What is the equivalent of "none" in django templates?

Question

None, False and True all are available within template tags and filters. None, False, the empty string ('', "", """""") and empty lists/tuples all evaluate to False when evaluated by if, so you can easily do

{% if profile.user.first_name == None %}
{% if not profile.user.first_name %}

A hint: @fabiocerqueira is right, leave logic to models, limit templates to be the only presentation layer and calculate stuff like that in you model. An example:

# someapp/models.py
class UserProfile(models.Model):
    user = models.OneToOneField('auth.User')
    # other fields

    def get_full_name(self):
        if not self.user.first_name:
            return
        return ' '.join([self.user.first_name, self.user.last_name])

# template
{{ user.get_profile.get_full_name }}

Hope this helps :)

You can also use another built-in template default_if_none

{{ profile.user.first_name|default_if_none:"--" }}

You can also use the built-in template filter default:

If value evaluates to False (e.g. None, an empty string, 0, False); the default "--" is displayed.

{{ profile.user.first_name|default:"--" }}

Documentation: https://docs.djangoproject.com/en/dev/ref/templates/builtins/#default

isoperator : New in Django 1.10

{% if somevar is None %}
  This appears if somevar is None, or if somevar is not found in the context.
{% endif %}

Look at the yesno helper

Eg:

{{ myValue|yesno:"itwasTrue,itWasFalse,itWasNone" }}