|&gt; q in
let v =
  try
    let _ = P.parse_string p &quot;&quot; in
    false
  with
  | _ -&gt; true
in
v = true</code></pre></div></div><div class="odoc-spec"><div class="spec value" id="val-let*" class="anchored"><a href="#val-let*" class="anchor"></a><code><span><span class="keyword">val</span> let* : <span><span><span class="type-var">'a</span> <a href="#type-t">t</a></span> <span class="arrow">&#45;&gt;</span></span> <span><span>(<span><span class="type-var">'a</span> <span class="arrow">&#45;&gt;</