edgegraph.structure.singleton.get_all_semi_singleton_instances

edgegraph.structure.singleton.get_all_semi_singleton_instances(cls)

Get all instances belonging to a given semi-singleton type.

This is a simple operation, in concept: it retrieves all the unique instances of the specified semi-singleton type. It may best be explained by example:

>>> from edgegraph.structure import singleton
>>> class SemiSingle(metaclass=singleton.semi_singleton_metaclass()): pass
>>> instances = [SemiSingle(i) for i in range(10)]  # all unique instances
>>> checked = singleton.get_all_semi_singleton_instances(SemiSingle)
>>> set(checked) == set(instances)  # use sets -- order may not be same
True

Note

Internally, references to these instances are kept as the value side of a dictionary, which maintains insertion order. Therefore, some semblence of order may be present, but it shouldn’t be relied upon.

See also

• semi_singleton_metaclass(), for more info about semi-singletons

• clear_semi_singleton(), to reset a given semi-singleton

Parameters:

cls (type) – Data type to check singleton instances for.

Returns:

Generator expression yielding semi-singleton instances.

Return type:

Generator[object]