on class="desc markdown">
      <p>Returns true if the collection contains an element equal to <code>element</code>.</p>
<p>This operation will check each element in order for being equal to
<code>element</code>, unless it has a more efficient way to find an element
equal to <code>element</code>.</p>
<p>The equality used to determine whether <code>element</code> is equal to an element of
the iterable defaults to the <a href="dart-core/Object/operator_equals.html">Object.==</a> of the element.</p>
<p>Some ty