this smells like premature optimization... 
foreach (@files) {
  process_file $_ if (/foo[34]\.txt$/i or
                      /bar[12]\.txt$/i)
}

[download]
it's easier to read and to maintain, and I am sure you will not notice any speed lost, specially if you are going to access the files after it.

In reply to Re: Regex Tuning by salva
in thread Regex Tuning /(?:(?:foo[34])|(?:bar[12]))\.txt/io by songahji

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