anchor.diff:    line starts with a semicolon, then comes the option name ended by a
     semicolon and after that the option’s value (may be omitted for boolean
     options).
  -  :include: .//section[0]/node()
  -  :exclude: ./div[@class="listingblock"]
  -  :header_footer:
  +  :option-1: value 1
  +  :option-2: value 1
  +  :option-2: value 2
  +  :boolean-option:
   -->
   <div class="colist">
     <ol>
  
positive.code: 
  ----
  
  === HTML
  
  [source, html]
  ----
  
negative.code: 
  ----
  
  
  === Generate examples
  
  Writing examples of an expected output for all the input examples from scratch is quite a chore.
  Therefore DocTest provides a generator, so when you have at least partially working Asciidoctor _backend_ (converter or set of templates), you can pass the input examples through it and generate your output examples.
  Then you should verify them and modify if needed.
  
  Assume that you have defined the generator Rake task named `:generator` (see <<setup-doctest>>).
  
  Now you can generate output examples from all the input examples (those with `.adoc` extension) found on the examples_path that doesn’t already exist (i.e. it doesn’t rewrite existing):
  
  [source, sh]
  bundle exec rake generate
  