ref="value.html" title="Struct value">value</a> <span class="special">:</span> <span class="keyword"></span> <a class="link" href="../callable.html" title="Struct callable">proto::callable</a> <span class="special">{</span>
  <span class="comment">// member classes/structs/unions</span>
  <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> This<span class="special">,</span> <span class="keyword">typename</span> <a class="link" href="../../../Expr.html"