meteor - meteor 0.8.3 in a template how to check if a data property is not defined ?

Question

In my attempt to update my app to meteor 0.8.3 i have one problem. In some templates i want to check if a "price" property exist (or any other property), and i used to do like this:

{{#if not price}}

it worked in previous version of meteor, but with 0.8.3 i have that error :

Exception in queued task: Error: No such function: not
at http : / / myapp.com/packages/blaze.js?309c2a3b573dca998c07c493ba4953d451b2c963:2494:15
....

I don't see anything about this in meteor documentation. What am i doign wrong ? Thanks

Answer 1

尝试unless：

{{#unless price}}
  ...
{{/unless}}

这应该检查undefined以及其他虚假值。