title: Error parsing thymeleaf template with "1 < 0"
body: <p>Maybe is a stupid question but I failed to retrieve information from Google.
  As the title say, I get a stack trace if a try to parse this simple line:</p>
  
  <pre><code>&lt;span th:if="${1 &lt; 0}"&gt;
  </code></pre>
  
  <p>The error is:</p>
  
  <p><code>org.xml.sax.SAXParseException; lineNumber: 14; columnNumber: 43; The value of attribute "th:if" associated with an element type "null" must not contain the '&lt;' character.</code></p>
  
  <p>But if i try this:</p>
  
  <pre><code>&lt;span th:if="${0 &gt; 1}"&gt;
  </code></pre>
  
  <p>Everything is fine, my question is: Why I get this error?</p>
  
  <p>I believe is related to my lack of experience with Java and thymeleaf, but I don't get why by just changing the position of the elements it work as I expect (return always false).</p>
  
  <p>It is a bug in the parsing of the expression (as checking if 1 is lower than 0 is forbidden by some parser rule) or is just a weird XML parsing issue?</p>
  
  <p>Thank you to all who will even just read.</p>