braces

Fastest brace expansion for node.js, with the most complete support for the Bash 4.3 braces specification.

• Complete support for the braces part of the Bash 4.3 specification. Braces passes all of the relevant unit tests from the spec.
• Expands comma-separated values: a/{b,c}/d => ['a/b/d', 'a/c/d']
• Expands alphabetical or numerical ranges: {1..3} => ['1', '2', '3']
• Very fast
• Special characters can be used to generate interesting patterns.

Install with npm

npm i braces --save

Example usage

var braces = require('braces');

braces('a/{x,y}/c{d}e')
//=> ['a/x/cde', 'a/y/cde']

braces('a/b/c/{x,y}')
//=> ['a/b/c/x', 'a/b/c/y']

braces('a/{x,{1..5},y}/c{d}e')
//=> ['a/x/cde', 'a/1/cde', 'a/y/cde', 'a/2/cde', 'a/3/cde', 'a/4/cde', 'a/5/cde']

Pro tip!

Use braces to generate test fixtures!

Example

var braces = require('./');
var path = require('path');
var fs = require('fs');

braces('blah/{a..z}.js').forEach(function(fp) {
  if (!fs.existsSync(path.dirname(fp))) {
    fs.mkdirSync(path.dirname(fp));
  }
  fs.writeFileSync(fp, '');
});

See the tests for more examples and use cases (also see the bash spec tests);

Range expansion

Uses expand-range for range expansion.

braces('a{1..3}b')
//=> ['a1b', 'a2b', 'a3b']

braces('a{5..8}b')
//=> ['a5b', 'a6b', 'a7b', 'a8b']

braces('a{00..05}b')
//=> ['a00b', 'a01b', 'a02b', 'a03b', 'a04b', 'a05b']

braces('a{01..03}b')
//=> ['a01b', 'a02b', 'a03b']

braces('a{000..005}b')
//=> ['a000b', 'a001b', 'a002b', 'a003b', 'a004b', 'a005b']

braces('a{a..e}b')
//=> ['aab', 'abb', 'acb', 'adb', 'aeb']

braces('a{A..E}b')
//=> ['aAb', 'aBb', 'aCb', 'aDb', 'aEb']

Pass a function as the last argument to customize range expansions:

var range = braces('x{a..e}y', function (str, i) {
  return String.fromCharCode(str) + i;
});

console.log(range);
//=> ['xa0y', 'xb1y', 'xc2y', 'xd3y', 'xe4y']

See expand-range for benchmarks, tests and the full list of range expansion features.

Options

options.makeRe

Type: Boolean

Deafault: false

Return a regex-optimal string. If you're using braces to generate regex, this will result in dramatically faster performance.

Examples

With the default settings ({makeRe: false}):

braces('{1..5}');
//=> ['1', '2', '3', '4', '5']

With {makeRe: true}:

braces('{1..5}', {makeRe: true});
//=> ['[1-5]']

braces('{3..9..3}', {makeRe: true});
//=> ['(3|6|9)']

options.bash

Type: Boolean

Default: false

Enables complete support for the Bash specification. The downside is a 20-25% speed decrease.

Example

Using the default setting ({bash: false}):

braces('a{b}c');
//=> ['abc']

In bash (and minimatch), braces with one item are not expanded. To get the same result with braces, set {bash: true}:

braces('a{b}c', {bash: true});
//=> ['a{b}c']

options.nodupes

Type: Boolean

Deafault: true

Duplicates are removed by default. To keep duplicates, pass {nodupes: false} on the options

Bash 4.3 Support

Better support for Bash 4.3 than minimatch

This project has comprehensive unit tests, including tests coverted from Bash 4.3. Currently only 8 of 102 unit tests fail, and

Run benchmarks

Install dev dependencies:

npm i -d && npm benchmark

#1: escape.js
  brace-expansion.js x 114,934 ops/sec ±1.24% (93 runs sampled)
  braces.js x 342,254 ops/sec ±0.84% (90 runs sampled)

#2: exponent.js
  brace-expansion.js x 12,359 ops/sec ±0.86% (96 runs sampled)
  braces.js x 20,389 ops/sec ±0.71% (97 runs sampled)

#3: multiple.js
  brace-expansion.js x 114,469 ops/sec ±1.44% (94 runs sampled)
  braces.js x 401,621 ops/sec ±0.87% (91 runs sampled)

#4: nested.js
  brace-expansion.js x 102,769 ops/sec ±1.55% (92 runs sampled)
  braces.js x 314,088 ops/sec ±0.71% (98 runs sampled)

#5: normal.js
  brace-expansion.js x 157,577 ops/sec ±1.65% (91 runs sampled)
  braces.js x 1,115,950 ops/sec ±0.74% (94 runs sampled)

#6: range.js
  brace-expansion.js x 138,822 ops/sec ±1.71% (91 runs sampled)
  braces.js x 1,108,353 ops/sec ±0.85% (94 runs sampled)

Run tests

Install dev dependencies:

npm i -d && npm test

Related

• micromatch: wildcard/glob matcher for javascript. a faster alternative to minimatch.
• fill-range: Fill in a range of numbers or letters, optionally passing an increment or multiplier to use
• expand-range: Wraps fill-range for fast, bash-like range expansion in strings. Expand a range of numbers or letters, uppercase or lowercase

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Please run benchmarks before and after any code changes to what the impact of the code changes are before submitting a PR.

Author

Jon Schlinkert

• github/jonschlinkert
• twitter/jonschlinkert

License

Copyright (c) 2014-2015 Jon Schlinkert
Released under the MIT license

This file was generated by verb-cli on March 18, 2015.