="keyword">val</span> identity : <span><span class="type-var">'a</span> <a href="../argument-1-I/index.html#type-t">I.t</a></span> <span>&#45;&gt;</span> bool</code></dt><dt class="spec value" id="val-composition"><a href="#val-composition" class="anchor"></a><code><span class="keyword">val</span> composition : <span>(<span class="type-var">'a</span> <span>&#45;&gt;</span> <span class="type-var">'b</span>)</span> <span>&#45;&gt;</span> <span>(<span class="type-var">'b</span> <span>&#45;&gt;</span> <span cla