I'd write this as follows:
if message.length
.alert.alert-danger= message
... as message
is a string, message.length
evaluates to a falsy value (0) only if it's an empty string. I've also used buffered output
here (note that =
character) so that message
value will be HTML escaped.
An alternative approach is comparing message
with an empty string directly:
if message !== ''
.alert.alert-danger= message
Note that I dropped div
in div.alert.alert-danger
expression, as it's kind of default element for Jade templates. Have you used any other element, you'd have to start the expression with its tagname.