an class="type-var">'a</span></span> ]</span> * <span><span class="type-var">'a</span> <a href="#type-t">t</a></span></span></code></div><div class="spec-doc"><p>Find the value bound to the given key if there is one, or otherwise add a binding for the given key with value <code>f ()</code>.</p></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-pop_min_binding"><a href="#val-pop_min_binding" class="anchor"></a><code><span><span class="keyword">val</span> pop_min_binding : <span><span