mirror of https://github.com/jab/bidict.git
54 lines
1.4 KiB
ReStructuredText
54 lines
1.4 KiB
ReStructuredText
.. _other-bidict-types:
|
|
|
|
Other bidict Types
|
|
==================
|
|
|
|
Now that we've covered
|
|
:class:`bidict.bidict`,
|
|
:class:`bidict.collapsingbidict`,
|
|
and some other basics,
|
|
let's look at the remaining bidict types
|
|
and the hierarchy they belong to.
|
|
|
|
bidict Type Hierarchy
|
|
---------------------
|
|
|
|
.. image:: _static/bidict_types.png
|
|
:alt: bidict type hierarchy
|
|
|
|
At the top of the bidict type hierarchy is
|
|
:class:`bidict.BidirectionalMapping`.
|
|
This implements the :class:`collections.abc.Mapping` ABC
|
|
and contains the shared logic allowing keys to be looked up by value
|
|
(as well as values to be looked up by key).
|
|
Most users will only ever need to use one of its subclasses.
|
|
|
|
At this point the type hierarchy tree forks into
|
|
a mutable branch and an immutable branch.
|
|
On the mutable side we have
|
|
:class:`bidict.bidict`
|
|
(which implements :class:`collections.abc.MutableMapping`)
|
|
and finally
|
|
:class:`bidict.collapsingbidict`,
|
|
the leaf on this side of the tree.
|
|
|
|
Polymorphism
|
|
++++++++++++
|
|
|
|
Note that none of the bidict types inherit from dict.
|
|
The following example demonstrates a recommended way to verify
|
|
that a bidict is dict-like::
|
|
|
|
>>> from collections import Mapping
|
|
>>> from bidict import bidict
|
|
>>> b = bidict()
|
|
>>> isinstance(b, Mapping)
|
|
True
|
|
|
|
.. include:: frozenbidict.rst.inc
|
|
|
|
.. include:: namedbidict.rst.inc
|
|
|
|
There's one last useful bit of functionality to mention:
|
|
:ref:`the "inverted" iterator <inverted>`.
|