ype.html">ObserveMethodType</a></div><div class="line"><a name="l00046"></a><span class="lineno">   46</span>&#160;     {</div><div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;         <span class="comment">/*identify the variable type from the parent class. */</span></div><div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;         <span class="keyword">using</span> VariableType = decltype(ObserveMethodType::type_indicator_);</div><div class="line"><a 