edgegraph.structure.singleton.drop_semi_singleton_mapping

edgegraph.structure.singleton.drop_semi_singleton_mapping#

edgegraph.structure.singleton.drop_semi_singleton_mapping(cls, *args, **kwargs)#

Remove an mapping from the specified semi-singleton instance.

This removes a single mapping of a key to instance. It may be considered removing a semisingleton instance, though if multiple mappings exist to single instance, it will still be accessible by other remaining identifiers.

See also

>>> from edgegraph.singleton import semi_singleton_metaclass, \
        drop_semi_singleton_mapping
>>> class SemiSingleton(metaclass=semi_singleton_metaclass()):
...     def __init__(self, foo, bar=False):
...         self.foo = foo
...         self.bar = bar
...
>>> s3 = SemiSingleton(37, True)  # different arguments -- different object
>>> s3
<__main__.SemiSingleton object at 0x01234567>
>>> s4 = SemiSingleton(4)
>>> s5 = SemiSingleton(5)
>>> drop_semi_singleton_mapping(SemiSingleton, 4)  # drop s4
>>> s4_2 = SemiSingleton(4)  # will now return a new instance
>>> s4 is s4_2
False
>>> SemiSingleton(5) is s5  # other mappings unaffected
True
Parameters:

  • cls (type) – Class to remove the mapping from. This is typically thought of as type(some_object).

  • *args – Positional arguments as would normally be passed to the semi-singleton class instantiation.

  • **kwargs – Positional arguments as would normally be passed to the semi-singleton class instantiation.