There's no need to actually use it in the eval, and you can save off the result and use it after the check. 

sub validate_re {
  my $re = shift;
  eval { $re = qr/$re/ };
  return $@ ? undef : $re
}

[download]

That will return either an already compiled regexp or undef (and $@ will indicate what was wrong in that case).

In reply to Re^2: Test RegEx Validity by Fletch
in thread Test RegEx Validity by aplonis

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