">Parser</span></code></a>.
                </p></dd>
</dl>
</div>
<h6>
<a name="spirit.qi.reference.directive.hold.h4"></a>
            <span class="phrase"><a name="spirit.qi.reference.directive.hold.expression_semantics"></a></span><a class="link" href="hold.html#spirit.qi.reference.directive.hold.expression_semantics">Expression
            Semantics</a>
          </h6>
<p>
            Semantics of an expression is defined only where it differs from, or
            is not defined in <a class="link" href