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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
Tim Peters6ee04802003-02-05 18:29:34 +0000227- array.array was added to the types repr.py knows about (see
228 <http://www.python.org/sf/680789>).
229
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000230- The new pickletools.py contains lots of documentation about pickle
231 internals, and supplies some helpers for working with pickles, such as
232 a symbolic pickle disassembler.
233
Skip Montanaro9a7c96a2003-01-22 18:17:25 +0000234- Xmlrpclib.py now supports the builtin boolean type.
235
Martin v. Löwis0c6774d2003-01-15 11:51:06 +0000236- py_compile has a new 'doraise' flag and a new PyCompileError
237 exception.
238
Martin v. Löwisd69663d2003-01-15 11:37:23 +0000239- SimpleXMLRPCServer now supports CGI through the CGIXMLRPCRequestHandler
240 class.
241
Guido van Rossum50e92232003-01-14 16:45:04 +0000242- The sets module now raises TypeError in __cmp__, to clarify that
243 sets are not intended to be three-way-compared; the comparison
244 operators are overloaded as subset/superset tests.
245
Guido van Rossumcd0c0472003-01-07 23:03:05 +0000246- Bastion.py and rexec.py are disabled. These modules are not safe in
247 Python 2.2. or 2.3.
248
Neal Norwitzbb0246a2003-01-03 18:12:28 +0000249- realpath is now exported when doing from poxixpath import *.
250 It is also exported for ntpath, macpath, and os2emxpath.
251 See SF bug #659228.
252
Neal Norwitzb9ef4ae2003-01-05 23:19:43 +0000253- New module tarfile from Lars Gustäbel provides a comprehensive interface
254 to tar archive files with transparent gzip and bzip2 compression.
255 See SF patch #651082.
256
Neal Norwitz4f442372003-01-06 06:51:36 +0000257- urlparse can now parse imap:// URLs. See SF feature request #618024.
David Goodgerf349e262003-01-03 03:30:21 +0000258
Neal Norwitze931ed52003-01-10 23:24:32 +0000259- Tkinter.Canvas.scan_dragto() provides an optional parameter to support
260 the gain value which is passed to Tk. SF bug# 602259.
261
Neal Norwitze4c40da2003-01-26 02:45:47 +0000262- Fix logging.handlers.SysLogHandler protocol when using UNIX domain sockets.
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000263 See SF patch #642974.
Neal Norwitze4c40da2003-01-26 02:45:47 +0000264
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000265Tools/Demos
266-----------
267
Skip Montanaro13b29102003-02-03 15:17:25 +0000268- Two new scripts (db2pickle.py and pickle2db.py) were added to the
269 Tools/scripts directory to facilitate conversion from the old bsddb module
270 to the new one. While the user-visible API of the new module is
271 compatible with the old one, it's likely that the version of the
272 underlying database library has changed. To convert from the old library,
273 run the db2pickle.py script using the old version of Python to convert it
274 to a pickle file. After upgrading Python, run the pickle2db.py script
275 using the new version of Python to reconstitute your database. For
276 example:
277
Skip Montanaro621f0552003-02-03 15:48:10 +0000278 % python2.2 db2pickle.py -h some.db > some.pickle
279 % python2.3 pickle2db.py -h some.db.new < some.pickle
Skip Montanaro13b29102003-02-03 15:17:25 +0000280
281 Run the scripts without any args to get a usage message.
282
David Goodgerf349e262003-01-03 03:30:21 +0000283
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000284Build
285-----
286
Guido van Rossum4507ec72003-02-14 19:29:22 +0000287- The audio driver tests (test_ossaudiodev.py and
288 test_linuxaudiodev.py) are no longer run by default. This is
289 because they don't always work, depending on your hardware and
290 software. To run these tests, you must use an invocation like
291 ./python Lib/test/regrtest.py -u audio test_ossaudiodev
292
Skip Montanarodecc6a42003-01-01 20:07:49 +0000293- On systems which build using the configure script, compiler flags which
294 used to be lumped together using the OPT flag have been split into two
295 groups, OPT and BASECFLAGS. OPT is meant to carry just optimization- and
296 debug-related flags like "-g" and "-O3". BASECFLAGS is meant to carry
297 compiler flags that are required to get a clean compile. On some
298 platforms (many Linux flavors in particular) BASECFLAGS will be empty by
299 default. On others, such as Mac OS X and SCO, it will contain required
300 flags. This change allows people building Python to override OPT without
301 fear of clobbering compiler flags which are required to get a clean build.
302
303- On Darwin/Mac OS X platforms, /sw/lib and /sw/include are added to the
304 relevant search lists in setup.py. This allows users building Python to
305 take advantage of the many packages available from the fink project
306 <http://fink.sf.net/>.
307
308- A new Makefile target, scriptsinstall, installs a number of useful scripts
309 from the Tools/scripts directory.
310
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000311C API
312-----
313
Guido van Rossumeea47182003-02-11 20:39:59 +0000314- A C type that inherits from a base type that defines tp_as_buffer
315 will now inherit the tp_as_buffer pointer if it doesn't define one.
316 (SF #681367)
317
Neil Schemenauer5042da62003-02-04 20:59:40 +0000318- The PyArg_Parse functions now issue a DeprecationWarning if a float
319 argument is provided when an integer is specified (this affects the 'b',
320 'B', 'h', 'H', 'i', and 'l' codes). Future versions of Python will
321 raise a TypeError.
Neil Schemenauercd63e612003-01-24 22:15:53 +0000322
David Goodgerf349e262003-01-03 03:30:21 +0000323
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000324New platforms
325-------------
326
David Goodgerf349e262003-01-03 03:30:21 +0000327TBD
328
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000329Tests
330-----
331
David Goodgerf349e262003-01-03 03:30:21 +0000332TBD
333
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000334Windows
335-------
336
Thomas Hellerdda583d2003-01-31 20:45:41 +0000337- distutils' msvccompiler class now passes the preprocessor options to
338 the resource compiler. See SF patch #669198.
339
Tim Peters00640262003-01-24 15:31:31 +0000340- The bsddb module now ships with Sleepycat's 4.1.25.NC, the latest
341 release without strong cryptography.
342
Thomas Heller6c64fa72003-01-08 15:14:55 +0000343- sys.path[0], if it contains a directory name, is now always an
344 absolute pathname.
345
Tim Petersbbc5d162003-01-02 16:02:27 +0000346- The new logging package is now installed by the Windows installer. It
347 wasn't in 2.3a1 due to oversight.
348
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000349Mac
350---
351
Jack Jansen1a1b6e42003-01-27 15:21:39 +0000352- There are new dialogs EasyDialogs.AskFileForOpen, AskFileForSave
353 and AskFolder. The old macfs.StandardGetFile and friends are deprecated.
Tim Peters07534a62003-02-07 22:50:28 +0000354
Jack Jansenc9296362003-02-06 23:10:45 +0000355- Most of the standard library now uses pathnames or FSRefs in preference
356 of FSSpecs, and use the underlying Carbon.File and Carbon.Folder modules
357 in stead of macfs. macfs will probably be deprecated in the future.
Tim Peters8ecfc8e2003-01-27 18:51:48 +0000358
Jack Jansen1a1b6e42003-01-27 15:21:39 +0000359- Type Carbon.File.FSCatalogInfo and supporting methods have been implemented.
360 This also makes macfs.FSSpec.SetDates() work again.
Jack Jansen9f70aab2003-02-16 23:00:53 +0000361
362- There is a new module pimp, the package install manager for Python, and
363 accompanying applet PackageManager. These allow you to easily download
364 and install pretested extension packages either in source or binary
365 form. Only in MacPython-OSX.
366
367- Applets are now built with bundlebuilder in MacPython-OSX, which should make
368 them more robust and also provides a path towards BuildApplication.
David Goodgerf349e262003-01-03 03:30:21 +0000369
Martin v. Löwis14e73b12003-01-01 09:51:12 +0000370
Tim Petersaf8446f2001-12-21 21:36:50 +0000371What's New in Python 2.3 alpha 1?
Tim Petersaf8446f2001-12-21 21:36:50 +0000372=================================
373
Guido van Rossumae548862002-12-31 15:47:36 +0000374*Release date: 31-Dec-2002*
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000375
Tim Petersaf8446f2001-12-21 21:36:50 +0000376Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000377--------------------------------------------
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000378
Michael W. Hudson96bc3b42002-11-26 14:48:23 +0000379- One can now assign to __bases__ and __name__ of new-style classes.
380
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000381- dict() now accepts keyword arguments so that dict(one=1, two=2)
382 is the equivalent of {"one": 1, "two": 2}. Accordingly,
Just van Rossuma797d812002-11-23 09:45:04 +0000383 the existing (but undocumented) 'items' keyword argument has
Guido van Rossum8b1e74b2002-11-23 16:28:12 +0000384 been eliminated. This means that dict(items=someMapping) now has
Just van Rossuma797d812002-11-23 09:45:04 +0000385 a different meaning than before.
386
Walter Dörwaldf1715402002-11-19 20:49:15 +0000387- int() now returns a long object if the argument is outside the
David Goodgerf349e262003-01-03 03:30:21 +0000388 integer range, so int("4" * 1000), int(1e200) and int(1L<<1000) will
Walter Dörwaldf1715402002-11-19 20:49:15 +0000389 all return long objects instead of raising an OverflowError.
Tim Petersaf8446f2001-12-21 21:36:50 +0000390
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000391- Assignment to __class__ is disallowed if either the old or the new
Guido van Rossume3438782002-08-12 03:42:03 +0000392 class is a statically allocated type object (such as defined by an
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000393 extension module). This prevents anomalies like 2.__class__ = bool.
Guido van Rossume3438782002-08-12 03:42:03 +0000394
395- New-style object creation and deallocation have been sped up
396 significantly; they are now faster than classic instance creation
397 and deallocation.
398
399- The __slots__ variable can now mention "private" names, and the
400 right thing will happen (e.g. __slots__ = ["__foo"]).
401
402- The built-ins slice() and buffer() are now callable types. The
403 types classobj (formerly class), code, function, instance, and
404 instancemethod (formerly instance-method), which have no built-in
405 names but are accessible through the types module, are now also
406 callable. The type dict-proxy is renamed to dictproxy.
407
408- Cycles going through the __class__ link of a new-style instance are
409 now detected by the garbage collector.
410
411- Classes using __slots__ are now properly garbage collected.
412 [SF bug 519621]
413
414- Tightened the __slots__ rules: a slot name must be a valid Python
415 identifier.
416
417- The constructor for the module type now requires a name argument and
418 takes an optional docstring argument. Previously, this constructor
419 ignored its arguments. As a consequence, deriving a class from a
420 module (not from the module type) is now illegal; previously this
421 created an unnamed module, just like invoking the module type did.
422 [SF bug 563060]
423
424- A new type object, 'basestring', is added. This is a common base type
425 for 'str' and 'unicode', and can be used instead of
426 types.StringTypes, e.g. to test whether something is "a string":
427 isinstance(x, basestring) is True for Unicode and 8-bit strings. This
428 is an abstract base class and cannot be instantiated directly.
429
430- Changed new-style class instantiation so that when C's __new__
431 method returns something that's not a C instance, its __init__ is
432 not called. [SF bug #537450]
433
434- Fixed super() to work correctly with class methods. [SF bug #535444]
435
436- If you try to pickle an instance of a class that has __slots__ but
437 doesn't define or override __getstate__, a TypeError is now raised.
438 This is done by adding a bozo __getstate__ to the class that always
439 raises TypeError. (Before, this would appear to be pickled, but the
440 state of the slots would be lost.)
441
Tim Petersaf8446f2001-12-21 21:36:50 +0000442Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000443-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000444
Guido van Rossuma3b89532002-12-30 22:59:32 +0000445- Import from zipfiles is now supported. The name of a zipfile placed
Just van Rossum01875eb2002-12-31 10:22:38 +0000446 on sys.path causes the import statement to look for importable Python
447 modules (with .py, pyc and .pyo extensions) and packages inside the
448 zipfile. The zipfile import follows the specification (though not
449 the sample implementation) of PEP 273. The semantics of __path__ are
Guido van Rossuma3b89532002-12-30 22:59:32 +0000450 compatible with those that have been implemented in Jython since
451 Jython 2.1.
452
Just van Rossum01875eb2002-12-31 10:22:38 +0000453- PEP 302 has been accepted. Although it was inititally developed to
Tim Petersbbc5d162003-01-02 16:02:27 +0000454 support zipimport, it offers a new, general import hook mechanism.
Just van Rossum01875eb2002-12-31 10:22:38 +0000455 Several new variables have been added to the sys module:
456 sys.meta_path, sys.path_hooks, and sys.path_importer_cache; these
457 make extending the import statement much more convenient than
458 overriding the __import__ built-in function. For a description of
459 these, see PEP 302.
460
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000461- A frame object's f_lineno attribute can now be written to from a
462 trace function to change which line will execute next. A command to
463 exploit this from pdb has been added. [SF patch #643835]
464
Marc-André Lemburg20b91352002-12-12 18:01:43 +0000465- The _codecs support module for codecs.py was turned into a builtin
466 module to assure that at least the builtin codecs are available
467 to the Python parser for source code decoding according to PEP 263.
468
Walter Dörwaldd9a6ad32002-12-12 16:41:44 +0000469- issubclass now supports a tuple as the second argument, just like
470 isinstance does. ``issubclass(X, (A, B))`` is equivalent to
471 ``issubclass(X, A) or issubclass(X, B)``.
472
Tim Petersb9099c32002-11-12 22:08:10 +0000473- Thanks to Armin Rigo, the last known way to provoke a system crash
474 by cleverly arranging for a comparison function to mutate a list
475 during a list.sort() operation has been fixed. The effect of
476 attempting to mutate a list, or even to inspect its contents or
477 length, while a sort is in progress, is not defined by the language.
478 The C implementation of Python 2.3 attempts to detect mutations,
479 and raise ValueError if one occurs, but there's no guarantee that
480 all mutations will be caught, or that any will be caught across
481 releases or implementations.
482
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000483- Unicode file name processing for Windows (PEP 277) is implemented.
Mark Hammond8696ebc2002-10-08 02:44:31 +0000484 All platforms now have an os.path.supports_unicode_filenames attribute,
485 which is set to True on Windows NT/2000/XP, and False elsewhere.
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000486
Walter Dörwald3aeb6322002-09-02 13:14:32 +0000487- Codec error handling callbacks (PEP 293) are implemented.
488 Error handling in unicode.encode or str.decode can now be customized.
489
Guido van Rossum45ec02a2002-08-19 21:43:18 +0000490- A subtle change to the semantics of the built-in function intern():
491 interned strings are no longer immortal. You must keep a reference
492 to the return value intern() around to get the benefit.
493
Guido van Rossumf808b892002-08-16 03:38:10 +0000494- Use of 'None' as a variable, argument or attribute name now
495 issues a SyntaxWarning. In the future, None may become a keyword.
496
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000497- SET_LINENO is gone. co_lnotab is now consulted to determine when to
498 call the trace function. C code that accessed f_lineno should call
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000499 PyCode_Addr2Line instead (f_lineno is still there, but only kept up
500 to date when there is a trace function set).
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000501
Guido van Rossum9be89462002-08-14 16:11:30 +0000502- There's a new warning category, FutureWarning. This is used to warn
503 about a number of situations where the value or sign of an integer
504 result will change in Python 2.4 as a result of PEP 237 (integer
505 unification). The warnings implement stage B0 mentioned in that
506 PEP. The warnings are about the following situations:
507
508 - Octal and hex literals without 'L' prefix in the inclusive range
509 [0x80000000..0xffffffff]; these are currently negative ints, but
510 in Python 2.4 they will be positive longs with the same bit
511 pattern.
512
513 - Left shifts on integer values that cause the outcome to lose
514 bits or have a different sign than the left operand. To be
515 precise: x<<n where this currently doesn't yield the same value
516 as long(x)<<n; in Python 2.4, the outcome will be long(x)<<n.
517
518 - Conversions from ints to string that show negative values as
519 unsigned ints in the inclusive range [0x80000000..0xffffffff];
520 this affects the functions hex() and oct(), and the string
521 formatting codes %u, %o, %x, and %X. In Python 2.4, these will
522 show signed values (e.g. hex(-1) currently returns "0xffffffff";
523 in Python 2.4 it will return "-0x1").
524
Guido van Rossum9a2eda52002-12-31 02:12:42 +0000525- The bits manipulated under the cover by sys.setcheckinterval() have
526 been changed. Both the check interval and the ticker used to be
527 per-thread values. They are now just a pair of global variables.
528 In addition, the default check interval was boosted from 10 to 100
529 bytecode instructions. This may have some effect on systems that
530 relied on the old default value. In particular, in multi-threaded
531 applications which try to be highly responsive, response time will
532 increase by some (perhaps imperceptible) amount.
Skip Montanaro979c74b2002-09-03 21:25:14 +0000533
Tim Petersd64c1de2002-08-12 17:36:03 +0000534- When multiplying very large integers, a version of the so-called
535 Karatsuba algorithm is now used. This is most effective if the
536 inputs have roughly the same size. If they both have about N digits,
537 Karatsuba multiplication has O(N**1.58) runtime (the exponent is
538 log_base_2(3)) instead of the previous O(N**2). Measured results may
Tim Peters012c0a32002-08-16 03:40:07 +0000539 be better or worse than that, depending on platform quirks. Besides
540 the O() improvement in raw instruction count, the Karatsuba algorithm
541 appears to have much better cache behavior on extremely large integers
542 (starting in the ballpark of a million bits). Note that this is a
543 simple implementation, and there's no intent here to compete with,
544 e.g., GMP. It gives a very nice speedup when it applies, but a package
545 devoted to fast large-integer arithmetic should run circles around it.
Tim Peters5af4e6c2002-08-12 02:31:19 +0000546
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000547- u'%c' will now raise a ValueError in case the argument is an
548 integer outside the valid range of Unicode code point ordinals.
549
Guido van Rossumdeb09362002-08-09 17:16:30 +0000550- The tempfile module has been overhauled for enhanced security. The
551 mktemp() function is now deprecated; new, safe replacements are
552 mkstemp() (for files) and mkdtemp() (for directories), and the
553 higher-level functions NamedTemporaryFile() and TemporaryFile().
554 Use of some global variables in this module is also deprecated; the
555 new functions have keyword arguments to provide the same
556 functionality. All Lib, Tools and Demo modules that used the unsafe
557 interfaces have been updated to use the safe replacements. Thanks
558 to Zack Weinberg!
559
Guido van Rossumd81a9832002-08-09 15:57:34 +0000560- When x is an object whose class implements __mul__ and __rmul__,
561 1.0*x would correctly invoke __rmul__, but 1*x would erroneously
562 invoke __mul__. This was due to the sequence-repeat code in the int
563 type. This has been fixed now.
564
Barry Warsawd79f6832002-08-06 17:01:51 +0000565- Previously, "str1 in str2" required str1 to be a string of length 1.
566 This restriction has been relaxed to allow str1 to be a string of
567 any length. Thus "'el' in 'hello world'" returns True now.
568
Guido van Rossumb57089c2002-08-06 16:20:26 +0000569- File objects are now their own iterators. For a file f, iter(f) now
570 returns f (unless f is closed), and f.next() is similar to
571 f.readline() when EOF is not reached; however, f.next() uses a
572 readahead buffer that messes up the file position, so mixing
573 f.next() and f.readline() (or other methods) doesn't work right.
574 Calling f.seek() drops the readahead buffer, but other operations
575 don't. It so happens that this gives a nice additional speed boost
576 to "for line in file:"; the xreadlines method and corresponding
Guido van Rossumbffb2ef2002-08-09 17:17:07 +0000577 module are now obsolete. Thanks to Oren Tirosh!
Guido van Rossumb57089c2002-08-06 16:20:26 +0000578
Guido van Rossumde392d32002-08-05 14:17:20 +0000579- Encoding declarations (PEP 263, phase 1) have been implemented. A
580 comment of the form "# -*- coding: <encodingname> -*-" in the first
581 or second line of a Python source file indicates the encoding.
Martin v. Löwis00f1e3f2002-08-04 17:29:52 +0000582
Tim Petersf47630f2002-08-01 02:34:51 +0000583- list.sort() has a new implementation. While cross-platform results
584 may vary, and in data-dependent ways, this is much faster on many
585 kinds of partially ordered lists than the previous implementation,
586 and reported to be just as fast on randomly ordered lists on
587 several major platforms. This sort is also stable (if A==B and A
588 precedes B in the list at the start, A precedes B after the sort too),
589 although the language definition does not guarantee stability. A
590 potential drawback is that list.sort() may require temp space of
Skip Montanaroa2a07bc2002-09-30 15:23:01 +0000591 len(list)*2 bytes (``*4`` on a 64-bit machine). It's therefore possible
Tim Petersf47630f2002-08-01 02:34:51 +0000592 for list.sort() to raise MemoryError now, even if a comparison function
593 does not. See <http://www.python.org/sf/587076> for full details.
594
Guido van Rossum2d5389c2002-07-23 03:44:35 +0000595- All standard iterators now ensure that, once StopIteration has been
596 raised, all future calls to next() on the same iterator will also
597 raise StopIteration. There used to be various counterexamples to
598 this behavior, which could caused confusion or subtle program
599 breakage, without any benefits. (Note that this is still an
600 iterator's responsibility; the iterator framework does not enforce
601 this.)
602
Mark Hammondc0e35152002-07-16 01:32:30 +0000603- Ctrl+C handling on Windows has been made more consistent with
604 other platforms. KeyboardInterrupt can now reliably be caught,
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000605 and Ctrl+C at an interactive prompt no longer terminates the
Mark Hammondc0e35152002-07-16 01:32:30 +0000606 process under NT/2k/XP (it never did under Win9x). Ctrl+C will
Tim Peters5af4e6c2002-08-12 02:31:19 +0000607 interrupt time.sleep() in the main thread, and any child processes
608 created via the popen family (on win2k; we can't make win9x work
Mark Hammond8f3afc72002-08-10 06:26:31 +0000609 reliably) are also interrupted (as generally happens on for Linux/Unix.)
610 [SF bugs 231273, 439992 and 581232]
Mark Hammondc0e35152002-07-16 01:32:30 +0000611
Mark Hammond8696ebc2002-10-08 02:44:31 +0000612- sys.getwindowsversion() has been added on Windows. This
613 returns a tuple with information about the version of Windows
614 currently running.
615
Raymond Hettinger5a04aec2002-06-25 00:25:30 +0000616- Slices and repetitions of buffer objects now consistently return
617 a string. Formerly, strings would be returned most of the time,
618 but a buffer object would be returned when the repetition count
619 was one or when the slice range was all inclusive.
620
Walter Dörwald3430d702002-06-17 10:43:59 +0000621- Unicode objects in sys.path are no longer ignored but treated
622 as directory names.
623
Neal Norwitz1f68fc72002-06-14 00:50:42 +0000624- Fixed string.startswith and string.endswith builtin methods
625 so they accept negative indices. [SF bug 493951]
626
Guido van Rossumc5fe5eb2002-06-12 03:45:21 +0000627- Fixed a bug with a continue inside a try block and a yield in the
628 finally clause. [SF bug 567538]
629
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000630- Most builtin sequences now support "extended slices", i.e. slices
Guido van Rossum2e82e712002-06-13 11:41:07 +0000631 with a third "stride" parameter. For example, "hello world"[::-1]
632 gives "dlrow olleh".
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000633
Neal Norwitzd68f5172002-05-29 15:54:55 +0000634- A new warning PendingDeprecationWarning was added to provide
635 direction on features which are in the process of being deprecated.
636 The warning will not be printed by default. To see the pending
637 deprecations, use -Walways::PendingDeprecationWarning::
638 as a command line option or warnings.filterwarnings() in code.
639
Fred Draked0ba6362002-05-02 21:28:26 +0000640- Deprecated features of xrange objects have been removed as
641 promised. The start, stop, and step attributes and the tolist()
642 method no longer exist. xrange repetition and slicing have been
643 removed.
644
Guido van Rossum7dab2422002-04-26 19:40:56 +0000645- New builtin function enumerate(x), from PEP 279. Example:
646 enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
647 The argument can be an arbitrary iterable object.
648
Neil Schemenauer89e3ee02002-04-26 01:58:53 +0000649- The assert statement no longer tests __debug__ at runtime. This means
650 that assert statements cannot be disabled by assigning a false value
651 to __debug__.
652
Walter Dörwald068325e2002-04-15 13:36:47 +0000653- A method zfill() was added to str and unicode, that fills a numeric
654 string to the left with zeros. For example,
655 "+123".zfill(6) -> "+00123".
656
Guido van Rossum862fe3c2002-04-15 12:36:47 +0000657- Complex numbers supported divmod() and the // and % operators, but
658 these make no sense. Since this was documented, they're being
659 deprecated now.
660
Guido van Rossum26dd8302002-04-26 20:11:29 +0000661- String and unicode methods lstrip(), rstrip() and strip() now take
662 an optional argument that specifies the characters to strip. For
663 example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
Guido van Rossum49042042002-04-13 00:59:05 +0000664
Guido van Rossumc0d3f4e2002-11-27 13:10:40 +0000665- There's a new dictionary constructor (a class method of the dict
666 class), dict.fromkeys(iterable, value=None). It constructs a
667 dictionary with keys taken from the iterable and all values set to a
668 single value. It can be used for building sets and for removing
669 duplicates from sequences.
Raymond Hettingere33d3df2002-11-27 07:29:33 +0000670
Guido van Rossumc69343b2002-04-12 19:22:48 +0000671- Added a new dict method pop(key). This removes and returns the
672 value corresponding to key. [SF patch #539949]
673
Guido van Rossum47834462002-04-04 15:21:33 +0000674- A new built-in type, bool, has been added, as well as built-in
675 names for its two values, True and False. Comparisons and sundry
676 other operations that return a truth value have been changed to
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000677 return a bool instead. Read PEP 285 for an explanation of why this
Guido van Rossum47834462002-04-04 15:21:33 +0000678 is backward compatible.
679
Guido van Rossum95b62a62002-03-29 01:07:24 +0000680- Fixed two bugs reported as SF #535905: under certain conditions,
681 deallocating a deeply nested structure could cause a segfault in the
682 garbage collector, due to interaction with the "trashcan" code;
683 access to the current frame during destruction of a local variable
684 could access a pointer to freed memory.
685
Guido van Rossumfe0ca4a2002-06-18 21:20:13 +0000686- The optional object allocator ("pymalloc") has been enabled by
687 default. The recommended practice for memory allocation and
688 deallocation has been streamlined. A header file is included,
689 Misc/pymemcompat.h, which can be bundled with 3rd party extensions
690 and lets them use the same API with Python versions from 1.5.2
691 onwards.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000692
Martin v. Löwiscfeb3b62002-03-03 21:30:27 +0000693- PyErr_Display will provide file and line information for all exceptions
694 that have an attribute print_file_and_line, not just SyntaxErrors.
695
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000696- The UTF-8 codec will now encode and decode Unicode surrogates
697 correctly and without raising exceptions for unpaired ones.
698
Guido van Rossumadd88062002-08-15 14:01:14 +0000699- Universal newlines (PEP 278) is implemented. Briefly, using 'U'
700 instead of 'r' when opening a text file for reading changes the line
701 ending convention so that any of '\r', '\r\n', and '\n' is
702 recognized (even mixed in one file); all three are converted to
703 '\n', the standard Python line end character.
704
Neal Norwitz649b7592002-01-01 19:07:13 +0000705- file.xreadlines() now raises a ValueError if the file is closed:
706 Previously, an xreadlines object was returned which would raise
707 a ValueError when the xreadlines.next() method was called.
708
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000709- sys.exit() inadvertently allowed more than one argument.
Neal Norwitz0c766a02002-03-27 13:03:09 +0000710 An exception will now be raised if more than one argument is used.
711
Gustavo Niemeyer17c5a332002-12-16 14:09:22 +0000712- Changed evaluation order of dictionary literals to conform to the
713 general left to right evaluation order rule. Now {f1(): f2()} will
714 evaluate f1 first.
Gustavo Niemeyer78429a62002-12-16 13:54:02 +0000715
Gustavo Niemeyer786ddb22002-12-16 18:12:53 +0000716- Fixed bug #521782: when a file was in non-blocking mode, file.read()
717 could silently lose data or wrongly throw an unknown error.
718
Neil Schemenauerb983aa02002-12-30 20:22:23 +0000719- The sq_repeat, sq_inplace_repeat, sq_concat and sq_inplace_concat
720 slots are now always tried after trying the corresponding nb_* slots.
721 This fixes a number of minor bugs (see bug #624807).
722
Neal Norwitz74a032e2003-01-10 23:29:48 +0000723- Fix problem with dynamic loading on 64-bit AIX (see bug #639945).
724
Tim Petersaf8446f2001-12-21 21:36:50 +0000725Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000726-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000727
Raymond Hettinger9543b342003-01-18 23:22:20 +0000728- Added three operators to the operator module:
729 operator.pow(a,b) which is equivalent to: a**b.
730 operator.is_(a,b) which is equivalent to: a is b.
731 operator.is_not(a,b) which is equivalent to: a is not b.
732
Martin v. Löwis24a880b2002-12-31 12:55:15 +0000733- posix.openpty now works on all systems that have /dev/ptmx.
734
Guido van Rossuma3b89532002-12-30 22:59:32 +0000735- A module zipimport exists to support importing code from zip
736 archives.
737
Tim Peterse820cb62002-12-16 20:57:22 +0000738- The new datetime module supplies classes for manipulating dates and
739 times. The basic design came from the Zope "fishbowl process", and
740 favors practical commercial applications over calendar esoterica. See
741
742 http://www.zope.org/Members/fdrake/DateTimeWiki/FrontPage
743
Martin v. Löwisffad6332002-11-26 09:28:05 +0000744- _tkinter now returns Tcl objects, instead of strings. Objects which
745 have Python equivalents are converted to Python objects, other objects
746 are wrapped. This can be configured through the wantobjects method,
Martin v. Löwis8c8aa5d2002-11-26 21:39:48 +0000747 or Tkinter.wantobjects.
Martin v. Löwisffad6332002-11-26 09:28:05 +0000748
Barry Warsawc27f4bd2002-12-30 21:03:26 +0000749- The PyBSDDB wrapper around the Sleepycat Berkeley DB library has
750 been added as the package bsddb. The traditional bsddb module is
751 still available in source code, but not built automatically anymore,
752 and is now named bsddb185. This supports Berkeley DB versions from
Skip Montanaro13b29102003-02-03 15:17:25 +0000753 3.0 to 4.1. For help converting your databases from the old module (which
754 probably used an obsolete version of Berkeley DB) to the new module, see
755 the db2pickle.py and pickle2db.py scripts described in the Tools/Demos
756 section above.
Martin v. Löwisef546b32002-11-19 08:12:57 +0000757
Martin v. Löwis677bde22002-11-23 22:08:15 +0000758- unicodedata was updated to Unicode 3.2. It supports normalization
759 and names for Hangul syllables and CJK unified ideographs.
Martin v. Löwis7d41e292002-11-23 12:22:32 +0000760
Neal Norwitz94a83fd2002-11-02 17:46:24 +0000761- resource.getrlimit() now returns longs instead of ints.
762
Martin v. Löwis080689c2002-10-26 14:42:02 +0000763- readline now dynamically adjusts its input/output stream if
764 sys.stdin/stdout changes.
765
Guido van Rossumba602972002-10-01 18:18:58 +0000766- The _tkinter module (and hence Tkinter) has dropped support for
767 Tcl/Tk 8.0 and 8.1. Only Tcl/Tk versions 8.2, 8.3 and 8.4 are
768 supported.
769
Martin v. Löwis658009a2002-09-16 17:26:24 +0000770- cPickle.BadPickleGet is now a class.
771
Martin v. Löwisa19bfe02002-10-16 18:28:36 +0000772- The time stamps in os.stat_result are floating point numbers
773 after stat_float_times has been called.
Martin v. Löwis94717ed2002-09-09 14:24:16 +0000774
Neal Norwitzb5673922002-09-05 21:48:07 +0000775- If the size passed to mmap.mmap() is larger than the length of the
776 file on non-Windows platforms, a ValueError is raised. [SF bug 585792]
777
Guido van Rossumb57089c2002-08-06 16:20:26 +0000778- The xreadlines module is slated for obsolescence.
779
Guido van Rossum79f0a102002-07-23 03:32:08 +0000780- The strptime function in the time module is now always available (a
781 Python implementation is used when the C library doesn't define it).
782
Guido van Rossum9562bcf2002-06-14 21:31:18 +0000783- The 'new' module is no longer an extension, but a Python module that
784 only exists for backwards compatibility. Its contents are no longer
785 functions but callable type objects.
786
Tim Peters81b92512002-04-29 01:37:32 +0000787- The bsddb.*open functions can now take 'None' as a filename.
Anthony Baxter83888952002-04-23 02:11:05 +0000788 This will create a temporary in-memory bsddb that won't be
Tim Peters81b92512002-04-29 01:37:32 +0000789 written to disk.
Anthony Baxter83888952002-04-23 02:11:05 +0000790
Martin v. Löwisb96152c2002-12-31 13:20:15 +0000791- posix.getloadavg, posix.lchown, posix.killpg, posix.mknod, and
792 posix.getpgid have been added where available.
Martin v. Löwis06a83e92002-04-14 10:19:44 +0000793
Martin v. Löwisf0a46682002-11-03 17:20:12 +0000794- The locale module now exposes the C library's gettext interface. It
795 also has a new function getpreferredencoding.
Martin v. Löwis2e64c342002-03-27 18:49:02 +0000796
Tim Petersfbf74f22002-03-14 19:06:01 +0000797- A security hole ("double free") was found in zlib-1.1.3, a popular
798 third party compression library used by some Python modules. The
799 hole was quickly plugged in zlib-1.1.4, and the Windows build of
800 Python now ships with zlib-1.1.4.
801
Martin v. Löwis688357e2002-04-08 21:28:20 +0000802- pwd, grp, and resource return enhanced tuples now, with symbolic
803 field names.
Martin v. Löwis29001ff2002-03-01 10:47:37 +0000804
Martin v. Löwis99866332002-03-01 10:27:01 +0000805- array.array is now a type object. A new format character
806 'u' indicates Py_UNICODE arrays. For those, .tounicode and
807 .fromunicode methods are available. Arrays now support __iadd__
808 and __imul__.
809
Neal Norwitze790eae2002-01-01 21:14:12 +0000810- dl now builds on every system that has dlfcn.h. Failure in case
Martin v. Löwis93227272002-01-01 20:18:30 +0000811 of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
812 is called.
813
Michael W. Hudson34f20ea2002-05-27 15:08:24 +0000814- signal.sigpending, signal.sigprocmask and signal.sigsuspend have
815 been added where available.
816
Skip Montanaro8e790e72002-09-03 13:25:17 +0000817- The sys module acquired a new attribute, api_version, which evaluates
818 to the value of the PYTHON_API_VERSION macro with which the
819 interpreter was compiled.
820
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000821- Fixed bug #470582: sre module would return a tuple (None, 'a', 'ab')
822 when applying the regular expression '^((a)c)?(ab)$' on 'ab'. It now
823 returns (None, None, 'ab'), as expected. Also fixed handling of
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +0000824 lastindex/lastgroup match attributes in similar cases. For example,
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000825 when running the expression r'(a)(b)?b' over 'ab', lastindex must be
826 1, not 2.
827
Gustavo Niemeyerc523b042002-11-07 03:28:56 +0000828- Fixed bug #581080: sre scanner was not checking the buffer limit
829 before increasing the current pointer. This was creating an infinite
830 loop in the search function, once the pointer exceeded the buffer
831 limit.
832
Thomas Heller95cb7e42002-11-07 16:23:55 +0000833- The os.fdopen function now enforces a file mode starting with the
834 letter 'r', 'w' or 'a', otherwise a ValueError is raised. This fixes
835 bug #623464.
836
Greg Ward6c58d462003-01-03 18:02:15 +0000837- The linuxaudiodev module is now deprecated; it is being replaced by
838 ossaudiodev. The interface has been extended to cover a lot more of
839 OSS (see www.opensound.com), including most DSP ioctls and the
840 OSS mixer API. Documentation forthcoming in 2.3a2.
841
Tim Petersaf8446f2001-12-21 21:36:50 +0000842Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000843-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000844
Guido van Rossum747f8062003-01-03 16:33:49 +0000845- imaplib.py now supports SSL (Tino Lange and Piers Lauder).
846
Just van Rossum5e156ad2002-12-31 16:38:01 +0000847- Freeze's modulefinder.py has been moved to the standard library;
848 slightly improved so it will issue less false missing submodule
849 reports (see sf path #643711 for details). Documentation will follow
850 with Python 2.3a2.
851
Martin v. Löwis96a60e42002-12-31 13:11:54 +0000852- os.path exposes getctime.
853
Raymond Hettingeraf72d522002-12-29 20:14:11 +0000854- unittest.py now has two additional methods called assertAlmostEqual()
855 and failIfAlmostEqual(). They implement an approximate comparision
856 by rounding the difference between the two arguments and comparing
857 the result to zero. Approximate comparision is essential for
858 unit tests of floating point results.
859
Raymond Hettingere11b5102002-12-25 16:37:19 +0000860- calendar.py now depends on the new datetime module rather than
861 the time module. As a result, the range of allowable dates
862 has been increased.
863
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000864- pdb has a new 'j(ump)' command to select the next line to be
865 executed.
866
Thomas Heller1b3b49d2002-12-12 19:13:44 +0000867- The distutils created windows installers now can run a
868 postinstallation script.
869
Martin v. Löwis4581cfa2002-11-22 08:23:09 +0000870- doctest.testmod can now be called without argument, which means to
871 test the current module.
872
Martin v. Löwisf86e8ef2002-11-22 08:08:44 +0000873- When cancelling a server that implemented threading with a keyboard
874 interrupt, the server would shut down but not terminate (waiting on
875 client threads). A new member variable, daemon_threads, was added to
876 the ThreadingMixIn class in SocketServer.py to make it explicit that
877 this behavior needs to be controlled.
878
Guido van Rossum545c2502002-11-15 13:19:58 +0000879- A new module, optparse, provides a fancy alternative to getopt for
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000880 command line parsing. It is a slightly modified version of Greg
Guido van Rossum545c2502002-11-15 13:19:58 +0000881 Ward's Optik package.
882
Raymond Hettinger79947162002-11-15 06:46:14 +0000883- UserDict.py now defines a DictMixin class which defines all dictionary
884 methods for classes that already have a minimum mapping interface.
885 This greatly simplifies writing classes that need to be substitutable
886 for dictionaries (such as the shelve module).
887
888- shelve.py now subclasses from UserDict.DictMixin. Now shelve supports
889 all dictionary methods. This eases the transition to persistent
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000890 storage for scripts originally written with dictionaries in mind.
Raymond Hettinger79947162002-11-15 06:46:14 +0000891
Skip Montanaro3bf99e32002-12-08 18:36:24 +0000892- shelve.open and the various classes in shelve.py now accept an optional
893 binary flag, which defaults to False. If True, the values stored in the
894 shelf are binary pickles.
895
Guido van Rossumfda06742002-11-13 16:29:18 +0000896- A new package, logging, implements the logging API defined by PEP
897 282. The code is written by Vinay Sajip.
898
Walter Dörwald4dbf1922002-11-06 16:53:44 +0000899- StreamReader, StreamReaderWriter and StreamRecoder in the codecs
900 modules are iterators now.
901
Tim Peters9288f952002-11-05 20:38:55 +0000902- gzip.py now handles files exceeding 2GB. Files over 4GB also work
903 now (provided the OS supports it, and Python is configured with large
904 file support), but in that case the underlying gzip file format can
905 record only the least-significant 32 bits of the file size, so that
906 some tools working with gzipped files may report an incorrect file
907 size.
Tim Petersfb0ea522002-11-04 19:50:11 +0000908
Martin v. Löwis74b51ac2002-10-26 14:50:45 +0000909- xml.sax.saxutils.unescape has been added, to replace entity references
910 with their entity value.
911
Martin v. Löwis77ac4292002-10-15 15:11:13 +0000912- Queue.Queue.{put,get} now support an optional timeout argument.
913
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000914- Various features of Tk 8.4 are exposed in Tkinter.py. The multiple
915 option of tkFileDialog is exposed as function askopenfile{,name}s.
Martin v. Löwis2ec36272002-10-13 10:22:08 +0000916
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000917- Various configure methods of Tkinter have been stream-lined, so that
918 tag_configure, image_configure, window_configure now return a
Tim Petersfb0ea522002-11-04 19:50:11 +0000919 dictionary when invoked with no argument.
Martin v. Löwis6ce13152002-10-10 14:36:13 +0000920
Guido van Rossum2b492b62002-10-09 21:40:48 +0000921- Importing the readline module now no longer has the side effect of
922 calling setlocale(LC_CTYPE, ""). The initial "C" locale, or
923 whatever locale is explicitly set by the user, is preserved. If you
924 want repr() of 8-bit strings in your preferred encoding to preserve
925 all printable characters of that encoding, you have to add the
926 following code to your $PYTHONSTARTUP file or to your application's
927 main():
928
929 import locale
930 locale.setlocale(locale.LC_CTYPE, "")
931
Martin v. Löwise9ce0b02002-10-07 13:23:24 +0000932- shutil.move was added. shutil.copytree now reports errors as an
933 exception at the end, instead of printing error messages.
934
Marc-André Lemburg97047e22002-10-04 11:55:21 +0000935- Encoding name normalization was generalized to not only
936 replace hyphens with underscores, but also all other non-alphanumeric
937 characters (with the exception of the dot which is used for Python
938 package names during lookup). The aliases.py mapping was updated
939 to the new standard.
940
Walter Dörwald5ccaf8f2002-09-06 16:15:58 +0000941- mimetypes has two new functions: guess_all_extensions() which
942 returns a list of all known extensions for a mime type, and
943 add_type() which adds one mapping between a mime type and
944 an extension to the database.
945
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000946- New module: sets, defines the class Set that implements a mutable
947 set type using the keys of a dict to represent the set. There's
948 also a class ImmutableSet which is useful when you need sets of sets
949 or when you need to use sets as dict keys, and a class BaseSet which
Raymond Hettingeref8b9c62002-12-09 08:56:06 +0000950 is the base class of the two.
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000951
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000952- Added random.sample(population,k) for random sampling without replacement.
Tim Petersb9099c32002-11-12 22:08:10 +0000953 Returns a k length list of unique elements chosen from the population.
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000954
Tim Peters012c0a32002-08-16 03:40:07 +0000955- random.randrange(-sys.maxint-1, sys.maxint) no longer raises
956 OverflowError. That is, it now accepts any combination of 'start'
957 and 'stop' arguments so long as each is in the range of Python's
958 bounded integers.
959
Raymond Hettinger40f62172002-12-29 23:03:38 +0000960- Thanks to Raymond Hettinger, random.random() now uses a new core
961 generator. The Mersenne Twister algorithm is implemented in C,
962 threadsafe, faster than the previous generator, has an astronomically
963 large period (2**19937-1), creates random floats to full 53-bit
964 precision, and may be the most widely tested random number generator
965 in existence.
966
967 The random.jumpahead(n) method has different semantics for the new
968 generator. Instead of jumping n steps ahead, it uses n and the
969 existing state to create a new state. This means that jumpahead()
970 continues to support multi-threaded code needing generators of
971 non-overlapping sequences. However, it will break code which relies
972 on jumpahead moving a specific number of steps forward.
973
974 The attributes random.whseed and random.__whseed have no meaning for
975 the new generator. Code using these attributes should switch to a
976 new class, random.WichmannHill which is provided for backward
977 compatibility and to make an alternate generator available.
978
Guido van Rossum4a57c332002-08-02 18:05:20 +0000979- New "algorithms" module: heapq, implements a heap queue. Thanks to
980 Kevin O'Connor for the code and François Pinard for an entertaining
981 write-up explaining the theory and practical uses of heaps.
982
Marc-André Lemburg58e2ff22002-07-12 14:40:04 +0000983- New encoding for the Palm OS character set: palmos.
984
Tim Peters943382c2002-07-07 03:59:34 +0000985- binascii.crc32() and the zipfile module had problems on some 64-bit
986 platforms. These have been fixed. On a platform with 8-byte C longs,
987 crc32() now returns a signed-extended 4-byte result, so that its value
988 as a Python int is equal to the value computed a 32-bit platform.
989
Martin v. Löwis7d650ca2002-06-30 15:05:00 +0000990- xml.dom.minidom.toxml and toprettyxml now take an optional encoding
991 argument.
992
Guido van Rossum9f7549b2002-06-10 21:39:42 +0000993- Some fixes in the copy module: when an object is copied through its
994 __reduce__ method, there was no check for a __setstate__ method on
995 the result [SF patch 565085]; deepcopy should treat instances of
996 custom metaclasses the same way it treats instances of type 'type'
997 [SF patch 560794].
998
Guido van Rossum5033c8e2002-06-07 12:40:52 +0000999- Sockets now support timeout mode. After s.settimeout(T), where T is
1000 a float expressing seconds, subsequent operations raise an exception
1001 if they cannot be completed within T seconds. To disable timeout
Guido van Rossum79f0a102002-07-23 03:32:08 +00001002 mode, use s.settimeout(None). There's also a module function,
1003 socket.setdefaulttimeout(T), which sets the default for all sockets
1004 created henceforth.
Guido van Rossum5033c8e2002-06-07 12:40:52 +00001005
1006- getopt.gnu_getopt was added. This supports GNU-style option
1007 processing, where options can be mixed with non-option arguments.
Martin v. Löwis446a25f2002-06-06 10:58:36 +00001008
Michael W. Hudsonb0dc1a32002-06-04 18:27:35 +00001009- Stop using strings for exceptions. String objects used for
1010 exceptions are now classes deriving from Exception. The objects
1011 changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
1012 tabnanny.NannyNag, and xdrlib.Error.
Neal Norwitzb5b5a262002-06-04 17:14:07 +00001013
Walter Dörwald474458d2002-06-04 15:16:29 +00001014- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
1015 BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
1016 Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
1017 big endian systems were added to the codecs module. The old names
1018 BOM32_* and BOM64_* were off by a factor of 2.
1019
Guido van Rossumf9257822002-06-18 20:43:18 +00001020- Added conversion functions math.degrees() and math.radians().
Raymond Hettinger87f59ee2002-05-13 04:17:32 +00001021
Raymond Hettinger866964c2002-12-14 19:51:34 +00001022- math.log() now takes an optional argument: math.log(x[, base]).
1023
Raymond Hettinger9b1df1d2002-05-12 06:07:21 +00001024- ftplib.retrlines() now tests for callback is None rather than testing
1025 for False. Was causing an error when given a callback object which
1026 was callable but also returned len() as zero. The change may
1027 create new breakage if the caller relied on the undocumented behavior
1028 and called with callback set to [] or some other False value not
1029 identical to None.
1030
Tim Peters46c04e12002-05-05 20:40:00 +00001031- random.gauss() uses a piece of hidden state used by nothing else,
1032 and the .seed() and .whseed() methods failed to reset it. In other
1033 words, setting the seed didn't completely determine the sequence of
1034 results produced by random.gauss(). It does now. Programs repeatedly
1035 mixing calls to a seed method with calls to gauss() may see different
1036 results now.
1037
Fred Drake7f781c92002-05-01 20:33:53 +00001038- The pickle.Pickler class grew a clear_memo() method to mimic that
1039 provided by cPickle.Pickler.
1040
Tim Peters81b92512002-04-29 01:37:32 +00001041- difflib's SequenceMatcher class now does a dynamic analysis of
1042 which elements are so frequent as to constitute noise. For
1043 comparing files as sequences of lines, this generally works better
1044 than the IS_LINE_JUNK function, and function ndiff's linejunk
1045 argument defaults to None now as a result. A happy benefit is
1046 that SequenceMatcher may run much faster now when applied
1047 to large files with many duplicate lines (for example, C program
1048 text with lots of repeated "}" and "return NULL;" lines).
1049
Guido van Rossum256705b2002-04-23 13:29:43 +00001050- New Text.dump() method in Tkinter module.
1051
Marc-André Lemburg1ec71ea2002-04-17 20:33:40 +00001052- New distutils commands for building packagers were added to
1053 support pkgtool on Solaris and swinstall on HP-UX.
1054
1055- distutils now has a new abstract binary packager base class
1056 command/bdist_packager, which simplifies writing packagers.
1057 This will hopefully provide the missing bits to encourage
1058 people to submit more packagers, e.g. for Debian, FreeBSD
1059 and other systems.
1060
Guido van Rossumf9257822002-06-18 20:43:18 +00001061- The UTF-16, -LE and -BE stream readers now raise a
1062 NotImplementedError for all calls to .readline(). Previously, they
1063 used to just produce garbage or fail with an encoding error --
1064 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 +00001065 work well with these.
1066
Martin v. Löwis5c137c22002-03-18 12:44:08 +00001067- compileall now supports quiet operation.
1068
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001069- The BaseHTTPServer now implements optional HTTP/1.1 persistent
Martin v. Löwis587c98c2002-03-17 18:37:22 +00001070 connections.
1071
Marc-André Lemburga5d2b4c2002-02-16 18:23:30 +00001072- socket module: the SSL support was broken out of the main
1073 _socket module C helper and placed into a new _ssl helper
1074 which now gets imported by socket.py if available and working.
1075
Marc-André Lemburg37aa5802002-02-10 21:42:47 +00001076- encodings package: added aliases for all supported IANA character
1077 sets
1078
Guido van Rossum606fe4e2001-12-28 20:57:14 +00001079- ftplib: to safeguard the user's privacy, anonymous login will use
1080 "anonymous@" as default password, rather than the real user and host
1081 name.
1082
Fred Drake36736122002-01-10 13:50:31 +00001083- webbrowser: tightened up the command passed to os.system() so that
1084 arbitrary shell code can't be executed because a bogus URL was
1085 passed in.
1086
Tim Peters11bd9942002-02-01 00:52:29 +00001087- gettext.translation has an optional fallback argument, and
Martin v. Löwisa55ffae2002-01-11 06:58:49 +00001088 gettext.find an optional all argument. Translations will now fallback
Martin v. Löwisd8996052002-11-21 21:45:32 +00001089 on a per-message basis. The module supports plural forms, by means
1090 of gettext.[d]ngettext and Translation.[u]ngettext.
Martin v. Löwis1be64192002-01-11 06:33:28 +00001091
Martin v. Löwis9668b932002-01-12 11:27:42 +00001092- distutils bdist commands now offer a --skip-build option.
1093
Walter Dörwaldb25c2b02002-03-21 10:38:40 +00001094- warnings.warn now accepts a Warning instance as first argument.
1095
Fred Drakefed7e852002-04-04 19:36:15 +00001096- The xml.sax.expatreader.ExpatParser class will no longer create
1097 circular references by using itself as the locator that gets passed
1098 to the content handler implementation. [SF bug #535474]
1099
Barry Warsaw47f3e2c2002-05-20 00:14:24 +00001100- The email.Parser.Parser class now properly parses strings regardless
1101 of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
1102 or CRLF). Also, the Header class's constructor default arguments
1103 has changed slightly so that an explicit maxlinelen value is always
Barry Warsaw497e5c42002-12-30 19:27:08 +00001104 honored, and so unicode conversion error handling can be specified.
Barry Warsaw47f3e2c2002-05-20 00:14:24 +00001105
David Goodgerf349e262003-01-03 03:30:21 +00001106- distutils' build_ext command now links C++ extensions with the C++
Gustavo Niemeyerf8ca8362002-11-05 16:50:05 +00001107 compiler available in the Makefile or CXX environment variable, if
David Goodgerf349e262003-01-03 03:30:21 +00001108 running under \*nix.
Gustavo Niemeyerf8ca8362002-11-05 16:50:05 +00001109
1110- New module bz2: provides a comprehensive interface for the bz2 compression
1111 library. It implements a complete file interface, one-shot (de)compression
1112 functions, and types for sequential (de)compression.
1113
David Goodgerf349e262003-01-03 03:30:21 +00001114- New pdb command 'pp' which is like 'p' except that it pretty-prints
Barry Warsaw5d8d6182002-11-05 22:41:33 +00001115 the value of its expression argument.
1116
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +00001117- Now bdist_rpm distutils command understands a verify_script option in
1118 the config file, including the contents of the referred filename in
1119 the "%verifyscript" section of the rpm spec file.
1120
Gustavo Niemeyer1456fde2002-11-25 17:25:04 +00001121- Fixed bug #495695: webbrowser module would run graphic browsers in a
1122 unix environment even if DISPLAY was not set. Also, support for
1123 skipstone browser was included.
1124
Gustavo Niemeyerd5ae01a2002-12-16 13:11:57 +00001125- Fixed bug #636769: rexec would run unallowed code if subclasses of
1126 strings were used as parameters for certain functions.
1127
Tim Petersaf8446f2001-12-21 21:36:50 +00001128Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001129-----------
Tim Petersaf8446f2001-12-21 21:36:50 +00001130
Martin v. Löwis0d1fdea2002-11-22 08:36:54 +00001131- pygettext.py now supports globbing on Windows, and accepts module
1132 names in addition to accepting file names.
1133
Guido van Rossum923e4ef2002-09-17 20:58:59 +00001134- The SGI demos (Demo/sgi) have been removed. Nobody thought they
1135 were interesting any more. (The SGI library modules and extensions
1136 are still there; it is believed that at least some of these are
1137 still used and useful.)
1138
Fred Drake40813b12002-08-05 15:24:19 +00001139- IDLE supports the new encoding declarations (PEP 263); it can also
1140 deal with legacy 8-bit files if they use the locale's encoding. It
1141 allows non-ASCII strings in the interactive shell and executes them
1142 in the locale's encoding.
Martin v. Löwis98ce7b72002-08-05 15:11:26 +00001143
Marc-André Lemburg46260092002-04-04 16:17:11 +00001144- freeze.py now produces binaries which can import shared modules,
1145 unlike before when this failed due to missing symbol exports in
1146 the generated binary.
1147
Tim Petersaf8446f2001-12-21 21:36:50 +00001148Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001149-----
Tim Petersaf8446f2001-12-21 21:36:50 +00001150
Martin v. Löwisdc461752002-11-06 21:59:33 +00001151- On Unix, IDLE is now installed automatically.
1152
Guido van Rossum6b3db552002-09-25 15:02:44 +00001153- The fpectl module is not built by default; it's dangerous or useless
1154 except in the hands of experts.
1155
Tim Petersf47630f2002-08-01 02:34:51 +00001156- The public Python C API will generally be declared using PyAPI_FUNC
Guido van Rossum6b3db552002-09-25 15:02:44 +00001157 and PyAPI_DATA macros, while Python extension module init functions
1158 will be declared with PyMODINIT_FUNC. DL_EXPORT/DL_IMPORT macros
1159 are deprecated.
Neal Norwitz1389f3e2002-07-22 13:21:10 +00001160
Tim Petersc6a3ff62002-07-08 22:11:52 +00001161- A bug was fixed that could cause COUNT_ALLOCS builds to segfault, or
1162 get into infinite loops, when a new-style class got garbage-collected.
1163 Unfortunately, to avoid this, the way COUNT_ALLOCS works requires
1164 that new-style classes be immortal in COUNT_ALLOCS builds. Note that
1165 COUNT_ALLOCS is not enabled by default, in either release or debug
1166 builds, and that new-style classes are immortal only in COUNT_ALLOCS
1167 builds.
1168
Tim Peters943382c2002-07-07 03:59:34 +00001169- Compiling out the cyclic garbage collector is no longer an option.
1170 The old symbol WITH_CYCLE_GC is now ignored, and Python.h arranges
1171 that it's always defined (for the benefit of any extension modules
1172 that may be conditionalizing on it). A bonus is that any extension
1173 type participating in cyclic gc can choose to participate in the
1174 Py_TRASHCAN mechanism now too; in the absence of cyclic gc, this used
1175 to require editing the core to teach the trashcan mechanism about the
1176 new type.
1177
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +00001178- According to Annex F of the current C standard,
Tim Peters1de41bf2002-07-03 03:31:20 +00001179
1180 The Standard C macro HUGE_VAL and its float and long double analogs,
1181 HUGE_VALF and HUGE_VALL, expand to expressions whose values are
1182 positive infinities.
1183
1184 Python only uses the double HUGE_VAL, and only to #define its own symbol
1185 Py_HUGE_VAL. Some platforms have incorrect definitions for HUGE_VAL.
1186 pyport.h used to try to worm around that, but the workarounds triggered
1187 other bugs on other platforms, so we gave up. If your platform defines
1188 HUGE_VAL incorrectly, you'll need to #define Py_HUGE_VAL to something
1189 that works on your platform. The only instance of this I'm sure about
1190 is on an unknown subset of Cray systems, described here:
1191
1192 http://www.cray.com/swpubs/manuals/SN-2194_2.0/html-SN-2194_2.0/x3138.htm
1193
1194 Presumably 2.3a1 breaks such systems. If anyone uses such a system, help!
1195
Martin v. Löwisa3fb4f72002-06-09 13:33:54 +00001196- The configure option --without-doc-strings can be used to remove the
1197 doc strings from the builtin functions and modules; this reduces the
1198 size of the executable.
1199
Guido van Rossumadd88062002-08-15 14:01:14 +00001200- The universal newlines option (PEP 278) is on by default. On Unix
1201 it can be disabled by passing --without-universal-newlines to the
1202 configure script. On other platforms, remove
1203 WITH_UNIVERSAL_NEWLINES from pyconfig.h.
Tim Peters639295f2002-04-21 07:30:30 +00001204
Martin v. Löwis1142de32002-03-29 16:28:31 +00001205- On Unix, a shared libpython2.3.so can be created with --enable-shared.
1206
Tim Peters8deda702002-03-30 10:06:07 +00001207- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
1208 preprocessor symbols were eliminated. The internal decisions they
1209 controlled stopped being experimental long ago.
Tim Peters1f7df352002-03-29 03:29:08 +00001210
Fred Drake7d28b732002-05-02 21:17:00 +00001211- The tools used to build the documentation now work under Cygwin as
1212 well as Unix.
1213
Skip Montanaro57454e52002-06-14 20:30:31 +00001214- The bsddb and dbm module builds have been changed to try and avoid version
1215 skew problems and disable linkage with Berkeley DB 1.85 unless the
1216 installer knows what s/he's doing. See the section on building these
1217 modules in the README file for details.
1218
Tim Petersaf8446f2001-12-21 21:36:50 +00001219C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001220-----
Tim Petersaf8446f2001-12-21 21:36:50 +00001221
Neil Schemenauer6c194762002-11-18 16:19:39 +00001222- PyNumber_Check() now returns true for string and unicode objects.
1223 This is a result of these types having a partially defined
Guido van Rossum1d267402002-11-18 16:27:16 +00001224 tp_as_number slot. (This is not a feature, but an indication that
Walter Dörwalda1a61f92002-11-19 21:20:25 +00001225 PyNumber_Check() is not very useful to determine numeric behavior.
Guido van Rossum1d267402002-11-18 16:27:16 +00001226 It may be deprecated.)
Neil Schemenauer6c194762002-11-18 16:19:39 +00001227
Guido van Rossum45ec02a2002-08-19 21:43:18 +00001228- The string object's layout has changed: the pointer member
1229 ob_sinterned has been replaced by an int member ob_sstate. On some
1230 platforms (e.g. most 64-bit systems) this may change the offset of
1231 the ob_sval member, so as a precaution the API_VERSION has been
1232 incremented. The apparently unused feature of "indirect interned
1233 strings", supported by the ob_sinterned member, is gone. Interned
1234 strings are now usually mortal; theres a new API,
1235 PyString_InternImmortal() that creates immortal interned strings.
1236 (The ob_sstate member can only take three values; however, while
1237 making it a char saves a few bytes per string object on average, in
1238 it also slowed things down a bit because ob_sval was no longer
1239 aligned.)
1240
Guido van Rossumfdb86482002-08-14 21:20:32 +00001241- The Py_InitModule*() functions now accept NULL for the 'methods'
1242 argument. Modules without global functions are becoming more common
1243 now that factories can be types rather than functions.
1244
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +00001245- New C API PyUnicode_FromOrdinal() which exposes unichr() at C
1246 level.
1247
Thomas Heller085358a2002-07-29 14:27:41 +00001248- New functions PyErr_SetExcFromWindowsErr() and
1249 PyErr_SetExcFromWindowsErrWithFilename(). Similar to
1250 PyErr_SetFromWindowsErrWithFilename() and
1251 PyErr_SetFromWindowsErr(), but they allow to specify
1252 the exception type to raise. Available on Windows.
1253
Tim Peters7c321a82002-07-09 02:57:01 +00001254- Py_FatalError() is now declared as taking a const char* argument. It
1255 was previously declared without const. This should not affect working
1256 code.
1257
Martin v. Löwis01f94bd2002-05-08 08:44:21 +00001258- Added new macro PySequence_ITEM(o, i) that directly calls
1259 sq_item without rechecking that o is a sequence and without
1260 adjusting for negative indices.
1261
Fred Draked0ba6362002-05-02 21:28:26 +00001262- PyRange_New() now raises ValueError if the fourth argument is not 1.
1263 This is part of the removal of deprecated features of the xrange
1264 object.
1265
Guido van Rossum517c7d42002-04-26 02:49:14 +00001266- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
1267 coercion if both arguments have the same type but this type has the
1268 CHECKTYPES flag set. This is to better support proxies.
1269
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00001270- The type of tp_free has been changed from "``void (*)(PyObject *)``" to
1271 "``void (*)(void *)``".
Neil Schemenauer9344b142002-04-12 23:00:08 +00001272
1273- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
1274
Guido van Rossum0986d822002-04-08 01:38:42 +00001275- A type can now inherit its metatype from its base type. Previously,
1276 when PyType_Ready() was called, if ob_type was found to be NULL, it
1277 was always set to &PyType_Type; now it is set to base->ob_type,
1278 where base is tp_base, defaulting to &PyObject_Type.
1279
1280- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
1281
Neil Schemenauerc9abc1d2002-05-08 14:14:41 +00001282- The PyCore_* family of APIs have been removed.
Neil Schemenauer9d50d132002-03-22 17:06:59 +00001283
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001284- The "u#" parser marker will now pass through Unicode objects as-is
Marc-André Lemburg3e3eacb2002-01-09 16:21:27 +00001285 without going through the buffer API.
1286
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001287- The enumerators of cmp_op have been renamed to use the prefix ``PyCmp_``.
Martin v. Löwis7198a522002-01-01 19:59:11 +00001288
Tim Peters10a3bb52001-12-25 19:07:38 +00001289- An old #define of ANY as void has been removed from pyport.h. This
1290 hasn't been used since Python's pre-ANSI days, and the #define has
1291 been marked as obsolete since then. SF bug 495548 says it created
1292 conflicts with other packages, so keeping it around wasn't harmless.
1293
Tim Petersaf8446f2001-12-21 21:36:50 +00001294- Because Python's magic number scheme broke on January 1st, we decided
1295 to stop Python development. Thanks for all the fish!
1296
Tim Petersfb05db22002-03-11 00:24:00 +00001297- Some of us don't like fish, so we changed Python's magic number
Marc-André Lemburge92e0a92002-02-09 11:28:43 +00001298 scheme to a new one. See Python/import.c for details.
1299
Tim Petersaf8446f2001-12-21 21:36:50 +00001300New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001301-------------
Tim Petersaf8446f2001-12-21 21:36:50 +00001302
Martin v. Löwis79acb9e2002-12-06 12:48:53 +00001303- OpenVMS is now supported.
1304
Martin v. Löwisf90ae202002-06-11 06:22:31 +00001305- AtheOS is now supported.
1306
Andrew MacIntyre161ad0e2002-08-04 07:25:58 +00001307- the EMX runtime environment on OS/2 is now supported.
1308
Martin v. Löwisa6e97582002-01-01 18:41:33 +00001309- GNU/Hurd is now supported.
1310
Tim Petersaf8446f2001-12-21 21:36:50 +00001311Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001312-----
1313
Fred Drake4dd0f7e2002-11-26 21:44:56 +00001314- The regrtest.py script's -u option now provides a way to say "allow
1315 all resources except this one." For example, to allow everything
1316 except bsddb, give the option '-uall,-bsddb'.
Tim Petersaf8446f2001-12-21 21:36:50 +00001317
1318Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001319-------
Tim Petersaf8446f2001-12-21 21:36:50 +00001320
Tim Peters19cf4ee2002-11-23 03:49:08 +00001321- The Windows distribution now ships with version 4.0.14 of the
1322 Sleepycat Berkeley database library. This should be a huge
1323 improvement over the previous Berkeley DB 1.85, which had many
1324 bugs.
1325 XXX What are the licensing issues here?
Tim Peters84c7a3f2002-11-23 18:48:06 +00001326 XXX If a user has a database created with a previous verion of
1327 XXX Python, what must they do to convert it?
1328 XXX I'm still not sure how to link this thing (see PCbuild/readme.txt).
Tim Peters19cf4ee2002-11-23 03:49:08 +00001329 XXX The version # is likely to change before 2.3a1.
Tim Peterse820cb62002-12-16 20:57:22 +00001330
1331- The Windows distribution now ships with a Secure Sockets Library (SLL)
Mark Hammondc3de0082002-12-03 06:16:08 +00001332 module (_ssl.pyd)
Tim Peters19cf4ee2002-11-23 03:49:08 +00001333
Tim Peters857fb4c2002-11-14 23:31:58 +00001334- The Windows distribution now ships with Tcl/Tk version 8.4.1 (it
1335 previously shipped with Tcl/Tk 8.3.2).
1336
Tim Peters37dfb012002-11-11 19:51:33 +00001337- When Python is built under a Microsoft compiler, sys.version now
1338 includes the compiler version number (_MSC_VER). For example, under
1339 MSVC 6, sys.version constains the substring "MSC v.1200 ". 1200 is
1340 the value of _MSC_VER under MSVC 6.
1341
Tim Peters08e72952002-04-16 20:48:01 +00001342- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
1343 of that has been fixed in the installer (disabled Wise's "delete in-
1344 use files" uninstall option).
1345
Guido van Rossum181e41a2002-04-06 00:23:25 +00001346- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
1347
Tim Peters33187922002-04-04 20:02:04 +00001348- The installer now installs Start menu shortcuts under (the local
1349 equivalent of) "All Users" when doing an Admin install.
1350
Tim Petersfb05db22002-03-11 00:24:00 +00001351- file.truncate([newsize]) now works on Windows for all newsize values.
1352 It used to fail if newsize didn't fit in 32 bits, reflecting a
1353 limitation of MS _chsize (which is no longer used).
1354
Tim Petersab034fa2002-02-01 11:27:43 +00001355- os.waitpid() is now implemented for Windows, and can be used to block
1356 until a specified process exits. This is similar to, but not exactly
1357 the same as, os.waitpid() on POSIX systems. If you're waiting for
1358 a specific process whose pid was obtained from one of the spawn()
1359 functions, the same Python os.waitpid() code works across platforms.
Tim Peters33187922002-04-04 20:02:04 +00001360 See the docs for details. The docs were changed to clarify that
1361 spawn functions return, and waitpid requires, a process handle on
1362 Windows (not the same thing as a Windows process id).
Tim Petersab034fa2002-02-01 11:27:43 +00001363
Tim Peters11bd9942002-02-01 00:52:29 +00001364- New tempfile.TemporaryFile implementation for Windows: this doesn't
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001365 need a TemporaryFileWrapper wrapper anymore, and should be immune
Tim Peters11bd9942002-02-01 00:52:29 +00001366 to a nasty problem: before 2.3, if you got a temp file on Windows, it
1367 got wrapped in an object whose close() method first closed the
1368 underlying file, then deleted the file. This usually worked fine.
1369 However, the spawn family of functions on Windows create (at a low C
1370 level) the same set of open files in the spawned process Q as were
1371 open in the spawning process P. If a temp file f was among them, then
1372 doing f.close() in P first closed P's C-level file handle on f, but Q's
1373 C-level file handle on f remained open, so the attempt in P to delete f
1374 blew up with a "Permission denied" error (Windows doesn't allow
1375 deleting open files). This was surprising, subtle, and difficult to
1376 work around.
1377
1378- The os module now exports all the symbolic constants usable with the
1379 low-level os.open() on Windows: the new constants in 2.3 are
1380 O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
1381 The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
1382 O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
1383 to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
1384 (so specify both if you want both; note that neither is useful unless
1385 specified with O_CREAT too).
1386
Tim Petersaf8446f2001-12-21 21:36:50 +00001387Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001388----
1389
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001390- Mac/Relnotes is gone, the release notes are now here.
Tim Petersaf8446f2001-12-21 21:36:50 +00001391
Just van Rossume1ebd802003-02-10 10:06:18 +00001392- Python (the OSX-only, unix-based version, not the OS9-compatible CFM
1393 version) now fully supports unicode strings as arguments to various file
1394 system calls, eg. open(), file(), os.stat() and os.listdir().
1395
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001396- The current naming convention for Python on the Macintosh is that MacPython
1397 refers to the unix-based OSX-only version, and MacPython-OS9 refers to the
1398 CFM-based version that runs on both OS9 and OSX.
1399
1400- All MacPython-OS9 functionality is now available in an OSX unix build,
1401 including the Carbon modules, the IDE, OSA support, etc. A lot of this
1402 will only work correctly in a framework build, though, because you cannot
1403 talk to the window manager unless your application is run from a .app
1404 bundle. There is a command line tool "pythonw" that runs your script
1405 with an interpreter living in such a .app bundle, this interpreter should
1406 be used to run any Python script using the window manager (including
1407 Tkinter or wxPython scripts).
Tim Petersbbc5d162003-01-02 16:02:27 +00001408
Jack Jansen8bb80db2002-12-30 22:42:43 +00001409- Most of Mac/Lib has moved to Lib/plat-mac, which is again used both in
1410 MacPython-OSX and MacPython-OS9. The only modules remaining in Mac/Lib
1411 are specifically for MacPython-OS9 (CFM support, preference resources, etc).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001412
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001413- A new utility PythonLauncher will start a Python interpreter when a .py or
1414 .pyw script is double-clicked in the Finder. By default .py scripts are
1415 run with a normal Python interpreter in a Terminal window and .pyw
1416 files are run with a window-aware pythonw interpreter without a Terminal
1417 window, but all this can be customized.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001418
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001419- MacPython-OS9 is now Carbon-only, so it runs on Mac OS 9 or Mac OS X and
1420 possibly on Mac OS 8.6 with the right CarbonLib installed, but not on earlier
1421 releases.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001422
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001423- Many tools such as BuildApplet.py and gensuitemodule.py now support a command
1424 line interface too.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001425
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001426- All the Carbon classes are now PEP253 compliant, meaning that you can
1427 subclass them from Python. Most of the attributes have gone, you should
1428 now use the accessor function call API, which is also what Apple's
1429 documentation uses. Some attributes such as grafport.visRgn are still
1430 available for convenience.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001431
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001432- New Carbon modules File (implementing the APIs in Files.h and Aliases.h)
1433 and Folder (APIs from Folders.h). The old macfs builtin module is
1434 gone, and replaced by a Python wrapper around the new modules.
1435
1436- Pathname handling should now be fully consistent: MacPython-OSX always uses
1437 unix pathnames and MacPython-OS9 always uses colon-separated Mac pathnames
1438 (also when running on Mac OS X).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001439
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001440- New Carbon modules Help and AH give access to the Carbon Help Manager.
1441 There are hooks in the IDE to allow accessing the Python documentation
1442 (and Apple's Carbon and Cocoa documentation) through the Help Viewer.
1443 See Mac/OSX/README for converting the Python documentation to a
1444 Help Viewer comaptible form and installing it.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001445
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001446- OSA support has been redesigned and the generated Python classes now
1447 mirror the inheritance defined by the underlying OSA classes.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001448
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001449- MacPython no longer maps both \r and \n to \n on input for any text file.
1450 This feature has been replaced by universal newline support (PEP278).
Tim Peters0bf60bd2003-01-08 20:40:01 +00001451
Jack Jansen05d284b2003-01-08 16:29:17 +00001452- The default encoding for Python sourcefiles in MacPython-OS9 is no longer
1453 mac-roman (or whatever your local Mac encoding was but "ascii", like on
1454 other platforms. If you really need sourcefiles with Mac characters in them
1455 you can change this in site.py.
Tim Petersaf8446f2001-12-21 21:36:50 +00001456
Tim Peters909c0912001-12-14 23:16:18 +00001457What's New in Python 2.2 final?
Tim Peters909c0912001-12-14 23:16:18 +00001458===============================
1459
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001460*Release date: 21-Dec-2001*
1461
Tim Peters909c0912001-12-14 23:16:18 +00001462Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001463--------------------------------------------
Tim Peters909c0912001-12-14 23:16:18 +00001464
Barry Warsaw52acb492001-12-21 20:04:22 +00001465- pickle.py, cPickle: allow pickling instances of new-style classes
1466 with a custom metaclass.
1467
Tim Peters909c0912001-12-14 23:16:18 +00001468Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001469-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001470
Barry Warsaw52acb492001-12-21 20:04:22 +00001471- weakref proxy object: when comparing, unwrap both arguments if both
1472 are proxies.
1473
Tim Peters909c0912001-12-14 23:16:18 +00001474Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001475-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001476
Barry Warsaw52acb492001-12-21 20:04:22 +00001477- binascii.b2a_base64(): fix a potential buffer overrun when encoding
1478 very short strings.
1479
1480- cPickle: the obscure "fast" mode was suspected of causing stack
1481 overflows on the Mac. Hopefully fixed this by setting the recursion
1482 limit much smaller. If the limit is too low (it only affects
1483 performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
1484 when compiling cPickle.c (or in pyconfig.h).
1485
Tim Peters909c0912001-12-14 23:16:18 +00001486Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001487-------
Tim Peters909c0912001-12-14 23:16:18 +00001488
Barry Warsaw52acb492001-12-21 20:04:22 +00001489- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
1490 close or delete time).
1491
1492- rfc822.py: fixed a bug where the address '<>' was converted to None
1493 instead of an empty string (also fixes the email.Utils module).
1494
1495- xmlrpclib.py: version 1.0.0; uses precision for doubles.
1496
1497- test suite: the pickle and cPickle tests were not executing any code
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001498 when run from the standard regression test.
Barry Warsaw52acb492001-12-21 20:04:22 +00001499
Tim Peters909c0912001-12-14 23:16:18 +00001500Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001501-----------
Tim Peters909c0912001-12-14 23:16:18 +00001502
1503Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001504-----
Tim Peters909c0912001-12-14 23:16:18 +00001505
1506C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001507-----
Tim Peters909c0912001-12-14 23:16:18 +00001508
1509New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001510-------------
Tim Peters909c0912001-12-14 23:16:18 +00001511
1512Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001513-----
Tim Peters909c0912001-12-14 23:16:18 +00001514
1515Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001516-------
Tim Peters909c0912001-12-14 23:16:18 +00001517
Barry Warsaw52acb492001-12-21 20:04:22 +00001518- distutils package: fixed broken Windows installers (bdist_wininst).
1519
1520- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
1521 instances are deleted at process exit time.
1522
1523- socket.py: prevent mysterious warnings when socket instances are
1524 deleted at process exit time.
1525
1526- posixmodule.c: fix a Windows crash with stat() of a filename ending
1527 in backslash.
1528
Tim Peters909c0912001-12-14 23:16:18 +00001529Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001530----
Tim Peters909c0912001-12-14 23:16:18 +00001531
Barry Warsaw52acb492001-12-21 20:04:22 +00001532- The Carbon toolbox modules have been upgraded to Universal Headers
1533 3.4, and experimental CoreGraphics and CarbonEvents modules have
1534 been added. All only for framework-enabled MacOSX.
1535
Tim Peters909c0912001-12-14 23:16:18 +00001536
Tim Peters6272dfd2001-12-13 19:34:00 +00001537What's New in Python 2.2c1?
Tim Petersb3c9af12001-11-17 00:21:57 +00001538===========================
1539
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001540*Release date: 14-Dec-2001*
1541
Tim Petersb3c9af12001-11-17 00:21:57 +00001542Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001543--------------------------------------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001544
Barry Warsaw06557452001-12-14 20:47:12 +00001545- Guido's tutorial introduction to the new type/class features has
1546 been extensively updated. See
1547
1548 http://www.python.org/2.2/descrintro.html
1549
1550 That remains the primary documentation in this area.
1551
Guido van Rossum33bab012001-12-05 22:45:48 +00001552- Fixed a leak: instance variables declared with __slots__ were never
1553 deleted!
1554
Guido van Rossum4b800852001-12-03 00:54:52 +00001555- The "delete attribute" method of descriptor objects is called
1556 __delete__, not __del__. In previous releases, it was mistakenly
1557 called __del__, which created an unfortunate overloading condition
1558 with finalizers. (The "get attribute" and "set attribute" methods
1559 are still called __get__ and __set__, respectively.)
1560
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001561- Some subtle issues with the super built-in were fixed:
1562
1563 (a) When super itself is subclassed, its __get__ method would still
1564 return an instance of the base class (i.e., of super).
1565
1566 (b) super(C, C()).__class__ would return C rather than super. This
1567 is confusing. To fix this, I decided to change the semantics of
1568 super so that it only applies to code attributes, not to data
1569 attributes. After all, overriding data attributes is not
1570 supported anyway.
1571
1572 (c) The __get__ method didn't check whether the argument was an
1573 instance of the type used in creation of the super instance.
1574
Guido van Rossumcd7b7d62001-12-04 21:02:07 +00001575- Previously, hash() of an instance of a subclass of a mutable type
1576 (list or dictionary) would return some value, rather than raising
1577 TypeError. This has been fixed. Also, directly calling
1578 dict.__hash__ and list.__hash__ now raises the same TypeError
1579 (previously, these were the same as object.__hash__).
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001580
Guido van Rossumd331cb52001-12-05 19:46:42 +00001581- New-style objects now support deleting their __dict__. This is for
1582 all intents and purposes equivalent to assigning a brand new empty
1583 dictionary, but saves space if the object is not used further.
1584
Tim Petersb3c9af12001-11-17 00:21:57 +00001585Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001586-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001587
Tim Peters3caca232001-12-06 06:23:26 +00001588- -Qnew now works as documented in PEP 238: when -Qnew is passed on
1589 the command line, all occurrences of "/" use true division instead
1590 of classic division. See the PEP for details. Note that "all"
1591 means all instances in library and 3rd-party modules, as well as in
1592 your own code. As the PEP says, -Qnew is intended for use only in
1593 educational environments with control over the libraries in use.
Tim Petersbf72fe22001-12-11 21:43:14 +00001594 Note that test_coercion.py in the standard Python test suite fails
1595 under -Qnew; this is expected, and won't be repaired until true
1596 division becomes the default (in the meantime, test_coercion is
1597 testing the current rules).
Tim Peters3caca232001-12-06 06:23:26 +00001598
Fred Drake6c01e252001-12-14 17:08:12 +00001599- complex() now only allows the first argument to be a string
1600 argument, and raises TypeError if either the second arg is a string
1601 or if the second arg is specified when the first is a string.
1602
Tim Petersb3c9af12001-11-17 00:21:57 +00001603Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001604-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001605
Martin v. Löwis560da622001-11-24 09:24:51 +00001606- gc.get_referents was renamed to gc.get_referrers.
1607
Tim Petersb3c9af12001-11-17 00:21:57 +00001608Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001609-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001610
Tim Peters25059d32001-12-07 20:35:43 +00001611- Functions in the os.spawn() family now release the global interpreter
1612 lock around calling the platform spawn. They should always have done
1613 this, but did not before 2.2c1. Multithreaded programs calling
1614 an os.spawn function with P_WAIT will no longer block all Python threads
1615 until the spawned program completes. It's possible that some programs
1616 relies on blocking, although more likely by accident than by design.
1617
Martin v. Löwis3a89b2b2001-11-25 14:35:58 +00001618- webbrowser defaults to netscape.exe on OS/2 now.
1619
Martin v. Löwis652e1912001-11-25 14:50:56 +00001620- Tix.ResizeHandle exposes detach_widget, hide, and show.
1621
Martin v. Löwis714d2e22001-12-02 12:26:03 +00001622- The charset alias windows_1252 has been added.
1623
Barry Warsaw06557452001-12-14 20:47:12 +00001624- types.StringTypes is a tuple containing the defined string types;
1625 usually this will be (str, unicode), but if Python was compiled
1626 without Unicode support it will be just (str,).
1627
1628- The pulldom and minidom modules were synchronized to PyXML.
1629
Tim Petersb3c9af12001-11-17 00:21:57 +00001630Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001631-----------
Tim Petersb3c9af12001-11-17 00:21:57 +00001632
Barry Warsaw06557452001-12-14 20:47:12 +00001633- A new script called Tools/scripts/google.py was added, which fires
1634 off a search on Google.
1635
Tim Petersb3c9af12001-11-17 00:21:57 +00001636Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001637-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001638
Barry Warsaw06557452001-12-14 20:47:12 +00001639- Note that release builds of Python should arrange to define the
1640 preprocessor symbol NDEBUG on the command line (or equivalent).
1641 In the 2.2 pre-release series we tried to define this by magic in
1642 Python.h instead, but it proved to cause problems for extension
1643 authors. The Unix, Windows and Mac builds now all define NDEBUG in
1644 release builds via cmdline (or equivalent) instead. Ports to
1645 other platforms should do likewise.
1646
Jack Jansen1999ef42001-12-06 21:47:20 +00001647- It is no longer necessary to use --with-suffix when building on a
1648 case-insensitive file system (such as Mac OS X HFS+). In the build
1649 directory an extension is used, but not in the installed python.
1650
Tim Petersb3c9af12001-11-17 00:21:57 +00001651C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001652-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001653
Tim Petersf582b822001-12-11 18:51:08 +00001654- New function PyDict_MergeFromSeq2() exposes the builtin dict
1655 constructor's logic for updating a dictionary from an iterable object
1656 producing key-value pairs.
1657
Tim Peterscffed4b2001-11-29 03:26:37 +00001658- PyArg_ParseTupleAndKeywords() requires that the number of entries in
Tim Petersf582b822001-12-11 18:51:08 +00001659 the keyword list equal the number of argument specifiers. This
Tim Peterscffed4b2001-11-29 03:26:37 +00001660 wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
1661 dump core in some bad cases. This has been repaired. As a result,
1662 PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
1663 previously went unchallenged.
1664
Tim Petersb3c9af12001-11-17 00:21:57 +00001665New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001666-------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001667
1668Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001669-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001670
1671Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001672-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001673
1674Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001675----
Tim Petersb3c9af12001-11-17 00:21:57 +00001676
Jack Jansenffa260f2001-12-06 21:14:00 +00001677- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
1678 without any trailing digits.
Tim Petersb3c9af12001-11-17 00:21:57 +00001679
Barry Warsaw06557452001-12-14 20:47:12 +00001680- Changed logic for finding python home in Mac OS X framework Pythons.
1681 Now sys.executable points to the executable again, in stead of to
1682 the shared library. The latter is used only for locating the python
1683 home.
1684
1685
Tim Peters84362bc2001-10-19 17:55:30 +00001686What's New in Python 2.2b2?
Tim Peters84362bc2001-10-19 17:55:30 +00001687===========================
1688
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001689*Release date: 16-Nov-2001*
1690
Tim Peters84362bc2001-10-19 17:55:30 +00001691Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001692--------------------------------------------
Tim Peters84362bc2001-10-19 17:55:30 +00001693
Guido van Rossum3d27df02001-11-15 20:27:54 +00001694- Multiple inheritance mixing new-style and classic classes in the
1695 list of base classes is now allowed, so this works now:
Tim Peters76f7fe32001-11-15 20:02:21 +00001696
1697 class Classic: pass
Guido van Rossum3d27df02001-11-15 20:27:54 +00001698 class Mixed(Classic, object): pass
Tim Peters76f7fe32001-11-15 20:02:21 +00001699
1700 The MRO (method resolution order) for each base class is respected
1701 according to its kind, but the MRO for the derived class is computed
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001702 using new-style MRO rules if any base class is a new-style class.
Tim Peters76f7fe32001-11-15 20:02:21 +00001703 This needs to be documented.
1704
Tim Petersa427a2b2001-10-29 22:25:45 +00001705- The new builtin dictionary() constructor, and dictionary type, have
1706 been renamed to dict. This reflects a decade of common usage.
1707
Guido van Rossum3fc08d22001-11-15 20:33:10 +00001708- dict() now accepts an iterable object producing 2-sequences. For
1709 example, dict(d.items()) == d for any dictionary d. The argument,
1710 and the elements of the argument, can be any iterable objects.
1711
Guido van Rossum7ad2d1e2001-10-29 22:11:00 +00001712- New-style classes can now have a __del__ method, which is called
1713 when the instance is deleted (just like for classic classes).
1714
Guido van Rossum12d955c2001-10-26 14:56:06 +00001715- Assignment to object.__dict__ is now possible, for objects that are
1716 instances of new-style classes that have a __dict__ (unless the base
1717 class forbids it).
1718
Guido van Rossumc8e56452001-10-22 00:43:43 +00001719- Methods of built-in types now properly check for keyword arguments
1720 (formerly these were silently ignored). The only built-in methods
1721 that take keyword arguments are __call__, __init__ and __new__.
1722
Guido van Rossum86443212001-10-27 22:28:54 +00001723- The socket function has been converted to a type; see below.
1724
Tim Peters84362bc2001-10-19 17:55:30 +00001725Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001726-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001727
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001728- Assignment to __debug__ raises SyntaxError at compile-time. This
1729 was promised when 2.1c1 was released as "What's New in Python 2.1c1"
Barry Warsaw012852b2001-11-16 16:17:27 +00001730 (see below) says.
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001731
Guido van Rossum12d955c2001-10-26 14:56:06 +00001732- Clarified the error messages for unsupported operands to an operator
1733 (like 1 + '').
1734
Tim Peters84362bc2001-10-19 17:55:30 +00001735Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001736-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001737
Tim Peters5ebfd362001-11-13 23:11:19 +00001738- mmap has a new keyword argument, "access", allowing a uniform way for
1739 both Windows and Unix users to create read-only, write-through and
1740 copy-on-write memory mappings. This was previously possible only on
1741 Unix. A new keyword argument was required to support this in a
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001742 uniform way because the mmap() signatures had diverged across
Tim Peters5ebfd362001-11-13 23:11:19 +00001743 platforms. Thanks to Jay T Miller for repairing this!
1744
Tim Peters169ded02001-11-03 19:57:21 +00001745- By default, the gc.garbage list now contains only those instances in
1746 unreachable cycles that have __del__ methods; in 2.1 it contained all
1747 instances in unreachable cycles. "Instances" here has been generalized
1748 to include instances of both new-style and old-style classes.
1749
Guido van Rossum12d955c2001-10-26 14:56:06 +00001750- The socket module defines a new method for socket objects,
1751 sendall(). This is like send() but may make multiple calls to
Guido van Rossum86443212001-10-27 22:28:54 +00001752 send() until all data has been sent. Also, the socket function has
1753 been converted to a subclassable type, like list and tuple (etc.)
1754 before it; socket and SocketType are now the same thing.
Guido van Rossum12d955c2001-10-26 14:56:06 +00001755
1756- Various bugfixes to the curses module. There is now a test suite
1757 for the curses module (you have to run it manually).
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001758
Guido van Rossum692adf12001-10-30 03:03:03 +00001759- binascii.b2a_base64 no longer places an arbitrary restriction of 57
1760 bytes on its input.
1761
Tim Peters84362bc2001-10-19 17:55:30 +00001762Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001763-------
Tim Peters84362bc2001-10-19 17:55:30 +00001764
Tim Peters5ebfd362001-11-13 23:11:19 +00001765- tkFileDialog exposes a Directory class and askdirectory
Martin v. Löwis25ee87c2001-11-07 22:38:08 +00001766 convenience function.
1767
Tim Peters75335872001-11-03 19:35:43 +00001768- Symbolic group names in regular expressions must be unique. For
1769 example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
1770 single name can't mean both "group 1" and "group 2" simultaneously.
Barry Warsaw012852b2001-11-16 16:17:27 +00001771 Python 2.2 detects this error at regexp compilation time;
1772 previously, the error went undetected, and results were
1773 unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
1774 pattern.subn() methods have been rewritten in C. Also, an
1775 experimental function/method finditer() has been added, which works
1776 like findall() but returns an iterator.
Tim Peters75335872001-11-03 19:35:43 +00001777
Martin v. Löwisb7b32602001-11-02 23:48:20 +00001778- Tix exposes more commands through the classes DirSelectBox,
1779 DirSelectDialog, ListNoteBook, Meter, CheckList, and the
1780 methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
1781 tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
1782
Tim Peters98791af2001-10-23 01:59:54 +00001783- Traceback objects are now scanned by cyclic garbage collection, so
1784 cycles created by casual use of sys.exc_info() no longer cause
1785 permanent memory leaks (provided garbage collection is enabled).
1786
Guido van Rossum49192142001-10-24 20:51:44 +00001787- os.extsep -- a new variable needed by the RISCOS support. It is the
1788 separator used by extensions, and is '.' on all platforms except
1789 RISCOS, where it is '/'. There is no need to use this variable
1790 unless you have a masochistic desire to port your code to RISCOS.
1791
Barry Warsaw012852b2001-11-16 16:17:27 +00001792- mimetypes.py has optional support for non-standard, but commonly
1793 found types. guess_type() and guess_extension() now accept an
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001794 optional 'strict' flag, defaulting to true, which controls whether
Barry Warsaw012852b2001-11-16 16:17:27 +00001795 recognize non-standard types or not. A few non-standard types we
1796 know about have been added. Also, when run as a script, there are
1797 new -l and -e options.
1798
1799- statcache is now deprecated.
1800
1801- email.Utils.formatdate() now produces the preferred RFC 2822 style
1802 dates with numeric timezones (it used to produce obsolete dates
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001803 hard coded to "GMT" timezone). An optional 'localtime' flag is
Barry Warsaw012852b2001-11-16 16:17:27 +00001804 added to produce dates in the local timezone, with daylight savings
1805 time properly taken into account.
1806
1807- In pickle and cPickle, instead of masking errors in load() by
1808 transforming them into SystemError, we let the original exception
1809 propagate out. Also, implement support for __safe_for_unpickling__
1810 in pickle, as it already was supported in cPickle.
1811
Tim Peters84362bc2001-10-19 17:55:30 +00001812Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001813-----------
Tim Peters84362bc2001-10-19 17:55:30 +00001814
1815Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001816-----
Tim Peters84362bc2001-10-19 17:55:30 +00001817
Barry Warsaw012852b2001-11-16 16:17:27 +00001818- The dbm module is built using libdb1 if available. The bsddb module
1819 is built with libdb3 if available.
1820
1821- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
1822
Tim Peters84362bc2001-10-19 17:55:30 +00001823C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001824-----
Tim Peters84362bc2001-10-19 17:55:30 +00001825
Tim Peters1fc240e2001-10-26 05:06:50 +00001826- New function PySequence_Fast_GET_SIZE() returns the size of a non-
1827 NULL result from PySequence_Fast(), more quickly than calling
1828 PySequence_Size().
1829
Barry Warsaw012852b2001-11-16 16:17:27 +00001830- New argument unpacking function PyArg_UnpackTuple() added.
1831
1832- New functions PyObject_CallFunctionObjArgs() and
1833 PyObject_CallMethodObjArgs() have been added to make it more
1834 convenient and efficient to call functions and methods from C.
1835
1836- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
1837 possible that this will propagate errors it didn't before.
1838
1839- New function PyObject_CheckReadBuffer(), which returns true if its
1840 argument supports the single-segment readable buffer interface.
1841
Tim Peters84362bc2001-10-19 17:55:30 +00001842New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001843-------------
Tim Peters84362bc2001-10-19 17:55:30 +00001844
Guido van Rossum86443212001-10-27 22:28:54 +00001845- We've finally confirmed that this release builds on HP-UX 11.00,
1846 *with* threads, and passes the test suite.
1847
Tim Peters7a33d8b2001-11-05 02:51:07 +00001848- Thanks to a series of patches from Michael Muller, Python may build
1849 again under OS/2 Visual Age C++.
1850
Guido van Rossum49192142001-10-24 20:51:44 +00001851- Updated RISCOS port by Dietmar Schwertberger.
1852
Tim Peters84362bc2001-10-19 17:55:30 +00001853Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001854-----
Tim Peters84362bc2001-10-19 17:55:30 +00001855
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001856- Added a test script for the curses module. It isn't run automatically;
1857 regrtest.py must be run with '-u curses' to enable it.
1858
Tim Peters84362bc2001-10-19 17:55:30 +00001859Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001860-------
Tim Peters84362bc2001-10-19 17:55:30 +00001861
Barry Warsaw012852b2001-11-16 16:17:27 +00001862Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001863----
Barry Warsaw012852b2001-11-16 16:17:27 +00001864
1865- PythonScript has been moved to unsupported and is slated to be
1866 removed completely in the next release.
1867
1868- It should now be possible to build applets that work on both OS9 and
1869 OSX.
1870
1871- The core is now linked with CoreServices not Carbon; as a side
1872 result, default 8bit encoding on OSX is now ASCII.
1873
1874- Python should now build on OSX 10.1.1
1875
Tim Peters84362bc2001-10-19 17:55:30 +00001876
Tim Petersabf925f2001-09-28 21:53:42 +00001877What's New in Python 2.2b1?
Tim Petersabf925f2001-09-28 21:53:42 +00001878===========================
1879
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001880*Release date: 19-Oct-2001*
1881
Tim Petersabf925f2001-09-28 21:53:42 +00001882Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001883--------------------------------------------
Tim Petersabf925f2001-09-28 21:53:42 +00001884
Guido van Rossum687ae002001-10-15 22:03:32 +00001885- New-style classes are now always dynamic (except for built-in and
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001886 extension types). There is no longer a performance penalty, and I
Guido van Rossum687ae002001-10-15 22:03:32 +00001887 no longer see another reason to keep this baggage around. One relic
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001888 remains: the __dict__ of a new-style class is a read-only proxy; you
1889 must set the class's attribute to modify it. As a consequence, the
Guido van Rossum687ae002001-10-15 22:03:32 +00001890 __defined__ attribute of new-style types no longer exists, for lack
1891 of need: there is once again only one __dict__ (although in the
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001892 future a __cache__ may be resurrected with a similar function, if I
1893 can prove that it actually speeds things up).
Guido van Rossum50fda3b2001-10-04 19:46:06 +00001894
Tim Peters1c9ca872001-10-04 06:43:12 +00001895- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
1896 always returned None, even when there was a class docstring).
1897
1898- doctest now finds and runs docstrings attached to new-style classes,
1899 class methods, static methods, and properties.
1900
Guido van Rossum9074ef62001-10-16 21:34:49 +00001901Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001902-----------------
Tim Petersabf925f2001-09-28 21:53:42 +00001903
Guido van Rossuma8bcf802001-10-15 15:53:58 +00001904- A very subtle syntactical pitfall in list comprehensions was fixed.
1905 For example: [a+b for a in 'abc', for b in 'def']. The comma in
1906 this example is a mistake. Previously, this would silently let 'a'
1907 iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
1908 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
1909 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
1910 Note that [a for a in <singleton>] is a convoluted way to say
1911 [<singleton>] anyway, so it's not like any expressiveness is lost.
1912
Guido van Rossum9074ef62001-10-16 21:34:49 +00001913- getattr(obj, name, default) now only catches AttributeError, as
1914 documented, rather than returning the default value for all
1915 exceptions (which could mask bugs in a __getattr__ hook, for
1916 example).
1917
Fred Drakecb7a6b52001-10-22 18:41:51 +00001918- Weak reference objects are now part of the core and offer a C API.
Fred Drake934d2a42001-10-18 18:18:06 +00001919 A bug which could allow a core dump when binary operations involved
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001920 proxy reference has been fixed. weakref.ReferenceError is now a
Barry Warsawf6fb1712001-10-19 05:35:40 +00001921 built-in exception.
Fred Drake934d2a42001-10-18 18:18:06 +00001922
Guido van Rossum1c486092001-10-19 02:05:35 +00001923- unicode(obj) now behaves more like str(obj), accepting arbitrary
1924 objects, and calling a __unicode__ method if it exists.
1925 unicode(obj, encoding) and unicode(obj, encoding, errors) still
Marc-André Lemburgb5507ec2001-10-19 12:02:29 +00001926 require an 8-bit string or character buffer argument.
Guido van Rossum1c486092001-10-19 02:05:35 +00001927
Barry Warsawf6fb1712001-10-19 05:35:40 +00001928- isinstance() now allows any object as the first argument and a
1929 class, a type or something with a __bases__ tuple attribute for the
1930 second argument. The second argument may also be a tuple of a
1931 class, type, or something with __bases__, in which case isinstance()
1932 will return true if the first argument is an instance of any of the
1933 things contained in the second argument tuple. E.g.
1934
1935 isinstance(x, (A, B))
1936
1937 returns true if x is an instance of A or B.
1938
Guido van Rossum9074ef62001-10-16 21:34:49 +00001939Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001940-----------------
Guido van Rossum9074ef62001-10-16 21:34:49 +00001941
1942- thread.start_new_thread() now returns the thread ID (previously None).
1943
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001944- binascii has now two quopri support functions, a2b_qp and b2a_qp.
1945
Guido van Rossumc524d952001-10-19 01:31:59 +00001946- readline now supports setting the startup_hook and the
1947 pre_event_hook, and adds the add_history() function.
Martin v. Löwis0daad592001-09-30 21:09:59 +00001948
Guido van Rossumc524d952001-10-19 01:31:59 +00001949- os and posix supports chroot(), setgroups() and unsetenv() where
1950 available. The stat(), fstat(), statvfs() and fstatvfs() functions
1951 now return "pseudo-sequences" -- the various fields can now be
1952 accessed as attributes (e.g. os.stat("/").st_mtime) but for
1953 backwards compatibility they also behave as a fixed-length sequence.
1954 Some platform-specific fields (e.g. st_rdev) are only accessible as
Guido van Rossum98bf58f2001-10-18 20:34:25 +00001955 attributes.
1956
1957- time: localtime(), gmtime() and strptime() now return a
1958 pseudo-sequence similar to the os.stat() return value, with
1959 attributes like tm_year etc.
Martin v. Löwis16628c92001-10-04 22:46:41 +00001960
Guido van Rossum9074ef62001-10-16 21:34:49 +00001961- Decompression objects in the zlib module now accept an optional
1962 second parameter to decompress() that specifies the maximum amount
1963 of memory to use for the uncompressed data.
Tim Petersabf925f2001-09-28 21:53:42 +00001964
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001965- optional SSL support in the socket module now exports OpenSSL
1966 functions RAND_add(), RAND_egd(), and RAND_status(). These calls
1967 are useful on platforms like Solaris where OpenSSL does not
Barry Warsawf6fb1712001-10-19 05:35:40 +00001968 automatically seed its PRNG. Also, the keyfile and certfile
1969 arguments to socket.ssl() are now optional.
1970
1971- posixmodule (and by extension, the os module on POSIX platforms) now
1972 exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001973
Guido van Rossum9074ef62001-10-16 21:34:49 +00001974Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001975-------
Guido van Rossum3c288632001-10-16 21:13:49 +00001976
Tim Peters7402f792001-10-02 03:53:41 +00001977- doctest now excludes functions and classes not defined by the module
1978 being tested, thanks to Tim Hochberg.
1979
Fred Drakecb7a6b52001-10-22 18:41:51 +00001980- HotShot, a new profiler implemented using a C-based callback, has
1981 been added. This substantially reduces the overhead of profiling,
1982 but it is still quite preliminary. Support modules and
1983 documentation will be added in upcoming releases (before 2.2 final).
1984
Guido van Rossumc4b09b42001-10-04 10:19:00 +00001985- profile now produces correct output in situations where an exception
1986 raised in Python is cleared by C code (e.g. hasattr()). This used
1987 to cause wrong output, including spurious claims of recursive
1988 functions and attribution of time spent to the wrong function.
1989
Tim Peters0a1fc4e2001-10-07 03:12:08 +00001990 The code and documentation for the derived OldProfile and HotProfile
1991 profiling classes was removed. The code hasn't worked for years (if
1992 you tried to use them, they raised exceptions). OldProfile
1993 intended to reproduce the behavior of the profiler Python used more
1994 than 7 years ago, and isn't interesting anymore. HotProfile intended
1995 to provide a faster profiler (but producing less information), and
1996 that's a worthy goal we intend to meet via a different approach (but
1997 without losing information).
1998
Tim Peterscce092d2001-10-09 05:31:56 +00001999- Profile.calibrate() has a new implementation that should deliver
Tim Peters659a6032001-10-09 20:51:19 +00002000 a much better system-specific calibration constant. The constant can
2001 now be specified in an instance constructor, or as a Profile class or
2002 instance variable, instead of by editing profile.py's source code.
2003 Calibration must still be done manually (see the docs for the profile
2004 module).
2005
2006 Note that Profile.calibrate() must be overriden by subclasses.
2007 Improving the accuracy required exploiting detailed knowledge of
2008 profiler internals; the earlier method abstracted away the details
2009 and measured a simplified model instead, but consequently computed
2010 a constant too small by a factor of 2 on some modern machines.
Tim Peterscce092d2001-10-09 05:31:56 +00002011
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00002012- quopri's encode and decode methods take an optional header parameter,
Jeremy Hylton6f543b62001-10-16 20:42:52 +00002013 which indicates whether output is intended for the header 'Q'
2014 encoding.
2015
Guido van Rossuma5343cc2001-10-18 18:02:07 +00002016- The SocketServer.ThreadingMixIn class now closes the request after
2017 finish_request() returns. (Not when it errors out though.)
2018
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002019- The nntplib module's NNTP.body() method has grown a 'file' argument
Barry Warsawf6fb1712001-10-19 05:35:40 +00002020 to allow saving the message body to a file.
2021
2022- The email package has added a class email.Parser.HeaderParser which
2023 only parses headers and does not recurse into the message's body.
2024 Also, the module/class MIMEAudio has been added for representing
2025 audio data (contributed by Anthony Baxter).
2026
2027- ftplib should be able to handle files > 2GB.
2028
2029- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
2030 ON, and OFF.
2031
Fred Drakecb7a6b52001-10-22 18:41:51 +00002032- xml.dom.minidom NodeList objects now support the length attribute
2033 and item() method as required by the DOM specifications.
2034
Guido van Rossumed554f62001-10-02 23:15:37 +00002035Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002036-----------
Guido van Rossumed554f62001-10-02 23:15:37 +00002037
2038- Demo/dns was removed. It no longer serves any purpose; a package
2039 derived from it is now maintained by Anthony Baxter, see
2040 http://PyDNS.SourceForge.net.
Tim Petersabf925f2001-09-28 21:53:42 +00002041
Barry Warsawf6fb1712001-10-19 05:35:40 +00002042- The freeze tool has been made more robust, and two new options have
2043 been added: -X and -E.
2044
Tim Petersabf925f2001-09-28 21:53:42 +00002045Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002046-----
Tim Petersabf925f2001-09-28 21:53:42 +00002047
Barry Warsawf6fb1712001-10-19 05:35:40 +00002048- configure will use CXX in LINKCC if CXX is used to build main() and
2049 the system requires to link a C++ main using the C++ compiler.
2050
Tim Petersabf925f2001-09-28 21:53:42 +00002051C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002052-----
Tim Petersabf925f2001-09-28 21:53:42 +00002053
Guido van Rossum6c4bce32001-10-18 19:20:25 +00002054- The documentation for the tp_compare slot is updated to require that
2055 the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
2056 not correct. This is not yet enforced but will be enforced in
2057 Python 2.3; even later, we may use -2 to indicate errors and +2 for
2058 "NotImplemented". Right now, -1 should be used for an error return.
2059
Tim Petersd38b1c72001-09-30 05:09:37 +00002060- PyLong_AsLongLong() now accepts int (as well as long) arguments.
2061 Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
2062 as long) arguments.
2063
Guido van Rossum3c288632001-10-16 21:13:49 +00002064- PyThread_start_new_thread() now returns a long int giving the thread
2065 ID, if one can be calculated; it returns -1 for error, 0 if no
2066 thread ID is calculated (this is an incompatible change, but only
2067 the thread module used this API). This code has only really been
2068 tested on Linux and Windows; other platforms please beware (and
2069 report any bugs or strange behavior).
2070
Guido van Rossum1c486092001-10-19 02:05:35 +00002071- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
2072 input.
2073
Tim Petersabf925f2001-09-28 21:53:42 +00002074New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002075-------------
Tim Petersabf925f2001-09-28 21:53:42 +00002076
2077Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002078-----
Tim Petersabf925f2001-09-28 21:53:42 +00002079
2080Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002081-------
Tim Petersabf925f2001-09-28 21:53:42 +00002082
Tim Peters04cf1d32001-10-09 22:39:40 +00002083- Installer: If you install IDLE, and don't disable file-extension
2084 registration, a new "Edit with IDLE" context (right-click) menu entry
2085 is created for .py and .pyw files.
2086
Tim Peters1ce3cf72001-10-01 17:58:40 +00002087- The signal module now supports SIGBREAK on Windows, thanks to Steven
2088 Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
2089 action remains to call Win32 ExitProcess(). This can be changed via
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002090 signal.signal(). For example::
Tim Peters1ce3cf72001-10-01 17:58:40 +00002091
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002092 # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
2093 # (SIGINT) behavior.
2094 import signal
2095 signal.signal(signal.SIGBREAK, signal.default_int_handler)
Tim Peters1ce3cf72001-10-01 17:58:40 +00002096
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002097 try:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002098 while 1:
2099 pass
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002100 except KeyboardInterrupt:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002101 # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
2102 # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
2103 # program without the possibility for any Python-level cleanup).
2104 print "Clean exit"
Tim Peters1ce3cf72001-10-01 17:58:40 +00002105
Tim Petersabf925f2001-09-28 21:53:42 +00002106
Tim Petersb07352e2001-09-08 01:25:47 +00002107What's New in Python 2.2a4?
2108===========================
2109
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002110*Release date: 28-Sep-2001*
2111
Guido van Rossum808eea72001-09-25 04:15:41 +00002112Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002113--------------------------------------------
Guido van Rossum808eea72001-09-25 04:15:41 +00002114
2115- pydoc and inspect are now aware of new-style classes;
2116 e.g. help(list) at the interactive prompt now shows proper
2117 documentation for all operations on list objects.
2118
2119- Applications using Jim Fulton's ExtensionClass module can now safely
2120 be used with Python 2.2. In particular, Zope 2.4.1 now works with
2121 Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
2122 examples also work again. It is hoped that Gtk and Boost also work
2123 with 2.2a4 and beyond. (If you can confirm this, please write
2124 webmaster@python.org; if there are still problems, please open a bug
2125 report on SourceForge.)
Tim Petersb07352e2001-09-08 01:25:47 +00002126
Tim Peters66c1a522001-09-24 21:17:50 +00002127- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00002128 These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
Tim Peters66c1a522001-09-24 21:17:50 +00002129 in the constructed property object. fget, fset and fdel weren't
2130 discoverable from Python in 2.2a3. __doc__ is new, and allows to
2131 associate a docstring with a property.
2132
Guido van Rossum808eea72001-09-25 04:15:41 +00002133- Comparison overloading is now more completely implemented. For
2134 example, a str subclass instance can properly be compared to a str
2135 instance, and it can properly overload comparison. Ditto for most
2136 other built-in object types.
2137
2138- The repr() of new-style classes has changed; instead of <type
2139 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
2140 *except* for built-in types, which are still rendered as <type
2141 'Foo'> (to avoid upsetting existing code that might parse or
2142 otherwise rely on repr() of certain type objects).
2143
2144- The repr() of new-style objects is now always <Foo object at XXX>;
2145 previously, it was sometimes <Foo instance at XXX>.
2146
2147- For new-style classes, what was previously called __getattr__ is now
2148 called __getattribute__. This method, if defined, is called for
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00002149 *every* attribute access. A new __getattr__ hook more similar to the
Guido van Rossum808eea72001-09-25 04:15:41 +00002150 one in classic classes is defined which is called only if regular
2151 attribute access raises AttributeError; to catch *all* attribute
2152 access, you can use __getattribute__ (for new-style classes). If
2153 both are defined, __getattribute__ is called first, and if it raises
2154 AttributeError, __getattr__ is called.
2155
2156- The __class__ attribute of new-style objects can be assigned to.
2157 The new class must have the same C-level object layout as the old
2158 class.
2159
2160- The builtin file type can be subclassed now. In the usual pattern,
2161 "file" is the name of the builtin type, and file() is a new builtin
2162 constructor, with the same signature as the builtin open() function.
2163 file() is now the preferred way to open a file.
2164
2165- Previously, __new__ would only see sequential arguments passed to
2166 the type in a constructor call; __init__ would see both sequential
2167 and keyword arguments. This made no sense whatsoever any more, so
2168 now both __new__ and __init__ see all arguments.
2169
2170- Previously, hash() applied to an instance of a subclass of str or
2171 unicode always returned 0. This has been repaired.
2172
2173- Previously, an operation on an instance of a subclass of an
2174 immutable type (int, long, float, complex, tuple, str, unicode),
2175 where the subtype didn't override the operation (and so the
2176 operation was handled by the builtin type), could return that
2177 instance instead a value of the base type. For example, if s was of
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00002178 a str subclass type, s[:] returned s as-is. Now it returns a str
Guido van Rossum808eea72001-09-25 04:15:41 +00002179 with the same value as s.
2180
Barry Warsaw86fbaf82001-09-28 15:26:12 +00002181- Provisional support for pickling new-style objects has been added.
2182
Guido van Rossum808eea72001-09-25 04:15:41 +00002183Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002184----
Guido van Rossum808eea72001-09-25 04:15:41 +00002185
Tim Peters2c9aa5e2001-09-23 04:06:05 +00002186- file.writelines() now accepts any iterable object producing strings.
2187
Marc-André Lemburgaefd7662001-09-20 12:59:37 +00002188- PyUnicode_FromEncodedObject() now works very much like
2189 PyObject_Str(obj) in that it tries to use __str__/tp_str
2190 on the object if the object is not a string or buffer. This
2191 makes unicode() behave like str() when applied to non-string/buffer
2192 objects.
2193
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00002194- PyFile_WriteObject now passes Unicode objects to the file's write
2195 method. As a result, all file-like objects which may be the target
Martin v. Löwis2777c022001-09-19 13:47:32 +00002196 of a print statement must support Unicode objects, i.e. they must
2197 at least convert them into ASCII strings.
2198
Guido van Rossum624c8af2001-09-18 15:21:04 +00002199- Thread scheduling on Solaris should be improved; it is no longer
2200 necessary to insert a small sleep at the start of a thread in order
2201 to let other runnable threads be scheduled.
2202
Tim Petersb07352e2001-09-08 01:25:47 +00002203Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002204-------
Tim Petersb07352e2001-09-08 01:25:47 +00002205
Marc-André Lemburgbf990172001-09-27 14:17:33 +00002206- StringIO.StringIO instances and cStringIO.StringIO instances support
2207 read character buffer compatible objects for their .write() methods.
2208 These objects are converted to strings and then handled as such
2209 by the instances.
2210
Barry Warsaw2f600732001-09-24 04:28:10 +00002211- The "email" package has been added. This is basically a port of the
2212 mimelib package <http://sf.net/projects/mimelib> with API changes
2213 and some implementations updated to use iterators and generators.
2214
Tim Peters8a9c2842001-09-22 21:30:22 +00002215- difflib.ndiff() and difflib.Differ.compare() are generators now. This
2216 restores the ability of Tools/scripts/ndiff.py to start producing output
2217 before the entire comparison is complete.
2218
Barry Warsaw58b072d2001-09-22 04:44:21 +00002219- StringIO.StringIO instances and cStringIO.StringIO instances support
2220 iteration just like file objects (i.e. their .readline() method is
2221 called for each iteration until it returns an empty string).
2222
Marc-André Lemburg494f2ae2001-09-19 11:33:31 +00002223- The codecs module has grown four new helper APIs to access
2224 builtin codecs: getencoder(), getdecoder(), getreader(),
2225 getwriter().
2226
Guido van Rossum624c8af2001-09-18 15:21:04 +00002227- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
2228 simplifies writing XML RPC servers.
2229
Barry Warsaw647d5e82001-09-28 17:01:02 +00002230- os.path.realpath(): a new function that returns the absolute pathname
Guido van Rossum624c8af2001-09-18 15:21:04 +00002231 after interpretation of symbolic links. On non-Unix systems, this
2232 is an alias for os.path.abspath().
2233
Tim Peters16a77ad2001-09-08 04:00:12 +00002234- operator.indexOf() (PySequence_Index() in the C API) now works with any
2235 iterable object.
2236
Guido van Rossum624c8af2001-09-18 15:21:04 +00002237- smtplib now supports various authentication and security features of
2238 the SMTP protocol through the new login() and starttls() methods.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00002239
Guido van Rossum624c8af2001-09-18 15:21:04 +00002240- hmac: a new module implementing keyed hashing for message
2241 authentication.
2242
2243- mimetypes now recognizes more extensions and file types. At the
2244 same time, some mappings not sanctioned by IANA were removed.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00002245
Guido van Rossum624c8af2001-09-18 15:21:04 +00002246- The "compiler" package has been brought up to date to the state of
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00002247 Python 2.2 bytecode generation. It has also been promoted from a
2248 Tool to a standard library package. (Tools/compiler still exists as
2249 a sample driver.)
2250
Tim Petersb07352e2001-09-08 01:25:47 +00002251Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002252-----
Tim Petersb07352e2001-09-08 01:25:47 +00002253
Guido van Rossum624c8af2001-09-18 15:21:04 +00002254- Large file support (LFS) is now automatic when the platform supports
2255 it; no more manual configuration tweaks are needed. On Linux, at
2256 least, it's possible to have a system whose C library supports large
2257 files but whose kernel doesn't; in this case, large file support is
2258 still enabled but doesn't do you any good unless you upgrade your
2259 kernel or share your Python executable with another system whose
2260 kernel has large file support.
2261
2262- The configure script now supplies plausible defaults in a
2263 cross-compilation environment. This doesn't mean that the supplied
2264 values are always correct, or that cross-compilation now works
2265 flawlessly -- but it's a first step (and it shuts up most of
2266 autoconf's warnings about AC_TRY_RUN).
2267
2268- The Unix build is now a bit less chatty, courtesy of the parser
2269 generator. The build is completely silent (except for errors) when
2270 using "make -s", thanks to a -q option to setup.py.
2271
Tim Petersb07352e2001-09-08 01:25:47 +00002272C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002273-----
Tim Petersb07352e2001-09-08 01:25:47 +00002274
Guido van Rossum624c8af2001-09-18 15:21:04 +00002275- The "structmember" API now supports some new flag bits to deny read
2276 and/or write access to attributes in restricted execution mode.
2277
Tim Petersb07352e2001-09-08 01:25:47 +00002278New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002279-------------
Tim Petersb07352e2001-09-08 01:25:47 +00002280
Guido van Rossum624c8af2001-09-18 15:21:04 +00002281- Compaq's iPAQ handheld, running the "familiar" Linux distribution
2282 (http://familiar.handhelds.org).
2283
Tim Petersb07352e2001-09-08 01:25:47 +00002284Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002285-----
Tim Petersb07352e2001-09-08 01:25:47 +00002286
Tim Peters8a9c2842001-09-22 21:30:22 +00002287- The "classic" standard tests, which work by comparing stdout to
2288 an expected-output file under Lib/test/output/, no longer stop at
2289 the first mismatch. Instead the test is run to completion, and a
2290 variant of ndiff-style comparison is used to report all differences.
2291 This is much easier to understand than the previous style of reporting.
2292
2293- The unittest-based standard tests now use regrtest's test_main()
2294 convention, instead of running as a side-effect of merely being
2295 imported. This allows these tests to be run in more natural and
2296 flexible ways as unittests, outside the regrtest framework.
2297
2298- regrtest.py is much better integrated with unittest and doctest now,
2299 especially in regard to reporting errors.
2300
Tim Petersb07352e2001-09-08 01:25:47 +00002301Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002302-------
Tim Petersb07352e2001-09-08 01:25:47 +00002303
Guido van Rossum624c8af2001-09-18 15:21:04 +00002304- Large file support now also works for files > 4GB, on filesystems
Tim Peters8a9c2842001-09-22 21:30:22 +00002305 that support it (NTFS under Windows 2000). See "What's New in
2306 Python 2.2a3" for more detail.
Guido van Rossum624c8af2001-09-18 15:21:04 +00002307
Tim Petersb07352e2001-09-08 01:25:47 +00002308
Tim Petersedc99312001-08-22 21:36:50 +00002309What's New in Python 2.2a3?
2310===========================
2311
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002312*Release Date: 07-Sep-2001*
2313
Tim Petersedc99312001-08-22 21:36:50 +00002314Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002315----
Tim Petersedc99312001-08-22 21:36:50 +00002316
Tim Peters9fffa3e2001-09-04 05:14:19 +00002317- Conversion of long to float now raises OverflowError if the long is too
2318 big to represent as a C double.
2319
Tim Peters32f453e2001-09-03 08:35:41 +00002320- The 3-argument builtin pow() no longer allows a third non-None argument
2321 if either of the first two arguments is a float, or if both are of
2322 integer types and the second argument is negative (in which latter case
2323 the arguments are converted to float, so this is really the same
2324 restriction).
2325
Tim Peters5d2b77c2001-09-03 05:47:38 +00002326- The builtin dir() now returns more information, and sometimes much
2327 more, generally naming all attributes of an object, and all attributes
2328 reachable from the object via its class, and from its class's base
2329 classes, and so on from them too. Example: in 2.2a2, dir([]) returned
2330 an empty list. In 2.2a3,
2331
2332 >>> dir([])
2333 ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
2334 '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
2335 '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
2336 '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
2337 '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
2338 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
2339 'reverse', 'sort']
2340
2341 dir(module) continues to return only the module's attributes, though.
2342
Tim Petersbdee63f2001-09-02 03:40:59 +00002343- Overflowing operations on plain ints now return a long int rather
Guido van Rossumae457142001-08-31 18:31:35 +00002344 than raising OverflowError. This is a partial implementation of PEP
2345 237. You can use -Wdefault::OverflowWarning to enable a warning for
2346 this situation, and -Werror::OverflowWarning to revert to the old
2347 OverflowError exception.
2348
Guido van Rossum61c345f2001-09-04 03:26:15 +00002349- A new command line option, -Q<arg>, is added to control run-time
Guido van Rossumae457142001-08-31 18:31:35 +00002350 warnings for the use of classic division. (See PEP 238.) Possible
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002351 values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
2352 -Qold, meaning the / operator has its classic meaning and no
2353 warnings are issued. Using -Qwarn issues a run-time warning about
2354 all uses of classic division for int and long arguments; -Qwarnall
2355 also warns about classic division for float and complex arguments
Tim Peters3caca232001-12-06 06:23:26 +00002356 (for use with fixdiv.py).
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002357 [Note: the remainder of this item (preserved below) became
2358 obsolete in 2.2c1 -- -Qnew has global effect in 2.2] ::
2359
2360 Using -Qnew is questionable; it turns on new division by default, but
2361 only in the __main__ module. You can usefully combine -Qwarn or
2362 -Qwarnall and -Qnew: this gives the __main__ module new division, and
2363 warns about classic division everywhere else.
Guido van Rossumae457142001-08-31 18:31:35 +00002364
Tim Petersbdee63f2001-09-02 03:40:59 +00002365- Many built-in types can now be subclassed. This applies to int,
Guido van Rossumae457142001-08-31 18:31:35 +00002366 long, float, str, unicode, and tuple. (The types complex, list and
2367 dictionary can also be subclassed; this was introduced earlier.)
2368 Note that restrictions apply when subclassing immutable built-in
2369 types: you can only affect the value of the instance by overloading
2370 __new__. You can add mutable attributes, and the subclass instances
2371 will have a __dict__ attribute, but you cannot change the "value"
2372 (as implemented by the base class) of an immutable subclass instance
2373 once it is created.
2374
Guido van Rossumaaf80c82001-09-02 13:44:35 +00002375- The dictionary constructor now takes an optional argument, a
2376 mapping-like object, and initializes the dictionary from its
2377 (key, value) pairs.
2378
Tim Petersbdee63f2001-09-02 03:40:59 +00002379- A new built-in type, super, has been added. This facilitates making
Guido van Rossumae457142001-08-31 18:31:35 +00002380 "cooperative super calls" in a multiple inheritance setting. For an
2381 explanation, see http://www.python.org/2.2/descrintro.html#cooperation
2382
Guido van Rossum8d7234d2001-09-06 22:02:58 +00002383- A new built-in type, property, has been added. This enables the
2384 creation of "properties". These are attributes implemented by
2385 getter and setter functions (or only one of these for read-only or
2386 write-only attributes), without the need to override __getattr__.
2387 See http://www.python.org/2.2/descrintro.html#property
Guido van Rossumae457142001-08-31 18:31:35 +00002388
Tim Petersbdee63f2001-09-02 03:40:59 +00002389- The syntax of floating-point and imaginary literals has been
Tim Petersd507dab2001-08-30 20:51:59 +00002390 liberalized, to allow leading zeroes. Examples of literals now
2391 legal that were SyntaxErrors before:
2392
2393 00.0 0e3 0100j 07.5 00000000000000000008.
2394
Tim Petersbdee63f2001-09-02 03:40:59 +00002395- An old tokenizer bug allowed floating point literals with an incomplete
Tim Petersc6d95812001-08-28 20:56:27 +00002396 exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
2397
Tim Petersedc99312001-08-22 21:36:50 +00002398Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002399-------
Tim Petersedc99312001-08-22 21:36:50 +00002400
Martin v. Löwiscb227c92001-09-06 08:54:16 +00002401- telnetlib includes symbolic names for the options, and support for
Martin v. Löwis1da9c572002-11-04 09:56:00 +00002402 setting an option negotiation callback. It also supports processing
2403 of suboptions.
Martin v. Löwiscb227c92001-09-06 08:54:16 +00002404
Tim Petersa40c7932001-09-05 22:36:56 +00002405- The new C standard no longer requires that math libraries set errno to
2406 ERANGE on overflow. For platform libraries that exploit this new
2407 freedom, Python's overflow-checking was wholly broken. A new overflow-
2408 checking scheme attempts to repair that, but may not be reliable on all
2409 platforms (C doesn't seem to provide anything both useful and portable
2410 in this area anymore).
2411
Martin v. Löwis44f86962001-09-05 13:44:54 +00002412- Asynchronous timeout actions are available through the new class
2413 threading.Timer.
2414
Tim Peters78526162001-09-05 00:53:45 +00002415- math.log and math.log10 now return sensible results for even huge
2416 long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
2417
Tim Petersbdee63f2001-09-02 03:40:59 +00002418- A new function, imp.lock_held(), returns 1 when the import lock is
Tim Peters69232342001-08-30 05:16:13 +00002419 currently held. See the docs for the imp module.
2420
Tim Petersbdee63f2001-09-02 03:40:59 +00002421- pickle, cPickle and marshal on 32-bit platforms can now correctly read
Tim Peters82112372001-08-29 02:28:42 +00002422 dumps containing ints written on platforms where Python ints are 8 bytes.
2423 When read on a box where Python ints are 4 bytes, such values are
2424 converted to Python longs.
2425
Tim Petersbdee63f2001-09-02 03:40:59 +00002426- In restricted execution mode (using the rexec module), unmarshalling
Guido van Rossumae457142001-08-31 18:31:35 +00002427 code objects is no longer allowed. This plugs a security hole.
2428
Steve Purcell6091cd62001-09-06 16:05:17 +00002429- unittest.TestResult instances no longer store references to tracebacks
2430 generated by test failures. This prevents unexpected dangling references
2431 to objects that should be garbage collected between tests.
2432
Tim Petersedc99312001-08-22 21:36:50 +00002433Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002434-----
Tim Petersedc99312001-08-22 21:36:50 +00002435
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002436- Tools/scripts/fixdiv.py has been added which can be used to fix
2437 division operators as per PEP 238.
2438
Tim Petersedc99312001-08-22 21:36:50 +00002439Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002440-----
Tim Petersedc99312001-08-22 21:36:50 +00002441
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002442- If you are an adventurous person using Mac OS X you may want to look at
2443 Mac/OSX. There is a Makefile there that will build Python as a real Mac
2444 application, which can be used for experimenting with Carbon or Cocoa.
2445 Discussion of this on pythonmac-sig, please.
2446
Tim Peters7eea37e2001-09-04 22:08:56 +00002447C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002448-----
Tim Peters7eea37e2001-09-04 22:08:56 +00002449
2450- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
Tim Peters69232342001-08-30 05:16:13 +00002451
Tim Peters9fffa3e2001-09-04 05:14:19 +00002452- Note that PyLong_AsDouble can fail! This has always been true, but no
2453 callers checked for it. It's more likely to fail now, because overflow
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002454 errors are properly detected now. The proper way to check::
Tim Peters9fffa3e2001-09-04 05:14:19 +00002455
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002456 double x = PyLong_AsDouble(some_long_object);
2457 if (x == -1.0 && PyErr_Occurred()) {
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002458 /* The conversion failed. */
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002459 }
Tim Peters9fffa3e2001-09-04 05:14:19 +00002460
Tim Petersbdee63f2001-09-02 03:40:59 +00002461- The GC API has been changed. Extensions that use the old API will still
Neil Schemenauer4042c692001-08-30 15:38:01 +00002462 compile but will not participate in GC. To upgrade an extension
2463 module:
2464
2465 - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
Tim Petersd507dab2001-08-30 20:51:59 +00002466
Neil Schemenauer4042c692001-08-30 15:38:01 +00002467 - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
2468 PyObject_GC_Del to deallocate them
Tim Petersd507dab2001-08-30 20:51:59 +00002469
Neil Schemenauer4042c692001-08-30 15:38:01 +00002470 - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
2471 to PyObject_GC_UnTrack
Tim Petersd507dab2001-08-30 20:51:59 +00002472
Neil Schemenauer4042c692001-08-30 15:38:01 +00002473 - remove PyGC_HEAD_SIZE from object size calculations
2474
2475 - remove calls to PyObject_AS_GC and PyObject_FROM_GC
2476
Tim Petersbdee63f2001-09-02 03:40:59 +00002477- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
Guido van Rossumae457142001-08-31 18:31:35 +00002478 These can be used safely to construct string objects from a
2479 sprintf-style format string (similar to the format string supported
2480 by PyErr_Format()).
Tim Peters69232342001-08-30 05:16:13 +00002481
Tim Petersedc99312001-08-22 21:36:50 +00002482New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002483-------------
Tim Petersedc99312001-08-22 21:36:50 +00002484
Tim Petersb7da0902001-09-02 23:01:43 +00002485- Stephen Hansen contributed patches sufficient to get a clean compile
2486 under Borland C (Windows), but he reports problems running it and ran
2487 out of time to complete the port. Volunteers? Expect a MemoryError
2488 when importing the types module; this is probably shallow, and
2489 causing later failures too.
Tim Petersbdee63f2001-09-02 03:40:59 +00002490
Tim Petersedc99312001-08-22 21:36:50 +00002491Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002492-----
Tim Petersedc99312001-08-22 21:36:50 +00002493
2494Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002495-------
Tim Petersedc99312001-08-22 21:36:50 +00002496
Tim Peters6e13a562001-09-06 00:32:15 +00002497- Large file support is now enabled on Win32 platforms as well as on
2498 Win64. This means that, for example, you can use f.tell() and f.seek()
2499 to manipulate files larger than 2 gigabytes (provided you have enough
2500 disk space, and are using a Windows filesystem that supports large
Tim Peters9a9471c2001-09-11 23:18:51 +00002501 partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
2502 filesize limit, and large file support makes no difference there.
2503 FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
2504 NTFS has no practical limit on file size, and files of any size can be
2505 used from Python now.
Tim Peters6e13a562001-09-06 00:32:15 +00002506
Tim Petersbdee63f2001-09-02 03:40:59 +00002507- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
Tim Peters402d5982001-08-27 06:37:48 +00002508 points to command.com (patch from Brian Quinlan).
2509
Tim Petersedc99312001-08-22 21:36:50 +00002510
Tim Peters20f51a72001-07-21 02:31:40 +00002511What's New in Python 2.2a2?
2512===========================
2513
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002514*Release Date: 22-Aug-2001*
2515
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002516Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002517-----
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002518
Barry Warsaw18b2ecf2001-08-22 20:26:56 +00002519- Tim Peters developed a brand new Windows installer using Wise 8.1,
2520 generously donated to us by Wise Solutions.
2521
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002522- configure supports a new option --enable-unicode, with the values
2523 ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
2524 type and supporting code is completely removed from the interpreter.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002525
Jack Jansen32ce0cd2001-08-21 19:28:20 +00002526- A new configure option --enable-framework builds a Mac OS X framework,
2527 which "make frameworkinstall" will install. This provides a starting
2528 point for more mac-like functionality, join pythonmac-sig@python.org
2529 if you are interested in helping.
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002530
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002531- The NeXT platform is no longer supported.
2532
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002533- The 'new' module is now statically linked.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002534
Tim Peters0afb6092001-08-15 06:06:44 +00002535Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002536-----
Tim Peters0afb6092001-08-15 06:06:44 +00002537
2538- The new Tools/scripts/cleanfuture.py can be used to automatically
Andrew M. Kuchlingb0532092001-08-15 15:54:56 +00002539 edit out obsolete future statements from Python source code. See
Tim Peters0afb6092001-08-15 06:06:44 +00002540 the module docstring for details.
2541
Tim Peters20f51a72001-07-21 02:31:40 +00002542Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002543-----
Tim Peters20f51a72001-07-21 02:31:40 +00002544
Tim Peters5e824c32001-08-12 22:25:01 +00002545- regrtest.py now knows which tests are expected to be skipped on some
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002546 platforms, allowing to give clearer test result output. regrtest
2547 also has optional --use/-u switch to run normally disabled tests
2548 which require network access or consume significant disk resources.
Tim Peters5e824c32001-08-12 22:25:01 +00002549
Tim Peters20f51a72001-07-21 02:31:40 +00002550- Several new tests in the standard test suite, with special thanks to
2551 Nick Mathewson.
2552
2553Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002554----
Tim Peters20f51a72001-07-21 02:31:40 +00002555
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002556- The floor division operator // has been added as outlined in PEP
2557 238. The / operator still provides classic division (and will until
2558 Python 3.0) unless "from __future__ import division" is included, in
2559 which case the / operator will provide true division. The operator
2560 module provides truediv() and floordiv() functions. Augmented
2561 assignment variants are included, as are the equivalent overloadable
2562 methods and C API methods. See the PEP for a full discussion:
2563 <http://python.sf.net/peps/pep-0238.html>
2564
Tim Peters6cd6a822001-08-17 22:11:27 +00002565- Future statements are now effective in simulated interactive shells
2566 (like IDLE). This should "just work" by magic, but read Michael
2567 Hudson's "Future statements in simulated shells" PEP 264 for full
2568 details: <http://python.sf.net/peps/pep-0264.html>.
2569
Guido van Rossumf86ddd22001-08-17 21:21:04 +00002570- The type/class unification (PEP 252-253) was integrated into the
2571 trunk and is not so tentative any more (the exact specification of
2572 some features is still tentative). A lot of work has done on fixing
2573 bugs and adding robustness and features (performance still has to
2574 come a long way).
2575
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002576- Warnings about a mismatch in the Python API during extension import
2577 now use the Python warning framework (which makes it possible to
2578 write filters for these warnings).
2579
Barry Warsaw9b3be7f2001-08-14 18:35:02 +00002580- A function's __dict__ (aka func_dict) will now always be a
2581 dictionary. It used to be possible to delete it or set it to None,
2582 but now both actions raise TypeErrors. It is still legal to set it
2583 to a dictionary object. Getting func.__dict__ before any attributes
2584 have been assigned now returns an empty dictionary instead of None.
2585
Guido van Rossum32aa5d22001-09-05 18:43:35 +00002586- A new command line option, -E, was added which disables the use of
2587 all environment variables, or at least those that are specifically
2588 significant to Python. Usually those have a name starting with
2589 "PYTHON". This was used to fix a problem where the tests fail if
2590 the user happens to have PYTHONHOME or PYTHONPATH pointing to an
2591 older distribution.
2592
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002593Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002594-------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002595
Tim Peters5e824c32001-08-12 22:25:01 +00002596- New class Differ and new functions ndiff() and restore() in difflib.py.
2597 These package the algorithms used by the popular Tools/scripts/ndiff.py,
Tim Peters0afb6092001-08-15 06:06:44 +00002598 for programmatic reuse.
Tim Peters5e824c32001-08-12 22:25:01 +00002599
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002600- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
2601 value using the minimal quoting required for the value; more
2602 reliable than using xml.sax.saxutils.escape() for attribute values.
2603
2604- Readline completion support for cmd.Cmd was added.
2605
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002606- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
2607
2608- Added function threading.BoundedSemaphore()
2609
2610- Added Ka-Ping Yee's cgitb.py module.
2611
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002612- The 'new' module now exposes the CO_xxx flags.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002613
Martin v. Löwis560da622001-11-24 09:24:51 +00002614- The gc module offers the get_referents function.
2615
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002616New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002617-------------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002618
2619C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002620-----
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002621
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002622- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
2623 which provide a cross-platform implementations for the
2624 relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
2625 the standard sprintf() and vsprintf() C lib APIs, these versions
2626 apply bounds checking on the used buffer which enhances protection
2627 against buffer overruns.
2628
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002629- Unicode APIs now use name mangling to assure that mixing interpreters
Tim Petersc1731372001-08-04 08:12:36 +00002630 and extensions using different Unicode widths is rendered next to
2631 impossible. Trying to import an incompatible Unicode-aware extension
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002632 will result in an ImportError. Unicode extensions writers must make
2633 sure to check the Unicode width compatibility in their extensions by
2634 using at least one of the mangled Unicode APIs in the extension.
2635
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002636- Two new flags METH_NOARGS and METH_O are available in method definition
2637 tables to simplify implementation of methods with no arguments and a
2638 single untyped argument. Calling such methods is more efficient than
2639 calling corresponding METH_VARARGS methods. METH_OLDARGS is now
2640 deprecated.
2641
Tim Petersc1731372001-08-04 08:12:36 +00002642Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002643-------
Tim Petersc1731372001-08-04 08:12:36 +00002644
2645- "import module" now compiles module.pyw if it exists and nothing else
2646 relevant is found.
2647
Tim Peters20f51a72001-07-21 02:31:40 +00002648
Guido van Rossum55a78992001-07-17 17:22:32 +00002649What's New in Python 2.2a1?
Tim Petersf553f892001-05-01 20:45:31 +00002650===========================
2651
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002652*Release date: 18-Jul-2001*
2653
Tim Petersf553f892001-05-01 20:45:31 +00002654Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002655----
Tim Petersa814db52001-05-14 07:05:58 +00002656
Tim Peters6d6c1a32001-08-02 04:15:00 +00002657- TENTATIVELY, a large amount of code implementing much of what's
2658 described in PEP 252 (Making Types Look More Like Classes) and PEP
2659 253 (Subtyping Built-in Types) was added. This will be released
2660 with Python 2.2a1. Documentation will be provided separately
2661 through http://www.python.org/2.2/. The purpose of releasing this
2662 with Python 2.2a1 is to test backwards compatibility. It is
2663 possible, though not likely, that a decision is made not to release
2664 this code as part of 2.2 final, if any serious backwards
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002665 incompatibilities are found during alpha testing that cannot be
Tim Peters6d6c1a32001-08-02 04:15:00 +00002666 repaired.
2667
Guido van Rossum55a78992001-07-17 17:22:32 +00002668- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +00002669 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +00002670 more 'yield' statements. See PEP 255. Since this adds a new
2671 keyword to the language, this feature must be enabled by including a
2672 future statement: "from __future__ import generators" (see PEP 236).
2673 Generators will become a standard feature in a future release
2674 (probably 2.3). Without this future statement, 'yield' remains an
2675 ordinary identifier, but a warning is issued each time it is used.
2676 (These warnings currently don't conform to the warnings framework of
2677 PEP 230; we intend to fix this in 2.2a2.)
2678
Marc-André Lemburg12e74b32001-05-22 08:58:23 +00002679- The UTF-16 codec was modified to be more RFC compliant. It will now
2680 only remove BOM characters at the start of the string and then
2681 only if running in native mode (UTF-16-LE and -BE won't remove a
2682 leading BMO character).
2683
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002684- Strings now have a new method .decode() to complement the already
2685 existing .encode() method. These two methods provide direct access
2686 to the corresponding decoders and encoders of the registered codecs.
2687
2688 To enhance the usability of the .encode() method, the special
2689 casing of Unicode object return values was dropped (Unicode objects
2690 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +00002691
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002692 Both methods will now return whatever the codec in charge of the
2693 requested encoding returns as object, e.g. Unicode codecs will
2694 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
2695 will return u"äöü"). This enables codec writer to create codecs
2696 for various simple to use conversions.
2697
2698 New codecs were added to demonstrate these new features (the .encode()
2699 and .decode() columns indicate the type of the returned objects):
2700
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002701 +---------+-----------+-----------+-----------------------------+
2702 |Name | .encode() | .decode() | Description |
2703 +=========+===========+===========+=============================+
2704 |uu | string | string | UU codec (e.g. for email) |
2705 +---------+-----------+-----------+-----------------------------+
2706 |base64 | string | string | base64 codec |
2707 +---------+-----------+-----------+-----------------------------+
2708 |quopri | string | string | quoted-printable codec |
2709 +---------+-----------+-----------+-----------------------------+
2710 |zlib | string | string | zlib compression |
2711 +---------+-----------+-----------+-----------------------------+
2712 |hex | string | string | 2-byte hex codec |
2713 +---------+-----------+-----------+-----------------------------+
2714 |rot-13 | string | Unicode | ROT-13 Unicode charmap codec|
2715 +---------+-----------+-----------+-----------------------------+
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002716
Mark Hammond2a0af792001-05-14 03:09:36 +00002717- Some operating systems now support the concept of a default Unicode
2718 encoding for file system operations. Notably, Windows supports 'mbcs'
2719 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002720 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +00002721 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002722
2723 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +00002724 functions that return filenames (such as os.listdir()) to return Python
2725 string objects pre-encoded using the default file system encoding for
2726 the platform. As this encoding is likely to be different from Python's
2727 default encoding, converting this name to a Unicode object before passing
2728 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +00002729 would attempt to use its default encoding (generally ASCII) rather than
2730 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002731
Tim Petersa814db52001-05-14 07:05:58 +00002732 In general, this change simply removes surprises when working with
2733 Unicode and the file system, making these operations work as you expect,
2734 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +00002735 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +00002736
Tim Peters61dff2b2001-05-08 15:43:37 +00002737- Float (and complex) literals in source code were evaluated to full
2738 precision only when running from a .py file; the same code loaded from a
2739 .pyc (or .pyo) file could suffer numeric differences starting at about the
2740 12th significant decimal digit. For example, on a machine with IEEE-754
2741 floating arithmetic,
2742
2743 x = 9007199254740992.0
2744 print long(x)
2745
2746 printed 9007199254740992 if run directly from .py, but 9007199254740000
2747 if from a compiled (.pyc or .pyo) file. This was due to marshal using
2748 str(float) instead of repr(float) when building code objects. marshal
2749 now uses repr(float) instead, which should reproduce floats to full
2750 machine precision (assuming the platform C float<->string I/O conversion
2751 functions are of good quality).
2752
2753 This may cause floating-point results to change in some cases, and
2754 usually for the better, but may also cause numerically unstable
2755 algorithms to break.
2756
Tim Peters2f228e72001-05-13 00:19:31 +00002757- The implementation of dicts suffers fewer collisions, which has speed
2758 benefits. However, the order in which dict entries appear in dict.keys(),
2759 dict.values() and dict.items() may differ from previous releases for a
2760 given dict. Nothing is defined about this order, so no program should
2761 rely on it. Nevertheless, it's easy to write test cases that rely on the
2762 order by accident, typically because of printing the str() or repr() of a
2763 dict to an "expected results" file. See Lib/test/test_support.py's new
2764 sortdict(dict) function for a simple way to display a dict in sorted
2765 order.
2766
Tim Peters7a3bfc32001-06-12 01:22:22 +00002767- Many other small changes to dicts were made, resulting in faster
2768 operation along the most common code paths.
2769
Guido van Rossum10315822001-05-01 20:54:30 +00002770- Dictionary objects now support the "in" operator: "x in dict" means
2771 the same as dict.has_key(x).
2772
Barry Warsaw51acc8d2001-06-26 20:12:50 +00002773- The update() method of dictionaries now accepts generic mapping
2774 objects. Specifically the argument object must support the .keys()
2775 and __getitem__() methods. This allows you to say, for example,
2776 {}.update(UserDict())
2777
Guido van Rossum10315822001-05-01 20:54:30 +00002778- Iterators were added; this is a generalized way of providing values
2779 to a for loop. See PEP 234. There's a new built-in function iter()
2780 to return an iterator. There's a new protocol to get the next value
2781 from an iterator using the next() method (in Python) or the
2782 tp_iternext slot (in C). There's a new protocol to get iterators
2783 using the __iter__() method (in Python) or the tp_iter slot (in C).
2784 Iterating (i.e. a for loop) over a dictionary generates its keys.
2785 Iterating over a file generates its lines.
2786
Tim Petersf553f892001-05-01 20:45:31 +00002787- The following functions were generalized to work nicely with iterator
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002788 arguments::
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002789
Tim Peterse63415e2001-05-08 04:38:29 +00002790 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +00002791 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
2792 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +00002793 join() method of strings
2794 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +00002795 'x in y' and 'x not in y' (PySequence_Contains() in C API)
2796 operator.countOf() (PySequence_Count() in C API)
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002797 right-hand side of assignment statements with multiple targets, such as ::
Tim Petersd6d010b2001-06-21 02:49:55 +00002798 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +00002799
Tim Petersd85e1022001-05-11 21:51:48 +00002800- Accessing module attributes is significantly faster (for example,
2801 random.random or os.path or yourPythonModule.yourAttribute).
2802
Tim Peterse63415e2001-05-08 04:38:29 +00002803- Comparing dictionary objects via == and != is faster, and now works even
2804 if the keys and values don't support comparisons other than ==.
2805
Tim Peters95bf9392001-05-10 08:32:44 +00002806- Comparing dictionaries in ways other than == and != is slower: there were
2807 insecurities in the dict comparison implementation that could cause Python
2808 to crash if the element comparison routines for the dict keys and/or
2809 values mutated the dicts. Making the code bulletproof slowed it down.
2810
Tim Peterseb28ef22001-06-02 05:27:19 +00002811- Collisions in dicts are resolved via a new approach, which can help
2812 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +00002813 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +00002814 faster now. Thanks to Christian Tismer for pointing out the cause and
2815 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +00002816
Tim Peters52e155e2001-06-16 05:42:57 +00002817- repr() is much faster for large containers (dict, list, tuple).
2818
2819
Tim Petersa814db52001-05-14 07:05:58 +00002820Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002821-------
Tim Petersa814db52001-05-14 07:05:58 +00002822
Fred Drake960fdf92001-07-20 18:38:26 +00002823- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002824 were added to the string module. These a locale-independent
Fred Drake960fdf92001-07-20 18:38:26 +00002825 constants, unlike letters, lowercase, and uppercase. These are now
2826 use in appropriate locations in the standard library.
2827
Martin v. Löwisf0473d52001-07-18 16:17:16 +00002828- The flags used in dlopen calls can now be configured using
2829 sys.setdlopenflags and queried using sys.getdlopenflags.
2830
Guido van Rossumc7e4aca2001-07-12 11:54:37 +00002831- Fredrik Lundh's xmlrpclib is now a standard library module. This
2832 provides full client-side XML-RPC support. In addition,
2833 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
2834 one asyncore-based). Thanks to Eric Raymond for the documentation.
2835
Guido van Rossum643d3912001-07-05 14:46:25 +00002836- The xrange() object is simplified: it no longer supports slicing,
2837 repetition, comparisons, efficient 'in' checking, the tolist()
2838 method, or the start, stop and step attributes. See PEP 260.
2839
Martin v. Löwisebf94db2001-06-06 06:25:40 +00002840- A new function fnmatch.filter to filter lists of file names was added.
2841
Barry Warsawffd674d2001-05-22 16:00:10 +00002842- calendar.py uses month and day names based on the current locale.
2843
Guido van Rossum2e0a6542001-05-15 02:14:44 +00002844- strop is now *really* obsolete (this was announced before with 1.6),
2845 and issues DeprecationWarning when used (except for the four items
2846 that are still imported into string.py).
2847
Tim Petersa814db52001-05-14 07:05:58 +00002848- Cookie.py now sorts key+value pairs by key in output strings.
2849
2850- pprint.isrecursive(object) didn't correctly identify recursive objects.
2851 Now it does.
2852
Tim Peters95b3f782001-05-14 18:39:41 +00002853- pprint functions now much faster for large containers (tuple, list, dict).
2854
Tim Peters7b9542a2001-06-10 23:40:19 +00002855- New 'q' and 'Q' format codes in the struct module, corresponding to C
2856 types "long long" and "unsigned long long" (on Windows, __int64). In
2857 native mode, these can be used only when the platform C compiler supports
2858 these types (when HAVE_LONG_LONG is #define'd by the Python config
2859 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +00002860 In standard mode, 'q' and 'Q' are supported on all platforms, and are
2861 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +00002862
Guido van Rossum83213cc2001-06-12 16:48:52 +00002863- The site module installs a new built-in function 'help' that invokes
2864 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
2865 it displays a message reminding the user to use 'help()' or
2866 'help(object)'.
2867
Tim Petersa814db52001-05-14 07:05:58 +00002868Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002869-----
Tim Petersa814db52001-05-14 07:05:58 +00002870
2871- New test_mutants.py runs dict comparisons where the key and value
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002872 comparison operators mutate the dicts randomly during comparison. This
Tim Petersa814db52001-05-14 07:05:58 +00002873 rapidly causes Python to crash under earlier releases (not for the faint
2874 of heart: it can also cause Win9x to freeze or reboot!).
2875
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002876- New test_pprint.py verifies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +00002877 pprint.isreadable() return sensible results. Also verifies that simple
2878 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +00002879
Tim Peters4324aa32001-05-28 22:30:08 +00002880C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002881-----
Tim Peters4324aa32001-05-28 22:30:08 +00002882
2883- Removed the unused last_is_sticky argument from the internal
2884 _PyTuple_Resize(). If this affects you, you were cheating.
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002885
2886----
2887
2888**(For information about older versions, consult the HISTORY file.)**