title: php function calls with and without brackets
body: <p>When using relationships in laravel it is possible to call a relationship function with or without brackets:</p>
  
  <pre><code>public function posts()
  {
    return $this-&gt;hasMany('Post');
  }
  
  $user-&gt;posts();
  $user-&gt;posts;
  </code></pre>
  
  <p>The first call will return an instance of the query builder and the second call will return an array of all the posts.</p>
  
  <p>How is this feature made?</p>