jinja2.runtime.DebugUndefined¶

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

An undefined that returns the debug info when printed.

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