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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
Guido van Rossum4b499dd32003-02-13 22:07:59 +000015- Finally fixed the bug in compile() and exec where a string ending
16 with an indented code block but no newline would raise SyntaxError.
17 This would have been a four-line change in parsetok.c... Except
18 codeop.py depends on this behavior, so a compilation flag had to be
19 invented that causes the tokenizer to revert to the old behavior;
20 this required extra changes to 2 .h files, 2 .c files, and 2 .py
Guido van Rossum1442dc12003-02-13 22:19:20 +000021 files. (Fixes SF bug #501622.)
Guido van Rossum4b499dd32003-02-13 22:07:59 +000022
Guido van Rossum298e4212003-02-13 16:30:16 +000023- If a new-style class defines neither __new__ nor __init__, its
24 constructor would ignore all arguments. This is changed now: the
25 constructor refuses arguments in this case. This might break code
26 that worked under Python 2.2. The simplest fix is to add a no-op
27 __init__: "def __init__(self, *args, **kw): pass".
28
Guido van Rossum48035eb2003-02-12 17:05:26 +000029- Through a bytecode optimizer bug (and I bet you didn't even know
30 Python *had* a bytecode optimizer :-), "unsigned" hex/oct constants
31 with a leading minus sign would come out with the wrong sign.
32 ("Unsigned" hex/oct constants are those with a face value in the
33 range sys.maxint+1 through sys.maxint*2+1, inclusive; these have
34 always been interpreted as negative numbers through sign folding.)
35 E.g. 0xffffffff is -1, and -(0xffffffff) is 1, but -0xffffffff would
36 come out as -4294967295. This was the case in Python 2.2 through
37 2.2.2 and 2.3a1, and in Python 2.4 it will once again have that
38 value, but according to PEP 237 it really needs to be 1 now. This
39 will be backported to Python 2.2.3 a well. (SF #660455)
40
Guido van Rossum47710652003-02-12 20:48:22 +000041- int(s, base) sometimes sign-folds hex and oct constants; it only
42 does this when base is 0 and s.strip() starts with a '0'. When the
43 sign is actually folded, as in int("0xffffffff", 0) on a 32-bit
44 machine, which returns -1, a FutureWarning is now issued; in Python
45 2.4, this will return 4294967295L, as do int("+0xffffffff", 0) and
46 int("0xffffffff", 16) right now. (PEP 347)
47
Guido van Rossuma89d10e2003-02-12 03:58:38 +000048- super(X, x): x may now be a proxy for an X instance, i.e.
49 issubclass(x.__class__, X) but not issubclass(type(x), X).
50
Guido van Rossum03bc7d32003-02-12 03:32:58 +000051- isinstance(x, X): if X is a new-style class, this is now equivalent
52 to issubclass(type(x), X) or issubclass(x.__class__, X). Previously
53 only type(x) was tested. (For classic classes this was already the
54 case.)
55
Just van Rossum73ffb4a2003-02-10 09:57:08 +000056- compile(), eval() and the exec statement now fully support source code
57 passed as unicode strings.
58
Neal Norwitzde8b94c2003-02-10 02:12:43 +000059- int subclasses can be initialized with longs if the value fits in an int.
60 See SF bug #683467.
61
Tim Petersbf2674b2003-02-02 07:51:32 +000062- long(string, base) takes time linear in len(string) when base is a power
63 of 2 now. It used to take time quadratic in len(string).
64
Martin v. Löwis8afd7572003-01-25 22:46:11 +000065- filter returns now Unicode results for Unicode arguments.
66
Martin v. Löwisaf6a27a2003-01-03 19:16:14 +000067- raw_input can now return Unicode objects.
68
Skip Montanaro4abd5f02003-01-02 20:51:08 +000069- List objects' sort() method now accepts None as the comparison function.
70 Passing None is semantically identical to calling sort() with no
71 arguments.
72
Neal Norwitz1a997502003-01-13 20:13:12 +000073- Fixed crash when printing a subclass of str and __str__ returned self.
74 See SF bug #667147.
75
Neal Norwitzabcb0c02003-01-28 19:21:24 +000076- Fixed an invalid RuntimeWarning and an undetected error when trying
Tim Peters506be282003-01-31 22:27:17 +000077 to convert a long integer into a float which couldn't fit.
Neal Norwitzabcb0c02003-01-28 19:21:24 +000078 See SF bug #676155.
79
Guido van Rossum26507db2003-02-06 16:16:50 +000080- Function objects now have a __module__ attribute that is bound to
Jeremy Hylton0253d6e2003-02-06 16:00:15 +000081 the name of the module in which the function was defined. This
Guido van Rossum26507db2003-02-06 16:16:50 +000082 applies for C functions and methods as well as functions and methods
83 defined in Python. This attribute is used by pickle.whichmodule(),
84 which changes the behavior of whichmodule slightly. In Python 2.2
85 whichmodule() returns "__main__" for functions that are not defined
86 at the top-level of a module (examples: methods, nested functions).
87 Now whichmodule() will return the proper module name.
Jeremy Hylton0253d6e2003-02-06 16:00:15 +000088
Martin v. Löwis14e73b12003-01-01 09:51:12 +000089Extension modules
90-----------------
91
Guido van Rossumc4f4ca92003-02-12 21:46:11 +000092- The imp module now has ways to acquire and release the "import
93 lock": imp.acquire_lock() and imp.release_lock(). Note: this is a
94 reentrant lock, so releasing the lock only truly releases it when
95 this is the last release_lock() call. You can check with
96 imp.lock_held(). (SF bug #580952 and patch #683257.)
97
Neal Norwitz9caf9c02003-02-10 01:54:06 +000098- Fix some bugs in the parser module. SF bug #678518.
99
Guido van Rossum7d9ea502003-02-03 20:45:52 +0000100- Thanks to Scott David Daniels, a subtle bug in how the zlib
Walter Dörwald28d81962003-02-03 20:53:14 +0000101 extension implemented flush() was fixed. Scott also rewrote the
Guido van Rossum7d9ea502003-02-03 20:45:52 +0000102 zlib test suite using the unittest module. (SF bug #640230 and
103 patch #678531.)
104
Raymond Hettinger96ef8112003-02-01 00:10:11 +0000105- Added an itertools module containing high speed, memory efficient
106 looping constructs inspired by tools from Haskell and SML.
107
Guido van Rossum99d4abf2003-01-27 22:22:50 +0000108- The SSL module now handles sockets with a timeout set correctly (SF
109 patch #675750, fixing SF bug #675552).
110
Martin v. Löwis9789aef2003-01-26 11:30:36 +0000111- A new module _iconv_codec has been added, to expose the iconv(3)
112 library.
113
Barry Warsawf8ba39c2003-01-07 20:55:26 +0000114- os/posixmodule has grown the sysexits.h constants (EX_OK and friends).
115
Guido van Rossum6d0d3652003-01-07 20:34:19 +0000116- Fixed broken threadstate swap in readline that could cause fatal
117 errors when a readline hook was being invoked while a background
118 thread was active. (SF bugs #660476 and #513033.)
119
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000120- fcntl now exposes the strops.h I_* constants.
121
Tim Peters00640262003-01-24 15:31:31 +0000122- Fix a crash on Solaris that occurred when calling close() on
123 an mmap'ed file which was already closed. (SF patch #665913)
124
Tim Peters01231392003-01-02 19:10:19 +0000125- datetime changes:
126
Tim Peters0bf60bd2003-01-08 20:40:01 +0000127 The datetime and datetimetz classes have been collapsed into a single
128 datetime class, and likewise the time and timetz classes into a single
129 time class. Previously, a datetimetz object with tzinfo=None acted
130 exactly like a datetime object, and similarly for timetz. This wasn't
131 enough of a difference to justify distinct classes, and life is simpler
132 now.
133
Tim Peters01231392003-01-02 19:10:19 +0000134 today() and now() now round system timestamps to the closest
Tim Petersadf64202003-01-04 06:03:15 +0000135 microsecond <http://www.python.org/sf/661086>. This repairs an
136 irritation most likely seen on Windows systems.
Tim Peters01231392003-01-02 19:10:19 +0000137
Tim Petersf196a0a2003-01-22 04:45:50 +0000138 In dt.astimezone(tz), if tz.utcoffset(dt) returns a duration,
Tim Peters397301e2003-01-02 21:28:08 +0000139 ValueError is raised if tz.dst(dt) returns None (2.3a1 treated it
Tim Petersadf64202003-01-04 06:03:15 +0000140 as 0 instead, but a tzinfo subclass wishing to participate in
141 time zone conversion has to take a stand on whether it supports
142 DST; if you don't care about DST, then code dst() to return 0 minutes,
143 meaning that DST is never in effect).
Tim Peters397301e2003-01-02 21:28:08 +0000144
Tim Peters77023042003-01-03 22:35:24 +0000145 The tzinfo methods utcoffset() and dst() must return a timedelta object
146 (or None) now. In 2.3a1 they could also return an int or long, but that
147 was an unhelpfully redundant leftover from an earlier version wherein
Tim Peters397301e2003-01-02 21:28:08 +0000148 they couldn't return a timedelta. TOOWTDI.
149
Tim Peters77023042003-01-03 22:35:24 +0000150 The example tzinfo class for local time had a bug. It was replaced
151 by a later example coded by Guido.
152
Tim Petersf196a0a2003-01-22 04:45:50 +0000153 datetime.astimezone(tz) no longer raises an exception when the
Tim Petersadf64202003-01-04 06:03:15 +0000154 input datetime has no UTC equivalent in tz. For typical "hybrid" time
155 zones (a single tzinfo subclass modeling both standard and daylight
156 time), this case can arise one hour per year, at the hour daylight time
Tim Petersf196a0a2003-01-22 04:45:50 +0000157 ends. See new docs for details. In short, the new behavior mimics
158 the local wall clock's behavior of repeating an hour in local time.
159
160 dt.astimezone() can no longer be used to convert between naive and aware
161 datetime objects. If you merely want to attach, or remove, a tzinfo
162 object, without any conversion of date and time members, use
163 dt.replace(tzinfo=whatever) instead, where "whatever" is None or a
164 tzinfo subclass instance.
165
166 A new method tzinfo.fromutc(dt) can be overridden in tzinfo subclasses
167 to give complete control over how a UTC time is to be converted to
168 a local time. The default astimezone() implementation calls fromutc()
169 as its last step, so a tzinfo subclass can affect that too by overriding
170 fromutc(). It's expected that the default fromutc() implementation will
171 be suitable as-is for "almost all" time zone subclasses, but the
172 creativity of political time zone fiddling appears unbounded -- fromutc()
173 allows the highly motivated to emulate any scheme expressible in Python.
Tim Petersadf64202003-01-04 06:03:15 +0000174
Tim Peters10cadce2003-01-23 19:58:02 +0000175 datetime.now(): The optional tzinfo argument was undocumented (that's
176 repaired), and its name was changed to tz ("tzinfo" is overloaded enough
177 already). With a tz argument, now(tz) used to return the local date
178 and time, and attach tz to it, without any conversion of date and time
179 members. This was less than useful. Now now(tz) returns the current
180 date and time as local time in tz's time zone, akin to
181 tz.fromutc(datetime.utcnow().replace(tzinfo=utc))
182 where "utc" is an instance of a tzinfo subclass modeling UTC. Without
183 a tz argument, now() continues to return the current local date and time,
184 as a naive datetime object.
185
Tim Peters2a44a8d2003-01-23 20:53:10 +0000186 datetime.fromtimestamp(): Like datetime.now() above, this had less than
187 useful behavior when the optional tinzo argument was specified. See
188 also SF bug report <http://www.python.org/sf/660872>.
189
Tim Peters8d81a012003-01-24 22:36:34 +0000190 date and datetime comparison: In order to prevent comparison from
191 falling back to the default compare-object-addresses strategy, these
192 raised TypeError whenever they didn't understand the other object type.
193 They still do, except when the other object has a "timetuple" attribute,
194 in which case they return NotImplemented now. This gives other
195 datetime objects (e.g., mxDateTime) a chance to intercept the
196 comparison.
197
Tim Peters07534a62003-02-07 22:50:28 +0000198 date, time, datetime and timedelta comparison: When the exception
199 for mixed-type comparisons in the last paragraph doesn't apply, if
200 the comparison is == then False is returned, and if the comparison is
201 != then True is returned. Because dict lookup and the "in" operator
202 only invoke __eq__, this allows, for example,
203
204 if some_datetime in some_sequence:
205 and
206 some_dict[some_timedelta] = whatever
207
208 to work as expected, without raising TypeError just because the
209 sequence is heterogeneous, or the dict has mixed-type keys. [This
210 seems like a good idea to implement for all mixed-type comparisons
211 that don't want to allow falling back to address comparison.]
212
Tim Peters75a6e3b2003-01-04 18:17:36 +0000213 The constructors building a datetime from a timestamp could raise
214 ValueError if the platform C localtime()/gmtime() inserted "leap
215 seconds". Leap seconds are ignored now. On such platforms, it's
216 possible to have timestamps that differ by a second, yet where
217 datetimes constructed from them are equal.
218
Tim Peters506be282003-01-31 22:27:17 +0000219 The pickle format of date, time and datetime objects has changed
220 completely. The undocumented pickler and unpickler functions no
Tim Petersb57f8f02003-02-01 02:54:15 +0000221 longer exist. The undocumented __setstate__() and __getstate__()
222 methods no longer exist either.
Tim Peters506be282003-01-31 22:27:17 +0000223
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000224Library
225-------
226
Andrew MacIntyre251b8162003-02-17 09:20:23 +0000227- the platform dependent path related variables sep, altsep, extsep,
228 pathsep, curdir, pardir and defpath are now defined in the platform
Michael W. Hudson9e5d87f2003-02-17 12:26:23 +0000229 dependent path modules (e.g. ntpath.py) rather than os.py, so these
230 variables are now available via os.path. They continue to be
231 available from the os module.
232 (see <http://www.python.org/sf/680789>).
Andrew MacIntyre251b8162003-02-17 09:20:23 +0000233
Tim Peters6ee04802003-02-05 18:29:34 +0000234- array.array was added to the types repr.py knows about (see
235 <http://www.python.org/sf/680789>).
236
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000237- The new pickletools.py contains lots of documentation about pickle
238 internals, and supplies some helpers for working with pickles, such as
239 a symbolic pickle disassembler.
240
Skip Montanaro9a7c96a2003-01-22 18:17:25 +0000241- Xmlrpclib.py now supports the builtin boolean type.
242
Martin v. Löwis0c6774d2003-01-15 11:51:06 +0000243- py_compile has a new 'doraise' flag and a new PyCompileError
244 exception.
245
Martin v. Löwisd69663d2003-01-15 11:37:23 +0000246- SimpleXMLRPCServer now supports CGI through the CGIXMLRPCRequestHandler
247 class.
248
Guido van Rossum50e92232003-01-14 16:45:04 +0000249- The sets module now raises TypeError in __cmp__, to clarify that
250 sets are not intended to be three-way-compared; the comparison
251 operators are overloaded as subset/superset tests.
252
Guido van Rossumcd0c0472003-01-07 23:03:05 +0000253- Bastion.py and rexec.py are disabled. These modules are not safe in
254 Python 2.2. or 2.3.
255
Neal Norwitzbb0246a2003-01-03 18:12:28 +0000256- realpath is now exported when doing from poxixpath import *.
257 It is also exported for ntpath, macpath, and os2emxpath.
258 See SF bug #659228.
259
Neal Norwitzb9ef4ae2003-01-05 23:19:43 +0000260- New module tarfile from Lars Gustäbel provides a comprehensive interface
261 to tar archive files with transparent gzip and bzip2 compression.
262 See SF patch #651082.
263
Neal Norwitz4f442372003-01-06 06:51:36 +0000264- urlparse can now parse imap:// URLs. See SF feature request #618024.
David Goodgerf349e262003-01-03 03:30:21 +0000265
Neal Norwitze931ed52003-01-10 23:24:32 +0000266- Tkinter.Canvas.scan_dragto() provides an optional parameter to support
267 the gain value which is passed to Tk. SF bug# 602259.
268
Neal Norwitze4c40da2003-01-26 02:45:47 +0000269- Fix logging.handlers.SysLogHandler protocol when using UNIX domain sockets.
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000270 See SF patch #642974.
Neal Norwitze4c40da2003-01-26 02:45:47 +0000271
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000272Tools/Demos
273-----------
274
Skip Montanaro13b29102003-02-03 15:17:25 +0000275- Two new scripts (db2pickle.py and pickle2db.py) were added to the
276 Tools/scripts directory to facilitate conversion from the old bsddb module
277 to the new one. While the user-visible API of the new module is
278 compatible with the old one, it's likely that the version of the
279 underlying database library has changed. To convert from the old library,
280 run the db2pickle.py script using the old version of Python to convert it
281 to a pickle file. After upgrading Python, run the pickle2db.py script
282 using the new version of Python to reconstitute your database. For
283 example:
284
Skip Montanaro621f0552003-02-03 15:48:10 +0000285 % python2.2 db2pickle.py -h some.db > some.pickle
286 % python2.3 pickle2db.py -h some.db.new < some.pickle
Skip Montanaro13b29102003-02-03 15:17:25 +0000287
288 Run the scripts without any args to get a usage message.
289
David Goodgerf349e262003-01-03 03:30:21 +0000290
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000291Build
292-----
293
Guido van Rossum4507ec72003-02-14 19:29:22 +0000294- The audio driver tests (test_ossaudiodev.py and
295 test_linuxaudiodev.py) are no longer run by default. This is
296 because they don't always work, depending on your hardware and
297 software. To run these tests, you must use an invocation like
298 ./python Lib/test/regrtest.py -u audio test_ossaudiodev
299
Skip Montanarodecc6a42003-01-01 20:07:49 +0000300- On systems which build using the configure script, compiler flags which
301 used to be lumped together using the OPT flag have been split into two
302 groups, OPT and BASECFLAGS. OPT is meant to carry just optimization- and
303 debug-related flags like "-g" and "-O3". BASECFLAGS is meant to carry
304 compiler flags that are required to get a clean compile. On some
305 platforms (many Linux flavors in particular) BASECFLAGS will be empty by
306 default. On others, such as Mac OS X and SCO, it will contain required
307 flags. This change allows people building Python to override OPT without
308 fear of clobbering compiler flags which are required to get a clean build.
309
310- On Darwin/Mac OS X platforms, /sw/lib and /sw/include are added to the
311 relevant search lists in setup.py. This allows users building Python to
312 take advantage of the many packages available from the fink project
313 <http://fink.sf.net/>.
314
315- A new Makefile target, scriptsinstall, installs a number of useful scripts
316 from the Tools/scripts directory.
317
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000318C API
319-----
320
Guido van Rossumeea47182003-02-11 20:39:59 +0000321- A C type that inherits from a base type that defines tp_as_buffer
322 will now inherit the tp_as_buffer pointer if it doesn't define one.
323 (SF #681367)
324
Neil Schemenauer5042da62003-02-04 20:59:40 +0000325- The PyArg_Parse functions now issue a DeprecationWarning if a float
326 argument is provided when an integer is specified (this affects the 'b',
327 'B', 'h', 'H', 'i', and 'l' codes). Future versions of Python will
328 raise a TypeError.
Neil Schemenauercd63e612003-01-24 22:15:53 +0000329
David Goodgerf349e262003-01-03 03:30:21 +0000330
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000331New platforms
332-------------
333
David Goodgerf349e262003-01-03 03:30:21 +0000334TBD
335
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000336Tests
337-----
338
David Goodgerf349e262003-01-03 03:30:21 +0000339TBD
340
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000341Windows
342-------
343
Thomas Hellerdda583d2003-01-31 20:45:41 +0000344- distutils' msvccompiler class now passes the preprocessor options to
345 the resource compiler. See SF patch #669198.
346
Tim Peters00640262003-01-24 15:31:31 +0000347- The bsddb module now ships with Sleepycat's 4.1.25.NC, the latest
348 release without strong cryptography.
349
Thomas Heller6c64fa72003-01-08 15:14:55 +0000350- sys.path[0], if it contains a directory name, is now always an
351 absolute pathname.
352
Tim Petersbbc5d162003-01-02 16:02:27 +0000353- The new logging package is now installed by the Windows installer. It
354 wasn't in 2.3a1 due to oversight.
355
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000356Mac
357---
358
Jack Jansen1a1b6e42003-01-27 15:21:39 +0000359- There are new dialogs EasyDialogs.AskFileForOpen, AskFileForSave
360 and AskFolder. The old macfs.StandardGetFile and friends are deprecated.
Tim Peters07534a62003-02-07 22:50:28 +0000361
Jack Jansenc9296362003-02-06 23:10:45 +0000362- Most of the standard library now uses pathnames or FSRefs in preference
363 of FSSpecs, and use the underlying Carbon.File and Carbon.Folder modules
364 in stead of macfs. macfs will probably be deprecated in the future.
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000365
Jack Jansen1a1b6e42003-01-27 15:21:39 +0000366- Type Carbon.File.FSCatalogInfo and supporting methods have been implemented.
367 This also makes macfs.FSSpec.SetDates() work again.
Jack Jansen9f70aab2003-02-16 23:00:53 +0000368
369- There is a new module pimp, the package install manager for Python, and
370 accompanying applet PackageManager. These allow you to easily download
371 and install pretested extension packages either in source or binary
372 form. Only in MacPython-OSX.
373
374- Applets are now built with bundlebuilder in MacPython-OSX, which should make
375 them more robust and also provides a path towards BuildApplication.
David Goodgerf349e262003-01-03 03:30:21 +0000376
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000377
Tim Petersaf8446f2001-12-21 21:36:50 +0000378What's New in Python 2.3 alpha 1?
Tim Petersaf8446f2001-12-21 21:36:50 +0000379=================================
380
Guido van Rossumae548862002-12-31 15:47:36 +0000381*Release date: 31-Dec-2002*
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000382
Tim Petersaf8446f2001-12-21 21:36:50 +0000383Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000384--------------------------------------------
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000385
Michael W. Hudson96bc3b42002-11-26 14:48:23 +0000386- One can now assign to __bases__ and __name__ of new-style classes.
387
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000388- dict() now accepts keyword arguments so that dict(one=1, two=2)
389 is the equivalent of {"one": 1, "two": 2}. Accordingly,
Just van Rossuma797d812002-11-23 09:45:04 +0000390 the existing (but undocumented) 'items' keyword argument has
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000391 been eliminated. This means that dict(items=someMapping) now has
Just van Rossuma797d812002-11-23 09:45:04 +0000392 a different meaning than before.
393
Walter Dörwaldf1715402002-11-19 20:49:15 +0000394- int() now returns a long object if the argument is outside the
David Goodgerf349e262003-01-03 03:30:21 +0000395 integer range, so int("4" * 1000), int(1e200) and int(1L<<1000) will
Walter Dörwaldf1715402002-11-19 20:49:15 +0000396 all return long objects instead of raising an OverflowError.
Tim Petersaf8446f2001-12-21 21:36:50 +0000397
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000398- Assignment to __class__ is disallowed if either the old or the new
Guido van Rossume3438782002-08-12 03:42:03 +0000399 class is a statically allocated type object (such as defined by an
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000400 extension module). This prevents anomalies like 2.__class__ = bool.
Guido van Rossume3438782002-08-12 03:42:03 +0000401
402- New-style object creation and deallocation have been sped up
403 significantly; they are now faster than classic instance creation
404 and deallocation.
405
406- The __slots__ variable can now mention "private" names, and the
407 right thing will happen (e.g. __slots__ = ["__foo"]).
408
409- The built-ins slice() and buffer() are now callable types. The
410 types classobj (formerly class), code, function, instance, and
411 instancemethod (formerly instance-method), which have no built-in
412 names but are accessible through the types module, are now also
413 callable. The type dict-proxy is renamed to dictproxy.
414
415- Cycles going through the __class__ link of a new-style instance are
416 now detected by the garbage collector.
417
418- Classes using __slots__ are now properly garbage collected.
419 [SF bug 519621]
420
421- Tightened the __slots__ rules: a slot name must be a valid Python
422 identifier.
423
424- The constructor for the module type now requires a name argument and
425 takes an optional docstring argument. Previously, this constructor
426 ignored its arguments. As a consequence, deriving a class from a
427 module (not from the module type) is now illegal; previously this
428 created an unnamed module, just like invoking the module type did.
429 [SF bug 563060]
430
431- A new type object, 'basestring', is added. This is a common base type
432 for 'str' and 'unicode', and can be used instead of
433 types.StringTypes, e.g. to test whether something is "a string":
434 isinstance(x, basestring) is True for Unicode and 8-bit strings. This
435 is an abstract base class and cannot be instantiated directly.
436
437- Changed new-style class instantiation so that when C's __new__
438 method returns something that's not a C instance, its __init__ is
439 not called. [SF bug #537450]
440
441- Fixed super() to work correctly with class methods. [SF bug #535444]
442
443- If you try to pickle an instance of a class that has __slots__ but
444 doesn't define or override __getstate__, a TypeError is now raised.
445 This is done by adding a bozo __getstate__ to the class that always
446 raises TypeError. (Before, this would appear to be pickled, but the
447 state of the slots would be lost.)
448
Tim Petersaf8446f2001-12-21 21:36:50 +0000449Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000450-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000451
Guido van Rossuma3b89532002-12-30 22:59:32 +0000452- Import from zipfiles is now supported. The name of a zipfile placed
Just van Rossum01875eb2002-12-31 10:22:38 +0000453 on sys.path causes the import statement to look for importable Python
454 modules (with .py, pyc and .pyo extensions) and packages inside the
455 zipfile. The zipfile import follows the specification (though not
456 the sample implementation) of PEP 273. The semantics of __path__ are
Guido van Rossuma3b89532002-12-30 22:59:32 +0000457 compatible with those that have been implemented in Jython since
458 Jython 2.1.
459
Just van Rossum01875eb2002-12-31 10:22:38 +0000460- PEP 302 has been accepted. Although it was inititally developed to
Tim Petersbbc5d162003-01-02 16:02:27 +0000461 support zipimport, it offers a new, general import hook mechanism.
Just van Rossum01875eb2002-12-31 10:22:38 +0000462 Several new variables have been added to the sys module:
463 sys.meta_path, sys.path_hooks, and sys.path_importer_cache; these
464 make extending the import statement much more convenient than
465 overriding the __import__ built-in function. For a description of
466 these, see PEP 302.
467
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000468- A frame object's f_lineno attribute can now be written to from a
469 trace function to change which line will execute next. A command to
470 exploit this from pdb has been added. [SF patch #643835]
471
Marc-André Lemburg20b91352002-12-12 18:01:43 +0000472- The _codecs support module for codecs.py was turned into a builtin
473 module to assure that at least the builtin codecs are available
474 to the Python parser for source code decoding according to PEP 263.
475
Walter Dörwaldd9a6ad32002-12-12 16:41:44 +0000476- issubclass now supports a tuple as the second argument, just like
477 isinstance does. ``issubclass(X, (A, B))`` is equivalent to
478 ``issubclass(X, A) or issubclass(X, B)``.
479
Tim Petersb9099c32002-11-12 22:08:10 +0000480- Thanks to Armin Rigo, the last known way to provoke a system crash
481 by cleverly arranging for a comparison function to mutate a list
482 during a list.sort() operation has been fixed. The effect of
483 attempting to mutate a list, or even to inspect its contents or
484 length, while a sort is in progress, is not defined by the language.
485 The C implementation of Python 2.3 attempts to detect mutations,
486 and raise ValueError if one occurs, but there's no guarantee that
487 all mutations will be caught, or that any will be caught across
488 releases or implementations.
489
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000490- Unicode file name processing for Windows (PEP 277) is implemented.
Mark Hammond8696ebc2002-10-08 02:44:31 +0000491 All platforms now have an os.path.supports_unicode_filenames attribute,
492 which is set to True on Windows NT/2000/XP, and False elsewhere.
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000493
Walter Dörwald3aeb6322002-09-02 13:14:32 +0000494- Codec error handling callbacks (PEP 293) are implemented.
495 Error handling in unicode.encode or str.decode can now be customized.
496
Guido van Rossum45ec02a2002-08-19 21:43:18 +0000497- A subtle change to the semantics of the built-in function intern():
498 interned strings are no longer immortal. You must keep a reference
499 to the return value intern() around to get the benefit.
500
Guido van Rossumf808b892002-08-16 03:38:10 +0000501- Use of 'None' as a variable, argument or attribute name now
502 issues a SyntaxWarning. In the future, None may become a keyword.
503
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000504- SET_LINENO is gone. co_lnotab is now consulted to determine when to
505 call the trace function. C code that accessed f_lineno should call
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000506 PyCode_Addr2Line instead (f_lineno is still there, but only kept up
507 to date when there is a trace function set).
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000508
Guido van Rossum9be89462002-08-14 16:11:30 +0000509- There's a new warning category, FutureWarning. This is used to warn
510 about a number of situations where the value or sign of an integer
511 result will change in Python 2.4 as a result of PEP 237 (integer
512 unification). The warnings implement stage B0 mentioned in that
513 PEP. The warnings are about the following situations:
514
515 - Octal and hex literals without 'L' prefix in the inclusive range
516 [0x80000000..0xffffffff]; these are currently negative ints, but
517 in Python 2.4 they will be positive longs with the same bit
518 pattern.
519
520 - Left shifts on integer values that cause the outcome to lose
521 bits or have a different sign than the left operand. To be
522 precise: x<<n where this currently doesn't yield the same value
523 as long(x)<<n; in Python 2.4, the outcome will be long(x)<<n.
524
525 - Conversions from ints to string that show negative values as
526 unsigned ints in the inclusive range [0x80000000..0xffffffff];
527 this affects the functions hex() and oct(), and the string
528 formatting codes %u, %o, %x, and %X. In Python 2.4, these will
529 show signed values (e.g. hex(-1) currently returns "0xffffffff";
530 in Python 2.4 it will return "-0x1").
531
Guido van Rossum9a2eda52002-12-31 02:12:42 +0000532- The bits manipulated under the cover by sys.setcheckinterval() have
533 been changed. Both the check interval and the ticker used to be
534 per-thread values. They are now just a pair of global variables.
535 In addition, the default check interval was boosted from 10 to 100
536 bytecode instructions. This may have some effect on systems that
537 relied on the old default value. In particular, in multi-threaded
538 applications which try to be highly responsive, response time will
539 increase by some (perhaps imperceptible) amount.
Skip Montanaro979c74b2002-09-03 21:25:14 +0000540
Tim Petersd64c1de2002-08-12 17:36:03 +0000541- When multiplying very large integers, a version of the so-called
542 Karatsuba algorithm is now used. This is most effective if the
543 inputs have roughly the same size. If they both have about N digits,
544 Karatsuba multiplication has O(N**1.58) runtime (the exponent is
545 log_base_2(3)) instead of the previous O(N**2). Measured results may
Tim Peters012c0a32002-08-16 03:40:07 +0000546 be better or worse than that, depending on platform quirks. Besides
547 the O() improvement in raw instruction count, the Karatsuba algorithm
548 appears to have much better cache behavior on extremely large integers
549 (starting in the ballpark of a million bits). Note that this is a
550 simple implementation, and there's no intent here to compete with,
551 e.g., GMP. It gives a very nice speedup when it applies, but a package
552 devoted to fast large-integer arithmetic should run circles around it.
Tim Peters5af4e6c2002-08-12 02:31:19 +0000553
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000554- u'%c' will now raise a ValueError in case the argument is an
555 integer outside the valid range of Unicode code point ordinals.
556
Guido van Rossumdeb09362002-08-09 17:16:30 +0000557- The tempfile module has been overhauled for enhanced security. The
558 mktemp() function is now deprecated; new, safe replacements are
559 mkstemp() (for files) and mkdtemp() (for directories), and the
560 higher-level functions NamedTemporaryFile() and TemporaryFile().
561 Use of some global variables in this module is also deprecated; the
562 new functions have keyword arguments to provide the same
563 functionality. All Lib, Tools and Demo modules that used the unsafe
564 interfaces have been updated to use the safe replacements. Thanks
565 to Zack Weinberg!
566
Guido van Rossumd81a9832002-08-09 15:57:34 +0000567- When x is an object whose class implements __mul__ and __rmul__,
568 1.0*x would correctly invoke __rmul__, but 1*x would erroneously
569 invoke __mul__. This was due to the sequence-repeat code in the int
570 type. This has been fixed now.
571
Barry Warsawd79f6832002-08-06 17:01:51 +0000572- Previously, "str1 in str2" required str1 to be a string of length 1.
573 This restriction has been relaxed to allow str1 to be a string of
574 any length. Thus "'el' in 'hello world'" returns True now.
575
Guido van Rossumb57089c2002-08-06 16:20:26 +0000576- File objects are now their own iterators. For a file f, iter(f) now
577 returns f (unless f is closed), and f.next() is similar to
578 f.readline() when EOF is not reached; however, f.next() uses a
579 readahead buffer that messes up the file position, so mixing
580 f.next() and f.readline() (or other methods) doesn't work right.
581 Calling f.seek() drops the readahead buffer, but other operations
582 don't. It so happens that this gives a nice additional speed boost
583 to "for line in file:"; the xreadlines method and corresponding
Guido van Rossumbffb2ef2002-08-09 17:17:07 +0000584 module are now obsolete. Thanks to Oren Tirosh!
Guido van Rossumb57089c2002-08-06 16:20:26 +0000585
Guido van Rossumde392d32002-08-05 14:17:20 +0000586- Encoding declarations (PEP 263, phase 1) have been implemented. A
587 comment of the form "# -*- coding: <encodingname> -*-" in the first
588 or second line of a Python source file indicates the encoding.
Martin v. Löwis00f1e3f2002-08-04 17:29:52 +0000589
Tim Petersf47630f2002-08-01 02:34:51 +0000590- list.sort() has a new implementation. While cross-platform results
591 may vary, and in data-dependent ways, this is much faster on many
592 kinds of partially ordered lists than the previous implementation,
593 and reported to be just as fast on randomly ordered lists on
594 several major platforms. This sort is also stable (if A==B and A
595 precedes B in the list at the start, A precedes B after the sort too),
596 although the language definition does not guarantee stability. A
597 potential drawback is that list.sort() may require temp space of
Skip Montanaroa2a07bc2002-09-30 15:23:01 +0000598 len(list)*2 bytes (``*4`` on a 64-bit machine). It's therefore possible
Tim Petersf47630f2002-08-01 02:34:51 +0000599 for list.sort() to raise MemoryError now, even if a comparison function
600 does not. See <http://www.python.org/sf/587076> for full details.
601
Guido van Rossum2d5389c2002-07-23 03:44:35 +0000602- All standard iterators now ensure that, once StopIteration has been
603 raised, all future calls to next() on the same iterator will also
604 raise StopIteration. There used to be various counterexamples to
605 this behavior, which could caused confusion or subtle program
606 breakage, without any benefits. (Note that this is still an
607 iterator's responsibility; the iterator framework does not enforce
608 this.)
609
Mark Hammondc0e35152002-07-16 01:32:30 +0000610- Ctrl+C handling on Windows has been made more consistent with
611 other platforms. KeyboardInterrupt can now reliably be caught,
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000612 and Ctrl+C at an interactive prompt no longer terminates the
Mark Hammondc0e35152002-07-16 01:32:30 +0000613 process under NT/2k/XP (it never did under Win9x). Ctrl+C will
Tim Peters5af4e6c2002-08-12 02:31:19 +0000614 interrupt time.sleep() in the main thread, and any child processes
615 created via the popen family (on win2k; we can't make win9x work
Mark Hammond8f3afc72002-08-10 06:26:31 +0000616 reliably) are also interrupted (as generally happens on for Linux/Unix.)
617 [SF bugs 231273, 439992 and 581232]
Mark Hammondc0e35152002-07-16 01:32:30 +0000618
Mark Hammond8696ebc2002-10-08 02:44:31 +0000619- sys.getwindowsversion() has been added on Windows. This
620 returns a tuple with information about the version of Windows
621 currently running.
622
Raymond Hettinger5a04aec2002-06-25 00:25:30 +0000623- Slices and repetitions of buffer objects now consistently return
624 a string. Formerly, strings would be returned most of the time,
625 but a buffer object would be returned when the repetition count
626 was one or when the slice range was all inclusive.
627
Walter Dörwald3430d702002-06-17 10:43:59 +0000628- Unicode objects in sys.path are no longer ignored but treated
629 as directory names.
630
Neal Norwitz1f68fc72002-06-14 00:50:42 +0000631- Fixed string.startswith and string.endswith builtin methods
632 so they accept negative indices. [SF bug 493951]
633
Guido van Rossumc5fe5eb2002-06-12 03:45:21 +0000634- Fixed a bug with a continue inside a try block and a yield in the
635 finally clause. [SF bug 567538]
636
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000637- Most builtin sequences now support "extended slices", i.e. slices
Guido van Rossum2e82e712002-06-13 11:41:07 +0000638 with a third "stride" parameter. For example, "hello world"[::-1]
639 gives "dlrow olleh".
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000640
Neal Norwitzd68f5172002-05-29 15:54:55 +0000641- A new warning PendingDeprecationWarning was added to provide
642 direction on features which are in the process of being deprecated.
643 The warning will not be printed by default. To see the pending
644 deprecations, use -Walways::PendingDeprecationWarning::
645 as a command line option or warnings.filterwarnings() in code.
646
Fred Draked0ba6362002-05-02 21:28:26 +0000647- Deprecated features of xrange objects have been removed as
648 promised. The start, stop, and step attributes and the tolist()
649 method no longer exist. xrange repetition and slicing have been
650 removed.
651
Guido van Rossum7dab2422002-04-26 19:40:56 +0000652- New builtin function enumerate(x), from PEP 279. Example:
653 enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
654 The argument can be an arbitrary iterable object.
655
Neil Schemenauer89e3ee02002-04-26 01:58:53 +0000656- The assert statement no longer tests __debug__ at runtime. This means
657 that assert statements cannot be disabled by assigning a false value
658 to __debug__.
659
Walter Dörwald068325e2002-04-15 13:36:47 +0000660- A method zfill() was added to str and unicode, that fills a numeric
661 string to the left with zeros. For example,
662 "+123".zfill(6) -> "+00123".
663
Guido van Rossum862fe3c2002-04-15 12:36:47 +0000664- Complex numbers supported divmod() and the // and % operators, but
665 these make no sense. Since this was documented, they're being
666 deprecated now.
667
Guido van Rossum26dd8302002-04-26 20:11:29 +0000668- String and unicode methods lstrip(), rstrip() and strip() now take
669 an optional argument that specifies the characters to strip. For
670 example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
Guido van Rossum49042042002-04-13 00:59:05 +0000671
Guido van Rossumc0d3f4e2002-11-27 13:10:40 +0000672- There's a new dictionary constructor (a class method of the dict
673 class), dict.fromkeys(iterable, value=None). It constructs a
674 dictionary with keys taken from the iterable and all values set to a
675 single value. It can be used for building sets and for removing
676 duplicates from sequences.
Raymond Hettingere33d3df2002-11-27 07:29:33 +0000677
Guido van Rossumc69343b2002-04-12 19:22:48 +0000678- Added a new dict method pop(key). This removes and returns the
679 value corresponding to key. [SF patch #539949]
680
Guido van Rossum47834462002-04-04 15:21:33 +0000681- A new built-in type, bool, has been added, as well as built-in
682 names for its two values, True and False. Comparisons and sundry
683 other operations that return a truth value have been changed to
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000684 return a bool instead. Read PEP 285 for an explanation of why this
Guido van Rossum47834462002-04-04 15:21:33 +0000685 is backward compatible.
686
Guido van Rossum95b62a62002-03-29 01:07:24 +0000687- Fixed two bugs reported as SF #535905: under certain conditions,
688 deallocating a deeply nested structure could cause a segfault in the
689 garbage collector, due to interaction with the "trashcan" code;
690 access to the current frame during destruction of a local variable
691 could access a pointer to freed memory.
692
Guido van Rossumfe0ca4a2002-06-18 21:20:13 +0000693- The optional object allocator ("pymalloc") has been enabled by
694 default. The recommended practice for memory allocation and
695 deallocation has been streamlined. A header file is included,
696 Misc/pymemcompat.h, which can be bundled with 3rd party extensions
697 and lets them use the same API with Python versions from 1.5.2
698 onwards.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000699
Martin v. Löwiscfeb3b62002-03-03 21:30:27 +0000700- PyErr_Display will provide file and line information for all exceptions
701 that have an attribute print_file_and_line, not just SyntaxErrors.
702
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000703- The UTF-8 codec will now encode and decode Unicode surrogates
704 correctly and without raising exceptions for unpaired ones.
705
Guido van Rossumadd88062002-08-15 14:01:14 +0000706- Universal newlines (PEP 278) is implemented. Briefly, using 'U'
707 instead of 'r' when opening a text file for reading changes the line
708 ending convention so that any of '\r', '\r\n', and '\n' is
709 recognized (even mixed in one file); all three are converted to
710 '\n', the standard Python line end character.
711
Neal Norwitz649b7592002-01-01 19:07:13 +0000712- file.xreadlines() now raises a ValueError if the file is closed:
713 Previously, an xreadlines object was returned which would raise
714 a ValueError when the xreadlines.next() method was called.
715
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000716- sys.exit() inadvertently allowed more than one argument.
Neal Norwitz0c766a02002-03-27 13:03:09 +0000717 An exception will now be raised if more than one argument is used.
718
Gustavo Niemeyer17c5a332002-12-16 14:09:22 +0000719- Changed evaluation order of dictionary literals to conform to the
720 general left to right evaluation order rule. Now {f1(): f2()} will
721 evaluate f1 first.
Gustavo Niemeyer78429a62002-12-16 13:54:02 +0000722
Gustavo Niemeyer786ddb22002-12-16 18:12:53 +0000723- Fixed bug #521782: when a file was in non-blocking mode, file.read()
724 could silently lose data or wrongly throw an unknown error.
725
Neil Schemenauerb983aa02002-12-30 20:22:23 +0000726- The sq_repeat, sq_inplace_repeat, sq_concat and sq_inplace_concat
727 slots are now always tried after trying the corresponding nb_* slots.
728 This fixes a number of minor bugs (see bug #624807).
729
Neal Norwitz74a032e2003-01-10 23:29:48 +0000730- Fix problem with dynamic loading on 64-bit AIX (see bug #639945).
731
Tim Petersaf8446f2001-12-21 21:36:50 +0000732Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000733-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000734
Raymond Hettinger9543b342003-01-18 23:22:20 +0000735- Added three operators to the operator module:
736 operator.pow(a,b) which is equivalent to: a**b.
737 operator.is_(a,b) which is equivalent to: a is b.
738 operator.is_not(a,b) which is equivalent to: a is not b.
739
Martin v. Löwis24a880b2002-12-31 12:55:15 +0000740- posix.openpty now works on all systems that have /dev/ptmx.
741
Guido van Rossuma3b89532002-12-30 22:59:32 +0000742- A module zipimport exists to support importing code from zip
743 archives.
744
Tim Peterse820cb62002-12-16 20:57:22 +0000745- The new datetime module supplies classes for manipulating dates and
746 times. The basic design came from the Zope "fishbowl process", and
747 favors practical commercial applications over calendar esoterica. See
748
749 http://www.zope.org/Members/fdrake/DateTimeWiki/FrontPage
750
Martin v. Löwisffad6332002-11-26 09:28:05 +0000751- _tkinter now returns Tcl objects, instead of strings. Objects which
752 have Python equivalents are converted to Python objects, other objects
753 are wrapped. This can be configured through the wantobjects method,
Martin v. Löwis8c8aa5d2002-11-26 21:39:48 +0000754 or Tkinter.wantobjects.
Martin v. Löwisffad6332002-11-26 09:28:05 +0000755
Barry Warsawc27f4bd2002-12-30 21:03:26 +0000756- The PyBSDDB wrapper around the Sleepycat Berkeley DB library has
757 been added as the package bsddb. The traditional bsddb module is
758 still available in source code, but not built automatically anymore,
759 and is now named bsddb185. This supports Berkeley DB versions from
Skip Montanaro13b29102003-02-03 15:17:25 +0000760 3.0 to 4.1. For help converting your databases from the old module (which
761 probably used an obsolete version of Berkeley DB) to the new module, see
762 the db2pickle.py and pickle2db.py scripts described in the Tools/Demos
763 section above.
Martin v. Löwisef546b32002-11-19 08:12:57 +0000764
Martin v. Löwis677bde22002-11-23 22:08:15 +0000765- unicodedata was updated to Unicode 3.2. It supports normalization
766 and names for Hangul syllables and CJK unified ideographs.
Martin v. Löwis7d41e292002-11-23 12:22:32 +0000767
Neal Norwitz94a83fd2002-11-02 17:46:24 +0000768- resource.getrlimit() now returns longs instead of ints.
769
Martin v. Löwis080689c2002-10-26 14:42:02 +0000770- readline now dynamically adjusts its input/output stream if
771 sys.stdin/stdout changes.
772
Guido van Rossumba602972002-10-01 18:18:58 +0000773- The _tkinter module (and hence Tkinter) has dropped support for
774 Tcl/Tk 8.0 and 8.1. Only Tcl/Tk versions 8.2, 8.3 and 8.4 are
775 supported.
776
Martin v. Löwis658009a2002-09-16 17:26:24 +0000777- cPickle.BadPickleGet is now a class.
778
Martin v. Löwisa19bfe02002-10-16 18:28:36 +0000779- The time stamps in os.stat_result are floating point numbers
780 after stat_float_times has been called.
Martin v. Löwis94717ed2002-09-09 14:24:16 +0000781
Neal Norwitzb5673922002-09-05 21:48:07 +0000782- If the size passed to mmap.mmap() is larger than the length of the
783 file on non-Windows platforms, a ValueError is raised. [SF bug 585792]
784
Guido van Rossumb57089c2002-08-06 16:20:26 +0000785- The xreadlines module is slated for obsolescence.
786
Guido van Rossum79f0a102002-07-23 03:32:08 +0000787- The strptime function in the time module is now always available (a
788 Python implementation is used when the C library doesn't define it).
789
Guido van Rossum9562bcf2002-06-14 21:31:18 +0000790- The 'new' module is no longer an extension, but a Python module that
791 only exists for backwards compatibility. Its contents are no longer
792 functions but callable type objects.
793
Tim Peters81b92512002-04-29 01:37:32 +0000794- The bsddb.*open functions can now take 'None' as a filename.
Anthony Baxter83888952002-04-23 02:11:05 +0000795 This will create a temporary in-memory bsddb that won't be
Tim Peters81b92512002-04-29 01:37:32 +0000796 written to disk.
Anthony Baxter83888952002-04-23 02:11:05 +0000797
Martin v. Löwisb96152c2002-12-31 13:20:15 +0000798- posix.getloadavg, posix.lchown, posix.killpg, posix.mknod, and
799 posix.getpgid have been added where available.
Martin v. Löwis06a83e92002-04-14 10:19:44 +0000800
Martin v. Löwisf0a46682002-11-03 17:20:12 +0000801- The locale module now exposes the C library's gettext interface. It
802 also has a new function getpreferredencoding.
Martin v. Löwis2e64c342002-03-27 18:49:02 +0000803
Tim Petersfbf74f22002-03-14 19:06:01 +0000804- A security hole ("double free") was found in zlib-1.1.3, a popular
805 third party compression library used by some Python modules. The
806 hole was quickly plugged in zlib-1.1.4, and the Windows build of
807 Python now ships with zlib-1.1.4.
808
Martin v. Löwis688357e2002-04-08 21:28:20 +0000809- pwd, grp, and resource return enhanced tuples now, with symbolic
810 field names.
Martin v. Löwis29001ff2002-03-01 10:47:37 +0000811
Martin v. Löwis99866332002-03-01 10:27:01 +0000812- array.array is now a type object. A new format character
813 'u' indicates Py_UNICODE arrays. For those, .tounicode and
814 .fromunicode methods are available. Arrays now support __iadd__
815 and __imul__.
816
Neal Norwitze790eae2002-01-01 21:14:12 +0000817- dl now builds on every system that has dlfcn.h. Failure in case
Martin v. Löwis93227272002-01-01 20:18:30 +0000818 of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
819 is called.
820
Michael W. Hudson34f20ea2002-05-27 15:08:24 +0000821- signal.sigpending, signal.sigprocmask and signal.sigsuspend have
822 been added where available.
823
Skip Montanaro8e790e72002-09-03 13:25:17 +0000824- The sys module acquired a new attribute, api_version, which evaluates
825 to the value of the PYTHON_API_VERSION macro with which the
826 interpreter was compiled.
827
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000828- Fixed bug #470582: sre module would return a tuple (None, 'a', 'ab')
829 when applying the regular expression '^((a)c)?(ab)$' on 'ab'. It now
830 returns (None, None, 'ab'), as expected. Also fixed handling of
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +0000831 lastindex/lastgroup match attributes in similar cases. For example,
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000832 when running the expression r'(a)(b)?b' over 'ab', lastindex must be
833 1, not 2.
834
Gustavo Niemeyerc523b042002-11-07 03:28:56 +0000835- Fixed bug #581080: sre scanner was not checking the buffer limit
836 before increasing the current pointer. This was creating an infinite
837 loop in the search function, once the pointer exceeded the buffer
838 limit.
839
Thomas Heller95cb7e42002-11-07 16:23:55 +0000840- The os.fdopen function now enforces a file mode starting with the
841 letter 'r', 'w' or 'a', otherwise a ValueError is raised. This fixes
842 bug #623464.
843
Greg Ward6c58d462003-01-03 18:02:15 +0000844- The linuxaudiodev module is now deprecated; it is being replaced by
845 ossaudiodev. The interface has been extended to cover a lot more of
846 OSS (see www.opensound.com), including most DSP ioctls and the
847 OSS mixer API. Documentation forthcoming in 2.3a2.
848
Tim Petersaf8446f2001-12-21 21:36:50 +0000849Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000850-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000851
Guido van Rossum747f8062003-01-03 16:33:49 +0000852- imaplib.py now supports SSL (Tino Lange and Piers Lauder).
853
Just van Rossum5e156ad2002-12-31 16:38:01 +0000854- Freeze's modulefinder.py has been moved to the standard library;
855 slightly improved so it will issue less false missing submodule
856 reports (see sf path #643711 for details). Documentation will follow
857 with Python 2.3a2.
858
Martin v. Löwis96a60e42002-12-31 13:11:54 +0000859- os.path exposes getctime.
860
Raymond Hettingeraf72d522002-12-29 20:14:11 +0000861- unittest.py now has two additional methods called assertAlmostEqual()
862 and failIfAlmostEqual(). They implement an approximate comparision
863 by rounding the difference between the two arguments and comparing
864 the result to zero. Approximate comparision is essential for
865 unit tests of floating point results.
866
Raymond Hettingere11b5102002-12-25 16:37:19 +0000867- calendar.py now depends on the new datetime module rather than
868 the time module. As a result, the range of allowable dates
869 has been increased.
870
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000871- pdb has a new 'j(ump)' command to select the next line to be
872 executed.
873
Thomas Heller1b3b49d2002-12-12 19:13:44 +0000874- The distutils created windows installers now can run a
875 postinstallation script.
876
Martin v. Löwis4581cfa2002-11-22 08:23:09 +0000877- doctest.testmod can now be called without argument, which means to
878 test the current module.
879
Martin v. Löwisf86e8ef2002-11-22 08:08:44 +0000880- When cancelling a server that implemented threading with a keyboard
881 interrupt, the server would shut down but not terminate (waiting on
882 client threads). A new member variable, daemon_threads, was added to
883 the ThreadingMixIn class in SocketServer.py to make it explicit that
884 this behavior needs to be controlled.
885
Guido van Rossum545c2502002-11-15 13:19:58 +0000886- A new module, optparse, provides a fancy alternative to getopt for
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000887 command line parsing. It is a slightly modified version of Greg
Guido van Rossum545c2502002-11-15 13:19:58 +0000888 Ward's Optik package.
889
Raymond Hettinger79947162002-11-15 06:46:14 +0000890- UserDict.py now defines a DictMixin class which defines all dictionary
891 methods for classes that already have a minimum mapping interface.
892 This greatly simplifies writing classes that need to be substitutable
893 for dictionaries (such as the shelve module).
894
895- shelve.py now subclasses from UserDict.DictMixin. Now shelve supports
896 all dictionary methods. This eases the transition to persistent
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000897 storage for scripts originally written with dictionaries in mind.
Raymond Hettinger79947162002-11-15 06:46:14 +0000898
Skip Montanaro3bf99e32002-12-08 18:36:24 +0000899- shelve.open and the various classes in shelve.py now accept an optional
900 binary flag, which defaults to False. If True, the values stored in the
901 shelf are binary pickles.
902
Guido van Rossumfda06742002-11-13 16:29:18 +0000903- A new package, logging, implements the logging API defined by PEP
904 282. The code is written by Vinay Sajip.
905
Walter Dörwald4dbf1922002-11-06 16:53:44 +0000906- StreamReader, StreamReaderWriter and StreamRecoder in the codecs
907 modules are iterators now.
908
Tim Peters9288f952002-11-05 20:38:55 +0000909- gzip.py now handles files exceeding 2GB. Files over 4GB also work
910 now (provided the OS supports it, and Python is configured with large
911 file support), but in that case the underlying gzip file format can
912 record only the least-significant 32 bits of the file size, so that
913 some tools working with gzipped files may report an incorrect file
914 size.
Tim Petersfb0ea522002-11-04 19:50:11 +0000915
Martin v. Löwis74b51ac2002-10-26 14:50:45 +0000916- xml.sax.saxutils.unescape has been added, to replace entity references
917 with their entity value.
918
Martin v. Löwis77ac4292002-10-15 15:11:13 +0000919- Queue.Queue.{put,get} now support an optional timeout argument.
920
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000921- Various features of Tk 8.4 are exposed in Tkinter.py. The multiple
922 option of tkFileDialog is exposed as function askopenfile{,name}s.
Martin v. Löwis2ec36272002-10-13 10:22:08 +0000923
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000924- Various configure methods of Tkinter have been stream-lined, so that
925 tag_configure, image_configure, window_configure now return a
Tim Petersfb0ea522002-11-04 19:50:11 +0000926 dictionary when invoked with no argument.
Martin v. Löwis6ce13152002-10-10 14:36:13 +0000927
Guido van Rossum2b492b62002-10-09 21:40:48 +0000928- Importing the readline module now no longer has the side effect of
929 calling setlocale(LC_CTYPE, ""). The initial "C" locale, or
930 whatever locale is explicitly set by the user, is preserved. If you
931 want repr() of 8-bit strings in your preferred encoding to preserve
932 all printable characters of that encoding, you have to add the
933 following code to your $PYTHONSTARTUP file or to your application's
934 main():
935
936 import locale
937 locale.setlocale(locale.LC_CTYPE, "")
938
Martin v. Löwise9ce0b02002-10-07 13:23:24 +0000939- shutil.move was added. shutil.copytree now reports errors as an
940 exception at the end, instead of printing error messages.
941
Marc-André Lemburg97047e22002-10-04 11:55:21 +0000942- Encoding name normalization was generalized to not only
943 replace hyphens with underscores, but also all other non-alphanumeric
944 characters (with the exception of the dot which is used for Python
945 package names during lookup). The aliases.py mapping was updated
946 to the new standard.
947
Walter Dörwald5ccaf8f2002-09-06 16:15:58 +0000948- mimetypes has two new functions: guess_all_extensions() which
949 returns a list of all known extensions for a mime type, and
950 add_type() which adds one mapping between a mime type and
951 an extension to the database.
952
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000953- New module: sets, defines the class Set that implements a mutable
954 set type using the keys of a dict to represent the set. There's
955 also a class ImmutableSet which is useful when you need sets of sets
956 or when you need to use sets as dict keys, and a class BaseSet which
Raymond Hettingeref8b9c62002-12-09 08:56:06 +0000957 is the base class of the two.
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000958
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000959- Added random.sample(population,k) for random sampling without replacement.
Tim Petersb9099c32002-11-12 22:08:10 +0000960 Returns a k length list of unique elements chosen from the population.
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000961
Tim Peters012c0a32002-08-16 03:40:07 +0000962- random.randrange(-sys.maxint-1, sys.maxint) no longer raises
963 OverflowError. That is, it now accepts any combination of 'start'
964 and 'stop' arguments so long as each is in the range of Python's
965 bounded integers.
966
Raymond Hettinger40f62172002-12-29 23:03:38 +0000967- Thanks to Raymond Hettinger, random.random() now uses a new core
968 generator. The Mersenne Twister algorithm is implemented in C,
969 threadsafe, faster than the previous generator, has an astronomically
970 large period (2**19937-1), creates random floats to full 53-bit
971 precision, and may be the most widely tested random number generator
972 in existence.
973
974 The random.jumpahead(n) method has different semantics for the new
975 generator. Instead of jumping n steps ahead, it uses n and the
976 existing state to create a new state. This means that jumpahead()
977 continues to support multi-threaded code needing generators of
978 non-overlapping sequences. However, it will break code which relies
979 on jumpahead moving a specific number of steps forward.
980
981 The attributes random.whseed and random.__whseed have no meaning for
982 the new generator. Code using these attributes should switch to a
983 new class, random.WichmannHill which is provided for backward
984 compatibility and to make an alternate generator available.
985
Guido van Rossum4a57c332002-08-02 18:05:20 +0000986- New "algorithms" module: heapq, implements a heap queue. Thanks to
987 Kevin O'Connor for the code and François Pinard for an entertaining
988 write-up explaining the theory and practical uses of heaps.
989
Marc-André Lemburg58e2ff22002-07-12 14:40:04 +0000990- New encoding for the Palm OS character set: palmos.
991
Tim Peters943382c2002-07-07 03:59:34 +0000992- binascii.crc32() and the zipfile module had problems on some 64-bit
993 platforms. These have been fixed. On a platform with 8-byte C longs,
994 crc32() now returns a signed-extended 4-byte result, so that its value
995 as a Python int is equal to the value computed a 32-bit platform.
996
Martin v. Löwis7d650ca2002-06-30 15:05:00 +0000997- xml.dom.minidom.toxml and toprettyxml now take an optional encoding
998 argument.
999
Guido van Rossum9f7549b2002-06-10 21:39:42 +00001000- Some fixes in the copy module: when an object is copied through its
1001 __reduce__ method, there was no check for a __setstate__ method on
1002 the result [SF patch 565085]; deepcopy should treat instances of
1003 custom metaclasses the same way it treats instances of type 'type'
1004 [SF patch 560794].
1005
Guido van Rossum5033c8e2002-06-07 12:40:52 +00001006- Sockets now support timeout mode. After s.settimeout(T), where T is
1007 a float expressing seconds, subsequent operations raise an exception
1008 if they cannot be completed within T seconds. To disable timeout
Guido van Rossum79f0a102002-07-23 03:32:08 +00001009 mode, use s.settimeout(None). There's also a module function,
1010 socket.setdefaulttimeout(T), which sets the default for all sockets
1011 created henceforth.
Guido van Rossum5033c8e2002-06-07 12:40:52 +00001012
1013- getopt.gnu_getopt was added. This supports GNU-style option
1014 processing, where options can be mixed with non-option arguments.
Martin v. Löwis446a25f2002-06-06 10:58:36 +00001015
Michael W. Hudsonb0dc1a32002-06-04 18:27:35 +00001016- Stop using strings for exceptions. String objects used for
1017 exceptions are now classes deriving from Exception. The objects
1018 changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
1019 tabnanny.NannyNag, and xdrlib.Error.
Neal Norwitzb5b5a262002-06-04 17:14:07 +00001020
Walter Dörwald474458d2002-06-04 15:16:29 +00001021- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
1022 BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
1023 Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
1024 big endian systems were added to the codecs module. The old names
1025 BOM32_* and BOM64_* were off by a factor of 2.
1026
Guido van Rossumf9257822002-06-18 20:43:18 +00001027- Added conversion functions math.degrees() and math.radians().
Raymond Hettinger87f59ee2002-05-13 04:17:32 +00001028
Raymond Hettinger866964c2002-12-14 19:51:34 +00001029- math.log() now takes an optional argument: math.log(x[, base]).
1030
Raymond Hettinger9b1df1d2002-05-12 06:07:21 +00001031- ftplib.retrlines() now tests for callback is None rather than testing
1032 for False. Was causing an error when given a callback object which
1033 was callable but also returned len() as zero. The change may
1034 create new breakage if the caller relied on the undocumented behavior
1035 and called with callback set to [] or some other False value not
1036 identical to None.
1037
Tim Peters46c04e12002-05-05 20:40:00 +00001038- random.gauss() uses a piece of hidden state used by nothing else,
1039 and the .seed() and .whseed() methods failed to reset it. In other
1040 words, setting the seed didn't completely determine the sequence of
1041 results produced by random.gauss(). It does now. Programs repeatedly
1042 mixing calls to a seed method with calls to gauss() may see different
1043 results now.
1044
Fred Drake7f781c92002-05-01 20:33:53 +00001045- The pickle.Pickler class grew a clear_memo() method to mimic that
1046 provided by cPickle.Pickler.
1047
Tim Peters81b92512002-04-29 01:37:32 +00001048- difflib's SequenceMatcher class now does a dynamic analysis of
1049 which elements are so frequent as to constitute noise. For
1050 comparing files as sequences of lines, this generally works better
1051 than the IS_LINE_JUNK function, and function ndiff's linejunk
1052 argument defaults to None now as a result. A happy benefit is
1053 that SequenceMatcher may run much faster now when applied
1054 to large files with many duplicate lines (for example, C program
1055 text with lots of repeated "}" and "return NULL;" lines).
1056
Guido van Rossum256705b2002-04-23 13:29:43 +00001057- New Text.dump() method in Tkinter module.
1058
Marc-André Lemburg1ec71ea2002-04-17 20:33:40 +00001059- New distutils commands for building packagers were added to
1060 support pkgtool on Solaris and swinstall on HP-UX.
1061
1062- distutils now has a new abstract binary packager base class
1063 command/bdist_packager, which simplifies writing packagers.
1064 This will hopefully provide the missing bits to encourage
1065 people to submit more packagers, e.g. for Debian, FreeBSD
1066 and other systems.
1067
Guido van Rossumf9257822002-06-18 20:43:18 +00001068- The UTF-16, -LE and -BE stream readers now raise a
1069 NotImplementedError for all calls to .readline(). Previously, they
1070 used to just produce garbage or fail with an encoding error --
1071 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 +00001072 work well with these.
1073
Martin v. Löwis5c137c22002-03-18 12:44:08 +00001074- compileall now supports quiet operation.
1075
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001076- The BaseHTTPServer now implements optional HTTP/1.1 persistent
Martin v. Löwis587c98c2002-03-17 18:37:22 +00001077 connections.
1078
Marc-André Lemburga5d2b4c2002-02-16 18:23:30 +00001079- socket module: the SSL support was broken out of the main
1080 _socket module C helper and placed into a new _ssl helper
1081 which now gets imported by socket.py if available and working.
1082
Marc-André Lemburg37aa5802002-02-10 21:42:47 +00001083- encodings package: added aliases for all supported IANA character
1084 sets
1085
Guido van Rossum606fe4e2001-12-28 20:57:14 +00001086- ftplib: to safeguard the user's privacy, anonymous login will use
1087 "anonymous@" as default password, rather than the real user and host
1088 name.
1089
Fred Drake36736122002-01-10 13:50:31 +00001090- webbrowser: tightened up the command passed to os.system() so that
1091 arbitrary shell code can't be executed because a bogus URL was
1092 passed in.
1093
Tim Peters11bd9942002-02-01 00:52:29 +00001094- gettext.translation has an optional fallback argument, and
Martin v. Löwisa55ffae2002-01-11 06:58:49 +00001095 gettext.find an optional all argument. Translations will now fallback
Martin v. Löwisd8996052002-11-21 21:45:32 +00001096 on a per-message basis. The module supports plural forms, by means
1097 of gettext.[d]ngettext and Translation.[u]ngettext.
Martin v. Löwis1be64192002-01-11 06:33:28 +00001098
Martin v. Löwis9668b932002-01-12 11:27:42 +00001099- distutils bdist commands now offer a --skip-build option.
1100
Walter Dörwaldb25c2b02002-03-21 10:38:40 +00001101- warnings.warn now accepts a Warning instance as first argument.
1102
Fred Drakefed7e852002-04-04 19:36:15 +00001103- The xml.sax.expatreader.ExpatParser class will no longer create
1104 circular references by using itself as the locator that gets passed
1105 to the content handler implementation. [SF bug #535474]
1106
Barry Warsaw47f3e2c2002-05-20 00:14:24 +00001107- The email.Parser.Parser class now properly parses strings regardless
1108 of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
1109 or CRLF). Also, the Header class's constructor default arguments
1110 has changed slightly so that an explicit maxlinelen value is always
Barry Warsaw497e5c42002-12-30 19:27:08 +00001111 honored, and so unicode conversion error handling can be specified.
Barry Warsaw47f3e2c2002-05-20 00:14:24 +00001112
David Goodgerf349e262003-01-03 03:30:21 +00001113- distutils' build_ext command now links C++ extensions with the C++
Gustavo Niemeyerf8ca8362002-11-05 16:50:05 +00001114 compiler available in the Makefile or CXX environment variable, if
David Goodgerf349e262003-01-03 03:30:21 +00001115 running under \*nix.
Gustavo Niemeyerf8ca8362002-11-05 16:50:05 +00001116
1117- New module bz2: provides a comprehensive interface for the bz2 compression
1118 library. It implements a complete file interface, one-shot (de)compression
1119 functions, and types for sequential (de)compression.
1120
David Goodgerf349e262003-01-03 03:30:21 +00001121- New pdb command 'pp' which is like 'p' except that it pretty-prints
Barry Warsaw5d8d6182002-11-05 22:41:33 +00001122 the value of its expression argument.
1123
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +00001124- Now bdist_rpm distutils command understands a verify_script option in
1125 the config file, including the contents of the referred filename in
1126 the "%verifyscript" section of the rpm spec file.
1127
Gustavo Niemeyer1456fde2002-11-25 17:25:04 +00001128- Fixed bug #495695: webbrowser module would run graphic browsers in a
1129 unix environment even if DISPLAY was not set. Also, support for
1130 skipstone browser was included.
1131
Gustavo Niemeyerd5ae01a2002-12-16 13:11:57 +00001132- Fixed bug #636769: rexec would run unallowed code if subclasses of
1133 strings were used as parameters for certain functions.
1134
Tim Petersaf8446f2001-12-21 21:36:50 +00001135Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001136-----------
Tim Petersaf8446f2001-12-21 21:36:50 +00001137
Martin v. Löwis0d1fdea2002-11-22 08:36:54 +00001138- pygettext.py now supports globbing on Windows, and accepts module
1139 names in addition to accepting file names.
1140
Guido van Rossum923e4ef2002-09-17 20:58:59 +00001141- The SGI demos (Demo/sgi) have been removed. Nobody thought they
1142 were interesting any more. (The SGI library modules and extensions
1143 are still there; it is believed that at least some of these are
1144 still used and useful.)
1145
Fred Drake40813b12002-08-05 15:24:19 +00001146- IDLE supports the new encoding declarations (PEP 263); it can also
1147 deal with legacy 8-bit files if they use the locale's encoding. It
1148 allows non-ASCII strings in the interactive shell and executes them
1149 in the locale's encoding.
Martin v. Löwis98ce7b72002-08-05 15:11:26 +00001150
Marc-André Lemburg46260092002-04-04 16:17:11 +00001151- freeze.py now produces binaries which can import shared modules,
1152 unlike before when this failed due to missing symbol exports in
1153 the generated binary.
1154
Tim Petersaf8446f2001-12-21 21:36:50 +00001155Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001156-----
Tim Petersaf8446f2001-12-21 21:36:50 +00001157
Martin v. Löwisdc461752002-11-06 21:59:33 +00001158- On Unix, IDLE is now installed automatically.
1159
Guido van Rossum6b3db552002-09-25 15:02:44 +00001160- The fpectl module is not built by default; it's dangerous or useless
1161 except in the hands of experts.
1162
Tim Petersf47630f2002-08-01 02:34:51 +00001163- The public Python C API will generally be declared using PyAPI_FUNC
Guido van Rossum6b3db552002-09-25 15:02:44 +00001164 and PyAPI_DATA macros, while Python extension module init functions
1165 will be declared with PyMODINIT_FUNC. DL_EXPORT/DL_IMPORT macros
1166 are deprecated.
Neal Norwitz1389f3e2002-07-22 13:21:10 +00001167
Tim Petersc6a3ff62002-07-08 22:11:52 +00001168- A bug was fixed that could cause COUNT_ALLOCS builds to segfault, or
1169 get into infinite loops, when a new-style class got garbage-collected.
1170 Unfortunately, to avoid this, the way COUNT_ALLOCS works requires
1171 that new-style classes be immortal in COUNT_ALLOCS builds. Note that
1172 COUNT_ALLOCS is not enabled by default, in either release or debug
1173 builds, and that new-style classes are immortal only in COUNT_ALLOCS
1174 builds.
1175
Tim Peters943382c2002-07-07 03:59:34 +00001176- Compiling out the cyclic garbage collector is no longer an option.
1177 The old symbol WITH_CYCLE_GC is now ignored, and Python.h arranges
1178 that it's always defined (for the benefit of any extension modules
1179 that may be conditionalizing on it). A bonus is that any extension
1180 type participating in cyclic gc can choose to participate in the
1181 Py_TRASHCAN mechanism now too; in the absence of cyclic gc, this used
1182 to require editing the core to teach the trashcan mechanism about the
1183 new type.
1184
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +00001185- According to Annex F of the current C standard,
Tim Peters1de41bf2002-07-03 03:31:20 +00001186
1187 The Standard C macro HUGE_VAL and its float and long double analogs,
1188 HUGE_VALF and HUGE_VALL, expand to expressions whose values are
1189 positive infinities.
1190
1191 Python only uses the double HUGE_VAL, and only to #define its own symbol
1192 Py_HUGE_VAL. Some platforms have incorrect definitions for HUGE_VAL.
1193 pyport.h used to try to worm around that, but the workarounds triggered
1194 other bugs on other platforms, so we gave up. If your platform defines
1195 HUGE_VAL incorrectly, you'll need to #define Py_HUGE_VAL to something
1196 that works on your platform. The only instance of this I'm sure about
1197 is on an unknown subset of Cray systems, described here:
1198
1199 http://www.cray.com/swpubs/manuals/SN-2194_2.0/html-SN-2194_2.0/x3138.htm
1200
1201 Presumably 2.3a1 breaks such systems. If anyone uses such a system, help!
1202
Martin v. Löwisa3fb4f72002-06-09 13:33:54 +00001203- The configure option --without-doc-strings can be used to remove the
1204 doc strings from the builtin functions and modules; this reduces the
1205 size of the executable.
1206
Guido van Rossumadd88062002-08-15 14:01:14 +00001207- The universal newlines option (PEP 278) is on by default. On Unix
1208 it can be disabled by passing --without-universal-newlines to the
1209 configure script. On other platforms, remove
1210 WITH_UNIVERSAL_NEWLINES from pyconfig.h.
Tim Peters639295f2002-04-21 07:30:30 +00001211
Martin v. Löwis1142de32002-03-29 16:28:31 +00001212- On Unix, a shared libpython2.3.so can be created with --enable-shared.
1213
Tim Peters8deda702002-03-30 10:06:07 +00001214- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
1215 preprocessor symbols were eliminated. The internal decisions they
1216 controlled stopped being experimental long ago.
Tim Peters1f7df352002-03-29 03:29:08 +00001217
Fred Drake7d28b732002-05-02 21:17:00 +00001218- The tools used to build the documentation now work under Cygwin as
1219 well as Unix.
1220
Skip Montanaro57454e52002-06-14 20:30:31 +00001221- The bsddb and dbm module builds have been changed to try and avoid version
1222 skew problems and disable linkage with Berkeley DB 1.85 unless the
1223 installer knows what s/he's doing. See the section on building these
1224 modules in the README file for details.
1225
Tim Petersaf8446f2001-12-21 21:36:50 +00001226C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001227-----
Tim Petersaf8446f2001-12-21 21:36:50 +00001228
Neil Schemenauer6c194762002-11-18 16:19:39 +00001229- PyNumber_Check() now returns true for string and unicode objects.
1230 This is a result of these types having a partially defined
Guido van Rossum1d267402002-11-18 16:27:16 +00001231 tp_as_number slot. (This is not a feature, but an indication that
Walter Dörwalda1a61f92002-11-19 21:20:25 +00001232 PyNumber_Check() is not very useful to determine numeric behavior.
Guido van Rossum1d267402002-11-18 16:27:16 +00001233 It may be deprecated.)
Neil Schemenauer6c194762002-11-18 16:19:39 +00001234
Guido van Rossum45ec02a2002-08-19 21:43:18 +00001235- The string object's layout has changed: the pointer member
1236 ob_sinterned has been replaced by an int member ob_sstate. On some
1237 platforms (e.g. most 64-bit systems) this may change the offset of
1238 the ob_sval member, so as a precaution the API_VERSION has been
1239 incremented. The apparently unused feature of "indirect interned
1240 strings", supported by the ob_sinterned member, is gone. Interned
1241 strings are now usually mortal; theres a new API,
1242 PyString_InternImmortal() that creates immortal interned strings.
1243 (The ob_sstate member can only take three values; however, while
1244 making it a char saves a few bytes per string object on average, in
1245 it also slowed things down a bit because ob_sval was no longer
1246 aligned.)
1247
Guido van Rossumfdb86482002-08-14 21:20:32 +00001248- The Py_InitModule*() functions now accept NULL for the 'methods'
1249 argument. Modules without global functions are becoming more common
1250 now that factories can be types rather than functions.
1251
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +00001252- New C API PyUnicode_FromOrdinal() which exposes unichr() at C
1253 level.
1254
Thomas Heller085358a2002-07-29 14:27:41 +00001255- New functions PyErr_SetExcFromWindowsErr() and
1256 PyErr_SetExcFromWindowsErrWithFilename(). Similar to
1257 PyErr_SetFromWindowsErrWithFilename() and
1258 PyErr_SetFromWindowsErr(), but they allow to specify
1259 the exception type to raise. Available on Windows.
1260
Tim Peters7c321a82002-07-09 02:57:01 +00001261- Py_FatalError() is now declared as taking a const char* argument. It
1262 was previously declared without const. This should not affect working
1263 code.
1264
Martin v. Löwis01f94bd2002-05-08 08:44:21 +00001265- Added new macro PySequence_ITEM(o, i) that directly calls
1266 sq_item without rechecking that o is a sequence and without
1267 adjusting for negative indices.
1268
Fred Draked0ba6362002-05-02 21:28:26 +00001269- PyRange_New() now raises ValueError if the fourth argument is not 1.
1270 This is part of the removal of deprecated features of the xrange
1271 object.
1272
Guido van Rossum517c7d42002-04-26 02:49:14 +00001273- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
1274 coercion if both arguments have the same type but this type has the
1275 CHECKTYPES flag set. This is to better support proxies.
1276
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00001277- The type of tp_free has been changed from "``void (*)(PyObject *)``" to
1278 "``void (*)(void *)``".
Neil Schemenauer9344b142002-04-12 23:00:08 +00001279
1280- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
1281
Guido van Rossum0986d822002-04-08 01:38:42 +00001282- A type can now inherit its metatype from its base type. Previously,
1283 when PyType_Ready() was called, if ob_type was found to be NULL, it
1284 was always set to &PyType_Type; now it is set to base->ob_type,
1285 where base is tp_base, defaulting to &PyObject_Type.
1286
1287- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
1288
Neil Schemenauerc9abc1d2002-05-08 14:14:41 +00001289- The PyCore_* family of APIs have been removed.
Neil Schemenauer9d50d132002-03-22 17:06:59 +00001290
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001291- The "u#" parser marker will now pass through Unicode objects as-is
Marc-André Lemburg3e3eacb2002-01-09 16:21:27 +00001292 without going through the buffer API.
1293
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001294- The enumerators of cmp_op have been renamed to use the prefix ``PyCmp_``.
Martin v. Löwis7198a522002-01-01 19:59:11 +00001295
Tim Peters10a3bb52001-12-25 19:07:38 +00001296- An old #define of ANY as void has been removed from pyport.h. This
1297 hasn't been used since Python's pre-ANSI days, and the #define has
1298 been marked as obsolete since then. SF bug 495548 says it created
1299 conflicts with other packages, so keeping it around wasn't harmless.
1300
Tim Petersaf8446f2001-12-21 21:36:50 +00001301- Because Python's magic number scheme broke on January 1st, we decided
1302 to stop Python development. Thanks for all the fish!
1303
Tim Petersfb05db22002-03-11 00:24:00 +00001304- Some of us don't like fish, so we changed Python's magic number
Marc-André Lemburge92e0a92002-02-09 11:28:43 +00001305 scheme to a new one. See Python/import.c for details.
1306
Tim Petersaf8446f2001-12-21 21:36:50 +00001307New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001308-------------
Tim Petersaf8446f2001-12-21 21:36:50 +00001309
Martin v. Löwis79acb9e2002-12-06 12:48:53 +00001310- OpenVMS is now supported.
1311
Martin v. Löwisf90ae202002-06-11 06:22:31 +00001312- AtheOS is now supported.
1313
Andrew MacIntyre161ad0e2002-08-04 07:25:58 +00001314- the EMX runtime environment on OS/2 is now supported.
1315
Martin v. Löwisa6e97582002-01-01 18:41:33 +00001316- GNU/Hurd is now supported.
1317
Tim Petersaf8446f2001-12-21 21:36:50 +00001318Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001319-----
1320
Fred Drake4dd0f7e2002-11-26 21:44:56 +00001321- The regrtest.py script's -u option now provides a way to say "allow
1322 all resources except this one." For example, to allow everything
1323 except bsddb, give the option '-uall,-bsddb'.
Tim Petersaf8446f2001-12-21 21:36:50 +00001324
1325Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001326-------
Tim Petersaf8446f2001-12-21 21:36:50 +00001327
Tim Peters19cf4ee2002-11-23 03:49:08 +00001328- The Windows distribution now ships with version 4.0.14 of the
1329 Sleepycat Berkeley database library. This should be a huge
1330 improvement over the previous Berkeley DB 1.85, which had many
1331 bugs.
1332 XXX What are the licensing issues here?
Tim Peters84c7a3f2002-11-23 18:48:06 +00001333 XXX If a user has a database created with a previous verion of
1334 XXX Python, what must they do to convert it?
1335 XXX I'm still not sure how to link this thing (see PCbuild/readme.txt).
Tim Peters19cf4ee2002-11-23 03:49:08 +00001336 XXX The version # is likely to change before 2.3a1.
Tim Peterse820cb62002-12-16 20:57:22 +00001337
1338- The Windows distribution now ships with a Secure Sockets Library (SLL)
Mark Hammondc3de0082002-12-03 06:16:08 +00001339 module (_ssl.pyd)
Tim Peters19cf4ee2002-11-23 03:49:08 +00001340
Tim Peters857fb4c2002-11-14 23:31:58 +00001341- The Windows distribution now ships with Tcl/Tk version 8.4.1 (it
1342 previously shipped with Tcl/Tk 8.3.2).
1343
Tim Peters37dfb012002-11-11 19:51:33 +00001344- When Python is built under a Microsoft compiler, sys.version now
1345 includes the compiler version number (_MSC_VER). For example, under
1346 MSVC 6, sys.version constains the substring "MSC v.1200 ". 1200 is
1347 the value of _MSC_VER under MSVC 6.
1348
Tim Peters08e72952002-04-16 20:48:01 +00001349- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
1350 of that has been fixed in the installer (disabled Wise's "delete in-
1351 use files" uninstall option).
1352
Guido van Rossum181e41a2002-04-06 00:23:25 +00001353- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
1354
Tim Peters33187922002-04-04 20:02:04 +00001355- The installer now installs Start menu shortcuts under (the local
1356 equivalent of) "All Users" when doing an Admin install.
1357
Tim Petersfb05db22002-03-11 00:24:00 +00001358- file.truncate([newsize]) now works on Windows for all newsize values.
1359 It used to fail if newsize didn't fit in 32 bits, reflecting a
1360 limitation of MS _chsize (which is no longer used).
1361
Tim Petersab034fa2002-02-01 11:27:43 +00001362- os.waitpid() is now implemented for Windows, and can be used to block
1363 until a specified process exits. This is similar to, but not exactly
1364 the same as, os.waitpid() on POSIX systems. If you're waiting for
1365 a specific process whose pid was obtained from one of the spawn()
1366 functions, the same Python os.waitpid() code works across platforms.
Tim Peters33187922002-04-04 20:02:04 +00001367 See the docs for details. The docs were changed to clarify that
1368 spawn functions return, and waitpid requires, a process handle on
1369 Windows (not the same thing as a Windows process id).
Tim Petersab034fa2002-02-01 11:27:43 +00001370
Tim Peters11bd9942002-02-01 00:52:29 +00001371- New tempfile.TemporaryFile implementation for Windows: this doesn't
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001372 need a TemporaryFileWrapper wrapper anymore, and should be immune
Tim Peters11bd9942002-02-01 00:52:29 +00001373 to a nasty problem: before 2.3, if you got a temp file on Windows, it
1374 got wrapped in an object whose close() method first closed the
1375 underlying file, then deleted the file. This usually worked fine.
1376 However, the spawn family of functions on Windows create (at a low C
1377 level) the same set of open files in the spawned process Q as were
1378 open in the spawning process P. If a temp file f was among them, then
1379 doing f.close() in P first closed P's C-level file handle on f, but Q's
1380 C-level file handle on f remained open, so the attempt in P to delete f
1381 blew up with a "Permission denied" error (Windows doesn't allow
1382 deleting open files). This was surprising, subtle, and difficult to
1383 work around.
1384
1385- The os module now exports all the symbolic constants usable with the
1386 low-level os.open() on Windows: the new constants in 2.3 are
1387 O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
1388 The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
1389 O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
1390 to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
1391 (so specify both if you want both; note that neither is useful unless
1392 specified with O_CREAT too).
1393
Tim Petersaf8446f2001-12-21 21:36:50 +00001394Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001395----
1396
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001397- Mac/Relnotes is gone, the release notes are now here.
Tim Petersaf8446f2001-12-21 21:36:50 +00001398
Just van Rossume1ebd802003-02-10 10:06:18 +00001399- Python (the OSX-only, unix-based version, not the OS9-compatible CFM
1400 version) now fully supports unicode strings as arguments to various file
1401 system calls, eg. open(), file(), os.stat() and os.listdir().
1402
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001403- The current naming convention for Python on the Macintosh is that MacPython
1404 refers to the unix-based OSX-only version, and MacPython-OS9 refers to the
1405 CFM-based version that runs on both OS9 and OSX.
1406
1407- All MacPython-OS9 functionality is now available in an OSX unix build,
1408 including the Carbon modules, the IDE, OSA support, etc. A lot of this
1409 will only work correctly in a framework build, though, because you cannot
1410 talk to the window manager unless your application is run from a .app
1411 bundle. There is a command line tool "pythonw" that runs your script
1412 with an interpreter living in such a .app bundle, this interpreter should
1413 be used to run any Python script using the window manager (including
1414 Tkinter or wxPython scripts).
Tim Petersbbc5d162003-01-02 16:02:27 +00001415
Jack Jansen8bb80db2002-12-30 22:42:43 +00001416- Most of Mac/Lib has moved to Lib/plat-mac, which is again used both in
1417 MacPython-OSX and MacPython-OS9. The only modules remaining in Mac/Lib
1418 are specifically for MacPython-OS9 (CFM support, preference resources, etc).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001419
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001420- A new utility PythonLauncher will start a Python interpreter when a .py or
1421 .pyw script is double-clicked in the Finder. By default .py scripts are
1422 run with a normal Python interpreter in a Terminal window and .pyw
1423 files are run with a window-aware pythonw interpreter without a Terminal
1424 window, but all this can be customized.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001425
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001426- MacPython-OS9 is now Carbon-only, so it runs on Mac OS 9 or Mac OS X and
1427 possibly on Mac OS 8.6 with the right CarbonLib installed, but not on earlier
1428 releases.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001429
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001430- Many tools such as BuildApplet.py and gensuitemodule.py now support a command
1431 line interface too.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001432
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001433- All the Carbon classes are now PEP253 compliant, meaning that you can
1434 subclass them from Python. Most of the attributes have gone, you should
1435 now use the accessor function call API, which is also what Apple's
1436 documentation uses. Some attributes such as grafport.visRgn are still
1437 available for convenience.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001438
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001439- New Carbon modules File (implementing the APIs in Files.h and Aliases.h)
1440 and Folder (APIs from Folders.h). The old macfs builtin module is
1441 gone, and replaced by a Python wrapper around the new modules.
1442
1443- Pathname handling should now be fully consistent: MacPython-OSX always uses
1444 unix pathnames and MacPython-OS9 always uses colon-separated Mac pathnames
1445 (also when running on Mac OS X).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001446
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001447- New Carbon modules Help and AH give access to the Carbon Help Manager.
1448 There are hooks in the IDE to allow accessing the Python documentation
1449 (and Apple's Carbon and Cocoa documentation) through the Help Viewer.
1450 See Mac/OSX/README for converting the Python documentation to a
1451 Help Viewer comaptible form and installing it.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001452
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001453- OSA support has been redesigned and the generated Python classes now
1454 mirror the inheritance defined by the underlying OSA classes.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001455
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001456- MacPython no longer maps both \r and \n to \n on input for any text file.
1457 This feature has been replaced by universal newline support (PEP278).
Tim Peters0bf60bd2003-01-08 20:40:01 +00001458
Jack Jansen05d284b2003-01-08 16:29:17 +00001459- The default encoding for Python sourcefiles in MacPython-OS9 is no longer
1460 mac-roman (or whatever your local Mac encoding was but "ascii", like on
1461 other platforms. If you really need sourcefiles with Mac characters in them
1462 you can change this in site.py.
Tim Petersaf8446f2001-12-21 21:36:50 +00001463
Tim Peters909c0912001-12-14 23:16:18 +00001464What's New in Python 2.2 final?
Tim Peters909c0912001-12-14 23:16:18 +00001465===============================
1466
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001467*Release date: 21-Dec-2001*
1468
Tim Peters909c0912001-12-14 23:16:18 +00001469Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001470--------------------------------------------
Tim Peters909c0912001-12-14 23:16:18 +00001471
Barry Warsaw52acb492001-12-21 20:04:22 +00001472- pickle.py, cPickle: allow pickling instances of new-style classes
1473 with a custom metaclass.
1474
Tim Peters909c0912001-12-14 23:16:18 +00001475Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001476-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001477
Barry Warsaw52acb492001-12-21 20:04:22 +00001478- weakref proxy object: when comparing, unwrap both arguments if both
1479 are proxies.
1480
Tim Peters909c0912001-12-14 23:16:18 +00001481Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001482-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001483
Barry Warsaw52acb492001-12-21 20:04:22 +00001484- binascii.b2a_base64(): fix a potential buffer overrun when encoding
1485 very short strings.
1486
1487- cPickle: the obscure "fast" mode was suspected of causing stack
1488 overflows on the Mac. Hopefully fixed this by setting the recursion
1489 limit much smaller. If the limit is too low (it only affects
1490 performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
1491 when compiling cPickle.c (or in pyconfig.h).
1492
Tim Peters909c0912001-12-14 23:16:18 +00001493Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001494-------
Tim Peters909c0912001-12-14 23:16:18 +00001495
Barry Warsaw52acb492001-12-21 20:04:22 +00001496- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
1497 close or delete time).
1498
1499- rfc822.py: fixed a bug where the address '<>' was converted to None
1500 instead of an empty string (also fixes the email.Utils module).
1501
1502- xmlrpclib.py: version 1.0.0; uses precision for doubles.
1503
1504- test suite: the pickle and cPickle tests were not executing any code
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001505 when run from the standard regression test.
Barry Warsaw52acb492001-12-21 20:04:22 +00001506
Tim Peters909c0912001-12-14 23:16:18 +00001507Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001508-----------
Tim Peters909c0912001-12-14 23:16:18 +00001509
1510Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001511-----
Tim Peters909c0912001-12-14 23:16:18 +00001512
1513C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001514-----
Tim Peters909c0912001-12-14 23:16:18 +00001515
1516New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001517-------------
Tim Peters909c0912001-12-14 23:16:18 +00001518
1519Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001520-----
Tim Peters909c0912001-12-14 23:16:18 +00001521
1522Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001523-------
Tim Peters909c0912001-12-14 23:16:18 +00001524
Barry Warsaw52acb492001-12-21 20:04:22 +00001525- distutils package: fixed broken Windows installers (bdist_wininst).
1526
1527- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
1528 instances are deleted at process exit time.
1529
1530- socket.py: prevent mysterious warnings when socket instances are
1531 deleted at process exit time.
1532
1533- posixmodule.c: fix a Windows crash with stat() of a filename ending
1534 in backslash.
1535
Tim Peters909c0912001-12-14 23:16:18 +00001536Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001537----
Tim Peters909c0912001-12-14 23:16:18 +00001538
Barry Warsaw52acb492001-12-21 20:04:22 +00001539- The Carbon toolbox modules have been upgraded to Universal Headers
1540 3.4, and experimental CoreGraphics and CarbonEvents modules have
1541 been added. All only for framework-enabled MacOSX.
1542
Tim Peters909c0912001-12-14 23:16:18 +00001543
Tim Peters6272dfd2001-12-13 19:34:00 +00001544What's New in Python 2.2c1?
Tim Petersb3c9af12001-11-17 00:21:57 +00001545===========================
1546
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001547*Release date: 14-Dec-2001*
1548
Tim Petersb3c9af12001-11-17 00:21:57 +00001549Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001550--------------------------------------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001551
Barry Warsaw06557452001-12-14 20:47:12 +00001552- Guido's tutorial introduction to the new type/class features has
1553 been extensively updated. See
1554
1555 http://www.python.org/2.2/descrintro.html
1556
1557 That remains the primary documentation in this area.
1558
Guido van Rossum33bab012001-12-05 22:45:48 +00001559- Fixed a leak: instance variables declared with __slots__ were never
1560 deleted!
1561
Guido van Rossum4b800852001-12-03 00:54:52 +00001562- The "delete attribute" method of descriptor objects is called
1563 __delete__, not __del__. In previous releases, it was mistakenly
1564 called __del__, which created an unfortunate overloading condition
1565 with finalizers. (The "get attribute" and "set attribute" methods
1566 are still called __get__ and __set__, respectively.)
1567
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001568- Some subtle issues with the super built-in were fixed:
1569
1570 (a) When super itself is subclassed, its __get__ method would still
1571 return an instance of the base class (i.e., of super).
1572
1573 (b) super(C, C()).__class__ would return C rather than super. This
1574 is confusing. To fix this, I decided to change the semantics of
1575 super so that it only applies to code attributes, not to data
1576 attributes. After all, overriding data attributes is not
1577 supported anyway.
1578
1579 (c) The __get__ method didn't check whether the argument was an
1580 instance of the type used in creation of the super instance.
1581
Guido van Rossumcd7b7d62001-12-04 21:02:07 +00001582- Previously, hash() of an instance of a subclass of a mutable type
1583 (list or dictionary) would return some value, rather than raising
1584 TypeError. This has been fixed. Also, directly calling
1585 dict.__hash__ and list.__hash__ now raises the same TypeError
1586 (previously, these were the same as object.__hash__).
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001587
Guido van Rossumd331cb52001-12-05 19:46:42 +00001588- New-style objects now support deleting their __dict__. This is for
1589 all intents and purposes equivalent to assigning a brand new empty
1590 dictionary, but saves space if the object is not used further.
1591
Tim Petersb3c9af12001-11-17 00:21:57 +00001592Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001593-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001594
Tim Peters3caca232001-12-06 06:23:26 +00001595- -Qnew now works as documented in PEP 238: when -Qnew is passed on
1596 the command line, all occurrences of "/" use true division instead
1597 of classic division. See the PEP for details. Note that "all"
1598 means all instances in library and 3rd-party modules, as well as in
1599 your own code. As the PEP says, -Qnew is intended for use only in
1600 educational environments with control over the libraries in use.
Tim Petersbf72fe22001-12-11 21:43:14 +00001601 Note that test_coercion.py in the standard Python test suite fails
1602 under -Qnew; this is expected, and won't be repaired until true
1603 division becomes the default (in the meantime, test_coercion is
1604 testing the current rules).
Tim Peters3caca232001-12-06 06:23:26 +00001605
Fred Drake6c01e252001-12-14 17:08:12 +00001606- complex() now only allows the first argument to be a string
1607 argument, and raises TypeError if either the second arg is a string
1608 or if the second arg is specified when the first is a string.
1609
Tim Petersb3c9af12001-11-17 00:21:57 +00001610Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001611-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001612
Martin v. Löwis560da622001-11-24 09:24:51 +00001613- gc.get_referents was renamed to gc.get_referrers.
1614
Tim Petersb3c9af12001-11-17 00:21:57 +00001615Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001616-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001617
Tim Peters25059d32001-12-07 20:35:43 +00001618- Functions in the os.spawn() family now release the global interpreter
1619 lock around calling the platform spawn. They should always have done
1620 this, but did not before 2.2c1. Multithreaded programs calling
1621 an os.spawn function with P_WAIT will no longer block all Python threads
1622 until the spawned program completes. It's possible that some programs
1623 relies on blocking, although more likely by accident than by design.
1624
Martin v. Löwis3a89b2b2001-11-25 14:35:58 +00001625- webbrowser defaults to netscape.exe on OS/2 now.
1626
Martin v. Löwis652e1912001-11-25 14:50:56 +00001627- Tix.ResizeHandle exposes detach_widget, hide, and show.
1628
Martin v. Löwis714d2e22001-12-02 12:26:03 +00001629- The charset alias windows_1252 has been added.
1630
Barry Warsaw06557452001-12-14 20:47:12 +00001631- types.StringTypes is a tuple containing the defined string types;
1632 usually this will be (str, unicode), but if Python was compiled
1633 without Unicode support it will be just (str,).
1634
1635- The pulldom and minidom modules were synchronized to PyXML.
1636
Tim Petersb3c9af12001-11-17 00:21:57 +00001637Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001638-----------
Tim Petersb3c9af12001-11-17 00:21:57 +00001639
Barry Warsaw06557452001-12-14 20:47:12 +00001640- A new script called Tools/scripts/google.py was added, which fires
1641 off a search on Google.
1642
Tim Petersb3c9af12001-11-17 00:21:57 +00001643Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001644-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001645
Barry Warsaw06557452001-12-14 20:47:12 +00001646- Note that release builds of Python should arrange to define the
1647 preprocessor symbol NDEBUG on the command line (or equivalent).
1648 In the 2.2 pre-release series we tried to define this by magic in
1649 Python.h instead, but it proved to cause problems for extension
1650 authors. The Unix, Windows and Mac builds now all define NDEBUG in
1651 release builds via cmdline (or equivalent) instead. Ports to
1652 other platforms should do likewise.
1653
Jack Jansen1999ef42001-12-06 21:47:20 +00001654- It is no longer necessary to use --with-suffix when building on a
1655 case-insensitive file system (such as Mac OS X HFS+). In the build
1656 directory an extension is used, but not in the installed python.
1657
Tim Petersb3c9af12001-11-17 00:21:57 +00001658C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001659-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001660
Tim Petersf582b822001-12-11 18:51:08 +00001661- New function PyDict_MergeFromSeq2() exposes the builtin dict
1662 constructor's logic for updating a dictionary from an iterable object
1663 producing key-value pairs.
1664
Tim Peterscffed4b2001-11-29 03:26:37 +00001665- PyArg_ParseTupleAndKeywords() requires that the number of entries in
Tim Petersf582b822001-12-11 18:51:08 +00001666 the keyword list equal the number of argument specifiers. This
Tim Peterscffed4b2001-11-29 03:26:37 +00001667 wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
1668 dump core in some bad cases. This has been repaired. As a result,
1669 PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
1670 previously went unchallenged.
1671
Tim Petersb3c9af12001-11-17 00:21:57 +00001672New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001673-------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001674
1675Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001676-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001677
1678Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001679-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001680
1681Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001682----
Tim Petersb3c9af12001-11-17 00:21:57 +00001683
Jack Jansenffa260f2001-12-06 21:14:00 +00001684- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
1685 without any trailing digits.
Tim Petersb3c9af12001-11-17 00:21:57 +00001686
Barry Warsaw06557452001-12-14 20:47:12 +00001687- Changed logic for finding python home in Mac OS X framework Pythons.
1688 Now sys.executable points to the executable again, in stead of to
1689 the shared library. The latter is used only for locating the python
1690 home.
1691
1692
Tim Peters84362bc2001-10-19 17:55:30 +00001693What's New in Python 2.2b2?
Tim Peters84362bc2001-10-19 17:55:30 +00001694===========================
1695
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001696*Release date: 16-Nov-2001*
1697
Tim Peters84362bc2001-10-19 17:55:30 +00001698Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001699--------------------------------------------
Tim Peters84362bc2001-10-19 17:55:30 +00001700
Guido van Rossum3d27df02001-11-15 20:27:54 +00001701- Multiple inheritance mixing new-style and classic classes in the
1702 list of base classes is now allowed, so this works now:
Tim Peters76f7fe32001-11-15 20:02:21 +00001703
1704 class Classic: pass
Guido van Rossum3d27df02001-11-15 20:27:54 +00001705 class Mixed(Classic, object): pass
Tim Peters76f7fe32001-11-15 20:02:21 +00001706
1707 The MRO (method resolution order) for each base class is respected
1708 according to its kind, but the MRO for the derived class is computed
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001709 using new-style MRO rules if any base class is a new-style class.
Tim Peters76f7fe32001-11-15 20:02:21 +00001710 This needs to be documented.
1711
Tim Petersa427a2b2001-10-29 22:25:45 +00001712- The new builtin dictionary() constructor, and dictionary type, have
1713 been renamed to dict. This reflects a decade of common usage.
1714
Guido van Rossum3fc08d22001-11-15 20:33:10 +00001715- dict() now accepts an iterable object producing 2-sequences. For
1716 example, dict(d.items()) == d for any dictionary d. The argument,
1717 and the elements of the argument, can be any iterable objects.
1718
Guido van Rossum7ad2d1e2001-10-29 22:11:00 +00001719- New-style classes can now have a __del__ method, which is called
1720 when the instance is deleted (just like for classic classes).
1721
Guido van Rossum12d955c2001-10-26 14:56:06 +00001722- Assignment to object.__dict__ is now possible, for objects that are
1723 instances of new-style classes that have a __dict__ (unless the base
1724 class forbids it).
1725
Guido van Rossumc8e56452001-10-22 00:43:43 +00001726- Methods of built-in types now properly check for keyword arguments
1727 (formerly these were silently ignored). The only built-in methods
1728 that take keyword arguments are __call__, __init__ and __new__.
1729
Guido van Rossum86443212001-10-27 22:28:54 +00001730- The socket function has been converted to a type; see below.
1731
Tim Peters84362bc2001-10-19 17:55:30 +00001732Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001733-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001734
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001735- Assignment to __debug__ raises SyntaxError at compile-time. This
1736 was promised when 2.1c1 was released as "What's New in Python 2.1c1"
Barry Warsaw012852b2001-11-16 16:17:27 +00001737 (see below) says.
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001738
Guido van Rossum12d955c2001-10-26 14:56:06 +00001739- Clarified the error messages for unsupported operands to an operator
1740 (like 1 + '').
1741
Tim Peters84362bc2001-10-19 17:55:30 +00001742Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001743-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001744
Tim Peters5ebfd362001-11-13 23:11:19 +00001745- mmap has a new keyword argument, "access", allowing a uniform way for
1746 both Windows and Unix users to create read-only, write-through and
1747 copy-on-write memory mappings. This was previously possible only on
1748 Unix. A new keyword argument was required to support this in a
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001749 uniform way because the mmap() signatures had diverged across
Tim Peters5ebfd362001-11-13 23:11:19 +00001750 platforms. Thanks to Jay T Miller for repairing this!
1751
Tim Peters169ded02001-11-03 19:57:21 +00001752- By default, the gc.garbage list now contains only those instances in
1753 unreachable cycles that have __del__ methods; in 2.1 it contained all
1754 instances in unreachable cycles. "Instances" here has been generalized
1755 to include instances of both new-style and old-style classes.
1756
Guido van Rossum12d955c2001-10-26 14:56:06 +00001757- The socket module defines a new method for socket objects,
1758 sendall(). This is like send() but may make multiple calls to
Guido van Rossum86443212001-10-27 22:28:54 +00001759 send() until all data has been sent. Also, the socket function has
1760 been converted to a subclassable type, like list and tuple (etc.)
1761 before it; socket and SocketType are now the same thing.
Guido van Rossum12d955c2001-10-26 14:56:06 +00001762
1763- Various bugfixes to the curses module. There is now a test suite
1764 for the curses module (you have to run it manually).
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001765
Guido van Rossum692adf12001-10-30 03:03:03 +00001766- binascii.b2a_base64 no longer places an arbitrary restriction of 57
1767 bytes on its input.
1768
Tim Peters84362bc2001-10-19 17:55:30 +00001769Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001770-------
Tim Peters84362bc2001-10-19 17:55:30 +00001771
Tim Peters5ebfd362001-11-13 23:11:19 +00001772- tkFileDialog exposes a Directory class and askdirectory
Martin v. Löwis25ee87c2001-11-07 22:38:08 +00001773 convenience function.
1774
Tim Peters75335872001-11-03 19:35:43 +00001775- Symbolic group names in regular expressions must be unique. For
1776 example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
1777 single name can't mean both "group 1" and "group 2" simultaneously.
Barry Warsaw012852b2001-11-16 16:17:27 +00001778 Python 2.2 detects this error at regexp compilation time;
1779 previously, the error went undetected, and results were
1780 unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
1781 pattern.subn() methods have been rewritten in C. Also, an
1782 experimental function/method finditer() has been added, which works
1783 like findall() but returns an iterator.
Tim Peters75335872001-11-03 19:35:43 +00001784
Martin v. Löwisb7b32602001-11-02 23:48:20 +00001785- Tix exposes more commands through the classes DirSelectBox,
1786 DirSelectDialog, ListNoteBook, Meter, CheckList, and the
1787 methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
1788 tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
1789
Tim Peters98791af2001-10-23 01:59:54 +00001790- Traceback objects are now scanned by cyclic garbage collection, so
1791 cycles created by casual use of sys.exc_info() no longer cause
1792 permanent memory leaks (provided garbage collection is enabled).
1793
Guido van Rossum49192142001-10-24 20:51:44 +00001794- os.extsep -- a new variable needed by the RISCOS support. It is the
1795 separator used by extensions, and is '.' on all platforms except
1796 RISCOS, where it is '/'. There is no need to use this variable
1797 unless you have a masochistic desire to port your code to RISCOS.
1798
Barry Warsaw012852b2001-11-16 16:17:27 +00001799- mimetypes.py has optional support for non-standard, but commonly
1800 found types. guess_type() and guess_extension() now accept an
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001801 optional 'strict' flag, defaulting to true, which controls whether
Barry Warsaw012852b2001-11-16 16:17:27 +00001802 recognize non-standard types or not. A few non-standard types we
1803 know about have been added. Also, when run as a script, there are
1804 new -l and -e options.
1805
1806- statcache is now deprecated.
1807
1808- email.Utils.formatdate() now produces the preferred RFC 2822 style
1809 dates with numeric timezones (it used to produce obsolete dates
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001810 hard coded to "GMT" timezone). An optional 'localtime' flag is
Barry Warsaw012852b2001-11-16 16:17:27 +00001811 added to produce dates in the local timezone, with daylight savings
1812 time properly taken into account.
1813
1814- In pickle and cPickle, instead of masking errors in load() by
1815 transforming them into SystemError, we let the original exception
1816 propagate out. Also, implement support for __safe_for_unpickling__
1817 in pickle, as it already was supported in cPickle.
1818
Tim Peters84362bc2001-10-19 17:55:30 +00001819Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001820-----------
Tim Peters84362bc2001-10-19 17:55:30 +00001821
1822Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001823-----
Tim Peters84362bc2001-10-19 17:55:30 +00001824
Barry Warsaw012852b2001-11-16 16:17:27 +00001825- The dbm module is built using libdb1 if available. The bsddb module
1826 is built with libdb3 if available.
1827
1828- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
1829
Tim Peters84362bc2001-10-19 17:55:30 +00001830C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001831-----
Tim Peters84362bc2001-10-19 17:55:30 +00001832
Tim Peters1fc240e2001-10-26 05:06:50 +00001833- New function PySequence_Fast_GET_SIZE() returns the size of a non-
1834 NULL result from PySequence_Fast(), more quickly than calling
1835 PySequence_Size().
1836
Barry Warsaw012852b2001-11-16 16:17:27 +00001837- New argument unpacking function PyArg_UnpackTuple() added.
1838
1839- New functions PyObject_CallFunctionObjArgs() and
1840 PyObject_CallMethodObjArgs() have been added to make it more
1841 convenient and efficient to call functions and methods from C.
1842
1843- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
1844 possible that this will propagate errors it didn't before.
1845
1846- New function PyObject_CheckReadBuffer(), which returns true if its
1847 argument supports the single-segment readable buffer interface.
1848
Tim Peters84362bc2001-10-19 17:55:30 +00001849New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001850-------------
Tim Peters84362bc2001-10-19 17:55:30 +00001851
Guido van Rossum86443212001-10-27 22:28:54 +00001852- We've finally confirmed that this release builds on HP-UX 11.00,
1853 *with* threads, and passes the test suite.
1854
Tim Peters7a33d8b2001-11-05 02:51:07 +00001855- Thanks to a series of patches from Michael Muller, Python may build
1856 again under OS/2 Visual Age C++.
1857
Guido van Rossum49192142001-10-24 20:51:44 +00001858- Updated RISCOS port by Dietmar Schwertberger.
1859
Tim Peters84362bc2001-10-19 17:55:30 +00001860Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001861-----
Tim Peters84362bc2001-10-19 17:55:30 +00001862
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001863- Added a test script for the curses module. It isn't run automatically;
1864 regrtest.py must be run with '-u curses' to enable it.
1865
Tim Peters84362bc2001-10-19 17:55:30 +00001866Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001867-------
Tim Peters84362bc2001-10-19 17:55:30 +00001868
Barry Warsaw012852b2001-11-16 16:17:27 +00001869Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001870----
Barry Warsaw012852b2001-11-16 16:17:27 +00001871
1872- PythonScript has been moved to unsupported and is slated to be
1873 removed completely in the next release.
1874
1875- It should now be possible to build applets that work on both OS9 and
1876 OSX.
1877
1878- The core is now linked with CoreServices not Carbon; as a side
1879 result, default 8bit encoding on OSX is now ASCII.
1880
1881- Python should now build on OSX 10.1.1
1882
Tim Peters84362bc2001-10-19 17:55:30 +00001883
Tim Petersabf925f2001-09-28 21:53:42 +00001884What's New in Python 2.2b1?
Tim Petersabf925f2001-09-28 21:53:42 +00001885===========================
1886
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001887*Release date: 19-Oct-2001*
1888
Tim Petersabf925f2001-09-28 21:53:42 +00001889Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001890--------------------------------------------
Tim Petersabf925f2001-09-28 21:53:42 +00001891
Guido van Rossum687ae002001-10-15 22:03:32 +00001892- New-style classes are now always dynamic (except for built-in and
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001893 extension types). There is no longer a performance penalty, and I
Guido van Rossum687ae002001-10-15 22:03:32 +00001894 no longer see another reason to keep this baggage around. One relic
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001895 remains: the __dict__ of a new-style class is a read-only proxy; you
1896 must set the class's attribute to modify it. As a consequence, the
Guido van Rossum687ae002001-10-15 22:03:32 +00001897 __defined__ attribute of new-style types no longer exists, for lack
1898 of need: there is once again only one __dict__ (although in the
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001899 future a __cache__ may be resurrected with a similar function, if I
1900 can prove that it actually speeds things up).
Guido van Rossum50fda3b2001-10-04 19:46:06 +00001901
Tim Peters1c9ca872001-10-04 06:43:12 +00001902- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
1903 always returned None, even when there was a class docstring).
1904
1905- doctest now finds and runs docstrings attached to new-style classes,
1906 class methods, static methods, and properties.
1907
Guido van Rossum9074ef62001-10-16 21:34:49 +00001908Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001909-----------------
Tim Petersabf925f2001-09-28 21:53:42 +00001910
Guido van Rossuma8bcf802001-10-15 15:53:58 +00001911- A very subtle syntactical pitfall in list comprehensions was fixed.
1912 For example: [a+b for a in 'abc', for b in 'def']. The comma in
1913 this example is a mistake. Previously, this would silently let 'a'
1914 iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
1915 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
1916 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
1917 Note that [a for a in <singleton>] is a convoluted way to say
1918 [<singleton>] anyway, so it's not like any expressiveness is lost.
1919
Guido van Rossum9074ef62001-10-16 21:34:49 +00001920- getattr(obj, name, default) now only catches AttributeError, as
1921 documented, rather than returning the default value for all
1922 exceptions (which could mask bugs in a __getattr__ hook, for
1923 example).
1924
Fred Drakecb7a6b52001-10-22 18:41:51 +00001925- Weak reference objects are now part of the core and offer a C API.
Fred Drake934d2a42001-10-18 18:18:06 +00001926 A bug which could allow a core dump when binary operations involved
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001927 proxy reference has been fixed. weakref.ReferenceError is now a
Barry Warsawf6fb1712001-10-19 05:35:40 +00001928 built-in exception.
Fred Drake934d2a42001-10-18 18:18:06 +00001929
Guido van Rossum1c486092001-10-19 02:05:35 +00001930- unicode(obj) now behaves more like str(obj), accepting arbitrary
1931 objects, and calling a __unicode__ method if it exists.
1932 unicode(obj, encoding) and unicode(obj, encoding, errors) still
Marc-André Lemburgb5507ec2001-10-19 12:02:29 +00001933 require an 8-bit string or character buffer argument.
Guido van Rossum1c486092001-10-19 02:05:35 +00001934
Barry Warsawf6fb1712001-10-19 05:35:40 +00001935- isinstance() now allows any object as the first argument and a
1936 class, a type or something with a __bases__ tuple attribute for the
1937 second argument. The second argument may also be a tuple of a
1938 class, type, or something with __bases__, in which case isinstance()
1939 will return true if the first argument is an instance of any of the
1940 things contained in the second argument tuple. E.g.
1941
1942 isinstance(x, (A, B))
1943
1944 returns true if x is an instance of A or B.
1945
Guido van Rossum9074ef62001-10-16 21:34:49 +00001946Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001947-----------------
Guido van Rossum9074ef62001-10-16 21:34:49 +00001948
1949- thread.start_new_thread() now returns the thread ID (previously None).
1950
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001951- binascii has now two quopri support functions, a2b_qp and b2a_qp.
1952
Guido van Rossumc524d952001-10-19 01:31:59 +00001953- readline now supports setting the startup_hook and the
1954 pre_event_hook, and adds the add_history() function.
Martin v. Löwis0daad592001-09-30 21:09:59 +00001955
Guido van Rossumc524d952001-10-19 01:31:59 +00001956- os and posix supports chroot(), setgroups() and unsetenv() where
1957 available. The stat(), fstat(), statvfs() and fstatvfs() functions
1958 now return "pseudo-sequences" -- the various fields can now be
1959 accessed as attributes (e.g. os.stat("/").st_mtime) but for
1960 backwards compatibility they also behave as a fixed-length sequence.
1961 Some platform-specific fields (e.g. st_rdev) are only accessible as
Guido van Rossum98bf58f2001-10-18 20:34:25 +00001962 attributes.
1963
1964- time: localtime(), gmtime() and strptime() now return a
1965 pseudo-sequence similar to the os.stat() return value, with
1966 attributes like tm_year etc.
Martin v. Löwis16628c92001-10-04 22:46:41 +00001967
Guido van Rossum9074ef62001-10-16 21:34:49 +00001968- Decompression objects in the zlib module now accept an optional
1969 second parameter to decompress() that specifies the maximum amount
1970 of memory to use for the uncompressed data.
Tim Petersabf925f2001-09-28 21:53:42 +00001971
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001972- optional SSL support in the socket module now exports OpenSSL
1973 functions RAND_add(), RAND_egd(), and RAND_status(). These calls
1974 are useful on platforms like Solaris where OpenSSL does not
Barry Warsawf6fb1712001-10-19 05:35:40 +00001975 automatically seed its PRNG. Also, the keyfile and certfile
1976 arguments to socket.ssl() are now optional.
1977
1978- posixmodule (and by extension, the os module on POSIX platforms) now
1979 exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001980
Guido van Rossum9074ef62001-10-16 21:34:49 +00001981Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001982-------
Guido van Rossum3c288632001-10-16 21:13:49 +00001983
Tim Peters7402f792001-10-02 03:53:41 +00001984- doctest now excludes functions and classes not defined by the module
1985 being tested, thanks to Tim Hochberg.
1986
Fred Drakecb7a6b52001-10-22 18:41:51 +00001987- HotShot, a new profiler implemented using a C-based callback, has
1988 been added. This substantially reduces the overhead of profiling,
1989 but it is still quite preliminary. Support modules and
1990 documentation will be added in upcoming releases (before 2.2 final).
1991
Guido van Rossumc4b09b42001-10-04 10:19:00 +00001992- profile now produces correct output in situations where an exception
1993 raised in Python is cleared by C code (e.g. hasattr()). This used
1994 to cause wrong output, including spurious claims of recursive
1995 functions and attribution of time spent to the wrong function.
1996
Tim Peters0a1fc4e2001-10-07 03:12:08 +00001997 The code and documentation for the derived OldProfile and HotProfile
1998 profiling classes was removed. The code hasn't worked for years (if
1999 you tried to use them, they raised exceptions). OldProfile
2000 intended to reproduce the behavior of the profiler Python used more
2001 than 7 years ago, and isn't interesting anymore. HotProfile intended
2002 to provide a faster profiler (but producing less information), and
2003 that's a worthy goal we intend to meet via a different approach (but
2004 without losing information).
2005
Tim Peterscce092d2001-10-09 05:31:56 +00002006- Profile.calibrate() has a new implementation that should deliver
Tim Peters659a6032001-10-09 20:51:19 +00002007 a much better system-specific calibration constant. The constant can
2008 now be specified in an instance constructor, or as a Profile class or
2009 instance variable, instead of by editing profile.py's source code.
2010 Calibration must still be done manually (see the docs for the profile
2011 module).
2012
2013 Note that Profile.calibrate() must be overriden by subclasses.
2014 Improving the accuracy required exploiting detailed knowledge of
2015 profiler internals; the earlier method abstracted away the details
2016 and measured a simplified model instead, but consequently computed
2017 a constant too small by a factor of 2 on some modern machines.
Tim Peterscce092d2001-10-09 05:31:56 +00002018
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00002019- quopri's encode and decode methods take an optional header parameter,
Jeremy Hylton6f543b62001-10-16 20:42:52 +00002020 which indicates whether output is intended for the header 'Q'
2021 encoding.
2022
Guido van Rossuma5343cc2001-10-18 18:02:07 +00002023- The SocketServer.ThreadingMixIn class now closes the request after
2024 finish_request() returns. (Not when it errors out though.)
2025
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002026- The nntplib module's NNTP.body() method has grown a 'file' argument
Barry Warsawf6fb1712001-10-19 05:35:40 +00002027 to allow saving the message body to a file.
2028
2029- The email package has added a class email.Parser.HeaderParser which
2030 only parses headers and does not recurse into the message's body.
2031 Also, the module/class MIMEAudio has been added for representing
2032 audio data (contributed by Anthony Baxter).
2033
2034- ftplib should be able to handle files > 2GB.
2035
2036- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
2037 ON, and OFF.
2038
Fred Drakecb7a6b52001-10-22 18:41:51 +00002039- xml.dom.minidom NodeList objects now support the length attribute
2040 and item() method as required by the DOM specifications.
2041
Guido van Rossumed554f62001-10-02 23:15:37 +00002042Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002043-----------
Guido van Rossumed554f62001-10-02 23:15:37 +00002044
2045- Demo/dns was removed. It no longer serves any purpose; a package
2046 derived from it is now maintained by Anthony Baxter, see
2047 http://PyDNS.SourceForge.net.
Tim Petersabf925f2001-09-28 21:53:42 +00002048
Barry Warsawf6fb1712001-10-19 05:35:40 +00002049- The freeze tool has been made more robust, and two new options have
2050 been added: -X and -E.
2051
Tim Petersabf925f2001-09-28 21:53:42 +00002052Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002053-----
Tim Petersabf925f2001-09-28 21:53:42 +00002054
Barry Warsawf6fb1712001-10-19 05:35:40 +00002055- configure will use CXX in LINKCC if CXX is used to build main() and
2056 the system requires to link a C++ main using the C++ compiler.
2057
Tim Petersabf925f2001-09-28 21:53:42 +00002058C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002059-----
Tim Petersabf925f2001-09-28 21:53:42 +00002060
Guido van Rossum6c4bce32001-10-18 19:20:25 +00002061- The documentation for the tp_compare slot is updated to require that
2062 the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
2063 not correct. This is not yet enforced but will be enforced in
2064 Python 2.3; even later, we may use -2 to indicate errors and +2 for
2065 "NotImplemented". Right now, -1 should be used for an error return.
2066
Tim Petersd38b1c72001-09-30 05:09:37 +00002067- PyLong_AsLongLong() now accepts int (as well as long) arguments.
2068 Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
2069 as long) arguments.
2070
Guido van Rossum3c288632001-10-16 21:13:49 +00002071- PyThread_start_new_thread() now returns a long int giving the thread
2072 ID, if one can be calculated; it returns -1 for error, 0 if no
2073 thread ID is calculated (this is an incompatible change, but only
2074 the thread module used this API). This code has only really been
2075 tested on Linux and Windows; other platforms please beware (and
2076 report any bugs or strange behavior).
2077
Guido van Rossum1c486092001-10-19 02:05:35 +00002078- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
2079 input.
2080
Tim Petersabf925f2001-09-28 21:53:42 +00002081New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002082-------------
Tim Petersabf925f2001-09-28 21:53:42 +00002083
2084Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002085-----
Tim Petersabf925f2001-09-28 21:53:42 +00002086
2087Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002088-------
Tim Petersabf925f2001-09-28 21:53:42 +00002089
Tim Peters04cf1d32001-10-09 22:39:40 +00002090- Installer: If you install IDLE, and don't disable file-extension
2091 registration, a new "Edit with IDLE" context (right-click) menu entry
2092 is created for .py and .pyw files.
2093
Tim Peters1ce3cf72001-10-01 17:58:40 +00002094- The signal module now supports SIGBREAK on Windows, thanks to Steven
2095 Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
2096 action remains to call Win32 ExitProcess(). This can be changed via
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002097 signal.signal(). For example::
Tim Peters1ce3cf72001-10-01 17:58:40 +00002098
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002099 # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
2100 # (SIGINT) behavior.
2101 import signal
2102 signal.signal(signal.SIGBREAK, signal.default_int_handler)
Tim Peters1ce3cf72001-10-01 17:58:40 +00002103
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002104 try:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002105 while 1:
2106 pass
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002107 except KeyboardInterrupt:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002108 # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
2109 # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
2110 # program without the possibility for any Python-level cleanup).
2111 print "Clean exit"
Tim Peters1ce3cf72001-10-01 17:58:40 +00002112
Tim Petersabf925f2001-09-28 21:53:42 +00002113
Tim Petersb07352e2001-09-08 01:25:47 +00002114What's New in Python 2.2a4?
2115===========================
2116
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002117*Release date: 28-Sep-2001*
2118
Guido van Rossum808eea72001-09-25 04:15:41 +00002119Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002120--------------------------------------------
Guido van Rossum808eea72001-09-25 04:15:41 +00002121
2122- pydoc and inspect are now aware of new-style classes;
2123 e.g. help(list) at the interactive prompt now shows proper
2124 documentation for all operations on list objects.
2125
2126- Applications using Jim Fulton's ExtensionClass module can now safely
2127 be used with Python 2.2. In particular, Zope 2.4.1 now works with
2128 Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
2129 examples also work again. It is hoped that Gtk and Boost also work
2130 with 2.2a4 and beyond. (If you can confirm this, please write
2131 webmaster@python.org; if there are still problems, please open a bug
2132 report on SourceForge.)
Tim Petersb07352e2001-09-08 01:25:47 +00002133
Tim Peters66c1a522001-09-24 21:17:50 +00002134- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00002135 These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
Tim Peters66c1a522001-09-24 21:17:50 +00002136 in the constructed property object. fget, fset and fdel weren't
2137 discoverable from Python in 2.2a3. __doc__ is new, and allows to
2138 associate a docstring with a property.
2139
Guido van Rossum808eea72001-09-25 04:15:41 +00002140- Comparison overloading is now more completely implemented. For
2141 example, a str subclass instance can properly be compared to a str
2142 instance, and it can properly overload comparison. Ditto for most
2143 other built-in object types.
2144
2145- The repr() of new-style classes has changed; instead of <type
2146 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
2147 *except* for built-in types, which are still rendered as <type
2148 'Foo'> (to avoid upsetting existing code that might parse or
2149 otherwise rely on repr() of certain type objects).
2150
2151- The repr() of new-style objects is now always <Foo object at XXX>;
2152 previously, it was sometimes <Foo instance at XXX>.
2153
2154- For new-style classes, what was previously called __getattr__ is now
2155 called __getattribute__. This method, if defined, is called for
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00002156 *every* attribute access. A new __getattr__ hook more similar to the
Guido van Rossum808eea72001-09-25 04:15:41 +00002157 one in classic classes is defined which is called only if regular
2158 attribute access raises AttributeError; to catch *all* attribute
2159 access, you can use __getattribute__ (for new-style classes). If
2160 both are defined, __getattribute__ is called first, and if it raises
2161 AttributeError, __getattr__ is called.
2162
2163- The __class__ attribute of new-style objects can be assigned to.
2164 The new class must have the same C-level object layout as the old
2165 class.
2166
2167- The builtin file type can be subclassed now. In the usual pattern,
2168 "file" is the name of the builtin type, and file() is a new builtin
2169 constructor, with the same signature as the builtin open() function.
2170 file() is now the preferred way to open a file.
2171
2172- Previously, __new__ would only see sequential arguments passed to
2173 the type in a constructor call; __init__ would see both sequential
2174 and keyword arguments. This made no sense whatsoever any more, so
2175 now both __new__ and __init__ see all arguments.
2176
2177- Previously, hash() applied to an instance of a subclass of str or
2178 unicode always returned 0. This has been repaired.
2179
2180- Previously, an operation on an instance of a subclass of an
2181 immutable type (int, long, float, complex, tuple, str, unicode),
2182 where the subtype didn't override the operation (and so the
2183 operation was handled by the builtin type), could return that
2184 instance instead a value of the base type. For example, if s was of
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00002185 a str subclass type, s[:] returned s as-is. Now it returns a str
Guido van Rossum808eea72001-09-25 04:15:41 +00002186 with the same value as s.
2187
Barry Warsaw86fbaf82001-09-28 15:26:12 +00002188- Provisional support for pickling new-style objects has been added.
2189
Guido van Rossum808eea72001-09-25 04:15:41 +00002190Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002191----
Guido van Rossum808eea72001-09-25 04:15:41 +00002192
Tim Peters2c9aa5e2001-09-23 04:06:05 +00002193- file.writelines() now accepts any iterable object producing strings.
2194
Marc-André Lemburgaefd7662001-09-20 12:59:37 +00002195- PyUnicode_FromEncodedObject() now works very much like
2196 PyObject_Str(obj) in that it tries to use __str__/tp_str
2197 on the object if the object is not a string or buffer. This
2198 makes unicode() behave like str() when applied to non-string/buffer
2199 objects.
2200
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00002201- PyFile_WriteObject now passes Unicode objects to the file's write
2202 method. As a result, all file-like objects which may be the target
Martin v. Löwis2777c022001-09-19 13:47:32 +00002203 of a print statement must support Unicode objects, i.e. they must
2204 at least convert them into ASCII strings.
2205
Guido van Rossum624c8af2001-09-18 15:21:04 +00002206- Thread scheduling on Solaris should be improved; it is no longer
2207 necessary to insert a small sleep at the start of a thread in order
2208 to let other runnable threads be scheduled.
2209
Tim Petersb07352e2001-09-08 01:25:47 +00002210Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002211-------
Tim Petersb07352e2001-09-08 01:25:47 +00002212
Marc-André Lemburgbf990172001-09-27 14:17:33 +00002213- StringIO.StringIO instances and cStringIO.StringIO instances support
2214 read character buffer compatible objects for their .write() methods.
2215 These objects are converted to strings and then handled as such
2216 by the instances.
2217
Barry Warsaw2f600732001-09-24 04:28:10 +00002218- The "email" package has been added. This is basically a port of the
2219 mimelib package <http://sf.net/projects/mimelib> with API changes
2220 and some implementations updated to use iterators and generators.
2221
Tim Peters8a9c2842001-09-22 21:30:22 +00002222- difflib.ndiff() and difflib.Differ.compare() are generators now. This
2223 restores the ability of Tools/scripts/ndiff.py to start producing output
2224 before the entire comparison is complete.
2225
Barry Warsaw58b072d2001-09-22 04:44:21 +00002226- StringIO.StringIO instances and cStringIO.StringIO instances support
2227 iteration just like file objects (i.e. their .readline() method is
2228 called for each iteration until it returns an empty string).
2229
Marc-André Lemburg494f2ae2001-09-19 11:33:31 +00002230- The codecs module has grown four new helper APIs to access
2231 builtin codecs: getencoder(), getdecoder(), getreader(),
2232 getwriter().
2233
Guido van Rossum624c8af2001-09-18 15:21:04 +00002234- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
2235 simplifies writing XML RPC servers.
2236
Barry Warsaw647d5e82001-09-28 17:01:02 +00002237- os.path.realpath(): a new function that returns the absolute pathname
Guido van Rossum624c8af2001-09-18 15:21:04 +00002238 after interpretation of symbolic links. On non-Unix systems, this
2239 is an alias for os.path.abspath().
2240
Tim Peters16a77ad2001-09-08 04:00:12 +00002241- operator.indexOf() (PySequence_Index() in the C API) now works with any
2242 iterable object.
2243
Guido van Rossum624c8af2001-09-18 15:21:04 +00002244- smtplib now supports various authentication and security features of
2245 the SMTP protocol through the new login() and starttls() methods.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00002246
Guido van Rossum624c8af2001-09-18 15:21:04 +00002247- hmac: a new module implementing keyed hashing for message
2248 authentication.
2249
2250- mimetypes now recognizes more extensions and file types. At the
2251 same time, some mappings not sanctioned by IANA were removed.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00002252
Guido van Rossum624c8af2001-09-18 15:21:04 +00002253- The "compiler" package has been brought up to date to the state of
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00002254 Python 2.2 bytecode generation. It has also been promoted from a
2255 Tool to a standard library package. (Tools/compiler still exists as
2256 a sample driver.)
2257
Tim Petersb07352e2001-09-08 01:25:47 +00002258Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002259-----
Tim Petersb07352e2001-09-08 01:25:47 +00002260
Guido van Rossum624c8af2001-09-18 15:21:04 +00002261- Large file support (LFS) is now automatic when the platform supports
2262 it; no more manual configuration tweaks are needed. On Linux, at
2263 least, it's possible to have a system whose C library supports large
2264 files but whose kernel doesn't; in this case, large file support is
2265 still enabled but doesn't do you any good unless you upgrade your
2266 kernel or share your Python executable with another system whose
2267 kernel has large file support.
2268
2269- The configure script now supplies plausible defaults in a
2270 cross-compilation environment. This doesn't mean that the supplied
2271 values are always correct, or that cross-compilation now works
2272 flawlessly -- but it's a first step (and it shuts up most of
2273 autoconf's warnings about AC_TRY_RUN).
2274
2275- The Unix build is now a bit less chatty, courtesy of the parser
2276 generator. The build is completely silent (except for errors) when
2277 using "make -s", thanks to a -q option to setup.py.
2278
Tim Petersb07352e2001-09-08 01:25:47 +00002279C API
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- The "structmember" API now supports some new flag bits to deny read
2283 and/or write access to attributes in restricted execution mode.
2284
Tim Petersb07352e2001-09-08 01:25:47 +00002285New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002286-------------
Tim Petersb07352e2001-09-08 01:25:47 +00002287
Guido van Rossum624c8af2001-09-18 15:21:04 +00002288- Compaq's iPAQ handheld, running the "familiar" Linux distribution
2289 (http://familiar.handhelds.org).
2290
Tim Petersb07352e2001-09-08 01:25:47 +00002291Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002292-----
Tim Petersb07352e2001-09-08 01:25:47 +00002293
Tim Peters8a9c2842001-09-22 21:30:22 +00002294- The "classic" standard tests, which work by comparing stdout to
2295 an expected-output file under Lib/test/output/, no longer stop at
2296 the first mismatch. Instead the test is run to completion, and a
2297 variant of ndiff-style comparison is used to report all differences.
2298 This is much easier to understand than the previous style of reporting.
2299
2300- The unittest-based standard tests now use regrtest's test_main()
2301 convention, instead of running as a side-effect of merely being
2302 imported. This allows these tests to be run in more natural and
2303 flexible ways as unittests, outside the regrtest framework.
2304
2305- regrtest.py is much better integrated with unittest and doctest now,
2306 especially in regard to reporting errors.
2307
Tim Petersb07352e2001-09-08 01:25:47 +00002308Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002309-------
Tim Petersb07352e2001-09-08 01:25:47 +00002310
Guido van Rossum624c8af2001-09-18 15:21:04 +00002311- Large file support now also works for files > 4GB, on filesystems
Tim Peters8a9c2842001-09-22 21:30:22 +00002312 that support it (NTFS under Windows 2000). See "What's New in
2313 Python 2.2a3" for more detail.
Guido van Rossum624c8af2001-09-18 15:21:04 +00002314
Tim Petersb07352e2001-09-08 01:25:47 +00002315
Tim Petersedc99312001-08-22 21:36:50 +00002316What's New in Python 2.2a3?
2317===========================
2318
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002319*Release Date: 07-Sep-2001*
2320
Tim Petersedc99312001-08-22 21:36:50 +00002321Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002322----
Tim Petersedc99312001-08-22 21:36:50 +00002323
Tim Peters9fffa3e2001-09-04 05:14:19 +00002324- Conversion of long to float now raises OverflowError if the long is too
2325 big to represent as a C double.
2326
Tim Peters32f453e2001-09-03 08:35:41 +00002327- The 3-argument builtin pow() no longer allows a third non-None argument
2328 if either of the first two arguments is a float, or if both are of
2329 integer types and the second argument is negative (in which latter case
2330 the arguments are converted to float, so this is really the same
2331 restriction).
2332
Tim Peters5d2b77c2001-09-03 05:47:38 +00002333- The builtin dir() now returns more information, and sometimes much
2334 more, generally naming all attributes of an object, and all attributes
2335 reachable from the object via its class, and from its class's base
2336 classes, and so on from them too. Example: in 2.2a2, dir([]) returned
2337 an empty list. In 2.2a3,
2338
2339 >>> dir([])
2340 ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
2341 '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
2342 '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
2343 '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
2344 '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
2345 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
2346 'reverse', 'sort']
2347
2348 dir(module) continues to return only the module's attributes, though.
2349
Tim Petersbdee63f2001-09-02 03:40:59 +00002350- Overflowing operations on plain ints now return a long int rather
Guido van Rossumae457142001-08-31 18:31:35 +00002351 than raising OverflowError. This is a partial implementation of PEP
2352 237. You can use -Wdefault::OverflowWarning to enable a warning for
2353 this situation, and -Werror::OverflowWarning to revert to the old
2354 OverflowError exception.
2355
Guido van Rossum61c345f2001-09-04 03:26:15 +00002356- A new command line option, -Q<arg>, is added to control run-time
Guido van Rossumae457142001-08-31 18:31:35 +00002357 warnings for the use of classic division. (See PEP 238.) Possible
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002358 values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
2359 -Qold, meaning the / operator has its classic meaning and no
2360 warnings are issued. Using -Qwarn issues a run-time warning about
2361 all uses of classic division for int and long arguments; -Qwarnall
2362 also warns about classic division for float and complex arguments
Tim Peters3caca232001-12-06 06:23:26 +00002363 (for use with fixdiv.py).
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002364 [Note: the remainder of this item (preserved below) became
2365 obsolete in 2.2c1 -- -Qnew has global effect in 2.2] ::
2366
2367 Using -Qnew is questionable; it turns on new division by default, but
2368 only in the __main__ module. You can usefully combine -Qwarn or
2369 -Qwarnall and -Qnew: this gives the __main__ module new division, and
2370 warns about classic division everywhere else.
Guido van Rossumae457142001-08-31 18:31:35 +00002371
Tim Petersbdee63f2001-09-02 03:40:59 +00002372- Many built-in types can now be subclassed. This applies to int,
Guido van Rossumae457142001-08-31 18:31:35 +00002373 long, float, str, unicode, and tuple. (The types complex, list and
2374 dictionary can also be subclassed; this was introduced earlier.)
2375 Note that restrictions apply when subclassing immutable built-in
2376 types: you can only affect the value of the instance by overloading
2377 __new__. You can add mutable attributes, and the subclass instances
2378 will have a __dict__ attribute, but you cannot change the "value"
2379 (as implemented by the base class) of an immutable subclass instance
2380 once it is created.
2381
Guido van Rossumaaf80c82001-09-02 13:44:35 +00002382- The dictionary constructor now takes an optional argument, a
2383 mapping-like object, and initializes the dictionary from its
2384 (key, value) pairs.
2385
Tim Petersbdee63f2001-09-02 03:40:59 +00002386- A new built-in type, super, has been added. This facilitates making
Guido van Rossumae457142001-08-31 18:31:35 +00002387 "cooperative super calls" in a multiple inheritance setting. For an
2388 explanation, see http://www.python.org/2.2/descrintro.html#cooperation
2389
Guido van Rossum8d7234d2001-09-06 22:02:58 +00002390- A new built-in type, property, has been added. This enables the
2391 creation of "properties". These are attributes implemented by
2392 getter and setter functions (or only one of these for read-only or
2393 write-only attributes), without the need to override __getattr__.
2394 See http://www.python.org/2.2/descrintro.html#property
Guido van Rossumae457142001-08-31 18:31:35 +00002395
Tim Petersbdee63f2001-09-02 03:40:59 +00002396- The syntax of floating-point and imaginary literals has been
Tim Petersd507dab2001-08-30 20:51:59 +00002397 liberalized, to allow leading zeroes. Examples of literals now
2398 legal that were SyntaxErrors before:
2399
2400 00.0 0e3 0100j 07.5 00000000000000000008.
2401
Tim Petersbdee63f2001-09-02 03:40:59 +00002402- An old tokenizer bug allowed floating point literals with an incomplete
Tim Petersc6d95812001-08-28 20:56:27 +00002403 exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
2404
Tim Petersedc99312001-08-22 21:36:50 +00002405Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002406-------
Tim Petersedc99312001-08-22 21:36:50 +00002407
Martin v. Löwiscb227c92001-09-06 08:54:16 +00002408- telnetlib includes symbolic names for the options, and support for
Martin v. Löwis1da9c572002-11-04 09:56:00 +00002409 setting an option negotiation callback. It also supports processing
2410 of suboptions.
Martin v. Löwiscb227c92001-09-06 08:54:16 +00002411
Tim Petersa40c7932001-09-05 22:36:56 +00002412- The new C standard no longer requires that math libraries set errno to
2413 ERANGE on overflow. For platform libraries that exploit this new
2414 freedom, Python's overflow-checking was wholly broken. A new overflow-
2415 checking scheme attempts to repair that, but may not be reliable on all
2416 platforms (C doesn't seem to provide anything both useful and portable
2417 in this area anymore).
2418
Martin v. Löwis44f86962001-09-05 13:44:54 +00002419- Asynchronous timeout actions are available through the new class
2420 threading.Timer.
2421
Tim Peters78526162001-09-05 00:53:45 +00002422- math.log and math.log10 now return sensible results for even huge
2423 long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
2424
Tim Petersbdee63f2001-09-02 03:40:59 +00002425- A new function, imp.lock_held(), returns 1 when the import lock is
Tim Peters69232342001-08-30 05:16:13 +00002426 currently held. See the docs for the imp module.
2427
Tim Petersbdee63f2001-09-02 03:40:59 +00002428- pickle, cPickle and marshal on 32-bit platforms can now correctly read
Tim Peters82112372001-08-29 02:28:42 +00002429 dumps containing ints written on platforms where Python ints are 8 bytes.
2430 When read on a box where Python ints are 4 bytes, such values are
2431 converted to Python longs.
2432
Tim Petersbdee63f2001-09-02 03:40:59 +00002433- In restricted execution mode (using the rexec module), unmarshalling
Guido van Rossumae457142001-08-31 18:31:35 +00002434 code objects is no longer allowed. This plugs a security hole.
2435
Steve Purcell6091cd62001-09-06 16:05:17 +00002436- unittest.TestResult instances no longer store references to tracebacks
2437 generated by test failures. This prevents unexpected dangling references
2438 to objects that should be garbage collected between tests.
2439
Tim Petersedc99312001-08-22 21:36:50 +00002440Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002441-----
Tim Petersedc99312001-08-22 21:36:50 +00002442
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002443- Tools/scripts/fixdiv.py has been added which can be used to fix
2444 division operators as per PEP 238.
2445
Tim Petersedc99312001-08-22 21:36:50 +00002446Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002447-----
Tim Petersedc99312001-08-22 21:36:50 +00002448
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002449- If you are an adventurous person using Mac OS X you may want to look at
2450 Mac/OSX. There is a Makefile there that will build Python as a real Mac
2451 application, which can be used for experimenting with Carbon or Cocoa.
2452 Discussion of this on pythonmac-sig, please.
2453
Tim Peters7eea37e2001-09-04 22:08:56 +00002454C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002455-----
Tim Peters7eea37e2001-09-04 22:08:56 +00002456
2457- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
Tim Peters69232342001-08-30 05:16:13 +00002458
Tim Peters9fffa3e2001-09-04 05:14:19 +00002459- Note that PyLong_AsDouble can fail! This has always been true, but no
2460 callers checked for it. It's more likely to fail now, because overflow
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002461 errors are properly detected now. The proper way to check::
Tim Peters9fffa3e2001-09-04 05:14:19 +00002462
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002463 double x = PyLong_AsDouble(some_long_object);
2464 if (x == -1.0 && PyErr_Occurred()) {
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002465 /* The conversion failed. */
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002466 }
Tim Peters9fffa3e2001-09-04 05:14:19 +00002467
Tim Petersbdee63f2001-09-02 03:40:59 +00002468- The GC API has been changed. Extensions that use the old API will still
Neil Schemenauer4042c692001-08-30 15:38:01 +00002469 compile but will not participate in GC. To upgrade an extension
2470 module:
2471
2472 - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
Tim Petersd507dab2001-08-30 20:51:59 +00002473
Neil Schemenauer4042c692001-08-30 15:38:01 +00002474 - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
2475 PyObject_GC_Del to deallocate them
Tim Petersd507dab2001-08-30 20:51:59 +00002476
Neil Schemenauer4042c692001-08-30 15:38:01 +00002477 - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
2478 to PyObject_GC_UnTrack
Tim Petersd507dab2001-08-30 20:51:59 +00002479
Neil Schemenauer4042c692001-08-30 15:38:01 +00002480 - remove PyGC_HEAD_SIZE from object size calculations
2481
2482 - remove calls to PyObject_AS_GC and PyObject_FROM_GC
2483
Tim Petersbdee63f2001-09-02 03:40:59 +00002484- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
Guido van Rossumae457142001-08-31 18:31:35 +00002485 These can be used safely to construct string objects from a
2486 sprintf-style format string (similar to the format string supported
2487 by PyErr_Format()).
Tim Peters69232342001-08-30 05:16:13 +00002488
Tim Petersedc99312001-08-22 21:36:50 +00002489New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002490-------------
Tim Petersedc99312001-08-22 21:36:50 +00002491
Tim Petersb7da0902001-09-02 23:01:43 +00002492- Stephen Hansen contributed patches sufficient to get a clean compile
2493 under Borland C (Windows), but he reports problems running it and ran
2494 out of time to complete the port. Volunteers? Expect a MemoryError
2495 when importing the types module; this is probably shallow, and
2496 causing later failures too.
Tim Petersbdee63f2001-09-02 03:40:59 +00002497
Tim Petersedc99312001-08-22 21:36:50 +00002498Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002499-----
Tim Petersedc99312001-08-22 21:36:50 +00002500
2501Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002502-------
Tim Petersedc99312001-08-22 21:36:50 +00002503
Tim Peters6e13a562001-09-06 00:32:15 +00002504- Large file support is now enabled on Win32 platforms as well as on
2505 Win64. This means that, for example, you can use f.tell() and f.seek()
2506 to manipulate files larger than 2 gigabytes (provided you have enough
2507 disk space, and are using a Windows filesystem that supports large
Tim Peters9a9471c2001-09-11 23:18:51 +00002508 partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
2509 filesize limit, and large file support makes no difference there.
2510 FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
2511 NTFS has no practical limit on file size, and files of any size can be
2512 used from Python now.
Tim Peters6e13a562001-09-06 00:32:15 +00002513
Tim Petersbdee63f2001-09-02 03:40:59 +00002514- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
Tim Peters402d5982001-08-27 06:37:48 +00002515 points to command.com (patch from Brian Quinlan).
2516
Tim Petersedc99312001-08-22 21:36:50 +00002517
Tim Peters20f51a72001-07-21 02:31:40 +00002518What's New in Python 2.2a2?
2519===========================
2520
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002521*Release Date: 22-Aug-2001*
2522
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002523Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002524-----
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002525
Barry Warsaw18b2ecf2001-08-22 20:26:56 +00002526- Tim Peters developed a brand new Windows installer using Wise 8.1,
2527 generously donated to us by Wise Solutions.
2528
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002529- configure supports a new option --enable-unicode, with the values
2530 ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
2531 type and supporting code is completely removed from the interpreter.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002532
Jack Jansen32ce0cd2001-08-21 19:28:20 +00002533- A new configure option --enable-framework builds a Mac OS X framework,
2534 which "make frameworkinstall" will install. This provides a starting
2535 point for more mac-like functionality, join pythonmac-sig@python.org
2536 if you are interested in helping.
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002537
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002538- The NeXT platform is no longer supported.
2539
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002540- The 'new' module is now statically linked.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002541
Tim Peters0afb6092001-08-15 06:06:44 +00002542Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002543-----
Tim Peters0afb6092001-08-15 06:06:44 +00002544
2545- The new Tools/scripts/cleanfuture.py can be used to automatically
Andrew M. Kuchlingb0532092001-08-15 15:54:56 +00002546 edit out obsolete future statements from Python source code. See
Tim Peters0afb6092001-08-15 06:06:44 +00002547 the module docstring for details.
2548
Tim Peters20f51a72001-07-21 02:31:40 +00002549Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002550-----
Tim Peters20f51a72001-07-21 02:31:40 +00002551
Tim Peters5e824c32001-08-12 22:25:01 +00002552- regrtest.py now knows which tests are expected to be skipped on some
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002553 platforms, allowing to give clearer test result output. regrtest
2554 also has optional --use/-u switch to run normally disabled tests
2555 which require network access or consume significant disk resources.
Tim Peters5e824c32001-08-12 22:25:01 +00002556
Tim Peters20f51a72001-07-21 02:31:40 +00002557- Several new tests in the standard test suite, with special thanks to
2558 Nick Mathewson.
2559
2560Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002561----
Tim Peters20f51a72001-07-21 02:31:40 +00002562
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002563- The floor division operator // has been added as outlined in PEP
2564 238. The / operator still provides classic division (and will until
2565 Python 3.0) unless "from __future__ import division" is included, in
2566 which case the / operator will provide true division. The operator
2567 module provides truediv() and floordiv() functions. Augmented
2568 assignment variants are included, as are the equivalent overloadable
2569 methods and C API methods. See the PEP for a full discussion:
2570 <http://python.sf.net/peps/pep-0238.html>
2571
Tim Peters6cd6a822001-08-17 22:11:27 +00002572- Future statements are now effective in simulated interactive shells
2573 (like IDLE). This should "just work" by magic, but read Michael
2574 Hudson's "Future statements in simulated shells" PEP 264 for full
2575 details: <http://python.sf.net/peps/pep-0264.html>.
2576
Guido van Rossumf86ddd22001-08-17 21:21:04 +00002577- The type/class unification (PEP 252-253) was integrated into the
2578 trunk and is not so tentative any more (the exact specification of
2579 some features is still tentative). A lot of work has done on fixing
2580 bugs and adding robustness and features (performance still has to
2581 come a long way).
2582
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002583- Warnings about a mismatch in the Python API during extension import
2584 now use the Python warning framework (which makes it possible to
2585 write filters for these warnings).
2586
Barry Warsaw9b3be7f2001-08-14 18:35:02 +00002587- A function's __dict__ (aka func_dict) will now always be a
2588 dictionary. It used to be possible to delete it or set it to None,
2589 but now both actions raise TypeErrors. It is still legal to set it
2590 to a dictionary object. Getting func.__dict__ before any attributes
2591 have been assigned now returns an empty dictionary instead of None.
2592
Guido van Rossum32aa5d22001-09-05 18:43:35 +00002593- A new command line option, -E, was added which disables the use of
2594 all environment variables, or at least those that are specifically
2595 significant to Python. Usually those have a name starting with
2596 "PYTHON". This was used to fix a problem where the tests fail if
2597 the user happens to have PYTHONHOME or PYTHONPATH pointing to an
2598 older distribution.
2599
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002600Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002601-------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002602
Tim Peters5e824c32001-08-12 22:25:01 +00002603- New class Differ and new functions ndiff() and restore() in difflib.py.
2604 These package the algorithms used by the popular Tools/scripts/ndiff.py,
Tim Peters0afb6092001-08-15 06:06:44 +00002605 for programmatic reuse.
Tim Peters5e824c32001-08-12 22:25:01 +00002606
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002607- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
2608 value using the minimal quoting required for the value; more
2609 reliable than using xml.sax.saxutils.escape() for attribute values.
2610
2611- Readline completion support for cmd.Cmd was added.
2612
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002613- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
2614
2615- Added function threading.BoundedSemaphore()
2616
2617- Added Ka-Ping Yee's cgitb.py module.
2618
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002619- The 'new' module now exposes the CO_xxx flags.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002620
Martin v. Löwis560da622001-11-24 09:24:51 +00002621- The gc module offers the get_referents function.
2622
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002623New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002624-------------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002625
2626C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002627-----
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002628
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002629- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
2630 which provide a cross-platform implementations for the
2631 relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
2632 the standard sprintf() and vsprintf() C lib APIs, these versions
2633 apply bounds checking on the used buffer which enhances protection
2634 against buffer overruns.
2635
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002636- Unicode APIs now use name mangling to assure that mixing interpreters
Tim Petersc1731372001-08-04 08:12:36 +00002637 and extensions using different Unicode widths is rendered next to
2638 impossible. Trying to import an incompatible Unicode-aware extension
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002639 will result in an ImportError. Unicode extensions writers must make
2640 sure to check the Unicode width compatibility in their extensions by
2641 using at least one of the mangled Unicode APIs in the extension.
2642
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002643- Two new flags METH_NOARGS and METH_O are available in method definition
2644 tables to simplify implementation of methods with no arguments and a
2645 single untyped argument. Calling such methods is more efficient than
2646 calling corresponding METH_VARARGS methods. METH_OLDARGS is now
2647 deprecated.
2648
Tim Petersc1731372001-08-04 08:12:36 +00002649Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002650-------
Tim Petersc1731372001-08-04 08:12:36 +00002651
2652- "import module" now compiles module.pyw if it exists and nothing else
2653 relevant is found.
2654
Tim Peters20f51a72001-07-21 02:31:40 +00002655
Guido van Rossum55a78992001-07-17 17:22:32 +00002656What's New in Python 2.2a1?
Tim Petersf553f892001-05-01 20:45:31 +00002657===========================
2658
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002659*Release date: 18-Jul-2001*
2660
Tim Petersf553f892001-05-01 20:45:31 +00002661Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002662----
Tim Petersa814db52001-05-14 07:05:58 +00002663
Tim Peters6d6c1a32001-08-02 04:15:00 +00002664- TENTATIVELY, a large amount of code implementing much of what's
2665 described in PEP 252 (Making Types Look More Like Classes) and PEP
2666 253 (Subtyping Built-in Types) was added. This will be released
2667 with Python 2.2a1. Documentation will be provided separately
2668 through http://www.python.org/2.2/. The purpose of releasing this
2669 with Python 2.2a1 is to test backwards compatibility. It is
2670 possible, though not likely, that a decision is made not to release
2671 this code as part of 2.2 final, if any serious backwards
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002672 incompatibilities are found during alpha testing that cannot be
Tim Peters6d6c1a32001-08-02 04:15:00 +00002673 repaired.
2674
Guido van Rossum55a78992001-07-17 17:22:32 +00002675- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +00002676 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +00002677 more 'yield' statements. See PEP 255. Since this adds a new
2678 keyword to the language, this feature must be enabled by including a
2679 future statement: "from __future__ import generators" (see PEP 236).
2680 Generators will become a standard feature in a future release
2681 (probably 2.3). Without this future statement, 'yield' remains an
2682 ordinary identifier, but a warning is issued each time it is used.
2683 (These warnings currently don't conform to the warnings framework of
2684 PEP 230; we intend to fix this in 2.2a2.)
2685
Marc-André Lemburg12e74b32001-05-22 08:58:23 +00002686- The UTF-16 codec was modified to be more RFC compliant. It will now
2687 only remove BOM characters at the start of the string and then
2688 only if running in native mode (UTF-16-LE and -BE won't remove a
2689 leading BMO character).
2690
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002691- Strings now have a new method .decode() to complement the already
2692 existing .encode() method. These two methods provide direct access
2693 to the corresponding decoders and encoders of the registered codecs.
2694
2695 To enhance the usability of the .encode() method, the special
2696 casing of Unicode object return values was dropped (Unicode objects
2697 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +00002698
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002699 Both methods will now return whatever the codec in charge of the
2700 requested encoding returns as object, e.g. Unicode codecs will
2701 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
2702 will return u"äöü"). This enables codec writer to create codecs
2703 for various simple to use conversions.
2704
2705 New codecs were added to demonstrate these new features (the .encode()
2706 and .decode() columns indicate the type of the returned objects):
2707
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002708 +---------+-----------+-----------+-----------------------------+
2709 |Name | .encode() | .decode() | Description |
2710 +=========+===========+===========+=============================+
2711 |uu | string | string | UU codec (e.g. for email) |
2712 +---------+-----------+-----------+-----------------------------+
2713 |base64 | string | string | base64 codec |
2714 +---------+-----------+-----------+-----------------------------+
2715 |quopri | string | string | quoted-printable codec |
2716 +---------+-----------+-----------+-----------------------------+
2717 |zlib | string | string | zlib compression |
2718 +---------+-----------+-----------+-----------------------------+
2719 |hex | string | string | 2-byte hex codec |
2720 +---------+-----------+-----------+-----------------------------+
2721 |rot-13 | string | Unicode | ROT-13 Unicode charmap codec|
2722 +---------+-----------+-----------+-----------------------------+
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002723
Mark Hammond2a0af792001-05-14 03:09:36 +00002724- Some operating systems now support the concept of a default Unicode
2725 encoding for file system operations. Notably, Windows supports 'mbcs'
2726 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002727 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +00002728 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002729
2730 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +00002731 functions that return filenames (such as os.listdir()) to return Python
2732 string objects pre-encoded using the default file system encoding for
2733 the platform. As this encoding is likely to be different from Python's
2734 default encoding, converting this name to a Unicode object before passing
2735 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +00002736 would attempt to use its default encoding (generally ASCII) rather than
2737 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002738
Tim Petersa814db52001-05-14 07:05:58 +00002739 In general, this change simply removes surprises when working with
2740 Unicode and the file system, making these operations work as you expect,
2741 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +00002742 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +00002743
Tim Peters61dff2b2001-05-08 15:43:37 +00002744- Float (and complex) literals in source code were evaluated to full
2745 precision only when running from a .py file; the same code loaded from a
2746 .pyc (or .pyo) file could suffer numeric differences starting at about the
2747 12th significant decimal digit. For example, on a machine with IEEE-754
2748 floating arithmetic,
2749
2750 x = 9007199254740992.0
2751 print long(x)
2752
2753 printed 9007199254740992 if run directly from .py, but 9007199254740000
2754 if from a compiled (.pyc or .pyo) file. This was due to marshal using
2755 str(float) instead of repr(float) when building code objects. marshal
2756 now uses repr(float) instead, which should reproduce floats to full
2757 machine precision (assuming the platform C float<->string I/O conversion
2758 functions are of good quality).
2759
2760 This may cause floating-point results to change in some cases, and
2761 usually for the better, but may also cause numerically unstable
2762 algorithms to break.
2763
Tim Peters2f228e72001-05-13 00:19:31 +00002764- The implementation of dicts suffers fewer collisions, which has speed
2765 benefits. However, the order in which dict entries appear in dict.keys(),
2766 dict.values() and dict.items() may differ from previous releases for a
2767 given dict. Nothing is defined about this order, so no program should
2768 rely on it. Nevertheless, it's easy to write test cases that rely on the
2769 order by accident, typically because of printing the str() or repr() of a
2770 dict to an "expected results" file. See Lib/test/test_support.py's new
2771 sortdict(dict) function for a simple way to display a dict in sorted
2772 order.
2773
Tim Peters7a3bfc32001-06-12 01:22:22 +00002774- Many other small changes to dicts were made, resulting in faster
2775 operation along the most common code paths.
2776
Guido van Rossum10315822001-05-01 20:54:30 +00002777- Dictionary objects now support the "in" operator: "x in dict" means
2778 the same as dict.has_key(x).
2779
Barry Warsaw51acc8d2001-06-26 20:12:50 +00002780- The update() method of dictionaries now accepts generic mapping
2781 objects. Specifically the argument object must support the .keys()
2782 and __getitem__() methods. This allows you to say, for example,
2783 {}.update(UserDict())
2784
Guido van Rossum10315822001-05-01 20:54:30 +00002785- Iterators were added; this is a generalized way of providing values
2786 to a for loop. See PEP 234. There's a new built-in function iter()
2787 to return an iterator. There's a new protocol to get the next value
2788 from an iterator using the next() method (in Python) or the
2789 tp_iternext slot (in C). There's a new protocol to get iterators
2790 using the __iter__() method (in Python) or the tp_iter slot (in C).
2791 Iterating (i.e. a for loop) over a dictionary generates its keys.
2792 Iterating over a file generates its lines.
2793
Tim Petersf553f892001-05-01 20:45:31 +00002794- The following functions were generalized to work nicely with iterator
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002795 arguments::
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002796
Tim Peterse63415e2001-05-08 04:38:29 +00002797 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +00002798 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
2799 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +00002800 join() method of strings
2801 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +00002802 'x in y' and 'x not in y' (PySequence_Contains() in C API)
2803 operator.countOf() (PySequence_Count() in C API)
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002804 right-hand side of assignment statements with multiple targets, such as ::
Tim Petersd6d010b2001-06-21 02:49:55 +00002805 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +00002806
Tim Petersd85e1022001-05-11 21:51:48 +00002807- Accessing module attributes is significantly faster (for example,
2808 random.random or os.path or yourPythonModule.yourAttribute).
2809
Tim Peterse63415e2001-05-08 04:38:29 +00002810- Comparing dictionary objects via == and != is faster, and now works even
2811 if the keys and values don't support comparisons other than ==.
2812
Tim Peters95bf9392001-05-10 08:32:44 +00002813- Comparing dictionaries in ways other than == and != is slower: there were
2814 insecurities in the dict comparison implementation that could cause Python
2815 to crash if the element comparison routines for the dict keys and/or
2816 values mutated the dicts. Making the code bulletproof slowed it down.
2817
Tim Peterseb28ef22001-06-02 05:27:19 +00002818- Collisions in dicts are resolved via a new approach, which can help
2819 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +00002820 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +00002821 faster now. Thanks to Christian Tismer for pointing out the cause and
2822 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +00002823
Tim Peters52e155e2001-06-16 05:42:57 +00002824- repr() is much faster for large containers (dict, list, tuple).
2825
2826
Tim Petersa814db52001-05-14 07:05:58 +00002827Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002828-------
Tim Petersa814db52001-05-14 07:05:58 +00002829
Fred Drake960fdf92001-07-20 18:38:26 +00002830- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002831 were added to the string module. These a locale-independent
Fred Drake960fdf92001-07-20 18:38:26 +00002832 constants, unlike letters, lowercase, and uppercase. These are now
2833 use in appropriate locations in the standard library.
2834
Martin v. Löwisf0473d52001-07-18 16:17:16 +00002835- The flags used in dlopen calls can now be configured using
2836 sys.setdlopenflags and queried using sys.getdlopenflags.
2837
Guido van Rossumc7e4aca2001-07-12 11:54:37 +00002838- Fredrik Lundh's xmlrpclib is now a standard library module. This
2839 provides full client-side XML-RPC support. In addition,
2840 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
2841 one asyncore-based). Thanks to Eric Raymond for the documentation.
2842
Guido van Rossum643d3912001-07-05 14:46:25 +00002843- The xrange() object is simplified: it no longer supports slicing,
2844 repetition, comparisons, efficient 'in' checking, the tolist()
2845 method, or the start, stop and step attributes. See PEP 260.
2846
Martin v. Löwisebf94db2001-06-06 06:25:40 +00002847- A new function fnmatch.filter to filter lists of file names was added.
2848
Barry Warsawffd674d2001-05-22 16:00:10 +00002849- calendar.py uses month and day names based on the current locale.
2850
Guido van Rossum2e0a6542001-05-15 02:14:44 +00002851- strop is now *really* obsolete (this was announced before with 1.6),
2852 and issues DeprecationWarning when used (except for the four items
2853 that are still imported into string.py).
2854
Tim Petersa814db52001-05-14 07:05:58 +00002855- Cookie.py now sorts key+value pairs by key in output strings.
2856
2857- pprint.isrecursive(object) didn't correctly identify recursive objects.
2858 Now it does.
2859
Tim Peters95b3f782001-05-14 18:39:41 +00002860- pprint functions now much faster for large containers (tuple, list, dict).
2861
Tim Peters7b9542a2001-06-10 23:40:19 +00002862- New 'q' and 'Q' format codes in the struct module, corresponding to C
2863 types "long long" and "unsigned long long" (on Windows, __int64). In
2864 native mode, these can be used only when the platform C compiler supports
2865 these types (when HAVE_LONG_LONG is #define'd by the Python config
2866 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +00002867 In standard mode, 'q' and 'Q' are supported on all platforms, and are
2868 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +00002869
Guido van Rossum83213cc2001-06-12 16:48:52 +00002870- The site module installs a new built-in function 'help' that invokes
2871 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
2872 it displays a message reminding the user to use 'help()' or
2873 'help(object)'.
2874
Tim Petersa814db52001-05-14 07:05:58 +00002875Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002876-----
Tim Petersa814db52001-05-14 07:05:58 +00002877
2878- New test_mutants.py runs dict comparisons where the key and value
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002879 comparison operators mutate the dicts randomly during comparison. This
Tim Petersa814db52001-05-14 07:05:58 +00002880 rapidly causes Python to crash under earlier releases (not for the faint
2881 of heart: it can also cause Win9x to freeze or reboot!).
2882
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002883- New test_pprint.py verifies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +00002884 pprint.isreadable() return sensible results. Also verifies that simple
2885 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +00002886
Tim Peters4324aa32001-05-28 22:30:08 +00002887C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002888-----
Tim Peters4324aa32001-05-28 22:30:08 +00002889
2890- Removed the unused last_is_sticky argument from the internal
2891 _PyTuple_Resize(). If this affects you, you were cheating.
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002892
2893----
2894
2895**(For information about older versions, consult the HISTORY file.)**