ode>on_some option</code> is <code>attr</code> if <code>option</code> is <code>Some attr</code> and <code>empty</code> if <code>option</code> is <code>None</code>.</p></div></div><div class="odoc-spec"><div class="spec value anchored" id="val-on_ok"><a href="#val-on_ok" class="anchor"></a><code><span><span class="keyword">val</span> on_ok : <span><span><span>(<a href="#type-t">t</a>, <span class="type-var">'e</span>)</span> <span class="xref-unresolved">Stdlib</span>.result</span> <span class="arrow">&#45;&