on</span></code></dt><dt class="spec value" id="val-filter"><a href="#val-filter" class="anchor"></a><code><span class="keyword">val</span> filter : <span>(<span class="type-var">'a</span> <span>&#45;&gt;</span> bool)</span> <span>&#45;&gt;</span> <span><span class="type-var">'a</span> list</span> <span>&#45;&gt;</span> <span><span class="type-var">'a</span> list</span></code></dt><dt class="spec value" id="val-find_all"><a href="#val-find_all" class="anchor"></a><code><span class="keyword">val</span> find_