title: Declaring php class member variables
body: <p>I was trying to write a class in such simple way</p>
  
  <pre><code>class piklu
  {
     private $x=5;
     public function display()
     {
        echo $this-&gt;$x;
     }
  }
  </code></pre>
  
  <p>but when after creating object of this class I'm calling the function display it is displaying an error unkown variable $x. Can any body suggest me what exactly I have to do to declare a private member variable in php.</p>