title: Coldfusion syntax - how to use Evaluate
body: <p>I'm trying to determine if a variable with a variable name is defined. Please help with my syntax... my attempts so far:</p>
  
  <pre><code>&lt;cfif isDefined(Evaluate("session['#url.sessionSQL#']['SQL_ALL']"))&gt;
  
  &lt;cfif isDefined('Evaluate("session[#url.sessionSQL#]")["SQL_ALL"]')&gt;
  
  &lt;cfif isDefined(Evaluate("session['#url.sessionSQL#']['SQL_ALL']"))&gt;        
  
  &lt;cfif isDefined('session[Evaluate("#url.sessionSQL#")]["SQL_ALL"]')&gt;
  
  &lt;cfif isDefined('session["#url.sessionSQL#"]["SQL_ALL"]')&gt;
  </code></pre>
  
  <p>Thanks.</p>