lved">Stdlib</span>.Format.formatter, unit, <span class="type-var">_</span> )</span> <a href="../../IStdlib/IStd/index.html#type-format4">IStdlib.IStd.format4</a></span> <span class="arrow">&#45;&gt;</span></span>
  <span class="type-var">'a</span></span></code></div><div class="spec-doc"><p>Raise the corresponding exception.</p></div></div><div class="odoc-spec"><div class="spec value" id="val-raise_error" class="anchored"><a href="#val-raise_error" class="anchor"></a><code><span><span class="keyword">val<