title: express and jade, ignore render errors
body: <p>So, express+jade == cool.  No question there.  However, coming from django, i'm missing the failure mode that the django templates used.  In django, if I try to render a variable that doesn't exist, it just ignores it and moves on.  While there are times this is REALLY annoying, most of the time it is not.  As such, when I try to render a variable in jade with express, express complains with a 500 error if that variable doesn't exist/is undefined.</p>
  
  <pre><code>
  500 TypeError: Jade:14 
  12. ' // main content, post, login, etc ' 
  13. ' - if (data.session.user) ' 
  14. ' != partial(\'dash') ' 
  
  Jade:3 
  1. '- if (data.session.user)' 
  2. ' p #{data.session.user.id}' 
  3. ' p #{data.cookie.connect.sid}' Cannot read property 'connect' of undefined
  </code></pre>
  
  <p>I'm just experimenting here, so ignore what i'm trying to print. :)  In summary, is there an easy way to tell jade/express to ignore errors in the template and continue rendering, such as is the behavior in the django template system.</p>