ion">K</span> <span class="parameter-name">key</span>, </span> <span class="parameter" id="putIfAbsent-param-ifAbsent"><span class="type-annotation">V</span> <span class="parameter-name">ifAbsent</span>()</span>)
    </section>
    
    <section class="summary source-code" id="source">
      <h2><span>Implementation</span> </h2>
      <pre class="language-dart"><code class="language-dart">V putIfAbsent(K key, V ifAbsent()) {
  if (key == null) throw new ArgumentError(key);
  int comp = _splay(key);
  if (co