It's not possible to combine those regexps if those are trully meant to be captures ((...)) and not groupings ((?:...)). At least, it wouldn't be possible without change the variables in which the data is captured.

Let's assume that you only used the parens for grouping (and that you forgot $ at the end of each regexp), then you'd be starting with the following: 

if ($file =~ /^\d{8}(?:_\d+)*\.ilf$/i ||
    $file =~ /^\d{8}(?:\s\d+)*\.sht$/i
) {
   ...
}

[download]

The possibilities for joining are still quite limited since there is a mixture of common and not common elements. The following illustrates this: 

      vvvvvvvvv  vvv vvv   vvvv  common
     /^\d{8}(?:_ \d+)*\.ilf$/ix
     /^\d{8}(?:\s\d+)*\.sht$/ix
               ^^       ^^^      not common

[download]

The best that can be done, as far as I can tell, is to join the common beginning and the common ending. The following illustrates this: 

            (?:_ \d+)*\.ilf
     /^\d{8}               $/ix
            (?:\s\d+)*\.sht

[download]

We get the following regexp: 

if ($file =~ /^\d{8}(?:(?:_\d+)*\.ilf|(?:\s\d+)*\.sht)$/i) {
   ...
}

[download]

This is definitely less readable.

In reply to Re: File name regex by ikegami
in thread File name regex by dev2dev

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