rr</span>)</span> <a href="index.html#type-validator">validator</a></span> <span>&#45;&gt;</span> <span><span>(<span class="type-var">'i</span>, <span class="type-var">'mid</span>, <span class="type-var">'err</span>)</span> <a href="index.html#type-validator">validator</a></span> <span>&#45;&gt;</span> <span><span>(<span class="type-var">'i</span>, <span class="type-var">'o</span>, <span class="type-var">'err</span>)</span> <a href="index.html#type-validator">validator</a></span></code></dt><dd><p>Compo