perlquestion Eyck <p>Hi, I find myself writting another app this month that requires matching against list of patterns, what I did the last time is: <code> #... while ($line=<>) { #... foreach $user (keys(%$users)) { my $pattern=$user->{'Pattern'}; if ($line=~/$pattern/i) { print STDERR "Great, we found pattern $pattern!\n"; } }; }; </code> <p> This is straitghtforwad and it works. <p>The problem is that it grows roughly <tt>N**2</tt>, (because there is relation between number of lines to parse, and amount of possible patterns). <p>UPDATE: I keep patterns in hashref because the whole point of this excercise is to figure out WHICH regexp matched. ORing patterns together might be fine if I knew how to figure out which patter from such ORed pattern matched exactly. <p> What do people do with such problems? Is it possible to optimise this? ( for example, group patterns into eee...groups based on common prefix or something common, or maybe preprocess those lines, split sentences into functional parts .. ) <p> This seems like rather common task, are there any smart (or at least working) solutions?