/div>
<div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;<span class="keyword">    </span>{</div>
<div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;        <span class="keywordflow">return</span> std::nullopt;</div>
<div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;    }</div>
<div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160; </div>
<div class="line"><a name="l00091"></a><span class="lineno">   91