[Python-checkins] cpython (3.3): Close issue #16267: better docs for @abstractmethod composition
nick.coghlan
python-checkins at python.org
Sat Dec 8 13:57:34 CET 2012
http://hg.python.org/cpython/rev/3345afd6dc61
changeset: 80753:3345afd6dc61
branch: 3.3
parent: 80751:8ba3c975775b
user: Nick Coghlan <ncoghlan at gmail.com>
date: Sat Dec 08 22:56:02 2012 +1000
summary:
Close issue #16267: better docs for @abstractmethod composition
files:
Doc/library/abc.rst | 59 ++++++++++++++++++++++++--------
Misc/NEWS | 3 +
2 files changed, 47 insertions(+), 15 deletions(-)
diff --git a/Doc/library/abc.rst b/Doc/library/abc.rst
--- a/Doc/library/abc.rst
+++ b/Doc/library/abc.rst
@@ -208,16 +208,20 @@
A subclass of the built-in :func:`classmethod`, indicating an abstract
classmethod. Otherwise it is similar to :func:`abstractmethod`.
- Usage::
+ This special case is deprecated, as the :func:`classmethod` decorator
+ is now correctly identified as abstract when applied to an abstract
+ method::
class C(metaclass=ABCMeta):
- @abstractclassmethod
+ @classmethod
+ @abstractmethod
def my_abstract_classmethod(cls, ...):
...
.. versionadded:: 3.2
.. deprecated:: 3.3
- Use :class:`classmethod` with :func:`abstractmethod` instead.
+ It is now possible to use :class:`classmethod` with
+ :func:`abstractmethod`, making this decorator redundant.
.. decorator:: abstractstaticmethod(function)
@@ -225,21 +229,26 @@
A subclass of the built-in :func:`staticmethod`, indicating an abstract
staticmethod. Otherwise it is similar to :func:`abstractmethod`.
- Usage::
+ This special case is deprecated, as the :func:`staticmethod` decorator
+ is now correctly identified as abstract when applied to an abstract
+ method::
class C(metaclass=ABCMeta):
- @abstractstaticmethod
+ @staticmethod
+ @abstractmethod
def my_abstract_staticmethod(...):
...
.. versionadded:: 3.2
.. deprecated:: 3.3
- Use :class:`staticmethod` with :func:`abstractmethod` instead.
+ It is now possible to use :class:`staticmethod` with
+ :func:`abstractmethod`, making this decorator redundant.
.. decorator:: abstractproperty(fget=None, fset=None, fdel=None, doc=None)
- A subclass of the built-in :func:`property`, indicating an abstract property.
+ A subclass of the built-in :func:`property`, indicating an abstract
+ property.
Using this function requires that the class's metaclass is :class:`ABCMeta`
or is derived from it. A class that has a metaclass derived from
@@ -247,23 +256,43 @@
and properties are overridden. The abstract properties can be called using
any of the normal 'super' call mechanisms.
- Usage::
+ This special case is deprecated, as the :func:`property` decorator
+ is now correctly identified as abstract when applied to an abstract
+ method::
class C(metaclass=ABCMeta):
- @abstractproperty
+ @property
+ @abstractmethod
def my_abstract_property(self):
...
- This defines a read-only property; you can also define a read-write abstract
- property using the 'long' form of property declaration::
+ The above example defines a read-only property; you can also define a
+ read-write abstract property by appropriately marking one or more of the
+ underlying methods as abstract::
class C(metaclass=ABCMeta):
- def getx(self): ...
- def setx(self, value): ...
- x = abstractproperty(getx, setx)
+ @property
+ def x(self):
+ ...
+
+ @x.setter
+ @abstractmethod
+ def x(self, val):
+ ...
+
+ If only some components are abstract, only those components need to be
+ updated to create a concrete property in a subclass::
+
+ class D(C):
+ @C.x.setter
+ def x(self, val):
+ ...
+
.. deprecated:: 3.3
- Use :class:`property` with :func:`abstractmethod` instead
+ It is now possible to use :class:`property`, :meth:`property.getter`,
+ :meth:`property.setter` and :meth:`property.deleter` with
+ :func:`abstractmethod`, making this decorator redundant.
.. rubric:: Footnotes
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -322,6 +322,9 @@
Documentation
-------------
+- Issue #16267: Better document the 3.3+ approach to combining
+ @abstractmethod with @staticmethod, @classmethod and @property
+
- Issue #15209: Clarify exception chaining description in exceptions module
documentation
--
Repository URL: http://hg.python.org/cpython
More information about the Python-checkins
mailing list