/span> <span class="type-var">'s</span> <span>&#45;&gt;</span> <span><span>(<span class="type-var">'s</span>, <span class="type-var">'a</span>)</span> <a href="index.html#type-accum">accum</a></span></code></dt></dl><div class="spec module" id="module-State_Left"><a href="#module-State_Left" class="anchor"></a><code><span class="keyword">module</span> <a href="State_Left/index.html">State_Left</a> : <span class="keyword">functor</span> (<a href="State_Left/argument-1-Type/index.html">Type</a> : <a href="..