class="anchor"></a><code><span><span class="keyword">val</span> matches : <span><span class="label">caller</span>:<a href="#type-t">t</a> <span class="arrow">&#45;&gt;</span></span> <span><span class="label">callee</span>:<a href="#type-t">t</a> <span class="arrow">&#45;&gt;</span></span> bool</span></code></div><div class="spec-doc"><p>Return true if the <code>caller</code> element kind matches the <code>callee</code> element kind. Used during trace expansion; we will only consider expanding the trace from