8

I want to process a bunch of files ending in some suffixes, so I wrote the following zsh script but it did not work.

EXT=(.jpg .png .gif)
EXT=${(j.|.)EXT}    # EXT becomes '.jpg|.png|.gif'
for f in *($EXT); do     # should become '*(.jpg|.png|.gif)' but failed
    process-one-file $f
done

Why doesn't it work? How can I mix parameter substitution and glob pattern?

Yuxiao Zeng
  • 83

1 Answers1

10

It does not work because in zsh, globbing is not done by default upon variable expansion. That why in zsh you can do:

rm -- $file

While in other shells, you need:

rm -- "$file"

If you do want globbing, you need to ask for it explicitly as in:

rm -- $~file_pattern

In your case:

for f (*($~EXT)) process-one-file $f

(note that by convention, we tend to use uppercase variable names for environment variables)

Stéphane Chazelas
  • 544,893