Brace expansion, as known from sh/bash, in JavaScript.
import { expand } from 'brace-expansion' expand('file-{a,b,c}.jpg') // => ['file-a.jpg', 'file-b.jpg', 'file-c.jpg'] expand('-v{,,}') // => ['-v', '-v', '-v'] expand('file{0..2}.jpg') // => ['file0.jpg', 'file1.jpg', 'file2.jpg'] expand('file-{a..c}.jpg') // => ['file-a.jpg', 'file-b.jpg', 'file-c.jpg'] expand('file{2..0}.jpg') // => ['file2.jpg', 'file1.jpg', 'file0.jpg'] expand('file{0..4..2}.jpg') // => ['file0.jpg', 'file2.jpg', 'file4.jpg'] expand('file-{a..e..2}.jpg') // => ['file-a.jpg', 'file-c.jpg', 'file-e.jpg'] expand('file{00..10..5}.jpg') // => ['file00.jpg', 'file05.jpg', 'file10.jpg'] expand('{{A..C},{a..c}}') // => ['A', 'B', 'C', 'a', 'b', 'c'] expand('ppp{,config,oe{,conf}}') // => ['ppp', 'pppconfig', 'pppoe', 'pppoeconf']
import { expand } from 'brace-expansion'
Return an array of all possible and valid expansions of str. If none are found, [str] is returned.
The options object can provide a max value to cap the number of expansions allowed. This is limited to 100_000 by default, to prevent DoS attacks.
const expansions = expand('{1..100}'.repeat(5), { max: 100, }) // expansions.length will be 100, not 100^5
The options object can also provide a maxLength value to cap the total number of characters across all expansions. This is limited to 4_000_000 by default, to prevent memory exhaustion from inputs whose result count stays under max while each result grows very long.
const expansions = expand('{a,b}'.repeat(1500), { maxLength: 10_000, })
Valid expansions are:
;/^(.*,)+(.+)?$/ // {a,b,...}
A comma separated list of options, like {a,b} or {a,{b,c}} or {,a,}.
;/^-?\d+\.\.-?\d+(\.\.-?\d+)?$/ // {x..y[..incr]}
A numeric sequence from x to y inclusive, with optional increment. If x or y start with a leading 0, all the numbers will be padded to have equal length. Negative numbers and backwards iteration work too.
;/^-?\d+\.\.-?\d+(\.\.-?\d+)?$/ // {x..y[..incr]}
An alphabetic sequence from x to y inclusive, with optional increment. x and y must be exactly one character, and if given, incr must be a number.
For compatibility reasons, the string ${ is not eligible for brace expansion.