n><span class="optlabel">?captured_data</span>:<a href="#type-captured_data">captured_data</a> <span class="arrow">&#45;&gt;</span></span>
  <span><span class="optlabel">?is_weak</span>:bool <span class="arrow">&#45;&gt;</span></span>
  <span><a href="../Typ/Name/index.html#type-t">Typ.Name.t</a> <span class="arrow">&#45;&gt;</span></span>
  <span>string <span class="arrow">&#45;&gt;</span></span>
  <a href="#type-t">t</a></span></code></div><div class="spec-doc"><p>create a field of the given class and fie