Hello.

I tried clustering some file names based on their prefix (those beginning with closers) while ignoring the specific numerical values within them.
To achieve this, whenever a desired prefix pattern appeared, I subbed the numerical values with \d++ so it can be used later as a regex pattern,
however since the prefix contains closers and possibly other special regex characters, I have sandwiched all non-\d++ parts with \Q and \E,
but that raises the error Unrecognized escape \Q passed through in regex;
I can't seem to figure what I am missing ?
 ...
 if($fName =~ /^([\[\(].+?[\]\)])/)
  {
    #pref detected. generalizing digits
      my $pref = '^\Q'.$1.'\E';
      $pref =~ s/\d++/\\E\\d++\\Q/g;
    #finding indexes of matches to this prefix
      my @matchIndexes;
      for(my $mex=0;$mex<@fNames;$mex++)
      {if($fNames[$mex] =~ /$pref/i){push(@matchIndexes,$mex);}}
    ...

[download]
Thank you very much for any assistance, and have an awesome day ☺

Update: resolved by quotemeta(), thx to Eily.

In reply to Q regex escape within variable by palkia

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