use Time::HiRes 'time'; # So time() gives a high-resolution value. $TimesToDo = 1000; # Simple setup $TestString = "abababdedfg" x 1000; # Makes a huge string $Count = $TimesToDo; $StartTime = time(); while ($Count-- > 0) { $TestString =~ m/^(a|b|c|d|e|f|g)+$/; } $EndTime = time(); printf("Alternation takes %.3f seconds.\n", $EndTime - $StartTime); $Count = $TimesToDo; $StartTime = time(); while ($Count-- > 0) { $TestString =~ m/^[a-g]+$/; } $EndTime = time(); printf("Character class takes %.3f seconds.\n", $EndTime - $StartTime); ----------------------------------------------------------------------------- Copyright 1997-2024 Jeffrey Friedl