</span> <span><span class="type-var">'b</span> option</span></code></dt><dt class="spec value" id="val-mem_assoc"><a href="#val-mem_assoc" class="anchor"></a><code><span class="keyword">val</span> mem_assoc : <span class="type-var">'a</span> <span>&#45;&gt;</span> <span><span>(<span class="type-var">'a</span> * <span class="type-var">'b</span>)</span> list</span> <span>&#45;&gt;</span> bool</code></dt><dt class="spec value" id="val-mem_assq"><a href="#val-mem_assq" class="anchor"></a><code><span class="keyw