jinja2.runtime.Undefined¶

class jinja2.runtime.Undefined(hint=None, obj=missing, name=None, exc=<class 'jinja2.exceptions.UndefinedError'>)[source]¶

The default undefined type. This undefined type can be printed and iterated over, but every other access will raise an jinja2.exceptions.UndefinedError:

>>> foo = Undefined(name='foo')
>>> str(foo)
''
>>> not foo
True
>>> foo + 42
Traceback (most recent call last):
  ...
jinja2.exceptions.UndefinedError: 'foo' is undefined