@stuff = split m{
        <!--end-->
        <a \s name=" ( \d+ ) "></a>
        <!--start-->
        }x => $data;

##</code><code>##

while( $data =~ m{ \G
            <a \s+ href = " (\d+) "></a>
            <!--start-->
            ( .+? )
            <!--end-->
        }xg ){
    my $number = $1;
    my $data   = $2;
    #...
}