cpython/Doc/library/functools.rst

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:mod:`functools` --- Higher-order functions and operations on callable objects
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==============================================================================
.. module:: functools
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:synopsis: Higher-order functions and operations on callable objects.
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.. moduleauthor:: Peter Harris <scav@blueyonder.co.uk>
.. moduleauthor:: Raymond Hettinger <python@rcn.com>
.. moduleauthor:: Nick Coghlan <ncoghlan@gmail.com>
.. moduleauthor:: Łukasz Langa <lukasz@langa.pl>
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.. sectionauthor:: Peter Harris <scav@blueyonder.co.uk>
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**Source code:** :source:`Lib/functools.py`
--------------
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The :mod:`functools` module is for higher-order functions: functions that act on
or return other functions. In general, any callable object can be treated as a
function for the purposes of this module.
Merge the trunk changes in. Breaks socket.ssl for now. Merged revisions 57392-57619 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r57395 | georg.brandl | 2007-08-24 19:23:23 +0200 (Fri, 24 Aug 2007) | 2 lines Bug #1011: fix rfc822.Message.getheader docs. ........ r57397 | georg.brandl | 2007-08-24 19:38:49 +0200 (Fri, 24 Aug 2007) | 2 lines Patch #1006: port test_winreg to unittest. ........ r57398 | georg.brandl | 2007-08-24 19:46:54 +0200 (Fri, 24 Aug 2007) | 2 lines Fix #1012: wrong URL to :mod:`site` in install/index.rst. ........ r57399 | georg.brandl | 2007-08-24 20:07:52 +0200 (Fri, 24 Aug 2007) | 2 lines Patch #1008: port test_signal to unittest. ........ r57400 | georg.brandl | 2007-08-24 20:22:54 +0200 (Fri, 24 Aug 2007) | 2 lines Port test_frozen to unittest. ........ r57401 | georg.brandl | 2007-08-24 20:27:43 +0200 (Fri, 24 Aug 2007) | 2 lines Document new utility functions in test_support. ........ r57402 | georg.brandl | 2007-08-24 20:30:06 +0200 (Fri, 24 Aug 2007) | 2 lines Remove test_rgbimg output file, there is no test_rgbimg.py. ........ r57403 | georg.brandl | 2007-08-24 20:35:27 +0200 (Fri, 24 Aug 2007) | 2 lines Remove output file for test_ossaudiodev, also properly close the dsp object. ........ r57404 | georg.brandl | 2007-08-24 20:46:27 +0200 (Fri, 24 Aug 2007) | 2 lines Convert test_linuxaudiodev to unittest. Fix a wrong finally clause in test_ossaudiodev. ........ r57406 | collin.winter | 2007-08-24 21:13:58 +0200 (Fri, 24 Aug 2007) | 1 line Convert test_pkg to use unittest. ........ r57408 | georg.brandl | 2007-08-24 21:22:34 +0200 (Fri, 24 Aug 2007) | 2 lines Catch the correct errors. ........ r57409 | georg.brandl | 2007-08-24 21:33:53 +0200 (Fri, 24 Aug 2007) | 2 lines Port test_class to unittest. Patch #1671298. ........ r57415 | collin.winter | 2007-08-24 23:09:42 +0200 (Fri, 24 Aug 2007) | 1 line Make test_structmembers pass when run with regrtests's -R flag. ........ r57455 | nick.coghlan | 2007-08-25 06:32:07 +0200 (Sat, 25 Aug 2007) | 1 line Revert misguided attempt at fixing incompatibility between -m and -i switches (better fix coming soon) ........ r57456 | nick.coghlan | 2007-08-25 06:35:54 +0200 (Sat, 25 Aug 2007) | 1 line Revert compile.c changes that shouldn't have been included in previous checkin ........ r57461 | nick.coghlan | 2007-08-25 12:50:41 +0200 (Sat, 25 Aug 2007) | 1 line Fix bug 1764407 - the -i switch now does the right thing when using the -m switch ........ r57464 | guido.van.rossum | 2007-08-25 17:08:43 +0200 (Sat, 25 Aug 2007) | 4 lines Server-side SSL and certificate validation, by Bill Janssen. While cleaning up Bill's C style, I may have cleaned up some code he didn't touch as well (in _ssl.c). ........ r57465 | neal.norwitz | 2007-08-25 18:41:36 +0200 (Sat, 25 Aug 2007) | 3 lines Try to get this to build with Visual Studio by moving all the variable declarations to the beginning of a scope. ........ r57466 | neal.norwitz | 2007-08-25 18:54:38 +0200 (Sat, 25 Aug 2007) | 1 line Fix test so it is skipped properly if there is no SSL support. ........ r57467 | neal.norwitz | 2007-08-25 18:58:09 +0200 (Sat, 25 Aug 2007) | 2 lines Fix a few more variables to try to get this to compile with Visual Studio. ........ r57473 | neal.norwitz | 2007-08-25 19:25:17 +0200 (Sat, 25 Aug 2007) | 1 line Try to get this test to pass for systems that do not have SO_REUSEPORT ........ r57482 | gregory.p.smith | 2007-08-26 02:26:00 +0200 (Sun, 26 Aug 2007) | 7 lines keep setup.py from listing unneeded hash modules (_md5, _sha*) as missing when they were not built because _hashlib with openssl provided their functionality instead. don't build bsddb185 if bsddb was built. ........ r57483 | neal.norwitz | 2007-08-26 03:08:16 +0200 (Sun, 26 Aug 2007) | 1 line Fix typo in docstring (missing c in reacquire) ........ r57484 | neal.norwitz | 2007-08-26 03:42:03 +0200 (Sun, 26 Aug 2007) | 2 lines Spell check (also americanify behaviour, it's almost 3 times as common) ........ r57503 | neal.norwitz | 2007-08-26 08:29:57 +0200 (Sun, 26 Aug 2007) | 4 lines Reap children before the test starts so hopefully SocketServer won't find any old children left around which causes an exception in collect_children() and the test to fail. ........ r57510 | neal.norwitz | 2007-08-26 20:50:39 +0200 (Sun, 26 Aug 2007) | 1 line Fail gracefully if the cert files cannot be created ........ r57513 | guido.van.rossum | 2007-08-26 21:35:09 +0200 (Sun, 26 Aug 2007) | 4 lines Bill Janssen wrote: Here's a patch which makes test_ssl a better player in the buildbots environment. I deep-ended on "try-except-else" clauses. ........ r57518 | neal.norwitz | 2007-08-26 23:40:16 +0200 (Sun, 26 Aug 2007) | 1 line Get the test passing by commenting out some writes (should they be removed?) ........ r57522 | neal.norwitz | 2007-08-27 00:16:23 +0200 (Mon, 27 Aug 2007) | 3 lines Catch IOError for when the device file doesn't exist or the user doesn't have permission to write to the device. ........ r57524 | neal.norwitz | 2007-08-27 00:20:03 +0200 (Mon, 27 Aug 2007) | 5 lines Another patch from Bill Janssen that: 1) Fixes the bug that two class names are initial-lower-case. 2) Replaces the poll waiting for the server to become ready with a threading.Event signal. ........ r57536 | neal.norwitz | 2007-08-27 02:58:33 +0200 (Mon, 27 Aug 2007) | 1 line Stop using string.join (from the module) to ease upgrade to py3k ........ r57537 | neal.norwitz | 2007-08-27 03:03:18 +0200 (Mon, 27 Aug 2007) | 1 line Make a utility function for handling (printing) an error ........ r57538 | neal.norwitz | 2007-08-27 03:15:33 +0200 (Mon, 27 Aug 2007) | 4 lines If we can't create a certificate, print a warning, but don't fail the test. Modified patch from what Bill Janssen sent on python-3000. ........ r57539 | facundo.batista | 2007-08-27 03:15:34 +0200 (Mon, 27 Aug 2007) | 7 lines Ignore test failures caused by 'resource temporarily unavailable' exceptions raised in the test server thread, since SimpleXMLRPCServer does not gracefully handle them. Changed number of requests handled by tests server thread to one (was 2) because no tests require more than one request. [GSoC - Alan McIntyre] ........ r57561 | guido.van.rossum | 2007-08-27 19:19:42 +0200 (Mon, 27 Aug 2007) | 8 lines > Regardless, building a fixed test certificate and checking it in sounds like > the better option. Then the openssl command in the test code can be turned > into a comment describing how the test data was pregenerated. Here's a patch that does that. Bill ........ r57568 | guido.van.rossum | 2007-08-27 20:42:23 +0200 (Mon, 27 Aug 2007) | 26 lines > Some of the code sets the error string in this directly before > returning NULL, and other pieces of the code call PySSL_SetError, > which creates the error string. I think some of the places which set > the string directly probably shouldn't; instead, they should call > PySSL_SetError to cons up the error name directly from the err code. > However, PySSL_SetError only works after the construction of an ssl > object, which means it can't be used there... I'll take a longer look > at it and see if there's a reasonable fix. Here's a patch which addresses this. It also fixes the indentation in PySSL_SetError, bringing it into line with PEP 7, fixes a compile warning about one of the OpenSSL macros, and makes the namespace a bit more consistent. I've tested it on FC 7 and OS X 10.4. % ./python ./Lib/test/regrtest.py -R :1: -u all test_ssl test_ssl beginning 6 repetitions 123456 ...... 1 test OK. [29244 refs] % [GvR: slightly edited to enforce 79-char line length, even if it required violating the style guide.] ........ r57570 | guido.van.rossum | 2007-08-27 21:11:11 +0200 (Mon, 27 Aug 2007) | 2 lines Patch 10124 by Bill Janssen, docs for the new ssl code. ........ r57574 | guido.van.rossum | 2007-08-27 22:51:00 +0200 (Mon, 27 Aug 2007) | 3 lines Patch # 1739906 by Christian Heimes -- add reduce to functools (importing it from __builtin__). ........ r57575 | guido.van.rossum | 2007-08-27 22:52:10 +0200 (Mon, 27 Aug 2007) | 2 lines News about functools.reduce. ........ r57611 | georg.brandl | 2007-08-28 10:29:08 +0200 (Tue, 28 Aug 2007) | 2 lines Document rev. 57574. ........ r57612 | sean.reifschneider | 2007-08-28 11:07:54 +0200 (Tue, 28 Aug 2007) | 2 lines Adding basic imputil documentation. ........ r57614 | georg.brandl | 2007-08-28 12:48:18 +0200 (Tue, 28 Aug 2007) | 2 lines Fix some glitches. ........ r57616 | lars.gustaebel | 2007-08-28 14:31:09 +0200 (Tue, 28 Aug 2007) | 5 lines TarFile.__init__() no longer fails if no name argument is passed and the fileobj argument has no usable name attribute (e.g. StringIO). (will backport to 2.5) ........ r57619 | thomas.wouters | 2007-08-28 17:28:19 +0200 (Tue, 28 Aug 2007) | 22 lines Improve extended slicing support in builtin types and classes. Specifically: - Specialcase extended slices that amount to a shallow copy the same way as is done for simple slices, in the tuple, string and unicode case. - Specialcase step-1 extended slices to optimize the common case for all involved types. - For lists, allow extended slice assignment of differing lengths as long as the step is 1. (Previously, 'l[:2:1] = []' failed even though 'l[:2] = []' and 'l[:2:None] = []' do not.) - Implement extended slicing for buffer, array, structseq, mmap and UserString.UserString. - Implement slice-object support (but not non-step-1 slice assignment) for UserString.MutableString. - Add tests for all new functionality. ........
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The :mod:`functools` module defines the following functions:
.. function:: cmp_to_key(func)
Transform an old-style comparison function to a :term:`key function`. Used
with tools that accept key functions (such as :func:`sorted`, :func:`min`,
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:func:`max`, :func:`heapq.nlargest`, :func:`heapq.nsmallest`,
:func:`itertools.groupby`). This function is primarily used as a transition
tool for programs being converted from Python 2 which supported the use of
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comparison functions.
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A comparison function is any callable that accept two arguments, compares them,
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and returns a negative number for less-than, zero for equality, or a positive
number for greater-than. A key function is a callable that accepts one
argument and returns another value to be used as the sort key.
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Example::
sorted(iterable, key=cmp_to_key(locale.strcoll)) # locale-aware sort order
For sorting examples and a brief sorting tutorial, see :ref:`sortinghowto`.
.. versionadded:: 3.2
.. decorator:: lru_cache(maxsize=128, typed=False)
Decorator to wrap a function with a memoizing callable that saves up to the
*maxsize* most recent calls. It can save time when an expensive or I/O bound
function is periodically called with the same arguments.
Since a dictionary is used to cache results, the positional and keyword
arguments to the function must be hashable.
If *maxsize* is set to ``None``, the LRU feature is disabled and the cache can
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grow without bound. The LRU feature performs best when *maxsize* is a
power-of-two.
If *typed* is set to true, function arguments of different types will be
cached separately. For example, ``f(3)`` and ``f(3.0)`` will be treated
as distinct calls with distinct results.
To help measure the effectiveness of the cache and tune the *maxsize*
parameter, the wrapped function is instrumented with a :func:`cache_info`
function that returns a :term:`named tuple` showing *hits*, *misses*,
*maxsize* and *currsize*. In a multi-threaded environment, the hits
and misses are approximate.
The decorator also provides a :func:`cache_clear` function for clearing or
invalidating the cache.
The original underlying function is accessible through the
:attr:`__wrapped__` attribute. This is useful for introspection, for
bypassing the cache, or for rewrapping the function with a different cache.
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An `LRU (least recently used) cache
<https://en.wikipedia.org/wiki/Cache_algorithms#Examples>`_ works
best when the most recent calls are the best predictors of upcoming calls (for
example, the most popular articles on a news server tend to change each day).
The cache's size limit assures that the cache does not grow without bound on
long-running processes such as web servers.
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Example of an LRU cache for static web content::
@lru_cache(maxsize=32)
def get_pep(num):
'Retrieve text of a Python Enhancement Proposal'
resource = 'http://www.python.org/dev/peps/pep-%04d/' % num
try:
with urllib.request.urlopen(resource) as s:
return s.read()
except urllib.error.HTTPError:
return 'Not Found'
>>> for n in 8, 290, 308, 320, 8, 218, 320, 279, 289, 320, 9991:
... pep = get_pep(n)
... print(n, len(pep))
>>> get_pep.cache_info()
CacheInfo(hits=3, misses=8, maxsize=32, currsize=8)
Example of efficiently computing
`Fibonacci numbers <https://en.wikipedia.org/wiki/Fibonacci_number>`_
using a cache to implement a
`dynamic programming <https://en.wikipedia.org/wiki/Dynamic_programming>`_
technique::
@lru_cache(maxsize=None)
def fib(n):
if n < 2:
return n
return fib(n-1) + fib(n-2)
>>> [fib(n) for n in range(16)]
[0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610]
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>>> fib.cache_info()
CacheInfo(hits=28, misses=16, maxsize=None, currsize=16)
.. versionadded:: 3.2
.. versionchanged:: 3.3
Added the *typed* option.
.. decorator:: total_ordering
Given a class defining one or more rich comparison ordering methods, this
Merged revisions 79307,79408,79430,79533,79542,79579-79580,79585-79587,79607-79608,79622,79717,79820,79822,79828,79862,79875,79923-79924,79941-79943,79945,79947,79951-79952 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r79307 | florent.xicluna | 2010-03-22 17:45:50 -0500 (Mon, 22 Mar 2010) | 2 lines #7667: Fix doctest failures with non-ASCII paths. ........ r79408 | victor.stinner | 2010-03-24 20:18:38 -0500 (Wed, 24 Mar 2010) | 2 lines Fix a gcc warning introduced by r79397. ........ r79430 | brian.curtin | 2010-03-25 18:48:54 -0500 (Thu, 25 Mar 2010) | 2 lines Fix #6538. Markup RegexObject and MatchObject as classes. Patch by Ryan Arana. ........ r79533 | barry.warsaw | 2010-03-31 16:07:16 -0500 (Wed, 31 Mar 2010) | 6 lines - Issue #8233: When run as a script, py_compile.py optionally takes a single argument `-` which tells it to read files to compile from stdin. Each line is read on demand and the named file is compiled immediately. (Original patch by Piotr O?\197?\188arowski). ........ r79542 | r.david.murray | 2010-03-31 20:28:39 -0500 (Wed, 31 Mar 2010) | 3 lines A couple small grammar fixes in test.rst, and rewrite the check_warnings docs to be clearer. ........ r79579 | georg.brandl | 2010-04-02 03:34:41 -0500 (Fri, 02 Apr 2010) | 1 line Add 2.6.5. ........ r79580 | georg.brandl | 2010-04-02 03:39:09 -0500 (Fri, 02 Apr 2010) | 1 line #2768: add a note on how to get a file descriptor. ........ r79585 | georg.brandl | 2010-04-02 04:03:18 -0500 (Fri, 02 Apr 2010) | 1 line Remove col-spanning cells in logging docs. ........ r79586 | georg.brandl | 2010-04-02 04:07:42 -0500 (Fri, 02 Apr 2010) | 1 line Document PyImport_ExecCodeModuleEx(). ........ r79587 | georg.brandl | 2010-04-02 04:11:49 -0500 (Fri, 02 Apr 2010) | 1 line #8012: clarification in generator glossary entry. ........ r79607 | andrew.kuchling | 2010-04-02 12:48:23 -0500 (Fri, 02 Apr 2010) | 1 line #6647: document that catch_warnings is not thread-safe ........ r79608 | andrew.kuchling | 2010-04-02 12:54:26 -0500 (Fri, 02 Apr 2010) | 1 line #6647: add note to two examples ........ r79622 | tarek.ziade | 2010-04-02 16:34:19 -0500 (Fri, 02 Apr 2010) | 1 line removed documentation on code that was reverted and pushed into distutils2 ........ r79717 | antoine.pitrou | 2010-04-03 16:22:38 -0500 (Sat, 03 Apr 2010) | 4 lines Fix wording / typography, and a slightly misleading statement (memoryviews don't support complex structures right now) ........ r79820 | benjamin.peterson | 2010-04-05 22:34:09 -0500 (Mon, 05 Apr 2010) | 1 line ready _sre types ........ r79822 | georg.brandl | 2010-04-06 03:18:15 -0500 (Tue, 06 Apr 2010) | 1 line #8320: document return value of recv_into(). ........ r79828 | georg.brandl | 2010-04-06 09:33:44 -0500 (Tue, 06 Apr 2010) | 1 line Add JP. ........ r79862 | georg.brandl | 2010-04-06 15:27:59 -0500 (Tue, 06 Apr 2010) | 1 line Fix syntax. ........ r79875 | mark.dickinson | 2010-04-06 17:18:23 -0500 (Tue, 06 Apr 2010) | 1 line More NaN consistency doc fixes. ........ r79923 | georg.brandl | 2010-04-10 06:15:24 -0500 (Sat, 10 Apr 2010) | 1 line #8360: skipTest was added in 2.7. ........ r79924 | georg.brandl | 2010-04-10 06:16:59 -0500 (Sat, 10 Apr 2010) | 1 line #8346: update version. ........ r79941 | andrew.kuchling | 2010-04-10 20:39:36 -0500 (Sat, 10 Apr 2010) | 1 line Two grammar fixes ........ r79942 | andrew.kuchling | 2010-04-10 20:40:06 -0500 (Sat, 10 Apr 2010) | 1 line Punctuation fix ........ r79943 | andrew.kuchling | 2010-04-10 20:40:30 -0500 (Sat, 10 Apr 2010) | 1 line Add various items ........ r79945 | andrew.kuchling | 2010-04-10 20:40:49 -0500 (Sat, 10 Apr 2010) | 1 line name correct ........ r79947 | andrew.kuchling | 2010-04-10 20:44:13 -0500 (Sat, 10 Apr 2010) | 1 line Remove distutils section ........ r79951 | andrew.kuchling | 2010-04-11 07:48:08 -0500 (Sun, 11 Apr 2010) | 1 line Two typo fixes ........ r79952 | andrew.kuchling | 2010-04-11 07:49:37 -0500 (Sun, 11 Apr 2010) | 1 line Add two items ........
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class decorator supplies the rest. This simplifies the effort involved
in specifying all of the possible rich comparison operations:
The class must define one of :meth:`__lt__`, :meth:`__le__`,
:meth:`__gt__`, or :meth:`__ge__`.
In addition, the class should supply an :meth:`__eq__` method.
For example::
@total_ordering
class Student:
def _is_valid_operand(self, other):
return (hasattr(other, "lastname") and
hasattr(other, "firstname"))
def __eq__(self, other):
if not self._is_valid_operand(other):
return NotImplemented
return ((self.lastname.lower(), self.firstname.lower()) ==
(other.lastname.lower(), other.firstname.lower()))
def __lt__(self, other):
if not self._is_valid_operand(other):
return NotImplemented
return ((self.lastname.lower(), self.firstname.lower()) <
(other.lastname.lower(), other.firstname.lower()))
.. note::
While this decorator makes it easy to create well behaved totally
ordered types, it *does* come at the cost of slower execution and
more complex stack traces for the derived comparison methods. If
performance benchmarking indicates this is a bottleneck for a given
application, implementing all six rich comparison methods instead is
likely to provide an easy speed boost.
.. versionadded:: 3.2
.. versionchanged:: 3.4
Returning NotImplemented from the underlying comparison function for
unrecognised types is now supported.
.. function:: partial(func, *args, **keywords)
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Return a new :class:`partial` object which when called will behave like *func*
called with the positional arguments *args* and keyword arguments *keywords*. If
more arguments are supplied to the call, they are appended to *args*. If
additional keyword arguments are supplied, they extend and override *keywords*.
Roughly equivalent to::
def partial(func, *args, **keywords):
def newfunc(*fargs, **fkeywords):
newkeywords = keywords.copy()
newkeywords.update(fkeywords)
return func(*args, *fargs, **newkeywords)
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newfunc.func = func
newfunc.args = args
newfunc.keywords = keywords
return newfunc
The :func:`partial` is used for partial function application which "freezes"
some portion of a function's arguments and/or keywords resulting in a new object
with a simplified signature. For example, :func:`partial` can be used to create
a callable that behaves like the :func:`int` function where the *base* argument
Merged revisions 61724-61725,61731-61735,61737,61739,61741,61743-61744,61753,61761,61765-61767,61769,61773,61776-61778,61780-61783,61788,61793,61796,61807,61813 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ................ r61724 | martin.v.loewis | 2008-03-22 01:01:12 +0100 (Sat, 22 Mar 2008) | 49 lines Merged revisions 61602-61723 via svnmerge from svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3 ........ r61626 | david.wolever | 2008-03-19 17:19:16 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added fixer for implicit local imports. See #2414. ........ r61628 | david.wolever | 2008-03-19 17:57:43 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added a class for tests which should not run if a particular import is found. ........ r61629 | collin.winter | 2008-03-19 17:58:19 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Two more relative import fixes in pgen2. ........ r61635 | david.wolever | 2008-03-19 20:16:03 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Fixed print fixer so it will do the Right Thing when it encounters __future__.print_function. 2to3 gets upset, though, so the tests have been commented out. ........ r61637 | david.wolever | 2008-03-19 21:37:17 +0100 (Mi, 19 M?\195?\164r 2008) | 3 lines Added a fixer for itertools imports (from itertools import imap, ifilterfalse --> from itertools import filterfalse) ........ r61645 | david.wolever | 2008-03-19 23:22:35 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line SVN is happier when you add the files you create... -_-' ........ r61654 | david.wolever | 2008-03-20 01:09:56 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added an explicit sort order to fixers -- fixes problems like #2427 ........ r61664 | david.wolever | 2008-03-20 04:32:40 +0100 (Do, 20 M?\195?\164r 2008) | 3 lines Fixes #2428 -- comments are no longer eatten by __future__ fixer. ........ r61673 | david.wolever | 2008-03-20 17:22:40 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added 2to3 node pretty-printer ........ r61679 | david.wolever | 2008-03-20 20:50:42 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Made node printing a little bit prettier ........ r61723 | martin.v.loewis | 2008-03-22 00:59:27 +0100 (Sa, 22 M?\195?\164r 2008) | 2 lines Fix whitespace. ........ ................ r61725 | martin.v.loewis | 2008-03-22 01:02:41 +0100 (Sat, 22 Mar 2008) | 2 lines Install lib2to3. ................ r61731 | facundo.batista | 2008-03-22 03:45:37 +0100 (Sat, 22 Mar 2008) | 4 lines Small fix that complicated the test actually when that test failed. ................ r61732 | alexandre.vassalotti | 2008-03-22 05:08:44 +0100 (Sat, 22 Mar 2008) | 2 lines Added warning for the removal of 'hotshot' in Py3k. ................ r61733 | georg.brandl | 2008-03-22 11:07:29 +0100 (Sat, 22 Mar 2008) | 4 lines #1918: document that weak references *to* an object are cleared before the object's __del__ is called, to ensure that the weak reference callback (if any) finds the object healthy. ................ r61734 | georg.brandl | 2008-03-22 11:56:23 +0100 (Sat, 22 Mar 2008) | 2 lines Activate the Sphinx doctest extension and convert howto/functional to use it. ................ r61735 | georg.brandl | 2008-03-22 11:58:38 +0100 (Sat, 22 Mar 2008) | 2 lines Allow giving source names on the cmdline. ................ r61737 | georg.brandl | 2008-03-22 12:00:48 +0100 (Sat, 22 Mar 2008) | 2 lines Fixup this HOWTO's doctest blocks so that they can be run with sphinx' doctest builder. ................ r61739 | georg.brandl | 2008-03-22 12:47:10 +0100 (Sat, 22 Mar 2008) | 2 lines Test decimal.rst doctests as far as possible with sphinx doctest. ................ r61741 | georg.brandl | 2008-03-22 13:04:26 +0100 (Sat, 22 Mar 2008) | 2 lines Make doctests in re docs usable with sphinx' doctest. ................ r61743 | georg.brandl | 2008-03-22 13:59:37 +0100 (Sat, 22 Mar 2008) | 2 lines Make more doctests in pprint docs testable. ................ r61744 | georg.brandl | 2008-03-22 14:07:06 +0100 (Sat, 22 Mar 2008) | 2 lines No need to specify explicit "doctest_block" anymore. ................ r61753 | georg.brandl | 2008-03-22 21:08:43 +0100 (Sat, 22 Mar 2008) | 2 lines Fix-up syntax problems. ................ r61761 | georg.brandl | 2008-03-22 22:06:20 +0100 (Sat, 22 Mar 2008) | 4 lines Make collections' doctests executable. (The <BLANKLINE>s will be stripped from presentation output.) ................ r61765 | georg.brandl | 2008-03-22 22:21:57 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in datetime docs. ................ r61766 | georg.brandl | 2008-03-22 22:26:44 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in operator docs. ................ r61767 | georg.brandl | 2008-03-22 22:38:33 +0100 (Sat, 22 Mar 2008) | 2 lines Enable doctests in functions.rst. Already found two errors :) ................ r61769 | georg.brandl | 2008-03-22 23:04:10 +0100 (Sat, 22 Mar 2008) | 3 lines Enable doctest running for several other documents. We have now over 640 doctests that are run with "make doctest". ................ r61773 | raymond.hettinger | 2008-03-23 01:55:46 +0100 (Sun, 23 Mar 2008) | 1 line Simplify demo code. ................ r61776 | neal.norwitz | 2008-03-23 04:43:33 +0100 (Sun, 23 Mar 2008) | 7 lines Try to make this test a little more robust and not fail with: timeout (10.0025) is more than 2 seconds more than expected (0.001) I'm assuming this problem is caused by DNS lookup. This change does a DNS lookup of the hostname before trying to connect, so the time is not included. ................ r61777 | neal.norwitz | 2008-03-23 05:08:30 +0100 (Sun, 23 Mar 2008) | 1 line Speed up the test by avoiding socket timeouts. ................ r61778 | neal.norwitz | 2008-03-23 05:43:09 +0100 (Sun, 23 Mar 2008) | 1 line Skip the epoll test if epoll() does not work ................ r61780 | neal.norwitz | 2008-03-23 06:47:20 +0100 (Sun, 23 Mar 2008) | 1 line Suppress failure (to avoid a flaky test) if we cannot connect to svn.python.org ................ r61781 | neal.norwitz | 2008-03-23 07:13:25 +0100 (Sun, 23 Mar 2008) | 4 lines Move itertools before future_builtins since the latter depends on the former. From a clean build importing future_builtins would fail since itertools wasn't built yet. ................ r61782 | neal.norwitz | 2008-03-23 07:16:04 +0100 (Sun, 23 Mar 2008) | 1 line Try to prevent the alarm going off early in tearDown ................ r61783 | neal.norwitz | 2008-03-23 07:19:57 +0100 (Sun, 23 Mar 2008) | 4 lines Remove compiler warnings (on Alpha at least) about using chars as array subscripts. Using chars are dangerous b/c they are signed on some platforms and unsigned on others. ................ r61788 | georg.brandl | 2008-03-23 09:05:30 +0100 (Sun, 23 Mar 2008) | 2 lines Make the doctests presentation-friendlier. ................ r61793 | amaury.forgeotdarc | 2008-03-23 10:55:29 +0100 (Sun, 23 Mar 2008) | 4 lines #1477: ur'\U0010FFFF' raised in narrow unicode builds. Corrected the raw-unicode-escape codec to use UTF-16 surrogates in this case, just like the unicode-escape codec. ................ r61796 | raymond.hettinger | 2008-03-23 14:32:32 +0100 (Sun, 23 Mar 2008) | 1 line Issue 1681432: Add triangular distribution the random module. ................ r61807 | raymond.hettinger | 2008-03-23 20:37:53 +0100 (Sun, 23 Mar 2008) | 4 lines Adopt Nick's suggestion for useful default arguments. Clean-up floating point issues by adding true division and float constants. ................ r61813 | gregory.p.smith | 2008-03-23 22:04:43 +0100 (Sun, 23 Mar 2008) | 6 lines Fix gzip to deal with CRC's being signed values in Python 2.x properly and to read 32bit values as unsigned to start with rather than applying signedness fixups allover the place afterwards. This hopefully fixes the test_tarfile failure on the alpha/tru64 buildbot. ................
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defaults to two:
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Merged revisions 61724-61725,61731-61735,61737,61739,61741,61743-61744,61753,61761,61765-61767,61769,61773,61776-61778,61780-61783,61788,61793,61796,61807,61813 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ................ r61724 | martin.v.loewis | 2008-03-22 01:01:12 +0100 (Sat, 22 Mar 2008) | 49 lines Merged revisions 61602-61723 via svnmerge from svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3 ........ r61626 | david.wolever | 2008-03-19 17:19:16 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added fixer for implicit local imports. See #2414. ........ r61628 | david.wolever | 2008-03-19 17:57:43 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added a class for tests which should not run if a particular import is found. ........ r61629 | collin.winter | 2008-03-19 17:58:19 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Two more relative import fixes in pgen2. ........ r61635 | david.wolever | 2008-03-19 20:16:03 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Fixed print fixer so it will do the Right Thing when it encounters __future__.print_function. 2to3 gets upset, though, so the tests have been commented out. ........ r61637 | david.wolever | 2008-03-19 21:37:17 +0100 (Mi, 19 M?\195?\164r 2008) | 3 lines Added a fixer for itertools imports (from itertools import imap, ifilterfalse --> from itertools import filterfalse) ........ r61645 | david.wolever | 2008-03-19 23:22:35 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line SVN is happier when you add the files you create... -_-' ........ r61654 | david.wolever | 2008-03-20 01:09:56 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added an explicit sort order to fixers -- fixes problems like #2427 ........ r61664 | david.wolever | 2008-03-20 04:32:40 +0100 (Do, 20 M?\195?\164r 2008) | 3 lines Fixes #2428 -- comments are no longer eatten by __future__ fixer. ........ r61673 | david.wolever | 2008-03-20 17:22:40 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added 2to3 node pretty-printer ........ r61679 | david.wolever | 2008-03-20 20:50:42 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Made node printing a little bit prettier ........ r61723 | martin.v.loewis | 2008-03-22 00:59:27 +0100 (Sa, 22 M?\195?\164r 2008) | 2 lines Fix whitespace. ........ ................ r61725 | martin.v.loewis | 2008-03-22 01:02:41 +0100 (Sat, 22 Mar 2008) | 2 lines Install lib2to3. ................ r61731 | facundo.batista | 2008-03-22 03:45:37 +0100 (Sat, 22 Mar 2008) | 4 lines Small fix that complicated the test actually when that test failed. ................ r61732 | alexandre.vassalotti | 2008-03-22 05:08:44 +0100 (Sat, 22 Mar 2008) | 2 lines Added warning for the removal of 'hotshot' in Py3k. ................ r61733 | georg.brandl | 2008-03-22 11:07:29 +0100 (Sat, 22 Mar 2008) | 4 lines #1918: document that weak references *to* an object are cleared before the object's __del__ is called, to ensure that the weak reference callback (if any) finds the object healthy. ................ r61734 | georg.brandl | 2008-03-22 11:56:23 +0100 (Sat, 22 Mar 2008) | 2 lines Activate the Sphinx doctest extension and convert howto/functional to use it. ................ r61735 | georg.brandl | 2008-03-22 11:58:38 +0100 (Sat, 22 Mar 2008) | 2 lines Allow giving source names on the cmdline. ................ r61737 | georg.brandl | 2008-03-22 12:00:48 +0100 (Sat, 22 Mar 2008) | 2 lines Fixup this HOWTO's doctest blocks so that they can be run with sphinx' doctest builder. ................ r61739 | georg.brandl | 2008-03-22 12:47:10 +0100 (Sat, 22 Mar 2008) | 2 lines Test decimal.rst doctests as far as possible with sphinx doctest. ................ r61741 | georg.brandl | 2008-03-22 13:04:26 +0100 (Sat, 22 Mar 2008) | 2 lines Make doctests in re docs usable with sphinx' doctest. ................ r61743 | georg.brandl | 2008-03-22 13:59:37 +0100 (Sat, 22 Mar 2008) | 2 lines Make more doctests in pprint docs testable. ................ r61744 | georg.brandl | 2008-03-22 14:07:06 +0100 (Sat, 22 Mar 2008) | 2 lines No need to specify explicit "doctest_block" anymore. ................ r61753 | georg.brandl | 2008-03-22 21:08:43 +0100 (Sat, 22 Mar 2008) | 2 lines Fix-up syntax problems. ................ r61761 | georg.brandl | 2008-03-22 22:06:20 +0100 (Sat, 22 Mar 2008) | 4 lines Make collections' doctests executable. (The <BLANKLINE>s will be stripped from presentation output.) ................ r61765 | georg.brandl | 2008-03-22 22:21:57 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in datetime docs. ................ r61766 | georg.brandl | 2008-03-22 22:26:44 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in operator docs. ................ r61767 | georg.brandl | 2008-03-22 22:38:33 +0100 (Sat, 22 Mar 2008) | 2 lines Enable doctests in functions.rst. Already found two errors :) ................ r61769 | georg.brandl | 2008-03-22 23:04:10 +0100 (Sat, 22 Mar 2008) | 3 lines Enable doctest running for several other documents. We have now over 640 doctests that are run with "make doctest". ................ r61773 | raymond.hettinger | 2008-03-23 01:55:46 +0100 (Sun, 23 Mar 2008) | 1 line Simplify demo code. ................ r61776 | neal.norwitz | 2008-03-23 04:43:33 +0100 (Sun, 23 Mar 2008) | 7 lines Try to make this test a little more robust and not fail with: timeout (10.0025) is more than 2 seconds more than expected (0.001) I'm assuming this problem is caused by DNS lookup. This change does a DNS lookup of the hostname before trying to connect, so the time is not included. ................ r61777 | neal.norwitz | 2008-03-23 05:08:30 +0100 (Sun, 23 Mar 2008) | 1 line Speed up the test by avoiding socket timeouts. ................ r61778 | neal.norwitz | 2008-03-23 05:43:09 +0100 (Sun, 23 Mar 2008) | 1 line Skip the epoll test if epoll() does not work ................ r61780 | neal.norwitz | 2008-03-23 06:47:20 +0100 (Sun, 23 Mar 2008) | 1 line Suppress failure (to avoid a flaky test) if we cannot connect to svn.python.org ................ r61781 | neal.norwitz | 2008-03-23 07:13:25 +0100 (Sun, 23 Mar 2008) | 4 lines Move itertools before future_builtins since the latter depends on the former. From a clean build importing future_builtins would fail since itertools wasn't built yet. ................ r61782 | neal.norwitz | 2008-03-23 07:16:04 +0100 (Sun, 23 Mar 2008) | 1 line Try to prevent the alarm going off early in tearDown ................ r61783 | neal.norwitz | 2008-03-23 07:19:57 +0100 (Sun, 23 Mar 2008) | 4 lines Remove compiler warnings (on Alpha at least) about using chars as array subscripts. Using chars are dangerous b/c they are signed on some platforms and unsigned on others. ................ r61788 | georg.brandl | 2008-03-23 09:05:30 +0100 (Sun, 23 Mar 2008) | 2 lines Make the doctests presentation-friendlier. ................ r61793 | amaury.forgeotdarc | 2008-03-23 10:55:29 +0100 (Sun, 23 Mar 2008) | 4 lines #1477: ur'\U0010FFFF' raised in narrow unicode builds. Corrected the raw-unicode-escape codec to use UTF-16 surrogates in this case, just like the unicode-escape codec. ................ r61796 | raymond.hettinger | 2008-03-23 14:32:32 +0100 (Sun, 23 Mar 2008) | 1 line Issue 1681432: Add triangular distribution the random module. ................ r61807 | raymond.hettinger | 2008-03-23 20:37:53 +0100 (Sun, 23 Mar 2008) | 4 lines Adopt Nick's suggestion for useful default arguments. Clean-up floating point issues by adding true division and float constants. ................ r61813 | gregory.p.smith | 2008-03-23 22:04:43 +0100 (Sun, 23 Mar 2008) | 6 lines Fix gzip to deal with CRC's being signed values in Python 2.x properly and to read 32bit values as unsigned to start with rather than applying signedness fixups allover the place afterwards. This hopefully fixes the test_tarfile failure on the alpha/tru64 buildbot. ................
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>>> from functools import partial
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>>> basetwo = partial(int, base=2)
>>> basetwo.__doc__ = 'Convert base 2 string to an int.'
>>> basetwo('10010')
18
.. class:: partialmethod(func, *args, **keywords)
Return a new :class:`partialmethod` descriptor which behaves
like :class:`partial` except that it is designed to be used as a method
definition rather than being directly callable.
*func* must be a :term:`descriptor` or a callable (objects which are both,
like normal functions, are handled as descriptors).
When *func* is a descriptor (such as a normal Python function,
:func:`classmethod`, :func:`staticmethod`, :func:`abstractmethod` or
another instance of :class:`partialmethod`), calls to ``__get__`` are
delegated to the underlying descriptor, and an appropriate
:class:`partial` object returned as the result.
When *func* is a non-descriptor callable, an appropriate bound method is
created dynamically. This behaves like a normal Python function when
used as a method: the *self* argument will be inserted as the first
positional argument, even before the *args* and *keywords* supplied to
the :class:`partialmethod` constructor.
Example::
>>> class Cell(object):
... def __init__(self):
... self._alive = False
... @property
... def alive(self):
... return self._alive
... def set_state(self, state):
... self._alive = bool(state)
... set_alive = partialmethod(set_state, True)
... set_dead = partialmethod(set_state, False)
...
>>> c = Cell()
>>> c.alive
False
>>> c.set_alive()
>>> c.alive
True
.. versionadded:: 3.4
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.. function:: reduce(function, iterable[, initializer])
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Apply *function* of two arguments cumulatively to the items of *sequence*, from
left to right, so as to reduce the sequence to a single value. For example,
``reduce(lambda x, y: x+y, [1, 2, 3, 4, 5])`` calculates ``((((1+2)+3)+4)+5)``.
The left argument, *x*, is the accumulated value and the right argument, *y*, is
the update value from the *sequence*. If the optional *initializer* is present,
it is placed before the items of the sequence in the calculation, and serves as
a default when the sequence is empty. If *initializer* is not given and
*sequence* contains only one item, the first item is returned.
Roughly equivalent to::
def reduce(function, iterable, initializer=None):
it = iter(iterable)
if initializer is None:
value = next(it)
else:
value = initializer
for element in it:
value = function(value, element)
return value
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.. decorator:: singledispatch
Transform a function into a :term:`single-dispatch <single
dispatch>` :term:`generic function`.
To define a generic function, decorate it with the ``@singledispatch``
decorator. Note that the dispatch happens on the type of the first argument,
create your function accordingly::
>>> from functools import singledispatch
>>> @singledispatch
... def fun(arg, verbose=False):
... if verbose:
... print("Let me just say,", end=" ")
... print(arg)
To add overloaded implementations to the function, use the :func:`register`
attribute of the generic function. It is a decorator. For functions
annotated with types, the decorator will infer the type of the first
argument automatically::
>>> @fun.register
... def _(arg: int, verbose=False):
... if verbose:
... print("Strength in numbers, eh?", end=" ")
... print(arg)
...
>>> @fun.register
... def _(arg: list, verbose=False):
... if verbose:
... print("Enumerate this:")
... for i, elem in enumerate(arg):
... print(i, elem)
For code which doesn't use type annotations, the appropriate type
argument can be passed explicitly to the decorator itself::
>>> @fun.register(complex)
... def _(arg, verbose=False):
... if verbose:
... print("Better than complicated.", end=" ")
... print(arg.real, arg.imag)
...
To enable registering lambdas and pre-existing functions, the
:func:`register` attribute can be used in a functional form::
>>> def nothing(arg, verbose=False):
... print("Nothing.")
...
>>> fun.register(type(None), nothing)
The :func:`register` attribute returns the undecorated function which
enables decorator stacking, pickling, as well as creating unit tests for
each variant independently::
>>> @fun.register(float)
... @fun.register(Decimal)
... def fun_num(arg, verbose=False):
... if verbose:
... print("Half of your number:", end=" ")
... print(arg / 2)
...
>>> fun_num is fun
False
When called, the generic function dispatches on the type of the first
argument::
>>> fun("Hello, world.")
Hello, world.
>>> fun("test.", verbose=True)
Let me just say, test.
>>> fun(42, verbose=True)
Strength in numbers, eh? 42
>>> fun(['spam', 'spam', 'eggs', 'spam'], verbose=True)
Enumerate this:
0 spam
1 spam
2 eggs
3 spam
>>> fun(None)
Nothing.
>>> fun(1.23)
0.615
Where there is no registered implementation for a specific type, its
method resolution order is used to find a more generic implementation.
The original function decorated with ``@singledispatch`` is registered
for the base ``object`` type, which means it is used if no better
implementation is found.
To check which implementation will the generic function choose for
a given type, use the ``dispatch()`` attribute::
>>> fun.dispatch(float)
<function fun_num at 0x1035a2840>
>>> fun.dispatch(dict) # note: default implementation
<function fun at 0x103fe0000>
To access all registered implementations, use the read-only ``registry``
attribute::
>>> fun.registry.keys()
dict_keys([<class 'NoneType'>, <class 'int'>, <class 'object'>,
<class 'decimal.Decimal'>, <class 'list'>,
<class 'float'>])
>>> fun.registry[float]
<function fun_num at 0x1035a2840>
>>> fun.registry[object]
<function fun at 0x103fe0000>
.. versionadded:: 3.4
.. versionchanged:: 3.7
The :func:`register` attribute supports using type annotations.
.. function:: update_wrapper(wrapper, wrapped, assigned=WRAPPER_ASSIGNMENTS, updated=WRAPPER_UPDATES)
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Update a *wrapper* function to look like the *wrapped* function. The optional
arguments are tuples to specify which attributes of the original function are
assigned directly to the matching attributes on the wrapper function and which
attributes of the wrapper function are updated with the corresponding attributes
from the original function. The default values for these arguments are the
module level constants ``WRAPPER_ASSIGNMENTS`` (which assigns to the wrapper
function's ``__module__``, ``__name__``, ``__qualname__``, ``__annotations__``
and ``__doc__``, the documentation string) and ``WRAPPER_UPDATES`` (which
updates the wrapper function's ``__dict__``, i.e. the instance dictionary).
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To allow access to the original function for introspection and other purposes
(e.g. bypassing a caching decorator such as :func:`lru_cache`), this function
automatically adds a ``__wrapped__`` attribute to the wrapper that refers to
the function being wrapped.
Merged revisions 59259-59274 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r59260 | lars.gustaebel | 2007-12-01 22:02:12 +0100 (Sat, 01 Dec 2007) | 5 lines Issue #1531: Read fileobj from the current offset, do not seek to the start. (will backport to 2.5) ........ r59262 | georg.brandl | 2007-12-01 23:24:47 +0100 (Sat, 01 Dec 2007) | 4 lines Document PyEval_* functions from ceval.c. Credits to Michael Sloan from GHOP. ........ r59263 | georg.brandl | 2007-12-01 23:27:56 +0100 (Sat, 01 Dec 2007) | 2 lines Add a few refcount data entries. ........ r59264 | georg.brandl | 2007-12-01 23:38:48 +0100 (Sat, 01 Dec 2007) | 4 lines Add test suite for cmd module. Written by Michael Schneider for GHOP. ........ r59265 | georg.brandl | 2007-12-01 23:42:46 +0100 (Sat, 01 Dec 2007) | 3 lines Add examples to the ElementTree documentation. Written by h4wk.cz for GHOP. ........ r59266 | georg.brandl | 2007-12-02 00:12:45 +0100 (Sun, 02 Dec 2007) | 3 lines Add "Using Python on Windows" document, by Robert Lehmann. Written for GHOP. ........ r59271 | georg.brandl | 2007-12-02 15:34:34 +0100 (Sun, 02 Dec 2007) | 3 lines Add example to mmap docs. Written for GHOP by Rafal Rawicki. ........ r59272 | georg.brandl | 2007-12-02 15:37:29 +0100 (Sun, 02 Dec 2007) | 2 lines Convert bdb.rst line endings to Unix style. ........ r59274 | georg.brandl | 2007-12-02 15:58:50 +0100 (Sun, 02 Dec 2007) | 4 lines Add more entries to the glossary. Written by Jeff Wheeler for GHOP. ........
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The main intended use for this function is in :term:`decorator` functions which
wrap the decorated function and return the wrapper. If the wrapper function is
not updated, the metadata of the returned function will reflect the wrapper
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definition rather than the original function definition, which is typically less
than helpful.
:func:`update_wrapper` may be used with callables other than functions. Any
attributes named in *assigned* or *updated* that are missing from the object
being wrapped are ignored (i.e. this function will not attempt to set them
on the wrapper function). :exc:`AttributeError` is still raised if the
wrapper function itself is missing any attributes named in *updated*.
.. versionadded:: 3.2
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Automatic addition of the ``__wrapped__`` attribute.
.. versionadded:: 3.2
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Copying of the ``__annotations__`` attribute by default.
.. versionchanged:: 3.2
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Missing attributes no longer trigger an :exc:`AttributeError`.
.. versionchanged:: 3.4
The ``__wrapped__`` attribute now always refers to the wrapped
function, even if that function defined a ``__wrapped__`` attribute.
(see :issue:`17482`)
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.. decorator:: wraps(wrapped, assigned=WRAPPER_ASSIGNMENTS, updated=WRAPPER_UPDATES)
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This is a convenience function for invoking :func:`update_wrapper` as a
function decorator when defining a wrapper function. It is equivalent to
``partial(update_wrapper, wrapped=wrapped, assigned=assigned, updated=updated)``.
For example::
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Merged revisions 61724-61725,61731-61735,61737,61739,61741,61743-61744,61753,61761,61765-61767,61769,61773,61776-61778,61780-61783,61788,61793,61796,61807,61813 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ................ r61724 | martin.v.loewis | 2008-03-22 01:01:12 +0100 (Sat, 22 Mar 2008) | 49 lines Merged revisions 61602-61723 via svnmerge from svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3 ........ r61626 | david.wolever | 2008-03-19 17:19:16 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added fixer for implicit local imports. See #2414. ........ r61628 | david.wolever | 2008-03-19 17:57:43 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Added a class for tests which should not run if a particular import is found. ........ r61629 | collin.winter | 2008-03-19 17:58:19 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Two more relative import fixes in pgen2. ........ r61635 | david.wolever | 2008-03-19 20:16:03 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line Fixed print fixer so it will do the Right Thing when it encounters __future__.print_function. 2to3 gets upset, though, so the tests have been commented out. ........ r61637 | david.wolever | 2008-03-19 21:37:17 +0100 (Mi, 19 M?\195?\164r 2008) | 3 lines Added a fixer for itertools imports (from itertools import imap, ifilterfalse --> from itertools import filterfalse) ........ r61645 | david.wolever | 2008-03-19 23:22:35 +0100 (Mi, 19 M?\195?\164r 2008) | 1 line SVN is happier when you add the files you create... -_-' ........ r61654 | david.wolever | 2008-03-20 01:09:56 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added an explicit sort order to fixers -- fixes problems like #2427 ........ r61664 | david.wolever | 2008-03-20 04:32:40 +0100 (Do, 20 M?\195?\164r 2008) | 3 lines Fixes #2428 -- comments are no longer eatten by __future__ fixer. ........ r61673 | david.wolever | 2008-03-20 17:22:40 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Added 2to3 node pretty-printer ........ r61679 | david.wolever | 2008-03-20 20:50:42 +0100 (Do, 20 M?\195?\164r 2008) | 1 line Made node printing a little bit prettier ........ r61723 | martin.v.loewis | 2008-03-22 00:59:27 +0100 (Sa, 22 M?\195?\164r 2008) | 2 lines Fix whitespace. ........ ................ r61725 | martin.v.loewis | 2008-03-22 01:02:41 +0100 (Sat, 22 Mar 2008) | 2 lines Install lib2to3. ................ r61731 | facundo.batista | 2008-03-22 03:45:37 +0100 (Sat, 22 Mar 2008) | 4 lines Small fix that complicated the test actually when that test failed. ................ r61732 | alexandre.vassalotti | 2008-03-22 05:08:44 +0100 (Sat, 22 Mar 2008) | 2 lines Added warning for the removal of 'hotshot' in Py3k. ................ r61733 | georg.brandl | 2008-03-22 11:07:29 +0100 (Sat, 22 Mar 2008) | 4 lines #1918: document that weak references *to* an object are cleared before the object's __del__ is called, to ensure that the weak reference callback (if any) finds the object healthy. ................ r61734 | georg.brandl | 2008-03-22 11:56:23 +0100 (Sat, 22 Mar 2008) | 2 lines Activate the Sphinx doctest extension and convert howto/functional to use it. ................ r61735 | georg.brandl | 2008-03-22 11:58:38 +0100 (Sat, 22 Mar 2008) | 2 lines Allow giving source names on the cmdline. ................ r61737 | georg.brandl | 2008-03-22 12:00:48 +0100 (Sat, 22 Mar 2008) | 2 lines Fixup this HOWTO's doctest blocks so that they can be run with sphinx' doctest builder. ................ r61739 | georg.brandl | 2008-03-22 12:47:10 +0100 (Sat, 22 Mar 2008) | 2 lines Test decimal.rst doctests as far as possible with sphinx doctest. ................ r61741 | georg.brandl | 2008-03-22 13:04:26 +0100 (Sat, 22 Mar 2008) | 2 lines Make doctests in re docs usable with sphinx' doctest. ................ r61743 | georg.brandl | 2008-03-22 13:59:37 +0100 (Sat, 22 Mar 2008) | 2 lines Make more doctests in pprint docs testable. ................ r61744 | georg.brandl | 2008-03-22 14:07:06 +0100 (Sat, 22 Mar 2008) | 2 lines No need to specify explicit "doctest_block" anymore. ................ r61753 | georg.brandl | 2008-03-22 21:08:43 +0100 (Sat, 22 Mar 2008) | 2 lines Fix-up syntax problems. ................ r61761 | georg.brandl | 2008-03-22 22:06:20 +0100 (Sat, 22 Mar 2008) | 4 lines Make collections' doctests executable. (The <BLANKLINE>s will be stripped from presentation output.) ................ r61765 | georg.brandl | 2008-03-22 22:21:57 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in datetime docs. ................ r61766 | georg.brandl | 2008-03-22 22:26:44 +0100 (Sat, 22 Mar 2008) | 2 lines Test doctests in operator docs. ................ r61767 | georg.brandl | 2008-03-22 22:38:33 +0100 (Sat, 22 Mar 2008) | 2 lines Enable doctests in functions.rst. Already found two errors :) ................ r61769 | georg.brandl | 2008-03-22 23:04:10 +0100 (Sat, 22 Mar 2008) | 3 lines Enable doctest running for several other documents. We have now over 640 doctests that are run with "make doctest". ................ r61773 | raymond.hettinger | 2008-03-23 01:55:46 +0100 (Sun, 23 Mar 2008) | 1 line Simplify demo code. ................ r61776 | neal.norwitz | 2008-03-23 04:43:33 +0100 (Sun, 23 Mar 2008) | 7 lines Try to make this test a little more robust and not fail with: timeout (10.0025) is more than 2 seconds more than expected (0.001) I'm assuming this problem is caused by DNS lookup. This change does a DNS lookup of the hostname before trying to connect, so the time is not included. ................ r61777 | neal.norwitz | 2008-03-23 05:08:30 +0100 (Sun, 23 Mar 2008) | 1 line Speed up the test by avoiding socket timeouts. ................ r61778 | neal.norwitz | 2008-03-23 05:43:09 +0100 (Sun, 23 Mar 2008) | 1 line Skip the epoll test if epoll() does not work ................ r61780 | neal.norwitz | 2008-03-23 06:47:20 +0100 (Sun, 23 Mar 2008) | 1 line Suppress failure (to avoid a flaky test) if we cannot connect to svn.python.org ................ r61781 | neal.norwitz | 2008-03-23 07:13:25 +0100 (Sun, 23 Mar 2008) | 4 lines Move itertools before future_builtins since the latter depends on the former. From a clean build importing future_builtins would fail since itertools wasn't built yet. ................ r61782 | neal.norwitz | 2008-03-23 07:16:04 +0100 (Sun, 23 Mar 2008) | 1 line Try to prevent the alarm going off early in tearDown ................ r61783 | neal.norwitz | 2008-03-23 07:19:57 +0100 (Sun, 23 Mar 2008) | 4 lines Remove compiler warnings (on Alpha at least) about using chars as array subscripts. Using chars are dangerous b/c they are signed on some platforms and unsigned on others. ................ r61788 | georg.brandl | 2008-03-23 09:05:30 +0100 (Sun, 23 Mar 2008) | 2 lines Make the doctests presentation-friendlier. ................ r61793 | amaury.forgeotdarc | 2008-03-23 10:55:29 +0100 (Sun, 23 Mar 2008) | 4 lines #1477: ur'\U0010FFFF' raised in narrow unicode builds. Corrected the raw-unicode-escape codec to use UTF-16 surrogates in this case, just like the unicode-escape codec. ................ r61796 | raymond.hettinger | 2008-03-23 14:32:32 +0100 (Sun, 23 Mar 2008) | 1 line Issue 1681432: Add triangular distribution the random module. ................ r61807 | raymond.hettinger | 2008-03-23 20:37:53 +0100 (Sun, 23 Mar 2008) | 4 lines Adopt Nick's suggestion for useful default arguments. Clean-up floating point issues by adding true division and float constants. ................ r61813 | gregory.p.smith | 2008-03-23 22:04:43 +0100 (Sun, 23 Mar 2008) | 6 lines Fix gzip to deal with CRC's being signed values in Python 2.x properly and to read 32bit values as unsigned to start with rather than applying signedness fixups allover the place afterwards. This hopefully fixes the test_tarfile failure on the alpha/tru64 buildbot. ................
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>>> from functools import wraps
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>>> def my_decorator(f):
... @wraps(f)
... def wrapper(*args, **kwds):
... print('Calling decorated function')
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... return f(*args, **kwds)
... return wrapper
...
>>> @my_decorator
... def example():
... """Docstring"""
... print('Called example function')
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...
>>> example()
Calling decorated function
Called example function
>>> example.__name__
'example'
>>> example.__doc__
'Docstring'
Without the use of this decorator factory, the name of the example function
would have been ``'wrapper'``, and the docstring of the original :func:`example`
would have been lost.
.. _partial-objects:
:class:`partial` Objects
------------------------
:class:`partial` objects are callable objects created by :func:`partial`. They
have three read-only attributes:
.. attribute:: partial.func
A callable object or function. Calls to the :class:`partial` object will be
forwarded to :attr:`func` with new arguments and keywords.
.. attribute:: partial.args
The leftmost positional arguments that will be prepended to the positional
arguments provided to a :class:`partial` object call.
.. attribute:: partial.keywords
The keyword arguments that will be supplied when the :class:`partial` object is
called.
:class:`partial` objects are like :class:`function` objects in that they are
callable, weak referencable, and can have attributes. There are some important
differences. For instance, the :attr:`~definition.__name__` and :attr:`__doc__` attributes
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are not created automatically. Also, :class:`partial` objects defined in
classes behave like static methods and do not transform into bound methods
during instance attribute look-up.