title: Curly Braces Notation in PHP
body: <p>I was reading source of OpenCart and I ran into such expression below. Could someone explain it to me:</p>
  
  <pre><code>$quote = $this-&gt;{'model_shipping_' . $result['code']}-&gt;getQuote($shipping_address);
  </code></pre>
  
  <p>In the statement, there is a weird code part that is<br>
  <code>$this-&gt;{'model_shipping_' . $result['code']}</code><br>
  which has <code>{}</code> and I wonder what that is? It looks an object to me but I am not really sure.</p>