One thing you could do is precompile the regex and save it in a variable ala
my $regex = qr/.*ST\S+\s*\S*B15--.*[^02468]]/o; my @match_sp = $all_lines =~ /$regex/mg; Note the 'o' option on the qr//, which tells perl to compile the regex only once. I'm not sure if it applies in this case or not, but it's something to check. -----Original Message----- From: Alan Campbell [mailto:[EMAIL PROTECTED] Sent: Friday, May 19, 2006 3:13 PM To: beginners@perl.org Subject: reg exp speed? hello folks, I'm slurping in a large file and seeing a nice speedup versus line by line processing...but I'm losing it in my (likely poorly constructed!) reg-expression match <snip explanation> my @match_sp = $all_lines =~ /.*ST\S+\s*\S*B15--.*[^02468]]/mg; <snip> -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] <http://learn.perl.org/> <http://learn.perl.org/first-response>