anchor.diff:  
   This is *not bold
   
  -because we do not cross* paragraph boundaries.
  +because we do not cross* paragraph boundaries in our implementation.
   
   This is *also bold** despite the second asterisk at the end.
   
  
positive.code:   'DocBook - The Definitive Guide'. O'Reilly & Associates.
    1999. ISBN 1-56592-580-7.
  
  Three square brackets make a bibliography anchor. (I'm getting a false positive on the ``1999'' in the previous paragraph, as if it were a numbered list. But I don't care!)
  
  A footnote footnote:[An example footnote.]. It is just a form of macro. I don't use them.
  // Note to self: use them. (By the way, this is a comment.)
  
  I do use ((indexes)), though.(((index term)))
  
  
negative.code: 
  This _is italic_ and this is_n't_. But this (_is_). This is __too_ because the second is inside.
  
  _An italic line._
  
  This *is bold* and this is*n't*. But this (,*is*). This is **too* because the second is inside.
  
  *A bold line.*
  
  This is _italic containing *bold* text_, while this is *bold text containing _italic_ text*.
  
  +A literal line.+
  
  This +is literal+ and this is+n't+.
  
  This is +literal #containing# *bold* text+ and this is +literal containing _italic_ text+.
  