sub toc {
    my $source = shift;

    my @parsed;
    my $h_flag;
    my $data;

    my $text_sub = sub {
        if ($h_flag) {
            $data->{text} = shift;
            push @parsed, $data;
            $data   = undef;
            $h_flag = 0;
        }
    };

    ## my $end_sub = sub {
    ##   if ($h_flag) {
    ##     $data   = undef;
    ##     $h_flag = 0;
    ##   }
    ## };

    my $tag_sub = sub {
        my $s    = shift;
        my $tag  = shift;
        my $self = shift;

        if ( $tag =~ m/[hH](\d)/ ) {
            $data   = { level => $1, tag => $tag, text => "" };
            $h_flag = 1;
        }
    };

    # HTML-Parser erzeugen
    my $p = HTML::Parser->new(
        api_version => 3,
        start_h     => [ $tag_sub, "text,tagname,self" ],
        #end_h       => [ $end_sub,  "text,tagname,self" ],
        text_h => [ $text_sub, "text,self" ],
        #process_h     => [ $text_sub, "text,self" ],
        #comment_h     => [ $text_sub, "text,self" ],
        #declaration_h => [ $text_sub, "text,self" ],
        #default_h     => [ $text_sub, "text,self" ],
    );
    $p->empty_element_tags(1);
    $p->report_tags(qw(h1 h2 h3 h4 h5 h6));
    $p->xml_pic(1);
    $p->utf8_mode(1);
    $p->case_sensitive(1);
    $p->parse($source);
    $p->eof();

    return @parsed;

} ## end sub toc