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Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001+++++++++++
2Python News
3+++++++++++
4
Skip Montanaro4a385832002-09-20 17:08:52 +00005(editors: check NEWS.help for information about editing NEWS using ReST.)
6
Martin v. Löwis14e73b12003-01-01 09:51:12 +00007What's New in Python 2.3 alpha 2?
8=================================
9
David Goodgerf349e262003-01-03 03:30:21 +000010*Release date: XX-XXX-2003*
Martin v. Löwis14e73b12003-01-01 09:51:12 +000011
12Core and builtins
Guido van Rossumc4f4ca92003-02-12 21:46:11 +000013-----------------
Martin v. Löwis14e73b12003-01-01 09:51:12 +000014
Walter Dörwald2ffec022003-02-19 16:34:11 +000015- Negative positions returned from PEP 293 error callbacks are now
16 treated as being relative to the end of the input string. Positions
17 that are out of bounds raise an IndexError.
18
Guido van Rossum162e38c2003-02-19 15:25:10 +000019- sys.path[0] (the directory from which the script is loaded) is now
20 turned into an absolute pathname, unless it is the empty string.
21 (SF patch #664376.)
22
Guido van Rossum4b499dd32003-02-13 22:07:59 +000023- Finally fixed the bug in compile() and exec where a string ending
24 with an indented code block but no newline would raise SyntaxError.
25 This would have been a four-line change in parsetok.c... Except
26 codeop.py depends on this behavior, so a compilation flag had to be
27 invented that causes the tokenizer to revert to the old behavior;
28 this required extra changes to 2 .h files, 2 .c files, and 2 .py
Guido van Rossum1442dc12003-02-13 22:19:20 +000029 files. (Fixes SF bug #501622.)
Guido van Rossum4b499dd32003-02-13 22:07:59 +000030
Guido van Rossum298e4212003-02-13 16:30:16 +000031- If a new-style class defines neither __new__ nor __init__, its
32 constructor would ignore all arguments. This is changed now: the
33 constructor refuses arguments in this case. This might break code
34 that worked under Python 2.2. The simplest fix is to add a no-op
35 __init__: "def __init__(self, *args, **kw): pass".
36
Guido van Rossum48035eb2003-02-12 17:05:26 +000037- Through a bytecode optimizer bug (and I bet you didn't even know
38 Python *had* a bytecode optimizer :-), "unsigned" hex/oct constants
39 with a leading minus sign would come out with the wrong sign.
40 ("Unsigned" hex/oct constants are those with a face value in the
41 range sys.maxint+1 through sys.maxint*2+1, inclusive; these have
42 always been interpreted as negative numbers through sign folding.)
43 E.g. 0xffffffff is -1, and -(0xffffffff) is 1, but -0xffffffff would
44 come out as -4294967295. This was the case in Python 2.2 through
45 2.2.2 and 2.3a1, and in Python 2.4 it will once again have that
46 value, but according to PEP 237 it really needs to be 1 now. This
47 will be backported to Python 2.2.3 a well. (SF #660455)
48
Guido van Rossum47710652003-02-12 20:48:22 +000049- int(s, base) sometimes sign-folds hex and oct constants; it only
50 does this when base is 0 and s.strip() starts with a '0'. When the
51 sign is actually folded, as in int("0xffffffff", 0) on a 32-bit
52 machine, which returns -1, a FutureWarning is now issued; in Python
53 2.4, this will return 4294967295L, as do int("+0xffffffff", 0) and
54 int("0xffffffff", 16) right now. (PEP 347)
55
Guido van Rossuma89d10e2003-02-12 03:58:38 +000056- super(X, x): x may now be a proxy for an X instance, i.e.
57 issubclass(x.__class__, X) but not issubclass(type(x), X).
58
Guido van Rossum03bc7d32003-02-12 03:32:58 +000059- isinstance(x, X): if X is a new-style class, this is now equivalent
60 to issubclass(type(x), X) or issubclass(x.__class__, X). Previously
61 only type(x) was tested. (For classic classes this was already the
62 case.)
63
Just van Rossum73ffb4a2003-02-10 09:57:08 +000064- compile(), eval() and the exec statement now fully support source code
65 passed as unicode strings.
66
Neal Norwitzde8b94c2003-02-10 02:12:43 +000067- int subclasses can be initialized with longs if the value fits in an int.
68 See SF bug #683467.
69
Tim Petersbf2674b2003-02-02 07:51:32 +000070- long(string, base) takes time linear in len(string) when base is a power
71 of 2 now. It used to take time quadratic in len(string).
72
Martin v. Löwis8afd7572003-01-25 22:46:11 +000073- filter returns now Unicode results for Unicode arguments.
74
Martin v. Löwisaf6a27a2003-01-03 19:16:14 +000075- raw_input can now return Unicode objects.
76
Skip Montanaro4abd5f02003-01-02 20:51:08 +000077- List objects' sort() method now accepts None as the comparison function.
78 Passing None is semantically identical to calling sort() with no
79 arguments.
80
Neal Norwitz1a997502003-01-13 20:13:12 +000081- Fixed crash when printing a subclass of str and __str__ returned self.
82 See SF bug #667147.
83
Neal Norwitzabcb0c02003-01-28 19:21:24 +000084- Fixed an invalid RuntimeWarning and an undetected error when trying
Tim Peters506be282003-01-31 22:27:17 +000085 to convert a long integer into a float which couldn't fit.
Neal Norwitzabcb0c02003-01-28 19:21:24 +000086 See SF bug #676155.
87
Guido van Rossum26507db2003-02-06 16:16:50 +000088- Function objects now have a __module__ attribute that is bound to
Jeremy Hylton0253d6e2003-02-06 16:00:15 +000089 the name of the module in which the function was defined. This
Guido van Rossum26507db2003-02-06 16:16:50 +000090 applies for C functions and methods as well as functions and methods
91 defined in Python. This attribute is used by pickle.whichmodule(),
92 which changes the behavior of whichmodule slightly. In Python 2.2
93 whichmodule() returns "__main__" for functions that are not defined
94 at the top-level of a module (examples: methods, nested functions).
95 Now whichmodule() will return the proper module name.
Jeremy Hylton0253d6e2003-02-06 16:00:15 +000096
Martin v. Löwis14e73b12003-01-01 09:51:12 +000097Extension modules
98-----------------
99
Guido van Rossum6921eca2003-02-18 16:36:28 +0000100- operator.isNumberType() now checks that the object has a nb_int or
101 nb_float slot, rather than simply checking whether it has a non-NULL
102 tp_as_number pointer.
103
Guido van Rossumc4f4ca92003-02-12 21:46:11 +0000104- The imp module now has ways to acquire and release the "import
105 lock": imp.acquire_lock() and imp.release_lock(). Note: this is a
106 reentrant lock, so releasing the lock only truly releases it when
107 this is the last release_lock() call. You can check with
108 imp.lock_held(). (SF bug #580952 and patch #683257.)
109
Neal Norwitz9caf9c02003-02-10 01:54:06 +0000110- Fix some bugs in the parser module. SF bug #678518.
111
Guido van Rossum7d9ea502003-02-03 20:45:52 +0000112- Thanks to Scott David Daniels, a subtle bug in how the zlib
Walter Dörwald28d81962003-02-03 20:53:14 +0000113 extension implemented flush() was fixed. Scott also rewrote the
Guido van Rossum7d9ea502003-02-03 20:45:52 +0000114 zlib test suite using the unittest module. (SF bug #640230 and
115 patch #678531.)
116
Raymond Hettinger96ef8112003-02-01 00:10:11 +0000117- Added an itertools module containing high speed, memory efficient
118 looping constructs inspired by tools from Haskell and SML.
119
Guido van Rossum99d4abf2003-01-27 22:22:50 +0000120- The SSL module now handles sockets with a timeout set correctly (SF
121 patch #675750, fixing SF bug #675552).
122
Martin v. Löwis9789aef2003-01-26 11:30:36 +0000123- A new module _iconv_codec has been added, to expose the iconv(3)
124 library.
125
Barry Warsawf8ba39c2003-01-07 20:55:26 +0000126- os/posixmodule has grown the sysexits.h constants (EX_OK and friends).
127
Guido van Rossum6d0d3652003-01-07 20:34:19 +0000128- Fixed broken threadstate swap in readline that could cause fatal
129 errors when a readline hook was being invoked while a background
130 thread was active. (SF bugs #660476 and #513033.)
131
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000132- fcntl now exposes the strops.h I_* constants.
133
Tim Peters00640262003-01-24 15:31:31 +0000134- Fix a crash on Solaris that occurred when calling close() on
135 an mmap'ed file which was already closed. (SF patch #665913)
136
Tim Peters01231392003-01-02 19:10:19 +0000137- datetime changes:
138
Tim Peters0bf60bd2003-01-08 20:40:01 +0000139 The datetime and datetimetz classes have been collapsed into a single
140 datetime class, and likewise the time and timetz classes into a single
141 time class. Previously, a datetimetz object with tzinfo=None acted
142 exactly like a datetime object, and similarly for timetz. This wasn't
143 enough of a difference to justify distinct classes, and life is simpler
144 now.
145
Tim Peters01231392003-01-02 19:10:19 +0000146 today() and now() now round system timestamps to the closest
Tim Petersadf64202003-01-04 06:03:15 +0000147 microsecond <http://www.python.org/sf/661086>. This repairs an
148 irritation most likely seen on Windows systems.
Tim Peters01231392003-01-02 19:10:19 +0000149
Tim Petersf196a0a2003-01-22 04:45:50 +0000150 In dt.astimezone(tz), if tz.utcoffset(dt) returns a duration,
Tim Peters397301e2003-01-02 21:28:08 +0000151 ValueError is raised if tz.dst(dt) returns None (2.3a1 treated it
Tim Petersadf64202003-01-04 06:03:15 +0000152 as 0 instead, but a tzinfo subclass wishing to participate in
153 time zone conversion has to take a stand on whether it supports
154 DST; if you don't care about DST, then code dst() to return 0 minutes,
155 meaning that DST is never in effect).
Tim Peters397301e2003-01-02 21:28:08 +0000156
Tim Peters77023042003-01-03 22:35:24 +0000157 The tzinfo methods utcoffset() and dst() must return a timedelta object
158 (or None) now. In 2.3a1 they could also return an int or long, but that
159 was an unhelpfully redundant leftover from an earlier version wherein
Tim Peters397301e2003-01-02 21:28:08 +0000160 they couldn't return a timedelta. TOOWTDI.
161
Tim Peters77023042003-01-03 22:35:24 +0000162 The example tzinfo class for local time had a bug. It was replaced
163 by a later example coded by Guido.
164
Tim Petersf196a0a2003-01-22 04:45:50 +0000165 datetime.astimezone(tz) no longer raises an exception when the
Tim Petersadf64202003-01-04 06:03:15 +0000166 input datetime has no UTC equivalent in tz. For typical "hybrid" time
167 zones (a single tzinfo subclass modeling both standard and daylight
168 time), this case can arise one hour per year, at the hour daylight time
Tim Petersf196a0a2003-01-22 04:45:50 +0000169 ends. See new docs for details. In short, the new behavior mimics
170 the local wall clock's behavior of repeating an hour in local time.
171
172 dt.astimezone() can no longer be used to convert between naive and aware
173 datetime objects. If you merely want to attach, or remove, a tzinfo
174 object, without any conversion of date and time members, use
175 dt.replace(tzinfo=whatever) instead, where "whatever" is None or a
176 tzinfo subclass instance.
177
178 A new method tzinfo.fromutc(dt) can be overridden in tzinfo subclasses
179 to give complete control over how a UTC time is to be converted to
180 a local time. The default astimezone() implementation calls fromutc()
181 as its last step, so a tzinfo subclass can affect that too by overriding
182 fromutc(). It's expected that the default fromutc() implementation will
183 be suitable as-is for "almost all" time zone subclasses, but the
184 creativity of political time zone fiddling appears unbounded -- fromutc()
185 allows the highly motivated to emulate any scheme expressible in Python.
Tim Petersadf64202003-01-04 06:03:15 +0000186
Tim Peters10cadce2003-01-23 19:58:02 +0000187 datetime.now(): The optional tzinfo argument was undocumented (that's
188 repaired), and its name was changed to tz ("tzinfo" is overloaded enough
189 already). With a tz argument, now(tz) used to return the local date
190 and time, and attach tz to it, without any conversion of date and time
191 members. This was less than useful. Now now(tz) returns the current
192 date and time as local time in tz's time zone, akin to
193 tz.fromutc(datetime.utcnow().replace(tzinfo=utc))
194 where "utc" is an instance of a tzinfo subclass modeling UTC. Without
195 a tz argument, now() continues to return the current local date and time,
196 as a naive datetime object.
197
Tim Peters2a44a8d2003-01-23 20:53:10 +0000198 datetime.fromtimestamp(): Like datetime.now() above, this had less than
199 useful behavior when the optional tinzo argument was specified. See
200 also SF bug report <http://www.python.org/sf/660872>.
201
Tim Peters8d81a012003-01-24 22:36:34 +0000202 date and datetime comparison: In order to prevent comparison from
203 falling back to the default compare-object-addresses strategy, these
204 raised TypeError whenever they didn't understand the other object type.
205 They still do, except when the other object has a "timetuple" attribute,
206 in which case they return NotImplemented now. This gives other
207 datetime objects (e.g., mxDateTime) a chance to intercept the
208 comparison.
209
Tim Peters07534a62003-02-07 22:50:28 +0000210 date, time, datetime and timedelta comparison: When the exception
211 for mixed-type comparisons in the last paragraph doesn't apply, if
212 the comparison is == then False is returned, and if the comparison is
213 != then True is returned. Because dict lookup and the "in" operator
214 only invoke __eq__, this allows, for example,
215
216 if some_datetime in some_sequence:
217 and
218 some_dict[some_timedelta] = whatever
219
220 to work as expected, without raising TypeError just because the
221 sequence is heterogeneous, or the dict has mixed-type keys. [This
222 seems like a good idea to implement for all mixed-type comparisons
223 that don't want to allow falling back to address comparison.]
224
Tim Peters75a6e3b2003-01-04 18:17:36 +0000225 The constructors building a datetime from a timestamp could raise
226 ValueError if the platform C localtime()/gmtime() inserted "leap
227 seconds". Leap seconds are ignored now. On such platforms, it's
228 possible to have timestamps that differ by a second, yet where
229 datetimes constructed from them are equal.
230
Tim Peters506be282003-01-31 22:27:17 +0000231 The pickle format of date, time and datetime objects has changed
232 completely. The undocumented pickler and unpickler functions no
Tim Petersb57f8f02003-02-01 02:54:15 +0000233 longer exist. The undocumented __setstate__() and __getstate__()
234 methods no longer exist either.
Tim Peters506be282003-01-31 22:27:17 +0000235
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000236Library
237-------
238
Andrew MacIntyre251b8162003-02-17 09:20:23 +0000239- the platform dependent path related variables sep, altsep, extsep,
240 pathsep, curdir, pardir and defpath are now defined in the platform
Michael W. Hudson9e5d87f2003-02-17 12:26:23 +0000241 dependent path modules (e.g. ntpath.py) rather than os.py, so these
242 variables are now available via os.path. They continue to be
243 available from the os module.
244 (see <http://www.python.org/sf/680789>).
Andrew MacIntyre251b8162003-02-17 09:20:23 +0000245
Tim Peters6ee04802003-02-05 18:29:34 +0000246- array.array was added to the types repr.py knows about (see
247 <http://www.python.org/sf/680789>).
248
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000249- The new pickletools.py contains lots of documentation about pickle
250 internals, and supplies some helpers for working with pickles, such as
251 a symbolic pickle disassembler.
252
Skip Montanaro9a7c96a2003-01-22 18:17:25 +0000253- Xmlrpclib.py now supports the builtin boolean type.
254
Martin v. Löwis0c6774d2003-01-15 11:51:06 +0000255- py_compile has a new 'doraise' flag and a new PyCompileError
256 exception.
257
Martin v. Löwisd69663d2003-01-15 11:37:23 +0000258- SimpleXMLRPCServer now supports CGI through the CGIXMLRPCRequestHandler
259 class.
260
Guido van Rossum50e92232003-01-14 16:45:04 +0000261- The sets module now raises TypeError in __cmp__, to clarify that
262 sets are not intended to be three-way-compared; the comparison
263 operators are overloaded as subset/superset tests.
264
Guido van Rossumcd0c0472003-01-07 23:03:05 +0000265- Bastion.py and rexec.py are disabled. These modules are not safe in
266 Python 2.2. or 2.3.
267
Neal Norwitzbb0246a2003-01-03 18:12:28 +0000268- realpath is now exported when doing from poxixpath import *.
269 It is also exported for ntpath, macpath, and os2emxpath.
270 See SF bug #659228.
271
Neal Norwitzb9ef4ae2003-01-05 23:19:43 +0000272- New module tarfile from Lars Gustäbel provides a comprehensive interface
273 to tar archive files with transparent gzip and bzip2 compression.
274 See SF patch #651082.
275
Neal Norwitz4f442372003-01-06 06:51:36 +0000276- urlparse can now parse imap:// URLs. See SF feature request #618024.
David Goodgerf349e262003-01-03 03:30:21 +0000277
Neal Norwitze931ed52003-01-10 23:24:32 +0000278- Tkinter.Canvas.scan_dragto() provides an optional parameter to support
279 the gain value which is passed to Tk. SF bug# 602259.
280
Neal Norwitze4c40da2003-01-26 02:45:47 +0000281- Fix logging.handlers.SysLogHandler protocol when using UNIX domain sockets.
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000282 See SF patch #642974.
Neal Norwitze4c40da2003-01-26 02:45:47 +0000283
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000284Tools/Demos
285-----------
286
Skip Montanaro13b29102003-02-03 15:17:25 +0000287- Two new scripts (db2pickle.py and pickle2db.py) were added to the
288 Tools/scripts directory to facilitate conversion from the old bsddb module
289 to the new one. While the user-visible API of the new module is
290 compatible with the old one, it's likely that the version of the
291 underlying database library has changed. To convert from the old library,
292 run the db2pickle.py script using the old version of Python to convert it
293 to a pickle file. After upgrading Python, run the pickle2db.py script
294 using the new version of Python to reconstitute your database. For
295 example:
296
Skip Montanaro621f0552003-02-03 15:48:10 +0000297 % python2.2 db2pickle.py -h some.db > some.pickle
298 % python2.3 pickle2db.py -h some.db.new < some.pickle
Skip Montanaro13b29102003-02-03 15:17:25 +0000299
300 Run the scripts without any args to get a usage message.
301
David Goodgerf349e262003-01-03 03:30:21 +0000302
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000303Build
304-----
305
Guido van Rossum4507ec72003-02-14 19:29:22 +0000306- The audio driver tests (test_ossaudiodev.py and
307 test_linuxaudiodev.py) are no longer run by default. This is
308 because they don't always work, depending on your hardware and
309 software. To run these tests, you must use an invocation like
310 ./python Lib/test/regrtest.py -u audio test_ossaudiodev
311
Skip Montanarodecc6a42003-01-01 20:07:49 +0000312- On systems which build using the configure script, compiler flags which
313 used to be lumped together using the OPT flag have been split into two
314 groups, OPT and BASECFLAGS. OPT is meant to carry just optimization- and
315 debug-related flags like "-g" and "-O3". BASECFLAGS is meant to carry
316 compiler flags that are required to get a clean compile. On some
317 platforms (many Linux flavors in particular) BASECFLAGS will be empty by
318 default. On others, such as Mac OS X and SCO, it will contain required
319 flags. This change allows people building Python to override OPT without
320 fear of clobbering compiler flags which are required to get a clean build.
321
322- On Darwin/Mac OS X platforms, /sw/lib and /sw/include are added to the
323 relevant search lists in setup.py. This allows users building Python to
324 take advantage of the many packages available from the fink project
325 <http://fink.sf.net/>.
326
327- A new Makefile target, scriptsinstall, installs a number of useful scripts
328 from the Tools/scripts directory.
329
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000330C API
331-----
332
Guido van Rossum6297a7a2003-02-19 15:53:17 +0000333- PyEval_GetFrame() is now declared to return a PyFrameObject *
334 instead of a plain PyObject *. (SF patch #686601.)
335
Guido van Rossum6921eca2003-02-18 16:36:28 +0000336- PyNumber_Check() now checks that the object has a nb_int or nb_float
337 slot, rather than simply checking whether it has a non-NULL
338 tp_as_number pointer.
339
Guido van Rossumeea47182003-02-11 20:39:59 +0000340- A C type that inherits from a base type that defines tp_as_buffer
341 will now inherit the tp_as_buffer pointer if it doesn't define one.
342 (SF #681367)
343
Neil Schemenauer5042da62003-02-04 20:59:40 +0000344- The PyArg_Parse functions now issue a DeprecationWarning if a float
345 argument is provided when an integer is specified (this affects the 'b',
346 'B', 'h', 'H', 'i', and 'l' codes). Future versions of Python will
347 raise a TypeError.
Neil Schemenauercd63e612003-01-24 22:15:53 +0000348
David Goodgerf349e262003-01-03 03:30:21 +0000349
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000350New platforms
351-------------
352
David Goodgerf349e262003-01-03 03:30:21 +0000353TBD
354
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000355Tests
356-----
357
David Goodgerf349e262003-01-03 03:30:21 +0000358TBD
359
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000360Windows
361-------
362
Thomas Hellerdda583d2003-01-31 20:45:41 +0000363- distutils' msvccompiler class now passes the preprocessor options to
364 the resource compiler. See SF patch #669198.
365
Tim Peters00640262003-01-24 15:31:31 +0000366- The bsddb module now ships with Sleepycat's 4.1.25.NC, the latest
367 release without strong cryptography.
368
Thomas Heller6c64fa72003-01-08 15:14:55 +0000369- sys.path[0], if it contains a directory name, is now always an
370 absolute pathname.
371
Tim Petersbbc5d162003-01-02 16:02:27 +0000372- The new logging package is now installed by the Windows installer. It
373 wasn't in 2.3a1 due to oversight.
374
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000375Mac
376---
377
Jack Jansen1a1b6e42003-01-27 15:21:39 +0000378- There are new dialogs EasyDialogs.AskFileForOpen, AskFileForSave
379 and AskFolder. The old macfs.StandardGetFile and friends are deprecated.
Tim Peters07534a62003-02-07 22:50:28 +0000380
Jack Jansenc9296362003-02-06 23:10:45 +0000381- Most of the standard library now uses pathnames or FSRefs in preference
382 of FSSpecs, and use the underlying Carbon.File and Carbon.Folder modules
383 in stead of macfs. macfs will probably be deprecated in the future.
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000384
Jack Jansen1a1b6e42003-01-27 15:21:39 +0000385- Type Carbon.File.FSCatalogInfo and supporting methods have been implemented.
386 This also makes macfs.FSSpec.SetDates() work again.
Jack Jansen9f70aab2003-02-16 23:00:53 +0000387
388- There is a new module pimp, the package install manager for Python, and
389 accompanying applet PackageManager. These allow you to easily download
390 and install pretested extension packages either in source or binary
391 form. Only in MacPython-OSX.
392
393- Applets are now built with bundlebuilder in MacPython-OSX, which should make
Jack Jansen5d44b342003-02-18 23:32:47 +0000394 them more robust and also provides a path towards BuildApplication. The
395 downside of this change is that applets can no longer be run from the
396 Terminal window, this will hopefully be fixed in the 2.3b1.
David Goodgerf349e262003-01-03 03:30:21 +0000397
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000398
Tim Petersaf8446f2001-12-21 21:36:50 +0000399What's New in Python 2.3 alpha 1?
Tim Petersaf8446f2001-12-21 21:36:50 +0000400=================================
401
Guido van Rossumae548862002-12-31 15:47:36 +0000402*Release date: 31-Dec-2002*
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000403
Tim Petersaf8446f2001-12-21 21:36:50 +0000404Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000405--------------------------------------------
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000406
Michael W. Hudson96bc3b42002-11-26 14:48:23 +0000407- One can now assign to __bases__ and __name__ of new-style classes.
408
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000409- dict() now accepts keyword arguments so that dict(one=1, two=2)
410 is the equivalent of {"one": 1, "two": 2}. Accordingly,
Just van Rossuma797d812002-11-23 09:45:04 +0000411 the existing (but undocumented) 'items' keyword argument has
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000412 been eliminated. This means that dict(items=someMapping) now has
Just van Rossuma797d812002-11-23 09:45:04 +0000413 a different meaning than before.
414
Walter Dörwaldf1715402002-11-19 20:49:15 +0000415- int() now returns a long object if the argument is outside the
David Goodgerf349e262003-01-03 03:30:21 +0000416 integer range, so int("4" * 1000), int(1e200) and int(1L<<1000) will
Walter Dörwaldf1715402002-11-19 20:49:15 +0000417 all return long objects instead of raising an OverflowError.
Tim Petersaf8446f2001-12-21 21:36:50 +0000418
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000419- Assignment to __class__ is disallowed if either the old or the new
Guido van Rossume3438782002-08-12 03:42:03 +0000420 class is a statically allocated type object (such as defined by an
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000421 extension module). This prevents anomalies like 2.__class__ = bool.
Guido van Rossume3438782002-08-12 03:42:03 +0000422
423- New-style object creation and deallocation have been sped up
424 significantly; they are now faster than classic instance creation
425 and deallocation.
426
427- The __slots__ variable can now mention "private" names, and the
428 right thing will happen (e.g. __slots__ = ["__foo"]).
429
430- The built-ins slice() and buffer() are now callable types. The
431 types classobj (formerly class), code, function, instance, and
432 instancemethod (formerly instance-method), which have no built-in
433 names but are accessible through the types module, are now also
434 callable. The type dict-proxy is renamed to dictproxy.
435
436- Cycles going through the __class__ link of a new-style instance are
437 now detected by the garbage collector.
438
439- Classes using __slots__ are now properly garbage collected.
440 [SF bug 519621]
441
442- Tightened the __slots__ rules: a slot name must be a valid Python
443 identifier.
444
445- The constructor for the module type now requires a name argument and
446 takes an optional docstring argument. Previously, this constructor
447 ignored its arguments. As a consequence, deriving a class from a
448 module (not from the module type) is now illegal; previously this
449 created an unnamed module, just like invoking the module type did.
450 [SF bug 563060]
451
452- A new type object, 'basestring', is added. This is a common base type
453 for 'str' and 'unicode', and can be used instead of
454 types.StringTypes, e.g. to test whether something is "a string":
455 isinstance(x, basestring) is True for Unicode and 8-bit strings. This
456 is an abstract base class and cannot be instantiated directly.
457
458- Changed new-style class instantiation so that when C's __new__
459 method returns something that's not a C instance, its __init__ is
460 not called. [SF bug #537450]
461
462- Fixed super() to work correctly with class methods. [SF bug #535444]
463
464- If you try to pickle an instance of a class that has __slots__ but
465 doesn't define or override __getstate__, a TypeError is now raised.
466 This is done by adding a bozo __getstate__ to the class that always
467 raises TypeError. (Before, this would appear to be pickled, but the
468 state of the slots would be lost.)
469
Tim Petersaf8446f2001-12-21 21:36:50 +0000470Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000471-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000472
Guido van Rossuma3b89532002-12-30 22:59:32 +0000473- Import from zipfiles is now supported. The name of a zipfile placed
Just van Rossum01875eb2002-12-31 10:22:38 +0000474 on sys.path causes the import statement to look for importable Python
475 modules (with .py, pyc and .pyo extensions) and packages inside the
476 zipfile. The zipfile import follows the specification (though not
477 the sample implementation) of PEP 273. The semantics of __path__ are
Guido van Rossuma3b89532002-12-30 22:59:32 +0000478 compatible with those that have been implemented in Jython since
479 Jython 2.1.
480
Just van Rossum01875eb2002-12-31 10:22:38 +0000481- PEP 302 has been accepted. Although it was inititally developed to
Tim Petersbbc5d162003-01-02 16:02:27 +0000482 support zipimport, it offers a new, general import hook mechanism.
Just van Rossum01875eb2002-12-31 10:22:38 +0000483 Several new variables have been added to the sys module:
484 sys.meta_path, sys.path_hooks, and sys.path_importer_cache; these
485 make extending the import statement much more convenient than
486 overriding the __import__ built-in function. For a description of
487 these, see PEP 302.
488
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000489- A frame object's f_lineno attribute can now be written to from a
490 trace function to change which line will execute next. A command to
491 exploit this from pdb has been added. [SF patch #643835]
492
Marc-André Lemburg20b91352002-12-12 18:01:43 +0000493- The _codecs support module for codecs.py was turned into a builtin
494 module to assure that at least the builtin codecs are available
495 to the Python parser for source code decoding according to PEP 263.
496
Walter Dörwaldd9a6ad32002-12-12 16:41:44 +0000497- issubclass now supports a tuple as the second argument, just like
498 isinstance does. ``issubclass(X, (A, B))`` is equivalent to
499 ``issubclass(X, A) or issubclass(X, B)``.
500
Tim Petersb9099c32002-11-12 22:08:10 +0000501- Thanks to Armin Rigo, the last known way to provoke a system crash
502 by cleverly arranging for a comparison function to mutate a list
503 during a list.sort() operation has been fixed. The effect of
504 attempting to mutate a list, or even to inspect its contents or
505 length, while a sort is in progress, is not defined by the language.
506 The C implementation of Python 2.3 attempts to detect mutations,
507 and raise ValueError if one occurs, but there's no guarantee that
508 all mutations will be caught, or that any will be caught across
509 releases or implementations.
510
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000511- Unicode file name processing for Windows (PEP 277) is implemented.
Mark Hammond8696ebc2002-10-08 02:44:31 +0000512 All platforms now have an os.path.supports_unicode_filenames attribute,
513 which is set to True on Windows NT/2000/XP, and False elsewhere.
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000514
Walter Dörwald3aeb6322002-09-02 13:14:32 +0000515- Codec error handling callbacks (PEP 293) are implemented.
516 Error handling in unicode.encode or str.decode can now be customized.
517
Guido van Rossum45ec02a2002-08-19 21:43:18 +0000518- A subtle change to the semantics of the built-in function intern():
519 interned strings are no longer immortal. You must keep a reference
520 to the return value intern() around to get the benefit.
521
Guido van Rossumf808b892002-08-16 03:38:10 +0000522- Use of 'None' as a variable, argument or attribute name now
523 issues a SyntaxWarning. In the future, None may become a keyword.
524
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000525- SET_LINENO is gone. co_lnotab is now consulted to determine when to
526 call the trace function. C code that accessed f_lineno should call
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000527 PyCode_Addr2Line instead (f_lineno is still there, but only kept up
528 to date when there is a trace function set).
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000529
Guido van Rossum9be89462002-08-14 16:11:30 +0000530- There's a new warning category, FutureWarning. This is used to warn
531 about a number of situations where the value or sign of an integer
532 result will change in Python 2.4 as a result of PEP 237 (integer
533 unification). The warnings implement stage B0 mentioned in that
534 PEP. The warnings are about the following situations:
535
536 - Octal and hex literals without 'L' prefix in the inclusive range
537 [0x80000000..0xffffffff]; these are currently negative ints, but
538 in Python 2.4 they will be positive longs with the same bit
539 pattern.
540
541 - Left shifts on integer values that cause the outcome to lose
542 bits or have a different sign than the left operand. To be
543 precise: x<<n where this currently doesn't yield the same value
544 as long(x)<<n; in Python 2.4, the outcome will be long(x)<<n.
545
546 - Conversions from ints to string that show negative values as
547 unsigned ints in the inclusive range [0x80000000..0xffffffff];
548 this affects the functions hex() and oct(), and the string
549 formatting codes %u, %o, %x, and %X. In Python 2.4, these will
550 show signed values (e.g. hex(-1) currently returns "0xffffffff";
551 in Python 2.4 it will return "-0x1").
552
Guido van Rossum9a2eda52002-12-31 02:12:42 +0000553- The bits manipulated under the cover by sys.setcheckinterval() have
554 been changed. Both the check interval and the ticker used to be
555 per-thread values. They are now just a pair of global variables.
556 In addition, the default check interval was boosted from 10 to 100
557 bytecode instructions. This may have some effect on systems that
558 relied on the old default value. In particular, in multi-threaded
559 applications which try to be highly responsive, response time will
560 increase by some (perhaps imperceptible) amount.
Skip Montanaro979c74b2002-09-03 21:25:14 +0000561
Tim Petersd64c1de2002-08-12 17:36:03 +0000562- When multiplying very large integers, a version of the so-called
563 Karatsuba algorithm is now used. This is most effective if the
564 inputs have roughly the same size. If they both have about N digits,
565 Karatsuba multiplication has O(N**1.58) runtime (the exponent is
566 log_base_2(3)) instead of the previous O(N**2). Measured results may
Tim Peters012c0a32002-08-16 03:40:07 +0000567 be better or worse than that, depending on platform quirks. Besides
568 the O() improvement in raw instruction count, the Karatsuba algorithm
569 appears to have much better cache behavior on extremely large integers
570 (starting in the ballpark of a million bits). Note that this is a
571 simple implementation, and there's no intent here to compete with,
572 e.g., GMP. It gives a very nice speedup when it applies, but a package
573 devoted to fast large-integer arithmetic should run circles around it.
Tim Peters5af4e6c2002-08-12 02:31:19 +0000574
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000575- u'%c' will now raise a ValueError in case the argument is an
576 integer outside the valid range of Unicode code point ordinals.
577
Guido van Rossumdeb09362002-08-09 17:16:30 +0000578- The tempfile module has been overhauled for enhanced security. The
579 mktemp() function is now deprecated; new, safe replacements are
580 mkstemp() (for files) and mkdtemp() (for directories), and the
581 higher-level functions NamedTemporaryFile() and TemporaryFile().
582 Use of some global variables in this module is also deprecated; the
583 new functions have keyword arguments to provide the same
584 functionality. All Lib, Tools and Demo modules that used the unsafe
585 interfaces have been updated to use the safe replacements. Thanks
586 to Zack Weinberg!
587
Guido van Rossumd81a9832002-08-09 15:57:34 +0000588- When x is an object whose class implements __mul__ and __rmul__,
589 1.0*x would correctly invoke __rmul__, but 1*x would erroneously
590 invoke __mul__. This was due to the sequence-repeat code in the int
591 type. This has been fixed now.
592
Barry Warsawd79f6832002-08-06 17:01:51 +0000593- Previously, "str1 in str2" required str1 to be a string of length 1.
594 This restriction has been relaxed to allow str1 to be a string of
595 any length. Thus "'el' in 'hello world'" returns True now.
596
Guido van Rossumb57089c2002-08-06 16:20:26 +0000597- File objects are now their own iterators. For a file f, iter(f) now
598 returns f (unless f is closed), and f.next() is similar to
599 f.readline() when EOF is not reached; however, f.next() uses a
600 readahead buffer that messes up the file position, so mixing
601 f.next() and f.readline() (or other methods) doesn't work right.
602 Calling f.seek() drops the readahead buffer, but other operations
603 don't. It so happens that this gives a nice additional speed boost
604 to "for line in file:"; the xreadlines method and corresponding
Guido van Rossumbffb2ef2002-08-09 17:17:07 +0000605 module are now obsolete. Thanks to Oren Tirosh!
Guido van Rossumb57089c2002-08-06 16:20:26 +0000606
Guido van Rossumde392d32002-08-05 14:17:20 +0000607- Encoding declarations (PEP 263, phase 1) have been implemented. A
608 comment of the form "# -*- coding: <encodingname> -*-" in the first
609 or second line of a Python source file indicates the encoding.
Martin v. Löwis00f1e3f2002-08-04 17:29:52 +0000610
Tim Petersf47630f2002-08-01 02:34:51 +0000611- list.sort() has a new implementation. While cross-platform results
612 may vary, and in data-dependent ways, this is much faster on many
613 kinds of partially ordered lists than the previous implementation,
614 and reported to be just as fast on randomly ordered lists on
615 several major platforms. This sort is also stable (if A==B and A
616 precedes B in the list at the start, A precedes B after the sort too),
617 although the language definition does not guarantee stability. A
618 potential drawback is that list.sort() may require temp space of
Skip Montanaroa2a07bc2002-09-30 15:23:01 +0000619 len(list)*2 bytes (``*4`` on a 64-bit machine). It's therefore possible
Tim Petersf47630f2002-08-01 02:34:51 +0000620 for list.sort() to raise MemoryError now, even if a comparison function
621 does not. See <http://www.python.org/sf/587076> for full details.
622
Guido van Rossum2d5389c2002-07-23 03:44:35 +0000623- All standard iterators now ensure that, once StopIteration has been
624 raised, all future calls to next() on the same iterator will also
625 raise StopIteration. There used to be various counterexamples to
626 this behavior, which could caused confusion or subtle program
627 breakage, without any benefits. (Note that this is still an
628 iterator's responsibility; the iterator framework does not enforce
629 this.)
630
Mark Hammondc0e35152002-07-16 01:32:30 +0000631- Ctrl+C handling on Windows has been made more consistent with
632 other platforms. KeyboardInterrupt can now reliably be caught,
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000633 and Ctrl+C at an interactive prompt no longer terminates the
Mark Hammondc0e35152002-07-16 01:32:30 +0000634 process under NT/2k/XP (it never did under Win9x). Ctrl+C will
Tim Peters5af4e6c2002-08-12 02:31:19 +0000635 interrupt time.sleep() in the main thread, and any child processes
636 created via the popen family (on win2k; we can't make win9x work
Mark Hammond8f3afc72002-08-10 06:26:31 +0000637 reliably) are also interrupted (as generally happens on for Linux/Unix.)
638 [SF bugs 231273, 439992 and 581232]
Mark Hammondc0e35152002-07-16 01:32:30 +0000639
Mark Hammond8696ebc2002-10-08 02:44:31 +0000640- sys.getwindowsversion() has been added on Windows. This
641 returns a tuple with information about the version of Windows
642 currently running.
643
Raymond Hettinger5a04aec2002-06-25 00:25:30 +0000644- Slices and repetitions of buffer objects now consistently return
645 a string. Formerly, strings would be returned most of the time,
646 but a buffer object would be returned when the repetition count
647 was one or when the slice range was all inclusive.
648
Walter Dörwald3430d702002-06-17 10:43:59 +0000649- Unicode objects in sys.path are no longer ignored but treated
650 as directory names.
651
Neal Norwitz1f68fc72002-06-14 00:50:42 +0000652- Fixed string.startswith and string.endswith builtin methods
653 so they accept negative indices. [SF bug 493951]
654
Guido van Rossumc5fe5eb2002-06-12 03:45:21 +0000655- Fixed a bug with a continue inside a try block and a yield in the
656 finally clause. [SF bug 567538]
657
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000658- Most builtin sequences now support "extended slices", i.e. slices
Guido van Rossum2e82e712002-06-13 11:41:07 +0000659 with a third "stride" parameter. For example, "hello world"[::-1]
660 gives "dlrow olleh".
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000661
Neal Norwitzd68f5172002-05-29 15:54:55 +0000662- A new warning PendingDeprecationWarning was added to provide
663 direction on features which are in the process of being deprecated.
664 The warning will not be printed by default. To see the pending
665 deprecations, use -Walways::PendingDeprecationWarning::
666 as a command line option or warnings.filterwarnings() in code.
667
Fred Draked0ba6362002-05-02 21:28:26 +0000668- Deprecated features of xrange objects have been removed as
669 promised. The start, stop, and step attributes and the tolist()
670 method no longer exist. xrange repetition and slicing have been
671 removed.
672
Guido van Rossum7dab2422002-04-26 19:40:56 +0000673- New builtin function enumerate(x), from PEP 279. Example:
674 enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
675 The argument can be an arbitrary iterable object.
676
Neil Schemenauer89e3ee02002-04-26 01:58:53 +0000677- The assert statement no longer tests __debug__ at runtime. This means
678 that assert statements cannot be disabled by assigning a false value
679 to __debug__.
680
Walter Dörwald068325e2002-04-15 13:36:47 +0000681- A method zfill() was added to str and unicode, that fills a numeric
682 string to the left with zeros. For example,
683 "+123".zfill(6) -> "+00123".
684
Guido van Rossum862fe3c2002-04-15 12:36:47 +0000685- Complex numbers supported divmod() and the // and % operators, but
686 these make no sense. Since this was documented, they're being
687 deprecated now.
688
Guido van Rossum26dd8302002-04-26 20:11:29 +0000689- String and unicode methods lstrip(), rstrip() and strip() now take
690 an optional argument that specifies the characters to strip. For
691 example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
Guido van Rossum49042042002-04-13 00:59:05 +0000692
Guido van Rossumc0d3f4e2002-11-27 13:10:40 +0000693- There's a new dictionary constructor (a class method of the dict
694 class), dict.fromkeys(iterable, value=None). It constructs a
695 dictionary with keys taken from the iterable and all values set to a
696 single value. It can be used for building sets and for removing
697 duplicates from sequences.
Raymond Hettingere33d3df2002-11-27 07:29:33 +0000698
Guido van Rossumc69343b2002-04-12 19:22:48 +0000699- Added a new dict method pop(key). This removes and returns the
700 value corresponding to key. [SF patch #539949]
701
Guido van Rossum47834462002-04-04 15:21:33 +0000702- A new built-in type, bool, has been added, as well as built-in
703 names for its two values, True and False. Comparisons and sundry
704 other operations that return a truth value have been changed to
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000705 return a bool instead. Read PEP 285 for an explanation of why this
Guido van Rossum47834462002-04-04 15:21:33 +0000706 is backward compatible.
707
Guido van Rossum95b62a62002-03-29 01:07:24 +0000708- Fixed two bugs reported as SF #535905: under certain conditions,
709 deallocating a deeply nested structure could cause a segfault in the
710 garbage collector, due to interaction with the "trashcan" code;
711 access to the current frame during destruction of a local variable
712 could access a pointer to freed memory.
713
Guido van Rossumfe0ca4a2002-06-18 21:20:13 +0000714- The optional object allocator ("pymalloc") has been enabled by
715 default. The recommended practice for memory allocation and
716 deallocation has been streamlined. A header file is included,
717 Misc/pymemcompat.h, which can be bundled with 3rd party extensions
718 and lets them use the same API with Python versions from 1.5.2
719 onwards.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000720
Martin v. Löwiscfeb3b62002-03-03 21:30:27 +0000721- PyErr_Display will provide file and line information for all exceptions
722 that have an attribute print_file_and_line, not just SyntaxErrors.
723
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000724- The UTF-8 codec will now encode and decode Unicode surrogates
725 correctly and without raising exceptions for unpaired ones.
726
Guido van Rossumadd88062002-08-15 14:01:14 +0000727- Universal newlines (PEP 278) is implemented. Briefly, using 'U'
728 instead of 'r' when opening a text file for reading changes the line
729 ending convention so that any of '\r', '\r\n', and '\n' is
730 recognized (even mixed in one file); all three are converted to
731 '\n', the standard Python line end character.
732
Neal Norwitz649b7592002-01-01 19:07:13 +0000733- file.xreadlines() now raises a ValueError if the file is closed:
734 Previously, an xreadlines object was returned which would raise
735 a ValueError when the xreadlines.next() method was called.
736
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000737- sys.exit() inadvertently allowed more than one argument.
Neal Norwitz0c766a02002-03-27 13:03:09 +0000738 An exception will now be raised if more than one argument is used.
739
Gustavo Niemeyer17c5a332002-12-16 14:09:22 +0000740- Changed evaluation order of dictionary literals to conform to the
741 general left to right evaluation order rule. Now {f1(): f2()} will
742 evaluate f1 first.
Gustavo Niemeyer78429a62002-12-16 13:54:02 +0000743
Gustavo Niemeyer786ddb22002-12-16 18:12:53 +0000744- Fixed bug #521782: when a file was in non-blocking mode, file.read()
745 could silently lose data or wrongly throw an unknown error.
746
Neil Schemenauerb983aa02002-12-30 20:22:23 +0000747- The sq_repeat, sq_inplace_repeat, sq_concat and sq_inplace_concat
748 slots are now always tried after trying the corresponding nb_* slots.
749 This fixes a number of minor bugs (see bug #624807).
750
Neal Norwitz74a032e2003-01-10 23:29:48 +0000751- Fix problem with dynamic loading on 64-bit AIX (see bug #639945).
752
Tim Petersaf8446f2001-12-21 21:36:50 +0000753Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000754-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000755
Raymond Hettinger9543b342003-01-18 23:22:20 +0000756- Added three operators to the operator module:
757 operator.pow(a,b) which is equivalent to: a**b.
758 operator.is_(a,b) which is equivalent to: a is b.
759 operator.is_not(a,b) which is equivalent to: a is not b.
760
Martin v. Löwis24a880b2002-12-31 12:55:15 +0000761- posix.openpty now works on all systems that have /dev/ptmx.
762
Guido van Rossuma3b89532002-12-30 22:59:32 +0000763- A module zipimport exists to support importing code from zip
764 archives.
765
Tim Peterse820cb62002-12-16 20:57:22 +0000766- The new datetime module supplies classes for manipulating dates and
767 times. The basic design came from the Zope "fishbowl process", and
768 favors practical commercial applications over calendar esoterica. See
769
770 http://www.zope.org/Members/fdrake/DateTimeWiki/FrontPage
771
Martin v. Löwisffad6332002-11-26 09:28:05 +0000772- _tkinter now returns Tcl objects, instead of strings. Objects which
773 have Python equivalents are converted to Python objects, other objects
774 are wrapped. This can be configured through the wantobjects method,
Martin v. Löwis8c8aa5d2002-11-26 21:39:48 +0000775 or Tkinter.wantobjects.
Martin v. Löwisffad6332002-11-26 09:28:05 +0000776
Barry Warsawc27f4bd2002-12-30 21:03:26 +0000777- The PyBSDDB wrapper around the Sleepycat Berkeley DB library has
778 been added as the package bsddb. The traditional bsddb module is
779 still available in source code, but not built automatically anymore,
780 and is now named bsddb185. This supports Berkeley DB versions from
Skip Montanaro13b29102003-02-03 15:17:25 +0000781 3.0 to 4.1. For help converting your databases from the old module (which
782 probably used an obsolete version of Berkeley DB) to the new module, see
783 the db2pickle.py and pickle2db.py scripts described in the Tools/Demos
784 section above.
Martin v. Löwisef546b32002-11-19 08:12:57 +0000785
Martin v. Löwis677bde22002-11-23 22:08:15 +0000786- unicodedata was updated to Unicode 3.2. It supports normalization
787 and names for Hangul syllables and CJK unified ideographs.
Martin v. Löwis7d41e292002-11-23 12:22:32 +0000788
Neal Norwitz94a83fd2002-11-02 17:46:24 +0000789- resource.getrlimit() now returns longs instead of ints.
790
Martin v. Löwis080689c2002-10-26 14:42:02 +0000791- readline now dynamically adjusts its input/output stream if
792 sys.stdin/stdout changes.
793
Guido van Rossumba602972002-10-01 18:18:58 +0000794- The _tkinter module (and hence Tkinter) has dropped support for
795 Tcl/Tk 8.0 and 8.1. Only Tcl/Tk versions 8.2, 8.3 and 8.4 are
796 supported.
797
Martin v. Löwis658009a2002-09-16 17:26:24 +0000798- cPickle.BadPickleGet is now a class.
799
Martin v. Löwisa19bfe02002-10-16 18:28:36 +0000800- The time stamps in os.stat_result are floating point numbers
801 after stat_float_times has been called.
Martin v. Löwis94717ed2002-09-09 14:24:16 +0000802
Neal Norwitzb5673922002-09-05 21:48:07 +0000803- If the size passed to mmap.mmap() is larger than the length of the
804 file on non-Windows platforms, a ValueError is raised. [SF bug 585792]
805
Guido van Rossumb57089c2002-08-06 16:20:26 +0000806- The xreadlines module is slated for obsolescence.
807
Guido van Rossum79f0a102002-07-23 03:32:08 +0000808- The strptime function in the time module is now always available (a
809 Python implementation is used when the C library doesn't define it).
810
Guido van Rossum9562bcf2002-06-14 21:31:18 +0000811- The 'new' module is no longer an extension, but a Python module that
812 only exists for backwards compatibility. Its contents are no longer
813 functions but callable type objects.
814
Tim Peters81b92512002-04-29 01:37:32 +0000815- The bsddb.*open functions can now take 'None' as a filename.
Anthony Baxter83888952002-04-23 02:11:05 +0000816 This will create a temporary in-memory bsddb that won't be
Tim Peters81b92512002-04-29 01:37:32 +0000817 written to disk.
Anthony Baxter83888952002-04-23 02:11:05 +0000818
Martin v. Löwisb96152c2002-12-31 13:20:15 +0000819- posix.getloadavg, posix.lchown, posix.killpg, posix.mknod, and
820 posix.getpgid have been added where available.
Martin v. Löwis06a83e92002-04-14 10:19:44 +0000821
Martin v. Löwisf0a46682002-11-03 17:20:12 +0000822- The locale module now exposes the C library's gettext interface. It
823 also has a new function getpreferredencoding.
Martin v. Löwis2e64c342002-03-27 18:49:02 +0000824
Tim Petersfbf74f22002-03-14 19:06:01 +0000825- A security hole ("double free") was found in zlib-1.1.3, a popular
826 third party compression library used by some Python modules. The
827 hole was quickly plugged in zlib-1.1.4, and the Windows build of
828 Python now ships with zlib-1.1.4.
829
Martin v. Löwis688357e2002-04-08 21:28:20 +0000830- pwd, grp, and resource return enhanced tuples now, with symbolic
831 field names.
Martin v. Löwis29001ff2002-03-01 10:47:37 +0000832
Martin v. Löwis99866332002-03-01 10:27:01 +0000833- array.array is now a type object. A new format character
834 'u' indicates Py_UNICODE arrays. For those, .tounicode and
835 .fromunicode methods are available. Arrays now support __iadd__
836 and __imul__.
837
Neal Norwitze790eae2002-01-01 21:14:12 +0000838- dl now builds on every system that has dlfcn.h. Failure in case
Martin v. Löwis93227272002-01-01 20:18:30 +0000839 of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
840 is called.
841
Michael W. Hudson34f20ea2002-05-27 15:08:24 +0000842- signal.sigpending, signal.sigprocmask and signal.sigsuspend have
843 been added where available.
844
Skip Montanaro8e790e72002-09-03 13:25:17 +0000845- The sys module acquired a new attribute, api_version, which evaluates
846 to the value of the PYTHON_API_VERSION macro with which the
847 interpreter was compiled.
848
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000849- Fixed bug #470582: sre module would return a tuple (None, 'a', 'ab')
850 when applying the regular expression '^((a)c)?(ab)$' on 'ab'. It now
851 returns (None, None, 'ab'), as expected. Also fixed handling of
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +0000852 lastindex/lastgroup match attributes in similar cases. For example,
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000853 when running the expression r'(a)(b)?b' over 'ab', lastindex must be
854 1, not 2.
855
Gustavo Niemeyerc523b042002-11-07 03:28:56 +0000856- Fixed bug #581080: sre scanner was not checking the buffer limit
857 before increasing the current pointer. This was creating an infinite
858 loop in the search function, once the pointer exceeded the buffer
859 limit.
860
Thomas Heller95cb7e42002-11-07 16:23:55 +0000861- The os.fdopen function now enforces a file mode starting with the
862 letter 'r', 'w' or 'a', otherwise a ValueError is raised. This fixes
863 bug #623464.
864
Greg Ward6c58d462003-01-03 18:02:15 +0000865- The linuxaudiodev module is now deprecated; it is being replaced by
866 ossaudiodev. The interface has been extended to cover a lot more of
867 OSS (see www.opensound.com), including most DSP ioctls and the
868 OSS mixer API. Documentation forthcoming in 2.3a2.
869
Tim Petersaf8446f2001-12-21 21:36:50 +0000870Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000871-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000872
Guido van Rossum747f8062003-01-03 16:33:49 +0000873- imaplib.py now supports SSL (Tino Lange and Piers Lauder).
874
Just van Rossum5e156ad2002-12-31 16:38:01 +0000875- Freeze's modulefinder.py has been moved to the standard library;
876 slightly improved so it will issue less false missing submodule
877 reports (see sf path #643711 for details). Documentation will follow
878 with Python 2.3a2.
879
Martin v. Löwis96a60e42002-12-31 13:11:54 +0000880- os.path exposes getctime.
881
Raymond Hettingeraf72d522002-12-29 20:14:11 +0000882- unittest.py now has two additional methods called assertAlmostEqual()
883 and failIfAlmostEqual(). They implement an approximate comparision
884 by rounding the difference between the two arguments and comparing
885 the result to zero. Approximate comparision is essential for
886 unit tests of floating point results.
887
Raymond Hettingere11b5102002-12-25 16:37:19 +0000888- calendar.py now depends on the new datetime module rather than
889 the time module. As a result, the range of allowable dates
890 has been increased.
891
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000892- pdb has a new 'j(ump)' command to select the next line to be
893 executed.
894
Thomas Heller1b3b49d2002-12-12 19:13:44 +0000895- The distutils created windows installers now can run a
896 postinstallation script.
897
Martin v. Löwis4581cfa2002-11-22 08:23:09 +0000898- doctest.testmod can now be called without argument, which means to
899 test the current module.
900
Martin v. Löwisf86e8ef2002-11-22 08:08:44 +0000901- When cancelling a server that implemented threading with a keyboard
902 interrupt, the server would shut down but not terminate (waiting on
903 client threads). A new member variable, daemon_threads, was added to
904 the ThreadingMixIn class in SocketServer.py to make it explicit that
905 this behavior needs to be controlled.
906
Guido van Rossum545c2502002-11-15 13:19:58 +0000907- A new module, optparse, provides a fancy alternative to getopt for
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000908 command line parsing. It is a slightly modified version of Greg
Guido van Rossum545c2502002-11-15 13:19:58 +0000909 Ward's Optik package.
910
Raymond Hettinger79947162002-11-15 06:46:14 +0000911- UserDict.py now defines a DictMixin class which defines all dictionary
912 methods for classes that already have a minimum mapping interface.
913 This greatly simplifies writing classes that need to be substitutable
914 for dictionaries (such as the shelve module).
915
916- shelve.py now subclasses from UserDict.DictMixin. Now shelve supports
917 all dictionary methods. This eases the transition to persistent
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000918 storage for scripts originally written with dictionaries in mind.
Raymond Hettinger79947162002-11-15 06:46:14 +0000919
Skip Montanaro3bf99e32002-12-08 18:36:24 +0000920- shelve.open and the various classes in shelve.py now accept an optional
921 binary flag, which defaults to False. If True, the values stored in the
922 shelf are binary pickles.
923
Guido van Rossumfda06742002-11-13 16:29:18 +0000924- A new package, logging, implements the logging API defined by PEP
925 282. The code is written by Vinay Sajip.
926
Walter Dörwald4dbf1922002-11-06 16:53:44 +0000927- StreamReader, StreamReaderWriter and StreamRecoder in the codecs
928 modules are iterators now.
929
Tim Peters9288f952002-11-05 20:38:55 +0000930- gzip.py now handles files exceeding 2GB. Files over 4GB also work
931 now (provided the OS supports it, and Python is configured with large
932 file support), but in that case the underlying gzip file format can
933 record only the least-significant 32 bits of the file size, so that
934 some tools working with gzipped files may report an incorrect file
935 size.
Tim Petersfb0ea522002-11-04 19:50:11 +0000936
Martin v. Löwis74b51ac2002-10-26 14:50:45 +0000937- xml.sax.saxutils.unescape has been added, to replace entity references
938 with their entity value.
939
Martin v. Löwis77ac4292002-10-15 15:11:13 +0000940- Queue.Queue.{put,get} now support an optional timeout argument.
941
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000942- Various features of Tk 8.4 are exposed in Tkinter.py. The multiple
943 option of tkFileDialog is exposed as function askopenfile{,name}s.
Martin v. Löwis2ec36272002-10-13 10:22:08 +0000944
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000945- Various configure methods of Tkinter have been stream-lined, so that
946 tag_configure, image_configure, window_configure now return a
Tim Petersfb0ea522002-11-04 19:50:11 +0000947 dictionary when invoked with no argument.
Martin v. Löwis6ce13152002-10-10 14:36:13 +0000948
Guido van Rossum2b492b62002-10-09 21:40:48 +0000949- Importing the readline module now no longer has the side effect of
950 calling setlocale(LC_CTYPE, ""). The initial "C" locale, or
951 whatever locale is explicitly set by the user, is preserved. If you
952 want repr() of 8-bit strings in your preferred encoding to preserve
953 all printable characters of that encoding, you have to add the
954 following code to your $PYTHONSTARTUP file or to your application's
955 main():
956
957 import locale
958 locale.setlocale(locale.LC_CTYPE, "")
959
Martin v. Löwise9ce0b02002-10-07 13:23:24 +0000960- shutil.move was added. shutil.copytree now reports errors as an
961 exception at the end, instead of printing error messages.
962
Marc-André Lemburg97047e22002-10-04 11:55:21 +0000963- Encoding name normalization was generalized to not only
964 replace hyphens with underscores, but also all other non-alphanumeric
965 characters (with the exception of the dot which is used for Python
966 package names during lookup). The aliases.py mapping was updated
967 to the new standard.
968
Walter Dörwald5ccaf8f2002-09-06 16:15:58 +0000969- mimetypes has two new functions: guess_all_extensions() which
970 returns a list of all known extensions for a mime type, and
971 add_type() which adds one mapping between a mime type and
972 an extension to the database.
973
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000974- New module: sets, defines the class Set that implements a mutable
975 set type using the keys of a dict to represent the set. There's
976 also a class ImmutableSet which is useful when you need sets of sets
977 or when you need to use sets as dict keys, and a class BaseSet which
Raymond Hettingeref8b9c62002-12-09 08:56:06 +0000978 is the base class of the two.
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000979
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000980- Added random.sample(population,k) for random sampling without replacement.
Tim Petersb9099c32002-11-12 22:08:10 +0000981 Returns a k length list of unique elements chosen from the population.
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000982
Tim Peters012c0a32002-08-16 03:40:07 +0000983- random.randrange(-sys.maxint-1, sys.maxint) no longer raises
984 OverflowError. That is, it now accepts any combination of 'start'
985 and 'stop' arguments so long as each is in the range of Python's
986 bounded integers.
987
Raymond Hettinger40f62172002-12-29 23:03:38 +0000988- Thanks to Raymond Hettinger, random.random() now uses a new core
989 generator. The Mersenne Twister algorithm is implemented in C,
990 threadsafe, faster than the previous generator, has an astronomically
991 large period (2**19937-1), creates random floats to full 53-bit
992 precision, and may be the most widely tested random number generator
993 in existence.
994
995 The random.jumpahead(n) method has different semantics for the new
996 generator. Instead of jumping n steps ahead, it uses n and the
997 existing state to create a new state. This means that jumpahead()
998 continues to support multi-threaded code needing generators of
999 non-overlapping sequences. However, it will break code which relies
1000 on jumpahead moving a specific number of steps forward.
1001
1002 The attributes random.whseed and random.__whseed have no meaning for
1003 the new generator. Code using these attributes should switch to a
1004 new class, random.WichmannHill which is provided for backward
1005 compatibility and to make an alternate generator available.
1006
Guido van Rossum4a57c332002-08-02 18:05:20 +00001007- New "algorithms" module: heapq, implements a heap queue. Thanks to
1008 Kevin O'Connor for the code and François Pinard for an entertaining
1009 write-up explaining the theory and practical uses of heaps.
1010
Marc-André Lemburg58e2ff22002-07-12 14:40:04 +00001011- New encoding for the Palm OS character set: palmos.
1012
Tim Peters943382c2002-07-07 03:59:34 +00001013- binascii.crc32() and the zipfile module had problems on some 64-bit
1014 platforms. These have been fixed. On a platform with 8-byte C longs,
1015 crc32() now returns a signed-extended 4-byte result, so that its value
1016 as a Python int is equal to the value computed a 32-bit platform.
1017
Martin v. Löwis7d650ca2002-06-30 15:05:00 +00001018- xml.dom.minidom.toxml and toprettyxml now take an optional encoding
1019 argument.
1020
Guido van Rossum9f7549b2002-06-10 21:39:42 +00001021- Some fixes in the copy module: when an object is copied through its
1022 __reduce__ method, there was no check for a __setstate__ method on
1023 the result [SF patch 565085]; deepcopy should treat instances of
1024 custom metaclasses the same way it treats instances of type 'type'
1025 [SF patch 560794].
1026
Guido van Rossum5033c8e2002-06-07 12:40:52 +00001027- Sockets now support timeout mode. After s.settimeout(T), where T is
1028 a float expressing seconds, subsequent operations raise an exception
1029 if they cannot be completed within T seconds. To disable timeout
Guido van Rossum79f0a102002-07-23 03:32:08 +00001030 mode, use s.settimeout(None). There's also a module function,
1031 socket.setdefaulttimeout(T), which sets the default for all sockets
1032 created henceforth.
Guido van Rossum5033c8e2002-06-07 12:40:52 +00001033
1034- getopt.gnu_getopt was added. This supports GNU-style option
1035 processing, where options can be mixed with non-option arguments.
Martin v. Löwis446a25f2002-06-06 10:58:36 +00001036
Michael W. Hudsonb0dc1a32002-06-04 18:27:35 +00001037- Stop using strings for exceptions. String objects used for
1038 exceptions are now classes deriving from Exception. The objects
1039 changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
1040 tabnanny.NannyNag, and xdrlib.Error.
Neal Norwitzb5b5a262002-06-04 17:14:07 +00001041
Walter Dörwald474458d2002-06-04 15:16:29 +00001042- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
1043 BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
1044 Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
1045 big endian systems were added to the codecs module. The old names
1046 BOM32_* and BOM64_* were off by a factor of 2.
1047
Guido van Rossumf9257822002-06-18 20:43:18 +00001048- Added conversion functions math.degrees() and math.radians().
Raymond Hettinger87f59ee2002-05-13 04:17:32 +00001049
Raymond Hettinger866964c2002-12-14 19:51:34 +00001050- math.log() now takes an optional argument: math.log(x[, base]).
1051
Raymond Hettinger9b1df1d2002-05-12 06:07:21 +00001052- ftplib.retrlines() now tests for callback is None rather than testing
1053 for False. Was causing an error when given a callback object which
1054 was callable but also returned len() as zero. The change may
1055 create new breakage if the caller relied on the undocumented behavior
1056 and called with callback set to [] or some other False value not
1057 identical to None.
1058
Tim Peters46c04e12002-05-05 20:40:00 +00001059- random.gauss() uses a piece of hidden state used by nothing else,
1060 and the .seed() and .whseed() methods failed to reset it. In other
1061 words, setting the seed didn't completely determine the sequence of
1062 results produced by random.gauss(). It does now. Programs repeatedly
1063 mixing calls to a seed method with calls to gauss() may see different
1064 results now.
1065
Fred Drake7f781c92002-05-01 20:33:53 +00001066- The pickle.Pickler class grew a clear_memo() method to mimic that
1067 provided by cPickle.Pickler.
1068
Tim Peters81b92512002-04-29 01:37:32 +00001069- difflib's SequenceMatcher class now does a dynamic analysis of
1070 which elements are so frequent as to constitute noise. For
1071 comparing files as sequences of lines, this generally works better
1072 than the IS_LINE_JUNK function, and function ndiff's linejunk
1073 argument defaults to None now as a result. A happy benefit is
1074 that SequenceMatcher may run much faster now when applied
1075 to large files with many duplicate lines (for example, C program
1076 text with lots of repeated "}" and "return NULL;" lines).
1077
Guido van Rossum256705b2002-04-23 13:29:43 +00001078- New Text.dump() method in Tkinter module.
1079
Marc-André Lemburg1ec71ea2002-04-17 20:33:40 +00001080- New distutils commands for building packagers were added to
1081 support pkgtool on Solaris and swinstall on HP-UX.
1082
1083- distutils now has a new abstract binary packager base class
1084 command/bdist_packager, which simplifies writing packagers.
1085 This will hopefully provide the missing bits to encourage
1086 people to submit more packagers, e.g. for Debian, FreeBSD
1087 and other systems.
1088
Guido van Rossumf9257822002-06-18 20:43:18 +00001089- The UTF-16, -LE and -BE stream readers now raise a
1090 NotImplementedError for all calls to .readline(). Previously, they
1091 used to just produce garbage or fail with an encoding error --
1092 UTF-16 is a 2-byte encoding and the C lib's line reading APIs don't
Marc-André Lemburg4179a012002-04-05 12:15:05 +00001093 work well with these.
1094
Martin v. Löwis5c137c22002-03-18 12:44:08 +00001095- compileall now supports quiet operation.
1096
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001097- The BaseHTTPServer now implements optional HTTP/1.1 persistent
Martin v. Löwis587c98c2002-03-17 18:37:22 +00001098 connections.
1099
Marc-André Lemburga5d2b4c2002-02-16 18:23:30 +00001100- socket module: the SSL support was broken out of the main
1101 _socket module C helper and placed into a new _ssl helper
1102 which now gets imported by socket.py if available and working.
1103
Marc-André Lemburg37aa5802002-02-10 21:42:47 +00001104- encodings package: added aliases for all supported IANA character
1105 sets
1106
Guido van Rossum606fe4e2001-12-28 20:57:14 +00001107- ftplib: to safeguard the user's privacy, anonymous login will use
1108 "anonymous@" as default password, rather than the real user and host
1109 name.
1110
Fred Drake36736122002-01-10 13:50:31 +00001111- webbrowser: tightened up the command passed to os.system() so that
1112 arbitrary shell code can't be executed because a bogus URL was
1113 passed in.
1114
Tim Peters11bd9942002-02-01 00:52:29 +00001115- gettext.translation has an optional fallback argument, and
Martin v. Löwisa55ffae2002-01-11 06:58:49 +00001116 gettext.find an optional all argument. Translations will now fallback
Martin v. Löwisd8996052002-11-21 21:45:32 +00001117 on a per-message basis. The module supports plural forms, by means
1118 of gettext.[d]ngettext and Translation.[u]ngettext.
Martin v. Löwis1be64192002-01-11 06:33:28 +00001119
Martin v. Löwis9668b932002-01-12 11:27:42 +00001120- distutils bdist commands now offer a --skip-build option.
1121
Walter Dörwaldb25c2b02002-03-21 10:38:40 +00001122- warnings.warn now accepts a Warning instance as first argument.
1123
Fred Drakefed7e852002-04-04 19:36:15 +00001124- The xml.sax.expatreader.ExpatParser class will no longer create
1125 circular references by using itself as the locator that gets passed
1126 to the content handler implementation. [SF bug #535474]
1127
Barry Warsaw47f3e2c2002-05-20 00:14:24 +00001128- The email.Parser.Parser class now properly parses strings regardless
1129 of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
1130 or CRLF). Also, the Header class's constructor default arguments
1131 has changed slightly so that an explicit maxlinelen value is always
Barry Warsaw497e5c42002-12-30 19:27:08 +00001132 honored, and so unicode conversion error handling can be specified.
Barry Warsaw47f3e2c2002-05-20 00:14:24 +00001133
David Goodgerf349e262003-01-03 03:30:21 +00001134- distutils' build_ext command now links C++ extensions with the C++
Gustavo Niemeyerf8ca8362002-11-05 16:50:05 +00001135 compiler available in the Makefile or CXX environment variable, if
David Goodgerf349e262003-01-03 03:30:21 +00001136 running under \*nix.
Gustavo Niemeyerf8ca8362002-11-05 16:50:05 +00001137
1138- New module bz2: provides a comprehensive interface for the bz2 compression
1139 library. It implements a complete file interface, one-shot (de)compression
1140 functions, and types for sequential (de)compression.
1141
David Goodgerf349e262003-01-03 03:30:21 +00001142- New pdb command 'pp' which is like 'p' except that it pretty-prints
Barry Warsaw5d8d6182002-11-05 22:41:33 +00001143 the value of its expression argument.
1144
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +00001145- Now bdist_rpm distutils command understands a verify_script option in
1146 the config file, including the contents of the referred filename in
1147 the "%verifyscript" section of the rpm spec file.
1148
Gustavo Niemeyer1456fde2002-11-25 17:25:04 +00001149- Fixed bug #495695: webbrowser module would run graphic browsers in a
1150 unix environment even if DISPLAY was not set. Also, support for
1151 skipstone browser was included.
1152
Gustavo Niemeyerd5ae01a2002-12-16 13:11:57 +00001153- Fixed bug #636769: rexec would run unallowed code if subclasses of
1154 strings were used as parameters for certain functions.
1155
Tim Petersaf8446f2001-12-21 21:36:50 +00001156Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001157-----------
Tim Petersaf8446f2001-12-21 21:36:50 +00001158
Martin v. Löwis0d1fdea2002-11-22 08:36:54 +00001159- pygettext.py now supports globbing on Windows, and accepts module
1160 names in addition to accepting file names.
1161
Guido van Rossum923e4ef2002-09-17 20:58:59 +00001162- The SGI demos (Demo/sgi) have been removed. Nobody thought they
1163 were interesting any more. (The SGI library modules and extensions
1164 are still there; it is believed that at least some of these are
1165 still used and useful.)
1166
Fred Drake40813b12002-08-05 15:24:19 +00001167- IDLE supports the new encoding declarations (PEP 263); it can also
1168 deal with legacy 8-bit files if they use the locale's encoding. It
1169 allows non-ASCII strings in the interactive shell and executes them
1170 in the locale's encoding.
Martin v. Löwis98ce7b72002-08-05 15:11:26 +00001171
Marc-André Lemburg46260092002-04-04 16:17:11 +00001172- freeze.py now produces binaries which can import shared modules,
1173 unlike before when this failed due to missing symbol exports in
1174 the generated binary.
1175
Tim Petersaf8446f2001-12-21 21:36:50 +00001176Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001177-----
Tim Petersaf8446f2001-12-21 21:36:50 +00001178
Martin v. Löwisdc461752002-11-06 21:59:33 +00001179- On Unix, IDLE is now installed automatically.
1180
Guido van Rossum6b3db552002-09-25 15:02:44 +00001181- The fpectl module is not built by default; it's dangerous or useless
1182 except in the hands of experts.
1183
Tim Petersf47630f2002-08-01 02:34:51 +00001184- The public Python C API will generally be declared using PyAPI_FUNC
Guido van Rossum6b3db552002-09-25 15:02:44 +00001185 and PyAPI_DATA macros, while Python extension module init functions
1186 will be declared with PyMODINIT_FUNC. DL_EXPORT/DL_IMPORT macros
1187 are deprecated.
Neal Norwitz1389f3e2002-07-22 13:21:10 +00001188
Tim Petersc6a3ff62002-07-08 22:11:52 +00001189- A bug was fixed that could cause COUNT_ALLOCS builds to segfault, or
1190 get into infinite loops, when a new-style class got garbage-collected.
1191 Unfortunately, to avoid this, the way COUNT_ALLOCS works requires
1192 that new-style classes be immortal in COUNT_ALLOCS builds. Note that
1193 COUNT_ALLOCS is not enabled by default, in either release or debug
1194 builds, and that new-style classes are immortal only in COUNT_ALLOCS
1195 builds.
1196
Tim Peters943382c2002-07-07 03:59:34 +00001197- Compiling out the cyclic garbage collector is no longer an option.
1198 The old symbol WITH_CYCLE_GC is now ignored, and Python.h arranges
1199 that it's always defined (for the benefit of any extension modules
1200 that may be conditionalizing on it). A bonus is that any extension
1201 type participating in cyclic gc can choose to participate in the
1202 Py_TRASHCAN mechanism now too; in the absence of cyclic gc, this used
1203 to require editing the core to teach the trashcan mechanism about the
1204 new type.
1205
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +00001206- According to Annex F of the current C standard,
Tim Peters1de41bf2002-07-03 03:31:20 +00001207
1208 The Standard C macro HUGE_VAL and its float and long double analogs,
1209 HUGE_VALF and HUGE_VALL, expand to expressions whose values are
1210 positive infinities.
1211
1212 Python only uses the double HUGE_VAL, and only to #define its own symbol
1213 Py_HUGE_VAL. Some platforms have incorrect definitions for HUGE_VAL.
1214 pyport.h used to try to worm around that, but the workarounds triggered
1215 other bugs on other platforms, so we gave up. If your platform defines
1216 HUGE_VAL incorrectly, you'll need to #define Py_HUGE_VAL to something
1217 that works on your platform. The only instance of this I'm sure about
1218 is on an unknown subset of Cray systems, described here:
1219
1220 http://www.cray.com/swpubs/manuals/SN-2194_2.0/html-SN-2194_2.0/x3138.htm
1221
1222 Presumably 2.3a1 breaks such systems. If anyone uses such a system, help!
1223
Martin v. Löwisa3fb4f72002-06-09 13:33:54 +00001224- The configure option --without-doc-strings can be used to remove the
1225 doc strings from the builtin functions and modules; this reduces the
1226 size of the executable.
1227
Guido van Rossumadd88062002-08-15 14:01:14 +00001228- The universal newlines option (PEP 278) is on by default. On Unix
1229 it can be disabled by passing --without-universal-newlines to the
1230 configure script. On other platforms, remove
1231 WITH_UNIVERSAL_NEWLINES from pyconfig.h.
Tim Peters639295f2002-04-21 07:30:30 +00001232
Martin v. Löwis1142de32002-03-29 16:28:31 +00001233- On Unix, a shared libpython2.3.so can be created with --enable-shared.
1234
Tim Peters8deda702002-03-30 10:06:07 +00001235- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
1236 preprocessor symbols were eliminated. The internal decisions they
1237 controlled stopped being experimental long ago.
Tim Peters1f7df352002-03-29 03:29:08 +00001238
Fred Drake7d28b732002-05-02 21:17:00 +00001239- The tools used to build the documentation now work under Cygwin as
1240 well as Unix.
1241
Skip Montanaro57454e52002-06-14 20:30:31 +00001242- The bsddb and dbm module builds have been changed to try and avoid version
1243 skew problems and disable linkage with Berkeley DB 1.85 unless the
1244 installer knows what s/he's doing. See the section on building these
1245 modules in the README file for details.
1246
Tim Petersaf8446f2001-12-21 21:36:50 +00001247C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001248-----
Tim Petersaf8446f2001-12-21 21:36:50 +00001249
Neil Schemenauer6c194762002-11-18 16:19:39 +00001250- PyNumber_Check() now returns true for string and unicode objects.
1251 This is a result of these types having a partially defined
Guido van Rossum1d267402002-11-18 16:27:16 +00001252 tp_as_number slot. (This is not a feature, but an indication that
Walter Dörwalda1a61f92002-11-19 21:20:25 +00001253 PyNumber_Check() is not very useful to determine numeric behavior.
Guido van Rossum1d267402002-11-18 16:27:16 +00001254 It may be deprecated.)
Neil Schemenauer6c194762002-11-18 16:19:39 +00001255
Guido van Rossum45ec02a2002-08-19 21:43:18 +00001256- The string object's layout has changed: the pointer member
1257 ob_sinterned has been replaced by an int member ob_sstate. On some
1258 platforms (e.g. most 64-bit systems) this may change the offset of
1259 the ob_sval member, so as a precaution the API_VERSION has been
1260 incremented. The apparently unused feature of "indirect interned
1261 strings", supported by the ob_sinterned member, is gone. Interned
1262 strings are now usually mortal; theres a new API,
1263 PyString_InternImmortal() that creates immortal interned strings.
1264 (The ob_sstate member can only take three values; however, while
1265 making it a char saves a few bytes per string object on average, in
1266 it also slowed things down a bit because ob_sval was no longer
1267 aligned.)
1268
Guido van Rossumfdb86482002-08-14 21:20:32 +00001269- The Py_InitModule*() functions now accept NULL for the 'methods'
1270 argument. Modules without global functions are becoming more common
1271 now that factories can be types rather than functions.
1272
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +00001273- New C API PyUnicode_FromOrdinal() which exposes unichr() at C
1274 level.
1275
Thomas Heller085358a2002-07-29 14:27:41 +00001276- New functions PyErr_SetExcFromWindowsErr() and
1277 PyErr_SetExcFromWindowsErrWithFilename(). Similar to
1278 PyErr_SetFromWindowsErrWithFilename() and
1279 PyErr_SetFromWindowsErr(), but they allow to specify
1280 the exception type to raise. Available on Windows.
1281
Tim Peters7c321a82002-07-09 02:57:01 +00001282- Py_FatalError() is now declared as taking a const char* argument. It
1283 was previously declared without const. This should not affect working
1284 code.
1285
Martin v. Löwis01f94bd2002-05-08 08:44:21 +00001286- Added new macro PySequence_ITEM(o, i) that directly calls
1287 sq_item without rechecking that o is a sequence and without
1288 adjusting for negative indices.
1289
Fred Draked0ba6362002-05-02 21:28:26 +00001290- PyRange_New() now raises ValueError if the fourth argument is not 1.
1291 This is part of the removal of deprecated features of the xrange
1292 object.
1293
Guido van Rossum517c7d42002-04-26 02:49:14 +00001294- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
1295 coercion if both arguments have the same type but this type has the
1296 CHECKTYPES flag set. This is to better support proxies.
1297
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00001298- The type of tp_free has been changed from "``void (*)(PyObject *)``" to
1299 "``void (*)(void *)``".
Neil Schemenauer9344b142002-04-12 23:00:08 +00001300
1301- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
1302
Guido van Rossum0986d822002-04-08 01:38:42 +00001303- A type can now inherit its metatype from its base type. Previously,
1304 when PyType_Ready() was called, if ob_type was found to be NULL, it
1305 was always set to &PyType_Type; now it is set to base->ob_type,
1306 where base is tp_base, defaulting to &PyObject_Type.
1307
1308- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
1309
Neil Schemenauerc9abc1d2002-05-08 14:14:41 +00001310- The PyCore_* family of APIs have been removed.
Neil Schemenauer9d50d132002-03-22 17:06:59 +00001311
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001312- The "u#" parser marker will now pass through Unicode objects as-is
Marc-André Lemburg3e3eacb2002-01-09 16:21:27 +00001313 without going through the buffer API.
1314
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001315- The enumerators of cmp_op have been renamed to use the prefix ``PyCmp_``.
Martin v. Löwis7198a522002-01-01 19:59:11 +00001316
Tim Peters10a3bb52001-12-25 19:07:38 +00001317- An old #define of ANY as void has been removed from pyport.h. This
1318 hasn't been used since Python's pre-ANSI days, and the #define has
1319 been marked as obsolete since then. SF bug 495548 says it created
1320 conflicts with other packages, so keeping it around wasn't harmless.
1321
Tim Petersaf8446f2001-12-21 21:36:50 +00001322- Because Python's magic number scheme broke on January 1st, we decided
1323 to stop Python development. Thanks for all the fish!
1324
Tim Petersfb05db22002-03-11 00:24:00 +00001325- Some of us don't like fish, so we changed Python's magic number
Marc-André Lemburge92e0a92002-02-09 11:28:43 +00001326 scheme to a new one. See Python/import.c for details.
1327
Tim Petersaf8446f2001-12-21 21:36:50 +00001328New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001329-------------
Tim Petersaf8446f2001-12-21 21:36:50 +00001330
Martin v. Löwis79acb9e2002-12-06 12:48:53 +00001331- OpenVMS is now supported.
1332
Martin v. Löwisf90ae202002-06-11 06:22:31 +00001333- AtheOS is now supported.
1334
Andrew MacIntyre161ad0e2002-08-04 07:25:58 +00001335- the EMX runtime environment on OS/2 is now supported.
1336
Martin v. Löwisa6e97582002-01-01 18:41:33 +00001337- GNU/Hurd is now supported.
1338
Tim Petersaf8446f2001-12-21 21:36:50 +00001339Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001340-----
1341
Fred Drake4dd0f7e2002-11-26 21:44:56 +00001342- The regrtest.py script's -u option now provides a way to say "allow
1343 all resources except this one." For example, to allow everything
1344 except bsddb, give the option '-uall,-bsddb'.
Tim Petersaf8446f2001-12-21 21:36:50 +00001345
1346Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001347-------
Tim Petersaf8446f2001-12-21 21:36:50 +00001348
Tim Peters19cf4ee2002-11-23 03:49:08 +00001349- The Windows distribution now ships with version 4.0.14 of the
1350 Sleepycat Berkeley database library. This should be a huge
1351 improvement over the previous Berkeley DB 1.85, which had many
1352 bugs.
1353 XXX What are the licensing issues here?
Tim Peters84c7a3f2002-11-23 18:48:06 +00001354 XXX If a user has a database created with a previous verion of
1355 XXX Python, what must they do to convert it?
1356 XXX I'm still not sure how to link this thing (see PCbuild/readme.txt).
Tim Peters19cf4ee2002-11-23 03:49:08 +00001357 XXX The version # is likely to change before 2.3a1.
Tim Peterse820cb62002-12-16 20:57:22 +00001358
1359- The Windows distribution now ships with a Secure Sockets Library (SLL)
Mark Hammondc3de0082002-12-03 06:16:08 +00001360 module (_ssl.pyd)
Tim Peters19cf4ee2002-11-23 03:49:08 +00001361
Tim Peters857fb4c2002-11-14 23:31:58 +00001362- The Windows distribution now ships with Tcl/Tk version 8.4.1 (it
1363 previously shipped with Tcl/Tk 8.3.2).
1364
Tim Peters37dfb012002-11-11 19:51:33 +00001365- When Python is built under a Microsoft compiler, sys.version now
1366 includes the compiler version number (_MSC_VER). For example, under
1367 MSVC 6, sys.version constains the substring "MSC v.1200 ". 1200 is
1368 the value of _MSC_VER under MSVC 6.
1369
Tim Peters08e72952002-04-16 20:48:01 +00001370- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
1371 of that has been fixed in the installer (disabled Wise's "delete in-
1372 use files" uninstall option).
1373
Guido van Rossum181e41a2002-04-06 00:23:25 +00001374- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
1375
Tim Peters33187922002-04-04 20:02:04 +00001376- The installer now installs Start menu shortcuts under (the local
1377 equivalent of) "All Users" when doing an Admin install.
1378
Tim Petersfb05db22002-03-11 00:24:00 +00001379- file.truncate([newsize]) now works on Windows for all newsize values.
1380 It used to fail if newsize didn't fit in 32 bits, reflecting a
1381 limitation of MS _chsize (which is no longer used).
1382
Tim Petersab034fa2002-02-01 11:27:43 +00001383- os.waitpid() is now implemented for Windows, and can be used to block
1384 until a specified process exits. This is similar to, but not exactly
1385 the same as, os.waitpid() on POSIX systems. If you're waiting for
1386 a specific process whose pid was obtained from one of the spawn()
1387 functions, the same Python os.waitpid() code works across platforms.
Tim Peters33187922002-04-04 20:02:04 +00001388 See the docs for details. The docs were changed to clarify that
1389 spawn functions return, and waitpid requires, a process handle on
1390 Windows (not the same thing as a Windows process id).
Tim Petersab034fa2002-02-01 11:27:43 +00001391
Tim Peters11bd9942002-02-01 00:52:29 +00001392- New tempfile.TemporaryFile implementation for Windows: this doesn't
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001393 need a TemporaryFileWrapper wrapper anymore, and should be immune
Tim Peters11bd9942002-02-01 00:52:29 +00001394 to a nasty problem: before 2.3, if you got a temp file on Windows, it
1395 got wrapped in an object whose close() method first closed the
1396 underlying file, then deleted the file. This usually worked fine.
1397 However, the spawn family of functions on Windows create (at a low C
1398 level) the same set of open files in the spawned process Q as were
1399 open in the spawning process P. If a temp file f was among them, then
1400 doing f.close() in P first closed P's C-level file handle on f, but Q's
1401 C-level file handle on f remained open, so the attempt in P to delete f
1402 blew up with a "Permission denied" error (Windows doesn't allow
1403 deleting open files). This was surprising, subtle, and difficult to
1404 work around.
1405
1406- The os module now exports all the symbolic constants usable with the
1407 low-level os.open() on Windows: the new constants in 2.3 are
1408 O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
1409 The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
1410 O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
1411 to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
1412 (so specify both if you want both; note that neither is useful unless
1413 specified with O_CREAT too).
1414
Tim Petersaf8446f2001-12-21 21:36:50 +00001415Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001416----
1417
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001418- Mac/Relnotes is gone, the release notes are now here.
Tim Petersaf8446f2001-12-21 21:36:50 +00001419
Just van Rossume1ebd802003-02-10 10:06:18 +00001420- Python (the OSX-only, unix-based version, not the OS9-compatible CFM
1421 version) now fully supports unicode strings as arguments to various file
1422 system calls, eg. open(), file(), os.stat() and os.listdir().
1423
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001424- The current naming convention for Python on the Macintosh is that MacPython
1425 refers to the unix-based OSX-only version, and MacPython-OS9 refers to the
1426 CFM-based version that runs on both OS9 and OSX.
1427
1428- All MacPython-OS9 functionality is now available in an OSX unix build,
1429 including the Carbon modules, the IDE, OSA support, etc. A lot of this
1430 will only work correctly in a framework build, though, because you cannot
1431 talk to the window manager unless your application is run from a .app
1432 bundle. There is a command line tool "pythonw" that runs your script
1433 with an interpreter living in such a .app bundle, this interpreter should
1434 be used to run any Python script using the window manager (including
1435 Tkinter or wxPython scripts).
Tim Petersbbc5d162003-01-02 16:02:27 +00001436
Jack Jansen8bb80db2002-12-30 22:42:43 +00001437- Most of Mac/Lib has moved to Lib/plat-mac, which is again used both in
1438 MacPython-OSX and MacPython-OS9. The only modules remaining in Mac/Lib
1439 are specifically for MacPython-OS9 (CFM support, preference resources, etc).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001440
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001441- A new utility PythonLauncher will start a Python interpreter when a .py or
1442 .pyw script is double-clicked in the Finder. By default .py scripts are
1443 run with a normal Python interpreter in a Terminal window and .pyw
1444 files are run with a window-aware pythonw interpreter without a Terminal
1445 window, but all this can be customized.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001446
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001447- MacPython-OS9 is now Carbon-only, so it runs on Mac OS 9 or Mac OS X and
1448 possibly on Mac OS 8.6 with the right CarbonLib installed, but not on earlier
1449 releases.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001450
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001451- Many tools such as BuildApplet.py and gensuitemodule.py now support a command
1452 line interface too.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001453
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001454- All the Carbon classes are now PEP253 compliant, meaning that you can
1455 subclass them from Python. Most of the attributes have gone, you should
1456 now use the accessor function call API, which is also what Apple's
1457 documentation uses. Some attributes such as grafport.visRgn are still
1458 available for convenience.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001459
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001460- New Carbon modules File (implementing the APIs in Files.h and Aliases.h)
1461 and Folder (APIs from Folders.h). The old macfs builtin module is
1462 gone, and replaced by a Python wrapper around the new modules.
1463
1464- Pathname handling should now be fully consistent: MacPython-OSX always uses
1465 unix pathnames and MacPython-OS9 always uses colon-separated Mac pathnames
1466 (also when running on Mac OS X).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001467
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001468- New Carbon modules Help and AH give access to the Carbon Help Manager.
1469 There are hooks in the IDE to allow accessing the Python documentation
1470 (and Apple's Carbon and Cocoa documentation) through the Help Viewer.
1471 See Mac/OSX/README for converting the Python documentation to a
1472 Help Viewer comaptible form and installing it.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001473
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001474- OSA support has been redesigned and the generated Python classes now
1475 mirror the inheritance defined by the underlying OSA classes.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001476
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001477- MacPython no longer maps both \r and \n to \n on input for any text file.
1478 This feature has been replaced by universal newline support (PEP278).
Tim Peters0bf60bd2003-01-08 20:40:01 +00001479
Jack Jansen05d284b2003-01-08 16:29:17 +00001480- The default encoding for Python sourcefiles in MacPython-OS9 is no longer
1481 mac-roman (or whatever your local Mac encoding was but "ascii", like on
1482 other platforms. If you really need sourcefiles with Mac characters in them
1483 you can change this in site.py.
Tim Petersaf8446f2001-12-21 21:36:50 +00001484
Tim Peters909c0912001-12-14 23:16:18 +00001485What's New in Python 2.2 final?
Tim Peters909c0912001-12-14 23:16:18 +00001486===============================
1487
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001488*Release date: 21-Dec-2001*
1489
Tim Peters909c0912001-12-14 23:16:18 +00001490Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001491--------------------------------------------
Tim Peters909c0912001-12-14 23:16:18 +00001492
Barry Warsaw52acb492001-12-21 20:04:22 +00001493- pickle.py, cPickle: allow pickling instances of new-style classes
1494 with a custom metaclass.
1495
Tim Peters909c0912001-12-14 23:16:18 +00001496Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001497-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001498
Barry Warsaw52acb492001-12-21 20:04:22 +00001499- weakref proxy object: when comparing, unwrap both arguments if both
1500 are proxies.
1501
Tim Peters909c0912001-12-14 23:16:18 +00001502Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001503-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001504
Barry Warsaw52acb492001-12-21 20:04:22 +00001505- binascii.b2a_base64(): fix a potential buffer overrun when encoding
1506 very short strings.
1507
1508- cPickle: the obscure "fast" mode was suspected of causing stack
1509 overflows on the Mac. Hopefully fixed this by setting the recursion
1510 limit much smaller. If the limit is too low (it only affects
1511 performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
1512 when compiling cPickle.c (or in pyconfig.h).
1513
Tim Peters909c0912001-12-14 23:16:18 +00001514Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001515-------
Tim Peters909c0912001-12-14 23:16:18 +00001516
Barry Warsaw52acb492001-12-21 20:04:22 +00001517- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
1518 close or delete time).
1519
1520- rfc822.py: fixed a bug where the address '<>' was converted to None
1521 instead of an empty string (also fixes the email.Utils module).
1522
1523- xmlrpclib.py: version 1.0.0; uses precision for doubles.
1524
1525- test suite: the pickle and cPickle tests were not executing any code
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001526 when run from the standard regression test.
Barry Warsaw52acb492001-12-21 20:04:22 +00001527
Tim Peters909c0912001-12-14 23:16:18 +00001528Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001529-----------
Tim Peters909c0912001-12-14 23:16:18 +00001530
1531Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001532-----
Tim Peters909c0912001-12-14 23:16:18 +00001533
1534C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001535-----
Tim Peters909c0912001-12-14 23:16:18 +00001536
1537New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001538-------------
Tim Peters909c0912001-12-14 23:16:18 +00001539
1540Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001541-----
Tim Peters909c0912001-12-14 23:16:18 +00001542
1543Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001544-------
Tim Peters909c0912001-12-14 23:16:18 +00001545
Barry Warsaw52acb492001-12-21 20:04:22 +00001546- distutils package: fixed broken Windows installers (bdist_wininst).
1547
1548- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
1549 instances are deleted at process exit time.
1550
1551- socket.py: prevent mysterious warnings when socket instances are
1552 deleted at process exit time.
1553
1554- posixmodule.c: fix a Windows crash with stat() of a filename ending
1555 in backslash.
1556
Tim Peters909c0912001-12-14 23:16:18 +00001557Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001558----
Tim Peters909c0912001-12-14 23:16:18 +00001559
Barry Warsaw52acb492001-12-21 20:04:22 +00001560- The Carbon toolbox modules have been upgraded to Universal Headers
1561 3.4, and experimental CoreGraphics and CarbonEvents modules have
1562 been added. All only for framework-enabled MacOSX.
1563
Tim Peters909c0912001-12-14 23:16:18 +00001564
Tim Peters6272dfd2001-12-13 19:34:00 +00001565What's New in Python 2.2c1?
Tim Petersb3c9af12001-11-17 00:21:57 +00001566===========================
1567
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001568*Release date: 14-Dec-2001*
1569
Tim Petersb3c9af12001-11-17 00:21:57 +00001570Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001571--------------------------------------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001572
Barry Warsaw06557452001-12-14 20:47:12 +00001573- Guido's tutorial introduction to the new type/class features has
1574 been extensively updated. See
1575
1576 http://www.python.org/2.2/descrintro.html
1577
1578 That remains the primary documentation in this area.
1579
Guido van Rossum33bab012001-12-05 22:45:48 +00001580- Fixed a leak: instance variables declared with __slots__ were never
1581 deleted!
1582
Guido van Rossum4b800852001-12-03 00:54:52 +00001583- The "delete attribute" method of descriptor objects is called
1584 __delete__, not __del__. In previous releases, it was mistakenly
1585 called __del__, which created an unfortunate overloading condition
1586 with finalizers. (The "get attribute" and "set attribute" methods
1587 are still called __get__ and __set__, respectively.)
1588
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001589- Some subtle issues with the super built-in were fixed:
1590
1591 (a) When super itself is subclassed, its __get__ method would still
1592 return an instance of the base class (i.e., of super).
1593
1594 (b) super(C, C()).__class__ would return C rather than super. This
1595 is confusing. To fix this, I decided to change the semantics of
1596 super so that it only applies to code attributes, not to data
1597 attributes. After all, overriding data attributes is not
1598 supported anyway.
1599
1600 (c) The __get__ method didn't check whether the argument was an
1601 instance of the type used in creation of the super instance.
1602
Guido van Rossumcd7b7d62001-12-04 21:02:07 +00001603- Previously, hash() of an instance of a subclass of a mutable type
1604 (list or dictionary) would return some value, rather than raising
1605 TypeError. This has been fixed. Also, directly calling
1606 dict.__hash__ and list.__hash__ now raises the same TypeError
1607 (previously, these were the same as object.__hash__).
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001608
Guido van Rossumd331cb52001-12-05 19:46:42 +00001609- New-style objects now support deleting their __dict__. This is for
1610 all intents and purposes equivalent to assigning a brand new empty
1611 dictionary, but saves space if the object is not used further.
1612
Tim Petersb3c9af12001-11-17 00:21:57 +00001613Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001614-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001615
Tim Peters3caca232001-12-06 06:23:26 +00001616- -Qnew now works as documented in PEP 238: when -Qnew is passed on
1617 the command line, all occurrences of "/" use true division instead
1618 of classic division. See the PEP for details. Note that "all"
1619 means all instances in library and 3rd-party modules, as well as in
1620 your own code. As the PEP says, -Qnew is intended for use only in
1621 educational environments with control over the libraries in use.
Tim Petersbf72fe22001-12-11 21:43:14 +00001622 Note that test_coercion.py in the standard Python test suite fails
1623 under -Qnew; this is expected, and won't be repaired until true
1624 division becomes the default (in the meantime, test_coercion is
1625 testing the current rules).
Tim Peters3caca232001-12-06 06:23:26 +00001626
Fred Drake6c01e252001-12-14 17:08:12 +00001627- complex() now only allows the first argument to be a string
1628 argument, and raises TypeError if either the second arg is a string
1629 or if the second arg is specified when the first is a string.
1630
Tim Petersb3c9af12001-11-17 00:21:57 +00001631Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001632-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001633
Martin v. Löwis560da622001-11-24 09:24:51 +00001634- gc.get_referents was renamed to gc.get_referrers.
1635
Tim Petersb3c9af12001-11-17 00:21:57 +00001636Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001637-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001638
Tim Peters25059d32001-12-07 20:35:43 +00001639- Functions in the os.spawn() family now release the global interpreter
1640 lock around calling the platform spawn. They should always have done
1641 this, but did not before 2.2c1. Multithreaded programs calling
1642 an os.spawn function with P_WAIT will no longer block all Python threads
1643 until the spawned program completes. It's possible that some programs
1644 relies on blocking, although more likely by accident than by design.
1645
Martin v. Löwis3a89b2b2001-11-25 14:35:58 +00001646- webbrowser defaults to netscape.exe on OS/2 now.
1647
Martin v. Löwis652e1912001-11-25 14:50:56 +00001648- Tix.ResizeHandle exposes detach_widget, hide, and show.
1649
Martin v. Löwis714d2e22001-12-02 12:26:03 +00001650- The charset alias windows_1252 has been added.
1651
Barry Warsaw06557452001-12-14 20:47:12 +00001652- types.StringTypes is a tuple containing the defined string types;
1653 usually this will be (str, unicode), but if Python was compiled
1654 without Unicode support it will be just (str,).
1655
1656- The pulldom and minidom modules were synchronized to PyXML.
1657
Tim Petersb3c9af12001-11-17 00:21:57 +00001658Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001659-----------
Tim Petersb3c9af12001-11-17 00:21:57 +00001660
Barry Warsaw06557452001-12-14 20:47:12 +00001661- A new script called Tools/scripts/google.py was added, which fires
1662 off a search on Google.
1663
Tim Petersb3c9af12001-11-17 00:21:57 +00001664Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001665-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001666
Barry Warsaw06557452001-12-14 20:47:12 +00001667- Note that release builds of Python should arrange to define the
1668 preprocessor symbol NDEBUG on the command line (or equivalent).
1669 In the 2.2 pre-release series we tried to define this by magic in
1670 Python.h instead, but it proved to cause problems for extension
1671 authors. The Unix, Windows and Mac builds now all define NDEBUG in
1672 release builds via cmdline (or equivalent) instead. Ports to
1673 other platforms should do likewise.
1674
Jack Jansen1999ef42001-12-06 21:47:20 +00001675- It is no longer necessary to use --with-suffix when building on a
1676 case-insensitive file system (such as Mac OS X HFS+). In the build
1677 directory an extension is used, but not in the installed python.
1678
Tim Petersb3c9af12001-11-17 00:21:57 +00001679C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001680-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001681
Tim Petersf582b822001-12-11 18:51:08 +00001682- New function PyDict_MergeFromSeq2() exposes the builtin dict
1683 constructor's logic for updating a dictionary from an iterable object
1684 producing key-value pairs.
1685
Tim Peterscffed4b2001-11-29 03:26:37 +00001686- PyArg_ParseTupleAndKeywords() requires that the number of entries in
Tim Petersf582b822001-12-11 18:51:08 +00001687 the keyword list equal the number of argument specifiers. This
Tim Peterscffed4b2001-11-29 03:26:37 +00001688 wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
1689 dump core in some bad cases. This has been repaired. As a result,
1690 PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
1691 previously went unchallenged.
1692
Tim Petersb3c9af12001-11-17 00:21:57 +00001693New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001694-------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001695
1696Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001697-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001698
1699Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001700-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001701
1702Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001703----
Tim Petersb3c9af12001-11-17 00:21:57 +00001704
Jack Jansenffa260f2001-12-06 21:14:00 +00001705- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
1706 without any trailing digits.
Tim Petersb3c9af12001-11-17 00:21:57 +00001707
Barry Warsaw06557452001-12-14 20:47:12 +00001708- Changed logic for finding python home in Mac OS X framework Pythons.
1709 Now sys.executable points to the executable again, in stead of to
1710 the shared library. The latter is used only for locating the python
1711 home.
1712
1713
Tim Peters84362bc2001-10-19 17:55:30 +00001714What's New in Python 2.2b2?
Tim Peters84362bc2001-10-19 17:55:30 +00001715===========================
1716
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001717*Release date: 16-Nov-2001*
1718
Tim Peters84362bc2001-10-19 17:55:30 +00001719Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001720--------------------------------------------
Tim Peters84362bc2001-10-19 17:55:30 +00001721
Guido van Rossum3d27df02001-11-15 20:27:54 +00001722- Multiple inheritance mixing new-style and classic classes in the
1723 list of base classes is now allowed, so this works now:
Tim Peters76f7fe32001-11-15 20:02:21 +00001724
1725 class Classic: pass
Guido van Rossum3d27df02001-11-15 20:27:54 +00001726 class Mixed(Classic, object): pass
Tim Peters76f7fe32001-11-15 20:02:21 +00001727
1728 The MRO (method resolution order) for each base class is respected
1729 according to its kind, but the MRO for the derived class is computed
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001730 using new-style MRO rules if any base class is a new-style class.
Tim Peters76f7fe32001-11-15 20:02:21 +00001731 This needs to be documented.
1732
Tim Petersa427a2b2001-10-29 22:25:45 +00001733- The new builtin dictionary() constructor, and dictionary type, have
1734 been renamed to dict. This reflects a decade of common usage.
1735
Guido van Rossum3fc08d22001-11-15 20:33:10 +00001736- dict() now accepts an iterable object producing 2-sequences. For
1737 example, dict(d.items()) == d for any dictionary d. The argument,
1738 and the elements of the argument, can be any iterable objects.
1739
Guido van Rossum7ad2d1e2001-10-29 22:11:00 +00001740- New-style classes can now have a __del__ method, which is called
1741 when the instance is deleted (just like for classic classes).
1742
Guido van Rossum12d955c2001-10-26 14:56:06 +00001743- Assignment to object.__dict__ is now possible, for objects that are
1744 instances of new-style classes that have a __dict__ (unless the base
1745 class forbids it).
1746
Guido van Rossumc8e56452001-10-22 00:43:43 +00001747- Methods of built-in types now properly check for keyword arguments
1748 (formerly these were silently ignored). The only built-in methods
1749 that take keyword arguments are __call__, __init__ and __new__.
1750
Guido van Rossum86443212001-10-27 22:28:54 +00001751- The socket function has been converted to a type; see below.
1752
Tim Peters84362bc2001-10-19 17:55:30 +00001753Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001754-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001755
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001756- Assignment to __debug__ raises SyntaxError at compile-time. This
1757 was promised when 2.1c1 was released as "What's New in Python 2.1c1"
Barry Warsaw012852b2001-11-16 16:17:27 +00001758 (see below) says.
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001759
Guido van Rossum12d955c2001-10-26 14:56:06 +00001760- Clarified the error messages for unsupported operands to an operator
1761 (like 1 + '').
1762
Tim Peters84362bc2001-10-19 17:55:30 +00001763Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001764-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001765
Tim Peters5ebfd362001-11-13 23:11:19 +00001766- mmap has a new keyword argument, "access", allowing a uniform way for
1767 both Windows and Unix users to create read-only, write-through and
1768 copy-on-write memory mappings. This was previously possible only on
1769 Unix. A new keyword argument was required to support this in a
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001770 uniform way because the mmap() signatures had diverged across
Tim Peters5ebfd362001-11-13 23:11:19 +00001771 platforms. Thanks to Jay T Miller for repairing this!
1772
Tim Peters169ded02001-11-03 19:57:21 +00001773- By default, the gc.garbage list now contains only those instances in
1774 unreachable cycles that have __del__ methods; in 2.1 it contained all
1775 instances in unreachable cycles. "Instances" here has been generalized
1776 to include instances of both new-style and old-style classes.
1777
Guido van Rossum12d955c2001-10-26 14:56:06 +00001778- The socket module defines a new method for socket objects,
1779 sendall(). This is like send() but may make multiple calls to
Guido van Rossum86443212001-10-27 22:28:54 +00001780 send() until all data has been sent. Also, the socket function has
1781 been converted to a subclassable type, like list and tuple (etc.)
1782 before it; socket and SocketType are now the same thing.
Guido van Rossum12d955c2001-10-26 14:56:06 +00001783
1784- Various bugfixes to the curses module. There is now a test suite
1785 for the curses module (you have to run it manually).
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001786
Guido van Rossum692adf12001-10-30 03:03:03 +00001787- binascii.b2a_base64 no longer places an arbitrary restriction of 57
1788 bytes on its input.
1789
Tim Peters84362bc2001-10-19 17:55:30 +00001790Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001791-------
Tim Peters84362bc2001-10-19 17:55:30 +00001792
Tim Peters5ebfd362001-11-13 23:11:19 +00001793- tkFileDialog exposes a Directory class and askdirectory
Martin v. Löwis25ee87c2001-11-07 22:38:08 +00001794 convenience function.
1795
Tim Peters75335872001-11-03 19:35:43 +00001796- Symbolic group names in regular expressions must be unique. For
1797 example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
1798 single name can't mean both "group 1" and "group 2" simultaneously.
Barry Warsaw012852b2001-11-16 16:17:27 +00001799 Python 2.2 detects this error at regexp compilation time;
1800 previously, the error went undetected, and results were
1801 unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
1802 pattern.subn() methods have been rewritten in C. Also, an
1803 experimental function/method finditer() has been added, which works
1804 like findall() but returns an iterator.
Tim Peters75335872001-11-03 19:35:43 +00001805
Martin v. Löwisb7b32602001-11-02 23:48:20 +00001806- Tix exposes more commands through the classes DirSelectBox,
1807 DirSelectDialog, ListNoteBook, Meter, CheckList, and the
1808 methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
1809 tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
1810
Tim Peters98791af2001-10-23 01:59:54 +00001811- Traceback objects are now scanned by cyclic garbage collection, so
1812 cycles created by casual use of sys.exc_info() no longer cause
1813 permanent memory leaks (provided garbage collection is enabled).
1814
Guido van Rossum49192142001-10-24 20:51:44 +00001815- os.extsep -- a new variable needed by the RISCOS support. It is the
1816 separator used by extensions, and is '.' on all platforms except
1817 RISCOS, where it is '/'. There is no need to use this variable
1818 unless you have a masochistic desire to port your code to RISCOS.
1819
Barry Warsaw012852b2001-11-16 16:17:27 +00001820- mimetypes.py has optional support for non-standard, but commonly
1821 found types. guess_type() and guess_extension() now accept an
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001822 optional 'strict' flag, defaulting to true, which controls whether
Barry Warsaw012852b2001-11-16 16:17:27 +00001823 recognize non-standard types or not. A few non-standard types we
1824 know about have been added. Also, when run as a script, there are
1825 new -l and -e options.
1826
1827- statcache is now deprecated.
1828
1829- email.Utils.formatdate() now produces the preferred RFC 2822 style
1830 dates with numeric timezones (it used to produce obsolete dates
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001831 hard coded to "GMT" timezone). An optional 'localtime' flag is
Barry Warsaw012852b2001-11-16 16:17:27 +00001832 added to produce dates in the local timezone, with daylight savings
1833 time properly taken into account.
1834
1835- In pickle and cPickle, instead of masking errors in load() by
1836 transforming them into SystemError, we let the original exception
1837 propagate out. Also, implement support for __safe_for_unpickling__
1838 in pickle, as it already was supported in cPickle.
1839
Tim Peters84362bc2001-10-19 17:55:30 +00001840Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001841-----------
Tim Peters84362bc2001-10-19 17:55:30 +00001842
1843Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001844-----
Tim Peters84362bc2001-10-19 17:55:30 +00001845
Barry Warsaw012852b2001-11-16 16:17:27 +00001846- The dbm module is built using libdb1 if available. The bsddb module
1847 is built with libdb3 if available.
1848
1849- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
1850
Tim Peters84362bc2001-10-19 17:55:30 +00001851C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001852-----
Tim Peters84362bc2001-10-19 17:55:30 +00001853
Tim Peters1fc240e2001-10-26 05:06:50 +00001854- New function PySequence_Fast_GET_SIZE() returns the size of a non-
1855 NULL result from PySequence_Fast(), more quickly than calling
1856 PySequence_Size().
1857
Barry Warsaw012852b2001-11-16 16:17:27 +00001858- New argument unpacking function PyArg_UnpackTuple() added.
1859
1860- New functions PyObject_CallFunctionObjArgs() and
1861 PyObject_CallMethodObjArgs() have been added to make it more
1862 convenient and efficient to call functions and methods from C.
1863
1864- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
1865 possible that this will propagate errors it didn't before.
1866
1867- New function PyObject_CheckReadBuffer(), which returns true if its
1868 argument supports the single-segment readable buffer interface.
1869
Tim Peters84362bc2001-10-19 17:55:30 +00001870New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001871-------------
Tim Peters84362bc2001-10-19 17:55:30 +00001872
Guido van Rossum86443212001-10-27 22:28:54 +00001873- We've finally confirmed that this release builds on HP-UX 11.00,
1874 *with* threads, and passes the test suite.
1875
Tim Peters7a33d8b2001-11-05 02:51:07 +00001876- Thanks to a series of patches from Michael Muller, Python may build
1877 again under OS/2 Visual Age C++.
1878
Guido van Rossum49192142001-10-24 20:51:44 +00001879- Updated RISCOS port by Dietmar Schwertberger.
1880
Tim Peters84362bc2001-10-19 17:55:30 +00001881Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001882-----
Tim Peters84362bc2001-10-19 17:55:30 +00001883
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001884- Added a test script for the curses module. It isn't run automatically;
1885 regrtest.py must be run with '-u curses' to enable it.
1886
Tim Peters84362bc2001-10-19 17:55:30 +00001887Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001888-------
Tim Peters84362bc2001-10-19 17:55:30 +00001889
Barry Warsaw012852b2001-11-16 16:17:27 +00001890Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001891----
Barry Warsaw012852b2001-11-16 16:17:27 +00001892
1893- PythonScript has been moved to unsupported and is slated to be
1894 removed completely in the next release.
1895
1896- It should now be possible to build applets that work on both OS9 and
1897 OSX.
1898
1899- The core is now linked with CoreServices not Carbon; as a side
1900 result, default 8bit encoding on OSX is now ASCII.
1901
1902- Python should now build on OSX 10.1.1
1903
Tim Peters84362bc2001-10-19 17:55:30 +00001904
Tim Petersabf925f2001-09-28 21:53:42 +00001905What's New in Python 2.2b1?
Tim Petersabf925f2001-09-28 21:53:42 +00001906===========================
1907
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001908*Release date: 19-Oct-2001*
1909
Tim Petersabf925f2001-09-28 21:53:42 +00001910Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001911--------------------------------------------
Tim Petersabf925f2001-09-28 21:53:42 +00001912
Guido van Rossum687ae002001-10-15 22:03:32 +00001913- New-style classes are now always dynamic (except for built-in and
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001914 extension types). There is no longer a performance penalty, and I
Guido van Rossum687ae002001-10-15 22:03:32 +00001915 no longer see another reason to keep this baggage around. One relic
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001916 remains: the __dict__ of a new-style class is a read-only proxy; you
1917 must set the class's attribute to modify it. As a consequence, the
Guido van Rossum687ae002001-10-15 22:03:32 +00001918 __defined__ attribute of new-style types no longer exists, for lack
1919 of need: there is once again only one __dict__ (although in the
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001920 future a __cache__ may be resurrected with a similar function, if I
1921 can prove that it actually speeds things up).
Guido van Rossum50fda3b2001-10-04 19:46:06 +00001922
Tim Peters1c9ca872001-10-04 06:43:12 +00001923- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
1924 always returned None, even when there was a class docstring).
1925
1926- doctest now finds and runs docstrings attached to new-style classes,
1927 class methods, static methods, and properties.
1928
Guido van Rossum9074ef62001-10-16 21:34:49 +00001929Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001930-----------------
Tim Petersabf925f2001-09-28 21:53:42 +00001931
Guido van Rossuma8bcf802001-10-15 15:53:58 +00001932- A very subtle syntactical pitfall in list comprehensions was fixed.
1933 For example: [a+b for a in 'abc', for b in 'def']. The comma in
1934 this example is a mistake. Previously, this would silently let 'a'
1935 iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
1936 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
1937 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
1938 Note that [a for a in <singleton>] is a convoluted way to say
1939 [<singleton>] anyway, so it's not like any expressiveness is lost.
1940
Guido van Rossum9074ef62001-10-16 21:34:49 +00001941- getattr(obj, name, default) now only catches AttributeError, as
1942 documented, rather than returning the default value for all
1943 exceptions (which could mask bugs in a __getattr__ hook, for
1944 example).
1945
Fred Drakecb7a6b52001-10-22 18:41:51 +00001946- Weak reference objects are now part of the core and offer a C API.
Fred Drake934d2a42001-10-18 18:18:06 +00001947 A bug which could allow a core dump when binary operations involved
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001948 proxy reference has been fixed. weakref.ReferenceError is now a
Barry Warsawf6fb1712001-10-19 05:35:40 +00001949 built-in exception.
Fred Drake934d2a42001-10-18 18:18:06 +00001950
Guido van Rossum1c486092001-10-19 02:05:35 +00001951- unicode(obj) now behaves more like str(obj), accepting arbitrary
1952 objects, and calling a __unicode__ method if it exists.
1953 unicode(obj, encoding) and unicode(obj, encoding, errors) still
Marc-André Lemburgb5507ec2001-10-19 12:02:29 +00001954 require an 8-bit string or character buffer argument.
Guido van Rossum1c486092001-10-19 02:05:35 +00001955
Barry Warsawf6fb1712001-10-19 05:35:40 +00001956- isinstance() now allows any object as the first argument and a
1957 class, a type or something with a __bases__ tuple attribute for the
1958 second argument. The second argument may also be a tuple of a
1959 class, type, or something with __bases__, in which case isinstance()
1960 will return true if the first argument is an instance of any of the
1961 things contained in the second argument tuple. E.g.
1962
1963 isinstance(x, (A, B))
1964
1965 returns true if x is an instance of A or B.
1966
Guido van Rossum9074ef62001-10-16 21:34:49 +00001967Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001968-----------------
Guido van Rossum9074ef62001-10-16 21:34:49 +00001969
1970- thread.start_new_thread() now returns the thread ID (previously None).
1971
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001972- binascii has now two quopri support functions, a2b_qp and b2a_qp.
1973
Guido van Rossumc524d952001-10-19 01:31:59 +00001974- readline now supports setting the startup_hook and the
1975 pre_event_hook, and adds the add_history() function.
Martin v. Löwis0daad592001-09-30 21:09:59 +00001976
Guido van Rossumc524d952001-10-19 01:31:59 +00001977- os and posix supports chroot(), setgroups() and unsetenv() where
1978 available. The stat(), fstat(), statvfs() and fstatvfs() functions
1979 now return "pseudo-sequences" -- the various fields can now be
1980 accessed as attributes (e.g. os.stat("/").st_mtime) but for
1981 backwards compatibility they also behave as a fixed-length sequence.
1982 Some platform-specific fields (e.g. st_rdev) are only accessible as
Guido van Rossum98bf58f2001-10-18 20:34:25 +00001983 attributes.
1984
1985- time: localtime(), gmtime() and strptime() now return a
1986 pseudo-sequence similar to the os.stat() return value, with
1987 attributes like tm_year etc.
Martin v. Löwis16628c92001-10-04 22:46:41 +00001988
Guido van Rossum9074ef62001-10-16 21:34:49 +00001989- Decompression objects in the zlib module now accept an optional
1990 second parameter to decompress() that specifies the maximum amount
1991 of memory to use for the uncompressed data.
Tim Petersabf925f2001-09-28 21:53:42 +00001992
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001993- optional SSL support in the socket module now exports OpenSSL
1994 functions RAND_add(), RAND_egd(), and RAND_status(). These calls
1995 are useful on platforms like Solaris where OpenSSL does not
Barry Warsawf6fb1712001-10-19 05:35:40 +00001996 automatically seed its PRNG. Also, the keyfile and certfile
1997 arguments to socket.ssl() are now optional.
1998
1999- posixmodule (and by extension, the os module on POSIX platforms) now
2000 exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
Jeremy Hyltoncb441432001-10-19 03:40:19 +00002001
Guido van Rossum9074ef62001-10-16 21:34:49 +00002002Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002003-------
Guido van Rossum3c288632001-10-16 21:13:49 +00002004
Tim Peters7402f792001-10-02 03:53:41 +00002005- doctest now excludes functions and classes not defined by the module
2006 being tested, thanks to Tim Hochberg.
2007
Fred Drakecb7a6b52001-10-22 18:41:51 +00002008- HotShot, a new profiler implemented using a C-based callback, has
2009 been added. This substantially reduces the overhead of profiling,
2010 but it is still quite preliminary. Support modules and
2011 documentation will be added in upcoming releases (before 2.2 final).
2012
Guido van Rossumc4b09b42001-10-04 10:19:00 +00002013- profile now produces correct output in situations where an exception
2014 raised in Python is cleared by C code (e.g. hasattr()). This used
2015 to cause wrong output, including spurious claims of recursive
2016 functions and attribution of time spent to the wrong function.
2017
Tim Peters0a1fc4e2001-10-07 03:12:08 +00002018 The code and documentation for the derived OldProfile and HotProfile
2019 profiling classes was removed. The code hasn't worked for years (if
2020 you tried to use them, they raised exceptions). OldProfile
2021 intended to reproduce the behavior of the profiler Python used more
2022 than 7 years ago, and isn't interesting anymore. HotProfile intended
2023 to provide a faster profiler (but producing less information), and
2024 that's a worthy goal we intend to meet via a different approach (but
2025 without losing information).
2026
Tim Peterscce092d2001-10-09 05:31:56 +00002027- Profile.calibrate() has a new implementation that should deliver
Tim Peters659a6032001-10-09 20:51:19 +00002028 a much better system-specific calibration constant. The constant can
2029 now be specified in an instance constructor, or as a Profile class or
2030 instance variable, instead of by editing profile.py's source code.
2031 Calibration must still be done manually (see the docs for the profile
2032 module).
2033
2034 Note that Profile.calibrate() must be overriden by subclasses.
2035 Improving the accuracy required exploiting detailed knowledge of
2036 profiler internals; the earlier method abstracted away the details
2037 and measured a simplified model instead, but consequently computed
2038 a constant too small by a factor of 2 on some modern machines.
Tim Peterscce092d2001-10-09 05:31:56 +00002039
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00002040- quopri's encode and decode methods take an optional header parameter,
Jeremy Hylton6f543b62001-10-16 20:42:52 +00002041 which indicates whether output is intended for the header 'Q'
2042 encoding.
2043
Guido van Rossuma5343cc2001-10-18 18:02:07 +00002044- The SocketServer.ThreadingMixIn class now closes the request after
2045 finish_request() returns. (Not when it errors out though.)
2046
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002047- The nntplib module's NNTP.body() method has grown a 'file' argument
Barry Warsawf6fb1712001-10-19 05:35:40 +00002048 to allow saving the message body to a file.
2049
2050- The email package has added a class email.Parser.HeaderParser which
2051 only parses headers and does not recurse into the message's body.
2052 Also, the module/class MIMEAudio has been added for representing
2053 audio data (contributed by Anthony Baxter).
2054
2055- ftplib should be able to handle files > 2GB.
2056
2057- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
2058 ON, and OFF.
2059
Fred Drakecb7a6b52001-10-22 18:41:51 +00002060- xml.dom.minidom NodeList objects now support the length attribute
2061 and item() method as required by the DOM specifications.
2062
Guido van Rossumed554f62001-10-02 23:15:37 +00002063Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002064-----------
Guido van Rossumed554f62001-10-02 23:15:37 +00002065
2066- Demo/dns was removed. It no longer serves any purpose; a package
2067 derived from it is now maintained by Anthony Baxter, see
2068 http://PyDNS.SourceForge.net.
Tim Petersabf925f2001-09-28 21:53:42 +00002069
Barry Warsawf6fb1712001-10-19 05:35:40 +00002070- The freeze tool has been made more robust, and two new options have
2071 been added: -X and -E.
2072
Tim Petersabf925f2001-09-28 21:53:42 +00002073Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002074-----
Tim Petersabf925f2001-09-28 21:53:42 +00002075
Barry Warsawf6fb1712001-10-19 05:35:40 +00002076- configure will use CXX in LINKCC if CXX is used to build main() and
2077 the system requires to link a C++ main using the C++ compiler.
2078
Tim Petersabf925f2001-09-28 21:53:42 +00002079C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002080-----
Tim Petersabf925f2001-09-28 21:53:42 +00002081
Guido van Rossum6c4bce32001-10-18 19:20:25 +00002082- The documentation for the tp_compare slot is updated to require that
2083 the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
2084 not correct. This is not yet enforced but will be enforced in
2085 Python 2.3; even later, we may use -2 to indicate errors and +2 for
2086 "NotImplemented". Right now, -1 should be used for an error return.
2087
Tim Petersd38b1c72001-09-30 05:09:37 +00002088- PyLong_AsLongLong() now accepts int (as well as long) arguments.
2089 Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
2090 as long) arguments.
2091
Guido van Rossum3c288632001-10-16 21:13:49 +00002092- PyThread_start_new_thread() now returns a long int giving the thread
2093 ID, if one can be calculated; it returns -1 for error, 0 if no
2094 thread ID is calculated (this is an incompatible change, but only
2095 the thread module used this API). This code has only really been
2096 tested on Linux and Windows; other platforms please beware (and
2097 report any bugs or strange behavior).
2098
Guido van Rossum1c486092001-10-19 02:05:35 +00002099- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
2100 input.
2101
Tim Petersabf925f2001-09-28 21:53:42 +00002102New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002103-------------
Tim Petersabf925f2001-09-28 21:53:42 +00002104
2105Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002106-----
Tim Petersabf925f2001-09-28 21:53:42 +00002107
2108Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002109-------
Tim Petersabf925f2001-09-28 21:53:42 +00002110
Tim Peters04cf1d32001-10-09 22:39:40 +00002111- Installer: If you install IDLE, and don't disable file-extension
2112 registration, a new "Edit with IDLE" context (right-click) menu entry
2113 is created for .py and .pyw files.
2114
Tim Peters1ce3cf72001-10-01 17:58:40 +00002115- The signal module now supports SIGBREAK on Windows, thanks to Steven
2116 Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
2117 action remains to call Win32 ExitProcess(). This can be changed via
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002118 signal.signal(). For example::
Tim Peters1ce3cf72001-10-01 17:58:40 +00002119
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002120 # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
2121 # (SIGINT) behavior.
2122 import signal
2123 signal.signal(signal.SIGBREAK, signal.default_int_handler)
Tim Peters1ce3cf72001-10-01 17:58:40 +00002124
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002125 try:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002126 while 1:
2127 pass
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002128 except KeyboardInterrupt:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002129 # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
2130 # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
2131 # program without the possibility for any Python-level cleanup).
2132 print "Clean exit"
Tim Peters1ce3cf72001-10-01 17:58:40 +00002133
Tim Petersabf925f2001-09-28 21:53:42 +00002134
Tim Petersb07352e2001-09-08 01:25:47 +00002135What's New in Python 2.2a4?
2136===========================
2137
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002138*Release date: 28-Sep-2001*
2139
Guido van Rossum808eea72001-09-25 04:15:41 +00002140Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002141--------------------------------------------
Guido van Rossum808eea72001-09-25 04:15:41 +00002142
2143- pydoc and inspect are now aware of new-style classes;
2144 e.g. help(list) at the interactive prompt now shows proper
2145 documentation for all operations on list objects.
2146
2147- Applications using Jim Fulton's ExtensionClass module can now safely
2148 be used with Python 2.2. In particular, Zope 2.4.1 now works with
2149 Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
2150 examples also work again. It is hoped that Gtk and Boost also work
2151 with 2.2a4 and beyond. (If you can confirm this, please write
2152 webmaster@python.org; if there are still problems, please open a bug
2153 report on SourceForge.)
Tim Petersb07352e2001-09-08 01:25:47 +00002154
Tim Peters66c1a522001-09-24 21:17:50 +00002155- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00002156 These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
Tim Peters66c1a522001-09-24 21:17:50 +00002157 in the constructed property object. fget, fset and fdel weren't
2158 discoverable from Python in 2.2a3. __doc__ is new, and allows to
2159 associate a docstring with a property.
2160
Guido van Rossum808eea72001-09-25 04:15:41 +00002161- Comparison overloading is now more completely implemented. For
2162 example, a str subclass instance can properly be compared to a str
2163 instance, and it can properly overload comparison. Ditto for most
2164 other built-in object types.
2165
2166- The repr() of new-style classes has changed; instead of <type
2167 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
2168 *except* for built-in types, which are still rendered as <type
2169 'Foo'> (to avoid upsetting existing code that might parse or
2170 otherwise rely on repr() of certain type objects).
2171
2172- The repr() of new-style objects is now always <Foo object at XXX>;
2173 previously, it was sometimes <Foo instance at XXX>.
2174
2175- For new-style classes, what was previously called __getattr__ is now
2176 called __getattribute__. This method, if defined, is called for
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00002177 *every* attribute access. A new __getattr__ hook more similar to the
Guido van Rossum808eea72001-09-25 04:15:41 +00002178 one in classic classes is defined which is called only if regular
2179 attribute access raises AttributeError; to catch *all* attribute
2180 access, you can use __getattribute__ (for new-style classes). If
2181 both are defined, __getattribute__ is called first, and if it raises
2182 AttributeError, __getattr__ is called.
2183
2184- The __class__ attribute of new-style objects can be assigned to.
2185 The new class must have the same C-level object layout as the old
2186 class.
2187
2188- The builtin file type can be subclassed now. In the usual pattern,
2189 "file" is the name of the builtin type, and file() is a new builtin
2190 constructor, with the same signature as the builtin open() function.
2191 file() is now the preferred way to open a file.
2192
2193- Previously, __new__ would only see sequential arguments passed to
2194 the type in a constructor call; __init__ would see both sequential
2195 and keyword arguments. This made no sense whatsoever any more, so
2196 now both __new__ and __init__ see all arguments.
2197
2198- Previously, hash() applied to an instance of a subclass of str or
2199 unicode always returned 0. This has been repaired.
2200
2201- Previously, an operation on an instance of a subclass of an
2202 immutable type (int, long, float, complex, tuple, str, unicode),
2203 where the subtype didn't override the operation (and so the
2204 operation was handled by the builtin type), could return that
2205 instance instead a value of the base type. For example, if s was of
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00002206 a str subclass type, s[:] returned s as-is. Now it returns a str
Guido van Rossum808eea72001-09-25 04:15:41 +00002207 with the same value as s.
2208
Barry Warsaw86fbaf82001-09-28 15:26:12 +00002209- Provisional support for pickling new-style objects has been added.
2210
Guido van Rossum808eea72001-09-25 04:15:41 +00002211Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002212----
Guido van Rossum808eea72001-09-25 04:15:41 +00002213
Tim Peters2c9aa5e2001-09-23 04:06:05 +00002214- file.writelines() now accepts any iterable object producing strings.
2215
Marc-André Lemburgaefd7662001-09-20 12:59:37 +00002216- PyUnicode_FromEncodedObject() now works very much like
2217 PyObject_Str(obj) in that it tries to use __str__/tp_str
2218 on the object if the object is not a string or buffer. This
2219 makes unicode() behave like str() when applied to non-string/buffer
2220 objects.
2221
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00002222- PyFile_WriteObject now passes Unicode objects to the file's write
2223 method. As a result, all file-like objects which may be the target
Martin v. Löwis2777c022001-09-19 13:47:32 +00002224 of a print statement must support Unicode objects, i.e. they must
2225 at least convert them into ASCII strings.
2226
Guido van Rossum624c8af2001-09-18 15:21:04 +00002227- Thread scheduling on Solaris should be improved; it is no longer
2228 necessary to insert a small sleep at the start of a thread in order
2229 to let other runnable threads be scheduled.
2230
Tim Petersb07352e2001-09-08 01:25:47 +00002231Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002232-------
Tim Petersb07352e2001-09-08 01:25:47 +00002233
Marc-André Lemburgbf990172001-09-27 14:17:33 +00002234- StringIO.StringIO instances and cStringIO.StringIO instances support
2235 read character buffer compatible objects for their .write() methods.
2236 These objects are converted to strings and then handled as such
2237 by the instances.
2238
Barry Warsaw2f600732001-09-24 04:28:10 +00002239- The "email" package has been added. This is basically a port of the
2240 mimelib package <http://sf.net/projects/mimelib> with API changes
2241 and some implementations updated to use iterators and generators.
2242
Tim Peters8a9c2842001-09-22 21:30:22 +00002243- difflib.ndiff() and difflib.Differ.compare() are generators now. This
2244 restores the ability of Tools/scripts/ndiff.py to start producing output
2245 before the entire comparison is complete.
2246
Barry Warsaw58b072d2001-09-22 04:44:21 +00002247- StringIO.StringIO instances and cStringIO.StringIO instances support
2248 iteration just like file objects (i.e. their .readline() method is
2249 called for each iteration until it returns an empty string).
2250
Marc-André Lemburg494f2ae2001-09-19 11:33:31 +00002251- The codecs module has grown four new helper APIs to access
2252 builtin codecs: getencoder(), getdecoder(), getreader(),
2253 getwriter().
2254
Guido van Rossum624c8af2001-09-18 15:21:04 +00002255- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
2256 simplifies writing XML RPC servers.
2257
Barry Warsaw647d5e82001-09-28 17:01:02 +00002258- os.path.realpath(): a new function that returns the absolute pathname
Guido van Rossum624c8af2001-09-18 15:21:04 +00002259 after interpretation of symbolic links. On non-Unix systems, this
2260 is an alias for os.path.abspath().
2261
Tim Peters16a77ad2001-09-08 04:00:12 +00002262- operator.indexOf() (PySequence_Index() in the C API) now works with any
2263 iterable object.
2264
Guido van Rossum624c8af2001-09-18 15:21:04 +00002265- smtplib now supports various authentication and security features of
2266 the SMTP protocol through the new login() and starttls() methods.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00002267
Guido van Rossum624c8af2001-09-18 15:21:04 +00002268- hmac: a new module implementing keyed hashing for message
2269 authentication.
2270
2271- mimetypes now recognizes more extensions and file types. At the
2272 same time, some mappings not sanctioned by IANA were removed.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00002273
Guido van Rossum624c8af2001-09-18 15:21:04 +00002274- The "compiler" package has been brought up to date to the state of
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00002275 Python 2.2 bytecode generation. It has also been promoted from a
2276 Tool to a standard library package. (Tools/compiler still exists as
2277 a sample driver.)
2278
Tim Petersb07352e2001-09-08 01:25:47 +00002279Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002280-----
Tim Petersb07352e2001-09-08 01:25:47 +00002281
Guido van Rossum624c8af2001-09-18 15:21:04 +00002282- Large file support (LFS) is now automatic when the platform supports
2283 it; no more manual configuration tweaks are needed. On Linux, at
2284 least, it's possible to have a system whose C library supports large
2285 files but whose kernel doesn't; in this case, large file support is
2286 still enabled but doesn't do you any good unless you upgrade your
2287 kernel or share your Python executable with another system whose
2288 kernel has large file support.
2289
2290- The configure script now supplies plausible defaults in a
2291 cross-compilation environment. This doesn't mean that the supplied
2292 values are always correct, or that cross-compilation now works
2293 flawlessly -- but it's a first step (and it shuts up most of
2294 autoconf's warnings about AC_TRY_RUN).
2295
2296- The Unix build is now a bit less chatty, courtesy of the parser
2297 generator. The build is completely silent (except for errors) when
2298 using "make -s", thanks to a -q option to setup.py.
2299
Tim Petersb07352e2001-09-08 01:25:47 +00002300C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002301-----
Tim Petersb07352e2001-09-08 01:25:47 +00002302
Guido van Rossum624c8af2001-09-18 15:21:04 +00002303- The "structmember" API now supports some new flag bits to deny read
2304 and/or write access to attributes in restricted execution mode.
2305
Tim Petersb07352e2001-09-08 01:25:47 +00002306New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002307-------------
Tim Petersb07352e2001-09-08 01:25:47 +00002308
Guido van Rossum624c8af2001-09-18 15:21:04 +00002309- Compaq's iPAQ handheld, running the "familiar" Linux distribution
2310 (http://familiar.handhelds.org).
2311
Tim Petersb07352e2001-09-08 01:25:47 +00002312Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002313-----
Tim Petersb07352e2001-09-08 01:25:47 +00002314
Tim Peters8a9c2842001-09-22 21:30:22 +00002315- The "classic" standard tests, which work by comparing stdout to
2316 an expected-output file under Lib/test/output/, no longer stop at
2317 the first mismatch. Instead the test is run to completion, and a
2318 variant of ndiff-style comparison is used to report all differences.
2319 This is much easier to understand than the previous style of reporting.
2320
2321- The unittest-based standard tests now use regrtest's test_main()
2322 convention, instead of running as a side-effect of merely being
2323 imported. This allows these tests to be run in more natural and
2324 flexible ways as unittests, outside the regrtest framework.
2325
2326- regrtest.py is much better integrated with unittest and doctest now,
2327 especially in regard to reporting errors.
2328
Tim Petersb07352e2001-09-08 01:25:47 +00002329Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002330-------
Tim Petersb07352e2001-09-08 01:25:47 +00002331
Guido van Rossum624c8af2001-09-18 15:21:04 +00002332- Large file support now also works for files > 4GB, on filesystems
Tim Peters8a9c2842001-09-22 21:30:22 +00002333 that support it (NTFS under Windows 2000). See "What's New in
2334 Python 2.2a3" for more detail.
Guido van Rossum624c8af2001-09-18 15:21:04 +00002335
Tim Petersb07352e2001-09-08 01:25:47 +00002336
Tim Petersedc99312001-08-22 21:36:50 +00002337What's New in Python 2.2a3?
2338===========================
2339
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002340*Release Date: 07-Sep-2001*
2341
Tim Petersedc99312001-08-22 21:36:50 +00002342Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002343----
Tim Petersedc99312001-08-22 21:36:50 +00002344
Tim Peters9fffa3e2001-09-04 05:14:19 +00002345- Conversion of long to float now raises OverflowError if the long is too
2346 big to represent as a C double.
2347
Tim Peters32f453e2001-09-03 08:35:41 +00002348- The 3-argument builtin pow() no longer allows a third non-None argument
2349 if either of the first two arguments is a float, or if both are of
2350 integer types and the second argument is negative (in which latter case
2351 the arguments are converted to float, so this is really the same
2352 restriction).
2353
Tim Peters5d2b77c2001-09-03 05:47:38 +00002354- The builtin dir() now returns more information, and sometimes much
2355 more, generally naming all attributes of an object, and all attributes
2356 reachable from the object via its class, and from its class's base
2357 classes, and so on from them too. Example: in 2.2a2, dir([]) returned
2358 an empty list. In 2.2a3,
2359
2360 >>> dir([])
2361 ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
2362 '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
2363 '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
2364 '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
2365 '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
2366 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
2367 'reverse', 'sort']
2368
2369 dir(module) continues to return only the module's attributes, though.
2370
Tim Petersbdee63f2001-09-02 03:40:59 +00002371- Overflowing operations on plain ints now return a long int rather
Guido van Rossumae457142001-08-31 18:31:35 +00002372 than raising OverflowError. This is a partial implementation of PEP
2373 237. You can use -Wdefault::OverflowWarning to enable a warning for
2374 this situation, and -Werror::OverflowWarning to revert to the old
2375 OverflowError exception.
2376
Guido van Rossum61c345f2001-09-04 03:26:15 +00002377- A new command line option, -Q<arg>, is added to control run-time
Guido van Rossumae457142001-08-31 18:31:35 +00002378 warnings for the use of classic division. (See PEP 238.) Possible
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002379 values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
2380 -Qold, meaning the / operator has its classic meaning and no
2381 warnings are issued. Using -Qwarn issues a run-time warning about
2382 all uses of classic division for int and long arguments; -Qwarnall
2383 also warns about classic division for float and complex arguments
Tim Peters3caca232001-12-06 06:23:26 +00002384 (for use with fixdiv.py).
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002385 [Note: the remainder of this item (preserved below) became
2386 obsolete in 2.2c1 -- -Qnew has global effect in 2.2] ::
2387
2388 Using -Qnew is questionable; it turns on new division by default, but
2389 only in the __main__ module. You can usefully combine -Qwarn or
2390 -Qwarnall and -Qnew: this gives the __main__ module new division, and
2391 warns about classic division everywhere else.
Guido van Rossumae457142001-08-31 18:31:35 +00002392
Tim Petersbdee63f2001-09-02 03:40:59 +00002393- Many built-in types can now be subclassed. This applies to int,
Guido van Rossumae457142001-08-31 18:31:35 +00002394 long, float, str, unicode, and tuple. (The types complex, list and
2395 dictionary can also be subclassed; this was introduced earlier.)
2396 Note that restrictions apply when subclassing immutable built-in
2397 types: you can only affect the value of the instance by overloading
2398 __new__. You can add mutable attributes, and the subclass instances
2399 will have a __dict__ attribute, but you cannot change the "value"
2400 (as implemented by the base class) of an immutable subclass instance
2401 once it is created.
2402
Guido van Rossumaaf80c82001-09-02 13:44:35 +00002403- The dictionary constructor now takes an optional argument, a
2404 mapping-like object, and initializes the dictionary from its
2405 (key, value) pairs.
2406
Tim Petersbdee63f2001-09-02 03:40:59 +00002407- A new built-in type, super, has been added. This facilitates making
Guido van Rossumae457142001-08-31 18:31:35 +00002408 "cooperative super calls" in a multiple inheritance setting. For an
2409 explanation, see http://www.python.org/2.2/descrintro.html#cooperation
2410
Guido van Rossum8d7234d2001-09-06 22:02:58 +00002411- A new built-in type, property, has been added. This enables the
2412 creation of "properties". These are attributes implemented by
2413 getter and setter functions (or only one of these for read-only or
2414 write-only attributes), without the need to override __getattr__.
2415 See http://www.python.org/2.2/descrintro.html#property
Guido van Rossumae457142001-08-31 18:31:35 +00002416
Tim Petersbdee63f2001-09-02 03:40:59 +00002417- The syntax of floating-point and imaginary literals has been
Tim Petersd507dab2001-08-30 20:51:59 +00002418 liberalized, to allow leading zeroes. Examples of literals now
2419 legal that were SyntaxErrors before:
2420
2421 00.0 0e3 0100j 07.5 00000000000000000008.
2422
Tim Petersbdee63f2001-09-02 03:40:59 +00002423- An old tokenizer bug allowed floating point literals with an incomplete
Tim Petersc6d95812001-08-28 20:56:27 +00002424 exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
2425
Tim Petersedc99312001-08-22 21:36:50 +00002426Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002427-------
Tim Petersedc99312001-08-22 21:36:50 +00002428
Martin v. Löwiscb227c92001-09-06 08:54:16 +00002429- telnetlib includes symbolic names for the options, and support for
Martin v. Löwis1da9c572002-11-04 09:56:00 +00002430 setting an option negotiation callback. It also supports processing
2431 of suboptions.
Martin v. Löwiscb227c92001-09-06 08:54:16 +00002432
Tim Petersa40c7932001-09-05 22:36:56 +00002433- The new C standard no longer requires that math libraries set errno to
2434 ERANGE on overflow. For platform libraries that exploit this new
2435 freedom, Python's overflow-checking was wholly broken. A new overflow-
2436 checking scheme attempts to repair that, but may not be reliable on all
2437 platforms (C doesn't seem to provide anything both useful and portable
2438 in this area anymore).
2439
Martin v. Löwis44f86962001-09-05 13:44:54 +00002440- Asynchronous timeout actions are available through the new class
2441 threading.Timer.
2442
Tim Peters78526162001-09-05 00:53:45 +00002443- math.log and math.log10 now return sensible results for even huge
2444 long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
2445
Tim Petersbdee63f2001-09-02 03:40:59 +00002446- A new function, imp.lock_held(), returns 1 when the import lock is
Tim Peters69232342001-08-30 05:16:13 +00002447 currently held. See the docs for the imp module.
2448
Tim Petersbdee63f2001-09-02 03:40:59 +00002449- pickle, cPickle and marshal on 32-bit platforms can now correctly read
Tim Peters82112372001-08-29 02:28:42 +00002450 dumps containing ints written on platforms where Python ints are 8 bytes.
2451 When read on a box where Python ints are 4 bytes, such values are
2452 converted to Python longs.
2453
Tim Petersbdee63f2001-09-02 03:40:59 +00002454- In restricted execution mode (using the rexec module), unmarshalling
Guido van Rossumae457142001-08-31 18:31:35 +00002455 code objects is no longer allowed. This plugs a security hole.
2456
Steve Purcell6091cd62001-09-06 16:05:17 +00002457- unittest.TestResult instances no longer store references to tracebacks
2458 generated by test failures. This prevents unexpected dangling references
2459 to objects that should be garbage collected between tests.
2460
Tim Petersedc99312001-08-22 21:36:50 +00002461Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002462-----
Tim Petersedc99312001-08-22 21:36:50 +00002463
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002464- Tools/scripts/fixdiv.py has been added which can be used to fix
2465 division operators as per PEP 238.
2466
Tim Petersedc99312001-08-22 21:36:50 +00002467Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002468-----
Tim Petersedc99312001-08-22 21:36:50 +00002469
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002470- If you are an adventurous person using Mac OS X you may want to look at
2471 Mac/OSX. There is a Makefile there that will build Python as a real Mac
2472 application, which can be used for experimenting with Carbon or Cocoa.
2473 Discussion of this on pythonmac-sig, please.
2474
Tim Peters7eea37e2001-09-04 22:08:56 +00002475C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002476-----
Tim Peters7eea37e2001-09-04 22:08:56 +00002477
2478- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
Tim Peters69232342001-08-30 05:16:13 +00002479
Tim Peters9fffa3e2001-09-04 05:14:19 +00002480- Note that PyLong_AsDouble can fail! This has always been true, but no
2481 callers checked for it. It's more likely to fail now, because overflow
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002482 errors are properly detected now. The proper way to check::
Tim Peters9fffa3e2001-09-04 05:14:19 +00002483
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002484 double x = PyLong_AsDouble(some_long_object);
2485 if (x == -1.0 && PyErr_Occurred()) {
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002486 /* The conversion failed. */
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002487 }
Tim Peters9fffa3e2001-09-04 05:14:19 +00002488
Tim Petersbdee63f2001-09-02 03:40:59 +00002489- The GC API has been changed. Extensions that use the old API will still
Neil Schemenauer4042c692001-08-30 15:38:01 +00002490 compile but will not participate in GC. To upgrade an extension
2491 module:
2492
2493 - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
Tim Petersd507dab2001-08-30 20:51:59 +00002494
Neil Schemenauer4042c692001-08-30 15:38:01 +00002495 - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
2496 PyObject_GC_Del to deallocate them
Tim Petersd507dab2001-08-30 20:51:59 +00002497
Neil Schemenauer4042c692001-08-30 15:38:01 +00002498 - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
2499 to PyObject_GC_UnTrack
Tim Petersd507dab2001-08-30 20:51:59 +00002500
Neil Schemenauer4042c692001-08-30 15:38:01 +00002501 - remove PyGC_HEAD_SIZE from object size calculations
2502
2503 - remove calls to PyObject_AS_GC and PyObject_FROM_GC
2504
Tim Petersbdee63f2001-09-02 03:40:59 +00002505- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
Guido van Rossumae457142001-08-31 18:31:35 +00002506 These can be used safely to construct string objects from a
2507 sprintf-style format string (similar to the format string supported
2508 by PyErr_Format()).
Tim Peters69232342001-08-30 05:16:13 +00002509
Tim Petersedc99312001-08-22 21:36:50 +00002510New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002511-------------
Tim Petersedc99312001-08-22 21:36:50 +00002512
Tim Petersb7da0902001-09-02 23:01:43 +00002513- Stephen Hansen contributed patches sufficient to get a clean compile
2514 under Borland C (Windows), but he reports problems running it and ran
2515 out of time to complete the port. Volunteers? Expect a MemoryError
2516 when importing the types module; this is probably shallow, and
2517 causing later failures too.
Tim Petersbdee63f2001-09-02 03:40:59 +00002518
Tim Petersedc99312001-08-22 21:36:50 +00002519Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002520-----
Tim Petersedc99312001-08-22 21:36:50 +00002521
2522Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002523-------
Tim Petersedc99312001-08-22 21:36:50 +00002524
Tim Peters6e13a562001-09-06 00:32:15 +00002525- Large file support is now enabled on Win32 platforms as well as on
2526 Win64. This means that, for example, you can use f.tell() and f.seek()
2527 to manipulate files larger than 2 gigabytes (provided you have enough
2528 disk space, and are using a Windows filesystem that supports large
Tim Peters9a9471c2001-09-11 23:18:51 +00002529 partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
2530 filesize limit, and large file support makes no difference there.
2531 FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
2532 NTFS has no practical limit on file size, and files of any size can be
2533 used from Python now.
Tim Peters6e13a562001-09-06 00:32:15 +00002534
Tim Petersbdee63f2001-09-02 03:40:59 +00002535- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
Tim Peters402d5982001-08-27 06:37:48 +00002536 points to command.com (patch from Brian Quinlan).
2537
Tim Petersedc99312001-08-22 21:36:50 +00002538
Tim Peters20f51a72001-07-21 02:31:40 +00002539What's New in Python 2.2a2?
2540===========================
2541
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002542*Release Date: 22-Aug-2001*
2543
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002544Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002545-----
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002546
Barry Warsaw18b2ecf2001-08-22 20:26:56 +00002547- Tim Peters developed a brand new Windows installer using Wise 8.1,
2548 generously donated to us by Wise Solutions.
2549
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002550- configure supports a new option --enable-unicode, with the values
2551 ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
2552 type and supporting code is completely removed from the interpreter.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002553
Jack Jansen32ce0cd2001-08-21 19:28:20 +00002554- A new configure option --enable-framework builds a Mac OS X framework,
2555 which "make frameworkinstall" will install. This provides a starting
2556 point for more mac-like functionality, join pythonmac-sig@python.org
2557 if you are interested in helping.
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002558
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002559- The NeXT platform is no longer supported.
2560
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002561- The 'new' module is now statically linked.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002562
Tim Peters0afb6092001-08-15 06:06:44 +00002563Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002564-----
Tim Peters0afb6092001-08-15 06:06:44 +00002565
2566- The new Tools/scripts/cleanfuture.py can be used to automatically
Andrew M. Kuchlingb0532092001-08-15 15:54:56 +00002567 edit out obsolete future statements from Python source code. See
Tim Peters0afb6092001-08-15 06:06:44 +00002568 the module docstring for details.
2569
Tim Peters20f51a72001-07-21 02:31:40 +00002570Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002571-----
Tim Peters20f51a72001-07-21 02:31:40 +00002572
Tim Peters5e824c32001-08-12 22:25:01 +00002573- regrtest.py now knows which tests are expected to be skipped on some
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002574 platforms, allowing to give clearer test result output. regrtest
2575 also has optional --use/-u switch to run normally disabled tests
2576 which require network access or consume significant disk resources.
Tim Peters5e824c32001-08-12 22:25:01 +00002577
Tim Peters20f51a72001-07-21 02:31:40 +00002578- Several new tests in the standard test suite, with special thanks to
2579 Nick Mathewson.
2580
2581Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002582----
Tim Peters20f51a72001-07-21 02:31:40 +00002583
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002584- The floor division operator // has been added as outlined in PEP
2585 238. The / operator still provides classic division (and will until
2586 Python 3.0) unless "from __future__ import division" is included, in
2587 which case the / operator will provide true division. The operator
2588 module provides truediv() and floordiv() functions. Augmented
2589 assignment variants are included, as are the equivalent overloadable
2590 methods and C API methods. See the PEP for a full discussion:
2591 <http://python.sf.net/peps/pep-0238.html>
2592
Tim Peters6cd6a822001-08-17 22:11:27 +00002593- Future statements are now effective in simulated interactive shells
2594 (like IDLE). This should "just work" by magic, but read Michael
2595 Hudson's "Future statements in simulated shells" PEP 264 for full
2596 details: <http://python.sf.net/peps/pep-0264.html>.
2597
Guido van Rossumf86ddd22001-08-17 21:21:04 +00002598- The type/class unification (PEP 252-253) was integrated into the
2599 trunk and is not so tentative any more (the exact specification of
2600 some features is still tentative). A lot of work has done on fixing
2601 bugs and adding robustness and features (performance still has to
2602 come a long way).
2603
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002604- Warnings about a mismatch in the Python API during extension import
2605 now use the Python warning framework (which makes it possible to
2606 write filters for these warnings).
2607
Barry Warsaw9b3be7f2001-08-14 18:35:02 +00002608- A function's __dict__ (aka func_dict) will now always be a
2609 dictionary. It used to be possible to delete it or set it to None,
2610 but now both actions raise TypeErrors. It is still legal to set it
2611 to a dictionary object. Getting func.__dict__ before any attributes
2612 have been assigned now returns an empty dictionary instead of None.
2613
Guido van Rossum32aa5d22001-09-05 18:43:35 +00002614- A new command line option, -E, was added which disables the use of
2615 all environment variables, or at least those that are specifically
2616 significant to Python. Usually those have a name starting with
2617 "PYTHON". This was used to fix a problem where the tests fail if
2618 the user happens to have PYTHONHOME or PYTHONPATH pointing to an
2619 older distribution.
2620
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002621Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002622-------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002623
Tim Peters5e824c32001-08-12 22:25:01 +00002624- New class Differ and new functions ndiff() and restore() in difflib.py.
2625 These package the algorithms used by the popular Tools/scripts/ndiff.py,
Tim Peters0afb6092001-08-15 06:06:44 +00002626 for programmatic reuse.
Tim Peters5e824c32001-08-12 22:25:01 +00002627
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002628- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
2629 value using the minimal quoting required for the value; more
2630 reliable than using xml.sax.saxutils.escape() for attribute values.
2631
2632- Readline completion support for cmd.Cmd was added.
2633
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002634- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
2635
2636- Added function threading.BoundedSemaphore()
2637
2638- Added Ka-Ping Yee's cgitb.py module.
2639
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002640- The 'new' module now exposes the CO_xxx flags.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002641
Martin v. Löwis560da622001-11-24 09:24:51 +00002642- The gc module offers the get_referents function.
2643
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002644New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002645-------------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002646
2647C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002648-----
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002649
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002650- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
2651 which provide a cross-platform implementations for the
2652 relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
2653 the standard sprintf() and vsprintf() C lib APIs, these versions
2654 apply bounds checking on the used buffer which enhances protection
2655 against buffer overruns.
2656
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002657- Unicode APIs now use name mangling to assure that mixing interpreters
Tim Petersc1731372001-08-04 08:12:36 +00002658 and extensions using different Unicode widths is rendered next to
2659 impossible. Trying to import an incompatible Unicode-aware extension
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002660 will result in an ImportError. Unicode extensions writers must make
2661 sure to check the Unicode width compatibility in their extensions by
2662 using at least one of the mangled Unicode APIs in the extension.
2663
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002664- Two new flags METH_NOARGS and METH_O are available in method definition
2665 tables to simplify implementation of methods with no arguments and a
2666 single untyped argument. Calling such methods is more efficient than
2667 calling corresponding METH_VARARGS methods. METH_OLDARGS is now
2668 deprecated.
2669
Tim Petersc1731372001-08-04 08:12:36 +00002670Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002671-------
Tim Petersc1731372001-08-04 08:12:36 +00002672
2673- "import module" now compiles module.pyw if it exists and nothing else
2674 relevant is found.
2675
Tim Peters20f51a72001-07-21 02:31:40 +00002676
Guido van Rossum55a78992001-07-17 17:22:32 +00002677What's New in Python 2.2a1?
Tim Petersf553f892001-05-01 20:45:31 +00002678===========================
2679
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002680*Release date: 18-Jul-2001*
2681
Tim Petersf553f892001-05-01 20:45:31 +00002682Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002683----
Tim Petersa814db52001-05-14 07:05:58 +00002684
Tim Peters6d6c1a32001-08-02 04:15:00 +00002685- TENTATIVELY, a large amount of code implementing much of what's
2686 described in PEP 252 (Making Types Look More Like Classes) and PEP
2687 253 (Subtyping Built-in Types) was added. This will be released
2688 with Python 2.2a1. Documentation will be provided separately
2689 through http://www.python.org/2.2/. The purpose of releasing this
2690 with Python 2.2a1 is to test backwards compatibility. It is
2691 possible, though not likely, that a decision is made not to release
2692 this code as part of 2.2 final, if any serious backwards
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002693 incompatibilities are found during alpha testing that cannot be
Tim Peters6d6c1a32001-08-02 04:15:00 +00002694 repaired.
2695
Guido van Rossum55a78992001-07-17 17:22:32 +00002696- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +00002697 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +00002698 more 'yield' statements. See PEP 255. Since this adds a new
2699 keyword to the language, this feature must be enabled by including a
2700 future statement: "from __future__ import generators" (see PEP 236).
2701 Generators will become a standard feature in a future release
2702 (probably 2.3). Without this future statement, 'yield' remains an
2703 ordinary identifier, but a warning is issued each time it is used.
2704 (These warnings currently don't conform to the warnings framework of
2705 PEP 230; we intend to fix this in 2.2a2.)
2706
Marc-André Lemburg12e74b32001-05-22 08:58:23 +00002707- The UTF-16 codec was modified to be more RFC compliant. It will now
2708 only remove BOM characters at the start of the string and then
2709 only if running in native mode (UTF-16-LE and -BE won't remove a
2710 leading BMO character).
2711
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002712- Strings now have a new method .decode() to complement the already
2713 existing .encode() method. These two methods provide direct access
2714 to the corresponding decoders and encoders of the registered codecs.
2715
2716 To enhance the usability of the .encode() method, the special
2717 casing of Unicode object return values was dropped (Unicode objects
2718 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +00002719
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002720 Both methods will now return whatever the codec in charge of the
2721 requested encoding returns as object, e.g. Unicode codecs will
2722 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
2723 will return u"äöü"). This enables codec writer to create codecs
2724 for various simple to use conversions.
2725
2726 New codecs were added to demonstrate these new features (the .encode()
2727 and .decode() columns indicate the type of the returned objects):
2728
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002729 +---------+-----------+-----------+-----------------------------+
2730 |Name | .encode() | .decode() | Description |
2731 +=========+===========+===========+=============================+
2732 |uu | string | string | UU codec (e.g. for email) |
2733 +---------+-----------+-----------+-----------------------------+
2734 |base64 | string | string | base64 codec |
2735 +---------+-----------+-----------+-----------------------------+
2736 |quopri | string | string | quoted-printable codec |
2737 +---------+-----------+-----------+-----------------------------+
2738 |zlib | string | string | zlib compression |
2739 +---------+-----------+-----------+-----------------------------+
2740 |hex | string | string | 2-byte hex codec |
2741 +---------+-----------+-----------+-----------------------------+
2742 |rot-13 | string | Unicode | ROT-13 Unicode charmap codec|
2743 +---------+-----------+-----------+-----------------------------+
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002744
Mark Hammond2a0af792001-05-14 03:09:36 +00002745- Some operating systems now support the concept of a default Unicode
2746 encoding for file system operations. Notably, Windows supports 'mbcs'
2747 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002748 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +00002749 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002750
2751 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +00002752 functions that return filenames (such as os.listdir()) to return Python
2753 string objects pre-encoded using the default file system encoding for
2754 the platform. As this encoding is likely to be different from Python's
2755 default encoding, converting this name to a Unicode object before passing
2756 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +00002757 would attempt to use its default encoding (generally ASCII) rather than
2758 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002759
Tim Petersa814db52001-05-14 07:05:58 +00002760 In general, this change simply removes surprises when working with
2761 Unicode and the file system, making these operations work as you expect,
2762 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +00002763 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +00002764
Tim Peters61dff2b2001-05-08 15:43:37 +00002765- Float (and complex) literals in source code were evaluated to full
2766 precision only when running from a .py file; the same code loaded from a
2767 .pyc (or .pyo) file could suffer numeric differences starting at about the
2768 12th significant decimal digit. For example, on a machine with IEEE-754
2769 floating arithmetic,
2770
2771 x = 9007199254740992.0
2772 print long(x)
2773
2774 printed 9007199254740992 if run directly from .py, but 9007199254740000
2775 if from a compiled (.pyc or .pyo) file. This was due to marshal using
2776 str(float) instead of repr(float) when building code objects. marshal
2777 now uses repr(float) instead, which should reproduce floats to full
2778 machine precision (assuming the platform C float<->string I/O conversion
2779 functions are of good quality).
2780
2781 This may cause floating-point results to change in some cases, and
2782 usually for the better, but may also cause numerically unstable
2783 algorithms to break.
2784
Tim Peters2f228e72001-05-13 00:19:31 +00002785- The implementation of dicts suffers fewer collisions, which has speed
2786 benefits. However, the order in which dict entries appear in dict.keys(),
2787 dict.values() and dict.items() may differ from previous releases for a
2788 given dict. Nothing is defined about this order, so no program should
2789 rely on it. Nevertheless, it's easy to write test cases that rely on the
2790 order by accident, typically because of printing the str() or repr() of a
2791 dict to an "expected results" file. See Lib/test/test_support.py's new
2792 sortdict(dict) function for a simple way to display a dict in sorted
2793 order.
2794
Tim Peters7a3bfc32001-06-12 01:22:22 +00002795- Many other small changes to dicts were made, resulting in faster
2796 operation along the most common code paths.
2797
Guido van Rossum10315822001-05-01 20:54:30 +00002798- Dictionary objects now support the "in" operator: "x in dict" means
2799 the same as dict.has_key(x).
2800
Barry Warsaw51acc8d2001-06-26 20:12:50 +00002801- The update() method of dictionaries now accepts generic mapping
2802 objects. Specifically the argument object must support the .keys()
2803 and __getitem__() methods. This allows you to say, for example,
2804 {}.update(UserDict())
2805
Guido van Rossum10315822001-05-01 20:54:30 +00002806- Iterators were added; this is a generalized way of providing values
2807 to a for loop. See PEP 234. There's a new built-in function iter()
2808 to return an iterator. There's a new protocol to get the next value
2809 from an iterator using the next() method (in Python) or the
2810 tp_iternext slot (in C). There's a new protocol to get iterators
2811 using the __iter__() method (in Python) or the tp_iter slot (in C).
2812 Iterating (i.e. a for loop) over a dictionary generates its keys.
2813 Iterating over a file generates its lines.
2814
Tim Petersf553f892001-05-01 20:45:31 +00002815- The following functions were generalized to work nicely with iterator
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002816 arguments::
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002817
Tim Peterse63415e2001-05-08 04:38:29 +00002818 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +00002819 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
2820 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +00002821 join() method of strings
2822 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +00002823 'x in y' and 'x not in y' (PySequence_Contains() in C API)
2824 operator.countOf() (PySequence_Count() in C API)
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002825 right-hand side of assignment statements with multiple targets, such as ::
Tim Petersd6d010b2001-06-21 02:49:55 +00002826 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +00002827
Tim Petersd85e1022001-05-11 21:51:48 +00002828- Accessing module attributes is significantly faster (for example,
2829 random.random or os.path or yourPythonModule.yourAttribute).
2830
Tim Peterse63415e2001-05-08 04:38:29 +00002831- Comparing dictionary objects via == and != is faster, and now works even
2832 if the keys and values don't support comparisons other than ==.
2833
Tim Peters95bf9392001-05-10 08:32:44 +00002834- Comparing dictionaries in ways other than == and != is slower: there were
2835 insecurities in the dict comparison implementation that could cause Python
2836 to crash if the element comparison routines for the dict keys and/or
2837 values mutated the dicts. Making the code bulletproof slowed it down.
2838
Tim Peterseb28ef22001-06-02 05:27:19 +00002839- Collisions in dicts are resolved via a new approach, which can help
2840 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +00002841 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +00002842 faster now. Thanks to Christian Tismer for pointing out the cause and
2843 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +00002844
Tim Peters52e155e2001-06-16 05:42:57 +00002845- repr() is much faster for large containers (dict, list, tuple).
2846
2847
Tim Petersa814db52001-05-14 07:05:58 +00002848Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002849-------
Tim Petersa814db52001-05-14 07:05:58 +00002850
Fred Drake960fdf92001-07-20 18:38:26 +00002851- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002852 were added to the string module. These a locale-independent
Fred Drake960fdf92001-07-20 18:38:26 +00002853 constants, unlike letters, lowercase, and uppercase. These are now
2854 use in appropriate locations in the standard library.
2855
Martin v. Löwisf0473d52001-07-18 16:17:16 +00002856- The flags used in dlopen calls can now be configured using
2857 sys.setdlopenflags and queried using sys.getdlopenflags.
2858
Guido van Rossumc7e4aca2001-07-12 11:54:37 +00002859- Fredrik Lundh's xmlrpclib is now a standard library module. This
2860 provides full client-side XML-RPC support. In addition,
2861 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
2862 one asyncore-based). Thanks to Eric Raymond for the documentation.
2863
Guido van Rossum643d3912001-07-05 14:46:25 +00002864- The xrange() object is simplified: it no longer supports slicing,
2865 repetition, comparisons, efficient 'in' checking, the tolist()
2866 method, or the start, stop and step attributes. See PEP 260.
2867
Martin v. Löwisebf94db2001-06-06 06:25:40 +00002868- A new function fnmatch.filter to filter lists of file names was added.
2869
Barry Warsawffd674d2001-05-22 16:00:10 +00002870- calendar.py uses month and day names based on the current locale.
2871
Guido van Rossum2e0a6542001-05-15 02:14:44 +00002872- strop is now *really* obsolete (this was announced before with 1.6),
2873 and issues DeprecationWarning when used (except for the four items
2874 that are still imported into string.py).
2875
Tim Petersa814db52001-05-14 07:05:58 +00002876- Cookie.py now sorts key+value pairs by key in output strings.
2877
2878- pprint.isrecursive(object) didn't correctly identify recursive objects.
2879 Now it does.
2880
Tim Peters95b3f782001-05-14 18:39:41 +00002881- pprint functions now much faster for large containers (tuple, list, dict).
2882
Tim Peters7b9542a2001-06-10 23:40:19 +00002883- New 'q' and 'Q' format codes in the struct module, corresponding to C
2884 types "long long" and "unsigned long long" (on Windows, __int64). In
2885 native mode, these can be used only when the platform C compiler supports
2886 these types (when HAVE_LONG_LONG is #define'd by the Python config
2887 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +00002888 In standard mode, 'q' and 'Q' are supported on all platforms, and are
2889 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +00002890
Guido van Rossum83213cc2001-06-12 16:48:52 +00002891- The site module installs a new built-in function 'help' that invokes
2892 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
2893 it displays a message reminding the user to use 'help()' or
2894 'help(object)'.
2895
Tim Petersa814db52001-05-14 07:05:58 +00002896Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002897-----
Tim Petersa814db52001-05-14 07:05:58 +00002898
2899- New test_mutants.py runs dict comparisons where the key and value
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002900 comparison operators mutate the dicts randomly during comparison. This
Tim Petersa814db52001-05-14 07:05:58 +00002901 rapidly causes Python to crash under earlier releases (not for the faint
2902 of heart: it can also cause Win9x to freeze or reboot!).
2903
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002904- New test_pprint.py verifies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +00002905 pprint.isreadable() return sensible results. Also verifies that simple
2906 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +00002907
Tim Peters4324aa32001-05-28 22:30:08 +00002908C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002909-----
Tim Peters4324aa32001-05-28 22:30:08 +00002910
2911- Removed the unused last_is_sticky argument from the internal
2912 _PyTuple_Resize(). If this affects you, you were cheating.
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002913
2914----
2915
2916**(For information about older versions, consult the HISTORY file.)**