I don't see what's so wrong with your code but you could also grep it. Something like (untested): 
my @result = map { process_file($_) } grep (/(?:foo[34]|bar[12])\.txt/
+i, @files);

[download]

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

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