; Tools</nav><h1>Module <code>Tools</code></h1><p>A small set of useful utilities</p><nav class="toc"><ul><li><a href="#printing-stuff">Printing stuff</a></li></ul></nav></header><section><header><h2 id="printing-stuff"><a href="#printing-stuff" class="anchor"></a>Printing stuff</h2></header><dl><dt class="spec value" id="val-fail_fmt"><a href="#val-fail_fmt" class="anchor"></a><code><span class="keyword">val</span> fail_fmt : <span><span>(<span class="type-var">'a</span>, Stdlib.Format.formatter, unit, 