E = varies&gt;</code></a>

and <a href="../../../reference/aliases/checked.html" class="api-reference"><code>checked&lt;T, E = varies&gt;</code></a>
 (both of which are type aliases hard coding no-value
policies <a href="../../../tutorial/essential/no-value/builtin.html">as previously covered in this tutorial</a>).</p>

<p>Expected and Outcome are <a href="../../../faq.html#why-doesn-t-outcome-duplicate-std-expected-t-e-s-design">isomorphic to one another in design intent</a>, but interoperation
for code us