title: php array_map with static method of object
body: <p>I want to use <strong>array_map</strong> with a static method but I fail.
  Here is my code : </p>
  
  <pre><code>Class Buy {
  
      public function payAllBills() {
          $bill_list = OtherClass::getBillList();
          return array_map(array(self, 'pay'), $bill_list); // Issue line
      }
  
      private static function pay($bill) {
          // Some stuff
          return true;
      }
  
  }
  </code></pre>
  
  <p>PHP gives me the error : </p>
  
  <pre><code>Use of undefined constant self - assumed 'self'
  </code></pre>
  
  <p>I have also tried : </p>
  
  <pre><code>return array_map('self::makeBean()', $model_list);
  </code></pre>
  
  <p>But it doesn't work.</p>
  
  <p>Do you have any idea how to use array_map with static method ?</p>
  
  <p>I have already read : <a href="https://stackoverflow.com/questions/1077491/can-a-method-be-used-as-a-array-map-function-in-php-5-2">Can a method be used as a array_map function in PHP 5.2?</a> but this question is about standard methods, not statics.</p>