Re: Finding the intersection between two regexes

2014-04-22 Thread David Cantrell
On Sun, Apr 20, 2014 at 10:14:48PM -0400, Mark Fowler wrote: On Sunday, April 20, 2014, David Cantrell da...@cantrell.org.uk wrote: Can anyone point me at some code on the CPAN that, given two regexes, can figure out whether there are any bits of text that will be matched by both? I'm not

Re: Finding the intersection between two regexes

2014-04-22 Thread Paul Makepeace
On Tue, Apr 22, 2014 at 4:16 AM, David Cantrell da...@cantrell.org.uk wrote: On Sun, Apr 20, 2014 at 10:14:48PM -0400, Mark Fowler wrote: On Sunday, April 20, 2014, David Cantrell da...@cantrell.org.uk wrote: Can anyone point me at some code on the CPAN that, given two regexes, can figure

Re: Finding the intersection between two regexes

2014-04-22 Thread Ben Evans
This piece of anecdotal evidence is now a good ~8 years out of date, but I found that there were some surprising performance regressions for a complex, combined regex versus versus multiple runs with simple ones. As ever the moral of the story is, if performance matters, always measure, and get a