If there's no match, `undefined` will be returned.
58
59If the `str` contains more `a` than `b` / there are unmatched pairs, the first match that was closed will be used. For example, `{{a}` will match `[ 1, 3 ]` and `{a}}` will match `[0, 2]`.
60
61## Installation
62
63With [npm](https://npmjs.org) do:
64
65```bash
66npm install balanced-match
67```
68
69## Security contact information
70
71To report a security vulnerability, please use the
72[Tidelift security contact](https://tidelift.com/security).
73Tidelift will coordinate the fix and disclosure.
74
75## License
76
77(MIT)
78
79Copyright (c) 2013 Julian Gruber &lt;julian@juliangruber.com&gt;
80
81Permission is hereby granted, free of charge, to any person obtaining a copy of
82this software and associated documentation files (the "Software"), to deal in
83the Software without restriction, including without limitation the rights to
84use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
85of the Software, and to permit persons to whom the Software is furnished to do
86so, subject to the following conditions:
87
88The above copyright notice and this permission notice shall be included in all
89copies or substantial portions of the Software.
90
91THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
92IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
93FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
94AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
95LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
96OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
97SOFTWARE.
98