specifies how a parser 
  is embedded in a composite. By default, if one is not specified, the parser 
  will be embedded by value. That is, a copy of the parser is placed as a member 
  variable of the composite. Most parsers are embedded by value. In certain situations 
  however, this is not desirable or possible. One particular example is the <a href="rule.html">rule</a>. 
  The rule, unlike other parsers is embedded by reference.</p>
<h2><a name="match"></a>The match</h2>
<p>The match holds the result 