Expand a Bash brace pattern into its full list

Expand Bash brace alternatives and sequences into their generated words.

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ToolBash Brace Expansion
Input
Output
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How it works

Comma alternatives and numeric or alphabetic sequences expand before pathname expansion, producing the Cartesian product of adjacent expressions. Generated words are literal and do not require matching files.

  • Brace expansion is an early textual shell step.
  • Quoting suppresses expansion when literal braces are needed.

Worked example

file{1..3}{a,b}.txt
A numeric range and a comma list, combined
Input
											file{1..3}{a,b}.txt
Output
												Expansions: file1a.txt, file1b.txt, file2a.txt, file2b.txt, file3a.txt, file3b.txt
Count: 6
Warning:

When to use this

Backup loops, build scripts, and mkdir commands generate related paths.

Edge cases

  • file{a,b} expands even when the files do not exist.
  • Nested ranges can create a large Cartesian product.
  • '{a,b}' remains literal because quoting disables expansion.

References