in reply to Self-Shrinking Character Classes

...or, for a less subtle, more brute-force method:
@words = qw (perl lerp lepp wombat); $pattern = ".e.."; @pattern_elements = split "", $pattern; word: foreach $word (@words) { my @bag = qw (p r l); # Reset bag my @letters = split "", $word; print "\nTesting $word...\n"; for my $i(0...$#letters) { my $element = $pattern_elements[$i]; # Create a character class with the letter bag my $class = '['.join ("", @bag).']'; if ($letters[$i] =~ m/($class)/) { # If matched, remove the letter from the bag @bag = grep /[^$1]/, @bag; } elsif ($letters[$i] eq $element) { next; } else { print "$word not matched\n"; next word; } } print "$word matched!\n" if @bag == 0; }
yields:
Testing perl... perl matched! Testing lerp... lerp matched! Testing lepp... lepp not matched Testing wombat... wombat not matched
Not sure how efficient it is, or even how robust it is, but heck, it looks like it does what you want. It tracks each letter in your search string against each character in a search pattern, makes a match (if possible) and shrinks the bag by the match. Hope this helps.

Gary Blackburn
Trained Killer