title: Thymeleaf: Can I use messages inside expressions
body: <p>I am using Thymeleaf 3 within a Spring Boot application.
  Currently I am in a situation where I want to use a message expression inside an EL expression (Spring EL).</p>
  
  <p>First use case: trim the message</p>
  
  <pre><code>data:title="${#{message.key}.trim()}
  </code></pre>
  
  <p>Second use case: conditionally create an attribute with a message as its value</p>
  
  <pre><code>data:title="${condition ? #{message.key} : ''}
  </code></pre>
  
  <p>Both examples will produce a syntax error, because <code>#{</code> is not an allowed start of an expression.</p>
  
  <p>Any ideas how to achieve what I want?</p>