Expression resolves to unused I Value
<p>I am new to Swift and I am trying to change background colour of button.</p>

<p>I am using <code>chicken1</code> to change the background colour of the button all together</p>

<p>But I keep getting this error</p>

<blockquote>
  <p>Expression resolves to unused I Value"</p>
</blockquote>

<p>Here is the current code.</p>

<pre><code>let chicken1 = button1; button2
chicken1.backgroundColor = UIColor.blueColor()
</code></pre>

<p>Also should I use 'var' insted?</p>