Actually, it didn't. I don't see how to incorporate that into the following. print_definitions will not be the only subroutine that I may want to parse from within the __DATA__ of a document which is being parsed by print_story.

The very first line is confusing with the two hyphens you put after the shebang. I looked at Safe, and don't understand what the big deal is, since all blocks to me are separate compartments of code to begin with. I take it that $str is equivalent to __DATA__ in your example. I have no idea what my $namespace = __PACKAGE__; is doing. I see you created a dispatch table, but it appears empty of anything that looks like what I'm trying to do.

print_story is the subroutine I've used the most throughout my site. You've latched onto print_definitions when in the future there could be print_table, print_list, print_monster, print_books, and more. I'd like to put them in __DATA__ when I want to include them within the body of my text.

sub print_story {
  my ($source,$html) = @_;
  my $tab = $html ? 3 : 4;

  start_html() if $html;
  while (my $line = <$source>) {
    chomp($line);
    if ($line =~ m/^&/) {
      # This is where the code would go to parse the subroutines
      # within __DATA__. The subroutines to be parsed would be 
      # preceded with an &.
    }
    elsif ($line =~ m/^</) {
      line($tab,$line);
    }
    elsif ($line =~ /^[1-6]\s/) {
      my ($heading,$text) = split(/ /,$line,2);
      line($tab,qq(<h$heading>$text</h$heading>));
    }
    else {
      line($tab,qq(<p>$line</p>));
    }
  }
  line($tab,qq(<p class="author">written by $user</p>)) if $tab == 3;
  end_html if $html;
}
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If you could point me to a few perldocs to explain some of what you did and how to incorporate it into print_story I'd be grateful.