my $data = <<EOT;
This is just lines of text here, and also there.  Consider
this human readable text; it's full of letters and
punctuation.
EOT

my %table = ( '\b[Ll]ines of text\b' => "foo.html",
              '\b[Tt]his\b'          => "bar.html",
              '\b[Ii]t\'?s full\b'   => "foobar.html" );

$data =~ s/($_)/<a href="$table{$_}">$1<\/a>/g foreach keys %table;

print $data;