braces

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

Install

Install with npm:

$ npm install braces --save

Features

• Complete support for the braces part of the Bash 4.3 Brace Expansion. 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.

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']

Use case: fixtures

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

Latest results

#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)

Related projects

You might also be interested in these projects:

• expand-range: Fast, bash-like range expansion. Expand a range of numbers or letters, uppercase or lowercase. See… more | homepage
• fill-range: Fill in a range of numbers or letters, optionally passing an increment or multiplier to… more | homepage
• micromatch: Glob matching for javascript/node.js. A drop-in replacement and faster alternative to minimatch and multimatch. | homepage

Contributing

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

Building docs

Generate readme and API documentation with verb:

$ npm install verb && npm run docs

Or, if verb is installed globally:

$ verb

Running tests

Install dev dependencies:

$ npm install -d && npm test

Author

Jon Schlinkert

• github/jonschlinkert
• twitter/jonschlinkert

License

Copyright © 2016, Jon Schlinkert. Released under the MIT license.

This file was generated by verb, v0.9.0, on May 21, 2016.