in reply to Performance of assambled regex

Hi Foodeywo

I would discourage using /o modifier, because of this note in perlre for v5.22:

  o  - pretend to optimize your code, but actually introduce bugs

using qr// is much better practice, as you can control when the compilation happens. If you want to know exactly how perl handles your regexps you can use:

perl -Mre=debug -d -ne 'print if (/MYLARGEREGEX_HERE/../END_OF_BLOCK/)' inputfile > outputfile

-Mre=debug gives you nice output about regex compilation and matching
and
-d puts you into debugger.

Go through your program step by step with "s" debugger option.

Happy hacking,
natan

---- PS: my first post on PerlMonks. Hello everybody!