l></nav><div class="odoc-content"><div class="odoc-spec"><div class="spec type anchored" id="type-key"><a href="#type-key" class="anchor"></a><code><span><span class="keyword">type</span> key</span><span> = string</span></code></div></div><div class="odoc-spec"><div class="spec type anchored" id="type-compare_key"><a href="#type-compare_key" class="anchor"></a><code><span><span class="keyword">type</span> compare_key</span></code></div></div><div class="odoc-spec"><div class="spec type anchored" id="type-t"