anchor.diff:  6. A pool declaration, which looks like +pool _poolname_+. Pools are explained
      <<ref_pool, in the section on pools>>.
   
  +[[ref_lexer]]
   Lexical syntax
   ~~~~~~~~~~~~~~
   
  
positive.code: 
  5. Variables from the file that included that file using the
     `subninja` keyword.
  
negative.code:   the command as it's running.  The `-v` flag controls whether to print
    the full command or its description; if a command fails, the full command
    line will always be printed before the command's output.
  
  `dyndep`:: _(Available since Ninja 1.10.)_ Used only on build statements.
    If present, must name one of the build statement inputs.  Dynamically
    discovered dependency information will be loaded from the file.
    See the <<ref_dyndep,dynamic dependencies>> section for details.
  
  `generator`:: if present, specifies that this rule is used to
    re-invoke the generator program.  Files built using `generator`
  