title: Problem with optional arguments in PHP
body: <p>I have a function which takes four optional arguments:</p>
  
  <pre><code>public function doSomething($x = null, $y = null, $a = null, $b = null) {  }
  </code></pre>
  
  <p>However when I try to call this function and specify only $y for instance:</p>
  
  <pre><code>$object-&gt;doSomething($y=3)
  </code></pre>
  
  <p>It seems to ignore that I am setting $y as 3, and instead sets $x to be 3. Is there any reason why this might happen with PHP? I never used to have this issue before...</p>
  
  <p>Thanks,</p>
  
  <p>Dan</p>