n> <span class="arrow">&#45;&gt;</span></span> unit</span></code></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-filter_map_inplace"><a href="#val-filter_map_inplace" class="anchor"></a><code><span><span class="keyword">val</span> filter_map_inplace : <span><span>(<span><a href="#type-key">key</a> <span class="arrow">&#45;&gt;</span></span> <span><span class="type-var">'a</span> <span class="arrow">&#45;&gt;</span></span> <span><span class="type-var">'a</span> option</span>)</spa