Base class for descriptors whose order in the class body should be preserved. Intended for use in concert with the
OrderedDescriptormust define a value for a class attribute called
_class_attribute_. This is the name of a class attribute on the container class for these descriptors, which will be set to an
OrderedDictat class creation time. This
OrderedDictwill contain a mapping of all class attributes that were assigned instances of the
OrderedDescriptorsubclass, to the instances themselves. See the documentation for
OrderedDescriptorContainerfor a concrete example.
Optionally, subclasses of
OrderedDescriptormay define a value for a class attribute called
_name_attribute_. This should be the name of an attribute on instances of the subclass. When specified, during creation of a class containing these descriptors, the name attribute on each instance will be set to the name of the class attribute it was assigned to on the class.
Although this class is intended for use with descriptors (i.e. classes that define any of the
__delete__magic methods), this base class is not itself a descriptor, and technically this could be used for classes that are not descriptors too. However, use with descriptors is the original intended purpose.