The problem of sorting a file full of nothing but HTML mailto: links came across my desk, and armed with Perl I naturally solved it a few minutes (a miracle for me, this stuff is finally starting to stick). Then I noticed that not all of the links in the file actually contained mailto: even if they were linking to email addresses. So now I'm stuck trying to change my regex to match either the entire word "mailto:" or nothing at all. My best guess is commented below. Can anyone offer me advice? (And yes, I have read Death to Dot Star! even if I don't fully comprehend it yet.) 
#!/usr/bin/perl -w
use strict;

my %names;

while ( <> ) {
    s/\s+/ /ig;
    /<a href="(.*)">(.*)<\/a><br>/;
    # /<a href="(mailto:)??(.*)">(.*)<\/a><br>/;
    $names{"$2($1)"} = $1;
}

open OUT, ">sortboater.txt" or die "Cannot open file: $!";

for ( sort keys %names ) {
    /^(.*)\(.*\)$/;
    print OUT qq(<a href="mailto:$names{$_}">$1</a><br />\n);
}

close OUT or die "Cannot close file: $!";

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In reply to Problems with regex grouping by patgas

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