ther <code>T|E</code> implementatation like 
<a href="https://wg21.link/P0323" class="api-reference" target="_blank"><i class="fa fa-book" aria-hidden="true"></i> P0323 <code>std::expected&lt;T, E&gt;</code></a>

&ndash; with custom incommensurate <code>E</code> types, or indeed arbitrary return
types which are &ldquo;split&rdquo; <code>T|E</code> return types. Solving
this well is the <em>coup de gr√¢ce</em> of Outcome against alternative approaches
to this problem domain,
including <code>std::expected&