al</span> all : <span><span><span>(<span class="type-var">'io</span>, <span class="type-var">'io</span>, <span class="type-var">'err</span>)</span> <a href="index.html#type-validator">validator</a></span> list</span> <span>&#45;&gt;</span> <span><span>(<span class="type-var">'io</span>, <span class="type-var">'io</span>, <span class="type-var">'err</span>)</span> <a href="index.html#type-validator">validator</a></span></code></dt><dd><p>Validate a value using a list of validators. This runs all the vali