in the result.
<strong>Returns:</strong> A subsequence of the initial, consecutive elements that
  satisfy <code>predicate</code>.</p>

<p><strong>Complexity:</strong> O(<em>n</em>), where <em>n</em> is the length of the collection.
<strong>See Also:</strong> <code>drop(while:)</code></p>

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