jinja2.runtime.StrictUndefined

An undefined that barks on print and iteration as well as boolean tests and all kinds of comparisons. In other words: you can do nothing with it except checking if it's defined using the `defined` test. >>> foo = StrictUndefined(name='foo') >>> str(foo) Traceback (most recent call last): ... jinja2.exceptions.UndefinedError: 'foo' is undefined >>> not foo Traceback (most recent call last): ... jinja2.exceptions.UndefinedError: 'foo' is undefined >>> foo + 42 Traceback (most recent call last): ... jinja2.exceptions.UndefinedError: 'foo' is undefined