preheat_open.query.NoElementError

exception preheat_open.query.NoElementError

Exception raised when no elements are found in a generator.

This exception is raised by the unique() function when attempting to retrieve a unique element from a generator that yields no elements.

Example:

>>> def empty_generator():
...     return
...     yield  # This line is never reached
>>>
>>> try:
...     unique(empty_generator())
... except NoElementError as e:
...     str(e)
'Generator yields no elements'