edicate</code>:</strong>  A closure that takes an element of the sequence as
  its argument and returns a Boolean value indicating whether the
  element is a match.
<strong>Returns:</strong> The first element of the sequence that satisfies <code>predicate</code>,
  or <code>nil</code> if there is no element that satisfies <code>predicate</code>.</p>

    <h4>Declaration</h4>    
    <code class="language-swift">func first(where predicate: (LazyFilterSequence&lt;Base&gt;.Iterator.Element) throws -&gt; Bool) 