<span class="xref-unresolved">F</span>.formatter <span class="arrow">&#45;&gt;</span></span> <span><span class="type-var">'a</span> <span class="arrow">&#45;&gt;</span></span> unit)</span> <span class="arrow">&#45;&gt;</span></span>
  <span><span class="label">f</span>:<span>(<span>unit <span class="arrow">&#45;&gt;</span></span> <span class="type-var">'a</span>)</span> <span class="arrow">&#45;&gt;</span></span>
  <span><span><span>(<span class="type-var">'b</span>, <span class="xref-unresolved">F</span>.f