use strict;
my $str = '<h1>This is a large heading</h1>
<p>This is a sample content paragraph.</p>
<h2 style="somestyle">This header line</h2>
<p>This is another content paragraph.</p>
<h2>Another header line</h2>';
my $regex = qr/<h\d{1}(?:.*?)>(?<title>.*?)<\/h\d{1}>/p;
my $subst = '';
my $result = $str =~ s/$regex/$subst/rg;
print "The result of the substitution is' $result\n";
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html