def add_slide_directive_before_h1( content )

  # mark h1 for getting wrapped into slide divs
  # note: use just <h1 since some processors add ids e.g. <h1 id='x'>

  slide_count = 0

  content = content.gsub( /<h1/ ) do |match|
    slide_count += 1
    "\n<!-- _S9SLIDE_ -->\n#{Regexp.last_match(0)}"
  end
  
  puts "  Adding #{slide_count} slide breaks (using h1 rule)..."
  
  content
end
def add_slide_directive_before_h1( content )

  # mark h1 for getting wrapped into slide divs
  # note: use just <h1 since some processors add ids e.g. <h1 id='x'>

  slide_count = 0

  content = content.gsub( /<h1/ ) do |match|
    slide_count += 1
    "\n<!-- _S9SLIDE_ -->\n#{Regexp.last_match(0)}"
  end
  
  puts "  Adding #{slide_count} slide breaks (using h1 rule)..."
  
  content
end
note/todo: more alternatives/options for slide breaks

  add a simple slide break rule for two or more blank lines
 add slide directive before h1 (tells slideshow gem where to break slides)

 e.g. changes:
 <h1 id='optional' class='optional'>
  to
  html comment -> _S9SLIDE_ (note: rdoc can't handle html comments?)
 <h1 id='optional' class='optional'>