express node.js pug

Jade – Template Engine: How to check if a variable exists

I’m currently using Jade on a new project. I want to render a page and check if a certain variable is available.


app.get('/register', function(req, res){
res.render('register', {
locals: {
title: 'Register',
text: 'Register as a user.',


- if (username)
p= username
- else
p No Username!

I always get the following error:

username is not defined

Any ideas on how I can fix this?

This should work:

- if (typeof(username) !== 'undefined'){
//-do something