rints &quot;[1, 2, 3, -1, -2, 4, 5, 6, -1, -2, 7, 8, 9]&quot;</code></pre>

<p><strong><code>separator</code>:</strong>  A sequence to insert between each of this
  sequence&#39;s elements.
<strong>Returns:</strong> The joined sequence of elements.</p>

    <h4>Declaration</h4>    
    <code class="language-swift">func joined&lt;Separator&gt;(separator: Separator) -&gt; JoinedSequence&lt;LazyDropWhileSequence&lt;Base&gt;&gt; where Separator : Sequence, Separator.Element == LazyDropWhileSequence&lt;Base&gt;.