title: Is it possible to pass NULL as argument in ${...} expression?
body: <p>I am working with Spring and Thymeleaf.
  I need to remove one parameter from current url and I am doing something like this in view:</p>
  
  <pre><code>urlBuilder=${T(org.springframework.web.servlet.support.ServletUriComponentsBuilder).fromCurrentRequest()},
  currentUrl=${urlBuilder.replaceQueryParam('page',null).build()
  </code></pre>
  
  <p>However, that <code>null</code> value is not null actually. If I debug that line, value of that parameter is not null but an empty object, here is the screenshot:</p>
  
  <p><a href="https://i.stack.imgur.com/qApUE.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qApUE.png" alt="enter image description here"></a></p>
  
  <p>Is there any way to pass real <code>null</code> from SpEL? </p>
  
  <p>Behavior of builder component is slightly different in both cases, as when you pass null, then query param will be removed. In given example, query param stays on the URL.</p>