, <span class="type-var">'err</span>)</span> <a href="index.html#type-validator_result">validator_result</a></span> <span>&#45;&gt;</span> <span><span>(<span class="type-var">'whole</span>, <span class="type-var">'err</span>)</span> <a href="index.html#type-validator_result">validator_result</a></span></code></dt><dd><p>Validate a structure as a whole.</p><p>Sometimes we need to validate a property in relation to another.</p><p>This is just a function that takes the output and return a result.</p><pre><co