#?Copyright?2007?Google?Inc.?All?Rights?Reserved.
#?Licensed?to?PSF?under?a?Contributor?Agreement.

“““Abstract?base?Classes?（ABCs）?according?to?PEP?3119.“““

import?types

from?_weakrefset?import?WeakSet

#?Instance?of?old-style?class
class?_C:?pass
_InstanceType?=?type（_C（））


def?abstractmethod（funcobj）:
????“““A?decorator?indicating?abstract?methods.

????Requires?that?the?metaclass?is?ABCmeta?or?derived?from?it.??A
????class?that?has?a?metaclass?derived?from?ABCmeta?cannot?be
????instantiated?unless?all?of?its?abstract?methods?are?overridden.
????The?abstract?methods?can?be?called?using?any?of?the?normal
????‘super‘?call?mechanisms.

????Usage:

????????class?C:
????????????__metaclass__?=?ABCmeta
????????????@abstractmethod
????????????def?my_abstract_method（self?...）:
????????????????...
????“““
????funcobj.__isabstractmethod__?=?True
????return?funcobj


class?abstractproperty（property）:
????“““A?decorator?indicating?abstract?properties.

????Requires?that?the?metaclass?is?ABCmeta?or?derived?from?it.??A
????class?that?has?a?metaclass?derived?from?ABCmeta?cannot?be
????instantiated?unless?all?of?its?abstract?properties?are?overridden.
????The?abstract?properties?can?be?called?using?any?of?the?normal
????‘super‘?call?mechanisms.

????Usage:

????????class?C:
????????????__metaclass__?=?ABCmeta
????????????@abstractproperty
????????????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:

????????class?C:
????????????__metaclass__?=?ABCmeta
????????????def?getx（self）:?...
????????????def?setx（self?value）:?...
????????????x?=?abstractproperty（getx?setx）
????“““
????__isabstractmethod__?=?True


class?ABCmeta（type）:

????“““metaclass?for?defining?Abstract?base?Classes?（ABCs）.

????Use?this?metaclass?to?create?an?ABC.??An?ABC?can?be?subclassed
????directly?and?then?acts?as?a?mix-in?class.??You?can?also?register
????unrelated?concrete?classes?（even?built-in?classes）?and?unrelated
????ABCs?as?‘virtual?subclasses‘?--?these?and?their?descendants?will
????be?considered?subclasses?of?the?registering?ABC?by?the?built-in
????issubclass（）?function?but?the?registering?ABC?won‘t?show?up?in
????their?MRO?（Method?Resolution?Order）?nor?will?method
????implementations?defined?by?the?registering?ABC?be?callable?（not
????even?via?super（））.

????“““

????#?A?global?counter?that?is?incremented?each?time?a?class?is
????#?registered?as?a?virtual?subclass?of?anything.??It?forces?the
????#?negative?cache?to?be?cleared?before?its?next?use.
????_abc_invalidation_counter?=?0

????def?__new__（mcls?name?bases?namespace）:
????????cls?=?super（ABCmeta?mcls）.__new__（mcls?name?bases?namespace）
????????#?Compute?set?of?abstract?method?names
????????abstracts?=?set（name
?????????????????????for?name?value?in?namespace.items（）
?????????????????????if?getattr（value?“__isabstractmethod__“?False））
????????for?base?in?bases:
????

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件??????242139??2011-02-27?03:00??plugins\doc\Pythonscript\Pythonscript.chm
?????文件??????914432??2011-02-27?03:00??plugins\Pythonscript.dll
?????文件????????7145??2010-12-12?00:07??plugins\Pythonscript\lib\abc.py
?????文件???????33246??2009-10-15?01:30??plugins\Pythonscript\lib\aifc.py
?????文件??????????60??2008-10-15?19:49??plugins\Pythonscript\lib\antigravity.py
?????文件????????2620??2002-06-01?22:18??plugins\Pythonscript\lib\anydbm.py
?????文件???????87304??2010-12-12?00:07??plugins\Pythonscript\lib\argparse.py
?????文件???????11840??2009-01-13?19:52??plugins\Pythonscript\lib\ast.py
?????文件???????11402??2008-09-09?08:49??plugins\Pythonscript\lib\asynchat.py
?????文件???????20612??2010-12-12?00:07??plugins\Pythonscript\lib\asyncore.py
?????文件????????1705??2006-11-17?00:50??plugins\Pythonscript\lib\atexit.py
?????文件????????7597??2008-05-07?07:23??plugins\Pythonscript\lib\audiodev.py
?????文件???????11357??2010-12-12?00:07??plugins\Pythonscript\lib\base64.py
?????文件???????22344??2010-02-22?18:55??plugins\Pythonscript\lib\baseHTTPServer.py
?????文件????????5744??2008-05-10?10:27??plugins\Pythonscript\lib\Bastion.py
?????文件???????20967??2010-12-12?00:07??plugins\Pythonscript\lib\bdb.py
?????文件???????14476??2010-05-06?03:09??plugins\Pythonscript\lib\binhex.py
?????文件????????2595??2009-04-01?01:47??plugins\Pythonscript\lib\bisect.py
?????文件????????2730??2008-07-23?19:38??plugins\Pythonscript\lib\bsddb\db.py
?????文件???????11344??2010-03-22?22:22??plugins\Pythonscript\lib\bsddb\dbobj.py
?????文件????????5308??2006-06-11?16:35??plugins\Pythonscript\lib\bsddb\dbrecio.py
?????文件???????12204??2010-03-22?22:22??plugins\Pythonscript\lib\bsddb\dbshelve.py
?????文件???????30879??2010-11-07?19:12??plugins\Pythonscript\lib\bsddb\dbtables.py
?????文件????????2964??2009-10-15?02:01??plugins\Pythonscript\lib\bsddb\dbutils.py
?????文件???????15988??2010-04-04?00:06??plugins\Pythonscript\lib\bsddb\__init__.py
?????文件??????212480??2011-02-06?23:58??plugins\Pythonscript\lib\bz2.pyd
?????文件???????23107??2010-12-12?00:07??plugins\Pythonscript\lib\calendar.py
?????文件???????34478??2010-12-12?00:07??plugins\Pythonscript\lib\cgi.py
?????文件???????12986??2010-12-12?00:07??plugins\Pythonscript\lib\CGIHTTPServer.py
?????文件???????12073??2010-04-02?02:17??plugins\Pythonscript\lib\cgitb.py
?????文件????????5372??2006-02-19?05:10??plugins\Pythonscript\lib\chunk.py
............此處省略626個文件信息