note mdillon how about this: <code>#!/usr/bin/perl -w use strict; use Algorithm::Diff qw(diff LCS); use HTML::TokeParser; use LWP::Simple; sub tokenize_url { my $url = shift; my $content = get $url or die $!; my $p = new HTML::TokeParser(\$content); my (@tokens, $token); push @tokens, $token while (defined ($token = $p->get_token)); \@tokens; } my @content = map { tokenize_url($_) } qw{ http://perlmonks.org/index.pl?node_id=32285 http://perlmonks.org/index.pl?node_id=32286 }; # hash tokens based on their text content sub hash_token {$_[0][$_[0][0] eq 'T' ? 1 : -1]} my @diffs = diff $content[0], $content[1], \&hash_token; my @LCS = LCS $content[0], $content[1], \&hash_token; my $largest = 0; for my $hunk (@diffs) { my (@deletions, @additions); for (@$hunk) { push @deletions, $_ if $_->[0] eq '-'; push @additions, $_ if $_->[0] eq '+'; } my $size = @deletions > @additions ? @deletions : @additions; $largest = $size if $size > $largest; } print scalar(@{$content[0]}), " line", (@{$content[0]} == 1 ? '' : 's'), " in original", $/; print scalar(@{$content[1]}), " line", (@{$content[1]} == 1 ? '' : 's'), " in revision", $/; print scalar(@diffs), " hunk", (@diffs == 1 ? '' : 's'), " differ", $/; print $largest, " line", ($largest == 1 ? '' : 's'), " in largest hunk", $/; printf "Revision %0.2f%% similar to original$/", 100 * @LCS / @{$content[0]}; </code> <p><strong>updated 2001-Aug-01</strong>: small code changes; renamed from "RE: Re: HTML Document Comparison"</p> 32285 32286