n class="special">(</span><span class="identifier">Expr</span><span class="special">)</span><span class="special">&gt;</span> <span class="special">{</span>
  <span class="comment">// types</span>
  <span class="keyword">typedef</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <a name="boost.proto.by_value_generator.result_This(Ex_idp89415056.type"></a><span class="identifier">type</span><span class="special">;</span>
<span class="special">}</span><span class="specia