Skip to main content


Laurence MorganAbout 1 min


Glob pattern matching for file system objects (eg *.txt)


Returns a list of files and directories that match a glob pattern.

Output is a JSON list.


g pattern -> <stdout>

[ <stdin> -> ] @g command pattern [ -> <stdout> ]

!g pattern -> <stdout>

<stdin> -> g pattern -> <stdout>

<stdin> -> !g pattern -> <stdout>


Inline globbing:

cat @{ g *.txt }

Writing a JSON array of files to disk:

g *.txt |> filelist.json

Writing a list of files to disk:

g *.txt -> format str |> filelist.txt

Checking if a file exists:

if { g somefile.txt } then {
    # file exists

Checking if a file does not exist:

!if { g somefile.txt } then {
    # file does not exist

Return all files apart from text files:

!g *.txt

Filtering a file list based on glob matches:

f +f -> g *.md

Remove any glob matches from a file list:

f +f -> !g *.md


Pattern Reference

  • * matches any number of (including zero) characters
  • ? matches any single character

Inverse Matches

If you want to exclude any matches based on wildcards, rather than include them, then you can use the bang prefix. eg

» g READ*

» !g *
Error in `!g` (1,1): No data returned.

When Used As A Method

!g first looks for files that match its pattern, then it reads the file list from STDIN. If STDIN contains contents that are not files then !g might not handle those list items correctly. This shouldn't be an issue with frx in its normal mode because it is only looking for matches however when used as !g any items that are not files will leak through.

This is its designed feature and not a bug. If you wish to remove anything that also isn't a file then you should first pipe into either g *, rx .*, or f +f and then pipe that into !g.

The reason for this behavior is to separate this from !regexp and !match.


  • g
  • !g

See Also

  • f: Lists or filters file system objects (eg files)
  • match: Match an exact value in an array
  • regexp: Regexp tools for arrays / lists of strings
  • rx: Regexp pattern matching for file system objects (eg .*\\.txt)

This document was generated from builtins/core/io/g_doc.yamlopen in new window.

Last update:
Contributors: Laurence Morgan,Laurence,Laurence Morgan