blob: ff1e44d4cf6de223dc222af9709943fc9147cc34 [file] [log] [blame]
Tim Petersaf8446f2001-12-21 21:36:50 +00001What's New in Python 2.3 alpha 1?
2XXX Release date: DD-MMM-2002 XXX
3=================================
4
5Type/class unification and new-style classes
6
7Core and builtins
8
Guido van Rossum9562bcf2002-06-14 21:31:18 +00009- The built-ins slice() and buffer() are now callable types. The
10 types classobj (formerly class), code, function, instance, and
11 instancemethod (formerly instance-method), which have no built-in
12 names but are accessible through the types module, are now also
13 callable. The type dict-proxy is renamed to dictproxy.
14
Neal Norwitz1f68fc72002-06-14 00:50:42 +000015- Fixed string.startswith and string.endswith builtin methods
16 so they accept negative indices. [SF bug 493951]
17
Guido van Rossumc5fe5eb2002-06-12 03:45:21 +000018- Fixed a bug with a continue inside a try block and a yield in the
19 finally clause. [SF bug 567538]
20
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +000021- Most builtin sequences now support "extended slices", i.e. slices
Guido van Rossum2e82e712002-06-13 11:41:07 +000022 with a third "stride" parameter. For example, "hello world"[::-1]
23 gives "dlrow olleh".
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +000024
Guido van Rossum9f7549b2002-06-10 21:39:42 +000025- Cycles going through the __class__ link of a new-style instance are
26 now detected by the garbage collector.
27
Guido van Rossum9923ffe2002-06-04 19:52:53 +000028- Classes using __slots__ are now properly garbage collected.
29 [SF bug 519621]
30
31- Tightened the __slots__ rules: a slot name must be a valid Python
32 identifier.
33
Guido van Rossum2e4e0262002-06-04 05:58:34 +000034- The constructor for the module type now requires a name argument and
35 takes an optional docstring argument. Previously, this constructor
36 ignored its arguments. As a consequence, deriving a class from a
37 module (not from the module type) is now illegal; previously this
38 created an unnamed module, just like invoking the module type did.
39 [SF bug 563060]
40
Neal Norwitzd68f5172002-05-29 15:54:55 +000041- A new warning PendingDeprecationWarning was added to provide
42 direction on features which are in the process of being deprecated.
43 The warning will not be printed by default. To see the pending
44 deprecations, use -Walways::PendingDeprecationWarning::
45 as a command line option or warnings.filterwarnings() in code.
46
Neal Norwitz32a7e7f2002-05-31 19:58:02 +000047- A new type object, 'basestring', is added. This is a common base type
Guido van Rossumcacfc072002-05-24 19:01:59 +000048 for 'str' and 'unicode', and can be used instead of
49 types.StringTypes, e.g. to test whether something is "a string":
Neal Norwitz32a7e7f2002-05-31 19:58:02 +000050 isinstance(x, basestring) is True for Unicode and 8-bit strings. This
Guido van Rossumcacfc072002-05-24 19:01:59 +000051 is an abstract base class and cannot be instantiated directly.
52
Fred Draked0ba6362002-05-02 21:28:26 +000053- Deprecated features of xrange objects have been removed as
54 promised. The start, stop, and step attributes and the tolist()
55 method no longer exist. xrange repetition and slicing have been
56 removed.
57
Guido van Rossum7dab2422002-04-26 19:40:56 +000058- New builtin function enumerate(x), from PEP 279. Example:
59 enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
60 The argument can be an arbitrary iterable object.
61
Neil Schemenauer89e3ee02002-04-26 01:58:53 +000062- The assert statement no longer tests __debug__ at runtime. This means
63 that assert statements cannot be disabled by assigning a false value
64 to __debug__.
65
Walter Dörwald068325e2002-04-15 13:36:47 +000066- A method zfill() was added to str and unicode, that fills a numeric
67 string to the left with zeros. For example,
68 "+123".zfill(6) -> "+00123".
69
Guido van Rossum862fe3c2002-04-15 12:36:47 +000070- Complex numbers supported divmod() and the // and % operators, but
71 these make no sense. Since this was documented, they're being
72 deprecated now.
73
Guido van Rossum26dd8302002-04-26 20:11:29 +000074- String and unicode methods lstrip(), rstrip() and strip() now take
75 an optional argument that specifies the characters to strip. For
76 example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
Guido van Rossum49042042002-04-13 00:59:05 +000077
Guido van Rossumc69343b2002-04-12 19:22:48 +000078- Added a new dict method pop(key). This removes and returns the
79 value corresponding to key. [SF patch #539949]
80
Guido van Rossum8ace1ab2002-04-06 01:05:01 +000081- Changed new-style class instantiation so that when C's __new__
82 method returns something that's not a C instance, its __init__ is
83 not called. [SF bug #537450]
84
Guido van Rossum181e41a2002-04-06 00:23:25 +000085- Fixed super() to work correctly with class methods. [SF bug #535444]
86
Guido van Rossum47834462002-04-04 15:21:33 +000087- A new built-in type, bool, has been added, as well as built-in
88 names for its two values, True and False. Comparisons and sundry
89 other operations that return a truth value have been changed to
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +000090 return a bool instead. Read PEP 285 for an explanation of why this
Guido van Rossum47834462002-04-04 15:21:33 +000091 is backward compatible.
92
Guido van Rossum95b62a62002-03-29 01:07:24 +000093- Fixed two bugs reported as SF #535905: under certain conditions,
94 deallocating a deeply nested structure could cause a segfault in the
95 garbage collector, due to interaction with the "trashcan" code;
96 access to the current frame during destruction of a local variable
97 could access a pointer to freed memory.
98
Neil Schemenauer9d50d132002-03-22 17:06:59 +000099- The optional object allocator has been enabled by default.
100
Guido van Rossum8c842552002-03-14 23:05:54 +0000101- If you try to pickle an instance of a class that has __slots__ but
102 doesn't define or override __getstate__, a TypeError is now raised.
103 This is done by adding a bozo __getstate__ to the class that always
104 raises TypeError. (Before, this would appear to be pickled, but the
105 state of the slots would be lost.)
106
Martin v. Löwiscfeb3b62002-03-03 21:30:27 +0000107- PyErr_Display will provide file and line information for all exceptions
108 that have an attribute print_file_and_line, not just SyntaxErrors.
109
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000110- The UTF-8 codec will now encode and decode Unicode surrogates
111 correctly and without raising exceptions for unpaired ones.
112
Neal Norwitz649b7592002-01-01 19:07:13 +0000113- file.xreadlines() now raises a ValueError if the file is closed:
114 Previously, an xreadlines object was returned which would raise
115 a ValueError when the xreadlines.next() method was called.
116
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000117- sys.exit() inadvertently allowed more than one argument.
Neal Norwitz0c766a02002-03-27 13:03:09 +0000118 An exception will now be raised if more than one argument is used.
119
Tim Petersaf8446f2001-12-21 21:36:50 +0000120Extension modules
121
Guido van Rossum9562bcf2002-06-14 21:31:18 +0000122- The 'new' module is no longer an extension, but a Python module that
123 only exists for backwards compatibility. Its contents are no longer
124 functions but callable type objects.
125
Tim Peters81b92512002-04-29 01:37:32 +0000126- The bsddb.*open functions can now take 'None' as a filename.
Anthony Baxter83888952002-04-23 02:11:05 +0000127 This will create a temporary in-memory bsddb that won't be
Tim Peters81b92512002-04-29 01:37:32 +0000128 written to disk.
Anthony Baxter83888952002-04-23 02:11:05 +0000129
Martin v. Löwis606edc12002-06-13 21:09:11 +0000130- posix.killpg, posix.mknod, and posix.getpgid have been added where
131 available.
Martin v. Löwis06a83e92002-04-14 10:19:44 +0000132
Martin v. Löwis2e64c342002-03-27 18:49:02 +0000133- The locale module now exposes the C library's gettext interface.
134
Tim Petersfbf74f22002-03-14 19:06:01 +0000135- A security hole ("double free") was found in zlib-1.1.3, a popular
136 third party compression library used by some Python modules. The
137 hole was quickly plugged in zlib-1.1.4, and the Windows build of
138 Python now ships with zlib-1.1.4.
139
Martin v. Löwis688357e2002-04-08 21:28:20 +0000140- pwd, grp, and resource return enhanced tuples now, with symbolic
141 field names.
Martin v. Löwis29001ff2002-03-01 10:47:37 +0000142
Martin v. Löwis99866332002-03-01 10:27:01 +0000143- array.array is now a type object. A new format character
144 'u' indicates Py_UNICODE arrays. For those, .tounicode and
145 .fromunicode methods are available. Arrays now support __iadd__
146 and __imul__.
147
Neal Norwitze790eae2002-01-01 21:14:12 +0000148- dl now builds on every system that has dlfcn.h. Failure in case
Martin v. Löwis93227272002-01-01 20:18:30 +0000149 of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
150 is called.
151
Michael W. Hudson34f20ea2002-05-27 15:08:24 +0000152- signal.sigpending, signal.sigprocmask and signal.sigsuspend have
153 been added where available.
154
Tim Petersaf8446f2001-12-21 21:36:50 +0000155Library
156
Guido van Rossum9f7549b2002-06-10 21:39:42 +0000157- Some fixes in the copy module: when an object is copied through its
158 __reduce__ method, there was no check for a __setstate__ method on
159 the result [SF patch 565085]; deepcopy should treat instances of
160 custom metaclasses the same way it treats instances of type 'type'
161 [SF patch 560794].
162
Guido van Rossum5033c8e2002-06-07 12:40:52 +0000163- Sockets now support timeout mode. After s.settimeout(T), where T is
164 a float expressing seconds, subsequent operations raise an exception
165 if they cannot be completed within T seconds. To disable timeout
166 mode, use s.settimeout(None).
167
168- getopt.gnu_getopt was added. This supports GNU-style option
169 processing, where options can be mixed with non-option arguments.
Martin v. Löwis446a25f2002-06-06 10:58:36 +0000170
Michael W. Hudsonb0dc1a32002-06-04 18:27:35 +0000171- Stop using strings for exceptions. String objects used for
172 exceptions are now classes deriving from Exception. The objects
173 changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
174 tabnanny.NannyNag, and xdrlib.Error.
Neal Norwitzb5b5a262002-06-04 17:14:07 +0000175
Walter Dörwald474458d2002-06-04 15:16:29 +0000176- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
177 BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
178 Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
179 big endian systems were added to the codecs module. The old names
180 BOM32_* and BOM64_* were off by a factor of 2.
181
Raymond Hettinger87f59ee2002-05-13 04:17:32 +0000182- added degree/radian conversion functions to the math module.
183
Raymond Hettinger9b1df1d2002-05-12 06:07:21 +0000184- ftplib.retrlines() now tests for callback is None rather than testing
185 for False. Was causing an error when given a callback object which
186 was callable but also returned len() as zero. The change may
187 create new breakage if the caller relied on the undocumented behavior
188 and called with callback set to [] or some other False value not
189 identical to None.
190
Tim Peters46c04e12002-05-05 20:40:00 +0000191- random.gauss() uses a piece of hidden state used by nothing else,
192 and the .seed() and .whseed() methods failed to reset it. In other
193 words, setting the seed didn't completely determine the sequence of
194 results produced by random.gauss(). It does now. Programs repeatedly
195 mixing calls to a seed method with calls to gauss() may see different
196 results now.
197
Fred Drake7f781c92002-05-01 20:33:53 +0000198- The pickle.Pickler class grew a clear_memo() method to mimic that
199 provided by cPickle.Pickler.
200
Tim Peters81b92512002-04-29 01:37:32 +0000201- difflib's SequenceMatcher class now does a dynamic analysis of
202 which elements are so frequent as to constitute noise. For
203 comparing files as sequences of lines, this generally works better
204 than the IS_LINE_JUNK function, and function ndiff's linejunk
205 argument defaults to None now as a result. A happy benefit is
206 that SequenceMatcher may run much faster now when applied
207 to large files with many duplicate lines (for example, C program
208 text with lots of repeated "}" and "return NULL;" lines).
209
Guido van Rossum256705b2002-04-23 13:29:43 +0000210- New Text.dump() method in Tkinter module.
211
Marc-André Lemburg1ec71ea2002-04-17 20:33:40 +0000212- New distutils commands for building packagers were added to
213 support pkgtool on Solaris and swinstall on HP-UX.
214
215- distutils now has a new abstract binary packager base class
216 command/bdist_packager, which simplifies writing packagers.
217 This will hopefully provide the missing bits to encourage
218 people to submit more packagers, e.g. for Debian, FreeBSD
219 and other systems.
220
Marc-André Lemburg4179a012002-04-05 12:15:05 +0000221- The UTF-16, -LE and -BE now raise a NotImplementedError
222 for all calls to .readline(). Previously, they used to just
223 produce garbage or fail with an encoding error -- UTF-16 is
224 a 2-byte encoding and the C lib's line reading APIs don't
225 work well with these.
226
Martin v. Löwis5c137c22002-03-18 12:44:08 +0000227- compileall now supports quiet operation.
228
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000229- The BaseHTTPServer now implements optional HTTP/1.1 persistent
Martin v. Löwis587c98c2002-03-17 18:37:22 +0000230 connections.
231
Marc-André Lemburga5d2b4c2002-02-16 18:23:30 +0000232- socket module: the SSL support was broken out of the main
233 _socket module C helper and placed into a new _ssl helper
234 which now gets imported by socket.py if available and working.
235
Marc-André Lemburg37aa5802002-02-10 21:42:47 +0000236- encodings package: added aliases for all supported IANA character
237 sets
238
Guido van Rossum606fe4e2001-12-28 20:57:14 +0000239- ftplib: to safeguard the user's privacy, anonymous login will use
240 "anonymous@" as default password, rather than the real user and host
241 name.
242
Fred Drake36736122002-01-10 13:50:31 +0000243- webbrowser: tightened up the command passed to os.system() so that
244 arbitrary shell code can't be executed because a bogus URL was
245 passed in.
246
Tim Peters11bd9942002-02-01 00:52:29 +0000247- gettext.translation has an optional fallback argument, and
Martin v. Löwisa55ffae2002-01-11 06:58:49 +0000248 gettext.find an optional all argument. Translations will now fallback
249 on a per-message basis.
Martin v. Löwis1be64192002-01-11 06:33:28 +0000250
Martin v. Löwis9668b932002-01-12 11:27:42 +0000251- distutils bdist commands now offer a --skip-build option.
252
Walter Dörwaldb25c2b02002-03-21 10:38:40 +0000253- warnings.warn now accepts a Warning instance as first argument.
254
Fred Drakefed7e852002-04-04 19:36:15 +0000255- The xml.sax.expatreader.ExpatParser class will no longer create
256 circular references by using itself as the locator that gets passed
257 to the content handler implementation. [SF bug #535474]
258
Barry Warsaw47f3e2c2002-05-20 00:14:24 +0000259- The email.Parser.Parser class now properly parses strings regardless
260 of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
261 or CRLF). Also, the Header class's constructor default arguments
262 has changed slightly so that an explicit maxlinelen value is always
263 honored.
264
Tim Petersaf8446f2001-12-21 21:36:50 +0000265Tools/Demos
266
Marc-André Lemburg46260092002-04-04 16:17:11 +0000267- freeze.py now produces binaries which can import shared modules,
268 unlike before when this failed due to missing symbol exports in
269 the generated binary.
270
Tim Petersaf8446f2001-12-21 21:36:50 +0000271Build
272
Martin v. Löwisa3fb4f72002-06-09 13:33:54 +0000273- The configure option --without-doc-strings can be used to remove the
274 doc strings from the builtin functions and modules; this reduces the
275 size of the executable.
276
Tim Peters639295f2002-04-21 07:30:30 +0000277- XXX WITH_UNIVERSAL_NEWLINES Somebody fill this in; the PEP doesn't
278 say how or when to configure it, or how to turn it off.
279
Martin v. Löwis1142de32002-03-29 16:28:31 +0000280- On Unix, a shared libpython2.3.so can be created with --enable-shared.
281
Tim Peters8deda702002-03-30 10:06:07 +0000282- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
283 preprocessor symbols were eliminated. The internal decisions they
284 controlled stopped being experimental long ago.
Tim Peters1f7df352002-03-29 03:29:08 +0000285
Fred Drake7d28b732002-05-02 21:17:00 +0000286- The tools used to build the documentation now work under Cygwin as
287 well as Unix.
288
Skip Montanaro57454e52002-06-14 20:30:31 +0000289- The bsddb and dbm module builds have been changed to try and avoid version
290 skew problems and disable linkage with Berkeley DB 1.85 unless the
291 installer knows what s/he's doing. See the section on building these
292 modules in the README file for details.
293
Tim Petersaf8446f2001-12-21 21:36:50 +0000294C API
295
Martin v. Löwis01f94bd2002-05-08 08:44:21 +0000296- Added new macro PySequence_ITEM(o, i) that directly calls
297 sq_item without rechecking that o is a sequence and without
298 adjusting for negative indices.
299
Fred Draked0ba6362002-05-02 21:28:26 +0000300- PyRange_New() now raises ValueError if the fourth argument is not 1.
301 This is part of the removal of deprecated features of the xrange
302 object.
303
Guido van Rossum517c7d42002-04-26 02:49:14 +0000304- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
305 coercion if both arguments have the same type but this type has the
306 CHECKTYPES flag set. This is to better support proxies.
307
Neil Schemenauer9344b142002-04-12 23:00:08 +0000308- The type of tp_free has been changed from "void (*)(PyObject *)" to
309 "void (*)(void *)".
310
311- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
312
Guido van Rossum0986d822002-04-08 01:38:42 +0000313- A type can now inherit its metatype from its base type. Previously,
314 when PyType_Ready() was called, if ob_type was found to be NULL, it
315 was always set to &PyType_Type; now it is set to base->ob_type,
316 where base is tp_base, defaulting to &PyObject_Type.
317
318- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
319
Neil Schemenauerc9abc1d2002-05-08 14:14:41 +0000320- The PyCore_* family of APIs have been removed.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000321
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000322- The "u#" parser marker will now pass through Unicode objects as-is
Marc-André Lemburg3e3eacb2002-01-09 16:21:27 +0000323 without going through the buffer API.
324
Martin v. Löwis7198a522002-01-01 19:59:11 +0000325- The enumerators of cmp_op have been renamed to use the prefix PyCmp_.
326
Tim Peters10a3bb52001-12-25 19:07:38 +0000327- An old #define of ANY as void has been removed from pyport.h. This
328 hasn't been used since Python's pre-ANSI days, and the #define has
329 been marked as obsolete since then. SF bug 495548 says it created
330 conflicts with other packages, so keeping it around wasn't harmless.
331
Tim Petersaf8446f2001-12-21 21:36:50 +0000332- Because Python's magic number scheme broke on January 1st, we decided
333 to stop Python development. Thanks for all the fish!
334
Tim Petersfb05db22002-03-11 00:24:00 +0000335- Some of us don't like fish, so we changed Python's magic number
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000336 scheme to a new one. See Python/import.c for details.
337
Tim Petersaf8446f2001-12-21 21:36:50 +0000338New platforms
339
Martin v. Löwisf90ae202002-06-11 06:22:31 +0000340- AtheOS is now supported.
341
Martin v. Löwisa6e97582002-01-01 18:41:33 +0000342- GNU/Hurd is now supported.
343
Tim Petersaf8446f2001-12-21 21:36:50 +0000344Tests
345
346Windows
347
Tim Peters08e72952002-04-16 20:48:01 +0000348- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
349 of that has been fixed in the installer (disabled Wise's "delete in-
350 use files" uninstall option).
351
Guido van Rossum181e41a2002-04-06 00:23:25 +0000352- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
353
Tim Peters33187922002-04-04 20:02:04 +0000354- The installer now installs Start menu shortcuts under (the local
355 equivalent of) "All Users" when doing an Admin install.
356
Tim Petersfb05db22002-03-11 00:24:00 +0000357- file.truncate([newsize]) now works on Windows for all newsize values.
358 It used to fail if newsize didn't fit in 32 bits, reflecting a
359 limitation of MS _chsize (which is no longer used).
360
Tim Petersab034fa2002-02-01 11:27:43 +0000361- os.waitpid() is now implemented for Windows, and can be used to block
362 until a specified process exits. This is similar to, but not exactly
363 the same as, os.waitpid() on POSIX systems. If you're waiting for
364 a specific process whose pid was obtained from one of the spawn()
365 functions, the same Python os.waitpid() code works across platforms.
Tim Peters33187922002-04-04 20:02:04 +0000366 See the docs for details. The docs were changed to clarify that
367 spawn functions return, and waitpid requires, a process handle on
368 Windows (not the same thing as a Windows process id).
Tim Petersab034fa2002-02-01 11:27:43 +0000369
Tim Peters11bd9942002-02-01 00:52:29 +0000370- New tempfile.TemporaryFile implementation for Windows: this doesn't
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000371 need a TemporaryFileWrapper wrapper anymore, and should be immune
Tim Peters11bd9942002-02-01 00:52:29 +0000372 to a nasty problem: before 2.3, if you got a temp file on Windows, it
373 got wrapped in an object whose close() method first closed the
374 underlying file, then deleted the file. This usually worked fine.
375 However, the spawn family of functions on Windows create (at a low C
376 level) the same set of open files in the spawned process Q as were
377 open in the spawning process P. If a temp file f was among them, then
378 doing f.close() in P first closed P's C-level file handle on f, but Q's
379 C-level file handle on f remained open, so the attempt in P to delete f
380 blew up with a "Permission denied" error (Windows doesn't allow
381 deleting open files). This was surprising, subtle, and difficult to
382 work around.
383
384- The os module now exports all the symbolic constants usable with the
385 low-level os.open() on Windows: the new constants in 2.3 are
386 O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
387 The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
388 O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
389 to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
390 (so specify both if you want both; note that neither is useful unless
391 specified with O_CREAT too).
392
Tim Petersaf8446f2001-12-21 21:36:50 +0000393Mac
394
395
Tim Peters909c0912001-12-14 23:16:18 +0000396What's New in Python 2.2 final?
397Release date: 21-Dec-2001
398===============================
399
400Type/class unification and new-style classes
401
Barry Warsaw52acb492001-12-21 20:04:22 +0000402- pickle.py, cPickle: allow pickling instances of new-style classes
403 with a custom metaclass.
404
Tim Peters909c0912001-12-14 23:16:18 +0000405Core and builtins
406
Barry Warsaw52acb492001-12-21 20:04:22 +0000407- weakref proxy object: when comparing, unwrap both arguments if both
408 are proxies.
409
Tim Peters909c0912001-12-14 23:16:18 +0000410Extension modules
411
Barry Warsaw52acb492001-12-21 20:04:22 +0000412- binascii.b2a_base64(): fix a potential buffer overrun when encoding
413 very short strings.
414
415- cPickle: the obscure "fast" mode was suspected of causing stack
416 overflows on the Mac. Hopefully fixed this by setting the recursion
417 limit much smaller. If the limit is too low (it only affects
418 performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
419 when compiling cPickle.c (or in pyconfig.h).
420
Tim Peters909c0912001-12-14 23:16:18 +0000421Library
422
Barry Warsaw52acb492001-12-21 20:04:22 +0000423- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
424 close or delete time).
425
426- rfc822.py: fixed a bug where the address '<>' was converted to None
427 instead of an empty string (also fixes the email.Utils module).
428
429- xmlrpclib.py: version 1.0.0; uses precision for doubles.
430
431- test suite: the pickle and cPickle tests were not executing any code
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000432 when run from the standard regression test.
Barry Warsaw52acb492001-12-21 20:04:22 +0000433
Tim Peters909c0912001-12-14 23:16:18 +0000434Tools/Demos
435
436Build
437
438C API
439
440New platforms
441
442Tests
443
444Windows
445
Barry Warsaw52acb492001-12-21 20:04:22 +0000446- distutils package: fixed broken Windows installers (bdist_wininst).
447
448- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
449 instances are deleted at process exit time.
450
451- socket.py: prevent mysterious warnings when socket instances are
452 deleted at process exit time.
453
454- posixmodule.c: fix a Windows crash with stat() of a filename ending
455 in backslash.
456
Tim Peters909c0912001-12-14 23:16:18 +0000457Mac
458
Barry Warsaw52acb492001-12-21 20:04:22 +0000459- The Carbon toolbox modules have been upgraded to Universal Headers
460 3.4, and experimental CoreGraphics and CarbonEvents modules have
461 been added. All only for framework-enabled MacOSX.
462
Tim Peters909c0912001-12-14 23:16:18 +0000463
Tim Peters6272dfd2001-12-13 19:34:00 +0000464What's New in Python 2.2c1?
465Release date: 14-Dec-2001
Tim Petersb3c9af12001-11-17 00:21:57 +0000466===========================
467
468Type/class unification and new-style classes
469
Barry Warsaw06557452001-12-14 20:47:12 +0000470- Guido's tutorial introduction to the new type/class features has
471 been extensively updated. See
472
473 http://www.python.org/2.2/descrintro.html
474
475 That remains the primary documentation in this area.
476
Guido van Rossum33bab012001-12-05 22:45:48 +0000477- Fixed a leak: instance variables declared with __slots__ were never
478 deleted!
479
Guido van Rossum4b800852001-12-03 00:54:52 +0000480- The "delete attribute" method of descriptor objects is called
481 __delete__, not __del__. In previous releases, it was mistakenly
482 called __del__, which created an unfortunate overloading condition
483 with finalizers. (The "get attribute" and "set attribute" methods
484 are still called __get__ and __set__, respectively.)
485
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +0000486- Some subtle issues with the super built-in were fixed:
487
488 (a) When super itself is subclassed, its __get__ method would still
489 return an instance of the base class (i.e., of super).
490
491 (b) super(C, C()).__class__ would return C rather than super. This
492 is confusing. To fix this, I decided to change the semantics of
493 super so that it only applies to code attributes, not to data
494 attributes. After all, overriding data attributes is not
495 supported anyway.
496
497 (c) The __get__ method didn't check whether the argument was an
498 instance of the type used in creation of the super instance.
499
Guido van Rossumcd7b7d62001-12-04 21:02:07 +0000500- Previously, hash() of an instance of a subclass of a mutable type
501 (list or dictionary) would return some value, rather than raising
502 TypeError. This has been fixed. Also, directly calling
503 dict.__hash__ and list.__hash__ now raises the same TypeError
504 (previously, these were the same as object.__hash__).
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +0000505
Guido van Rossumd331cb52001-12-05 19:46:42 +0000506- New-style objects now support deleting their __dict__. This is for
507 all intents and purposes equivalent to assigning a brand new empty
508 dictionary, but saves space if the object is not used further.
509
Tim Petersb3c9af12001-11-17 00:21:57 +0000510Core and builtins
511
Tim Peters3caca232001-12-06 06:23:26 +0000512- -Qnew now works as documented in PEP 238: when -Qnew is passed on
513 the command line, all occurrences of "/" use true division instead
514 of classic division. See the PEP for details. Note that "all"
515 means all instances in library and 3rd-party modules, as well as in
516 your own code. As the PEP says, -Qnew is intended for use only in
517 educational environments with control over the libraries in use.
Tim Petersbf72fe22001-12-11 21:43:14 +0000518 Note that test_coercion.py in the standard Python test suite fails
519 under -Qnew; this is expected, and won't be repaired until true
520 division becomes the default (in the meantime, test_coercion is
521 testing the current rules).
Tim Peters3caca232001-12-06 06:23:26 +0000522
Fred Drake6c01e252001-12-14 17:08:12 +0000523- complex() now only allows the first argument to be a string
524 argument, and raises TypeError if either the second arg is a string
525 or if the second arg is specified when the first is a string.
526
Tim Petersb3c9af12001-11-17 00:21:57 +0000527Extension modules
528
Martin v. Löwis560da622001-11-24 09:24:51 +0000529- gc.get_referents was renamed to gc.get_referrers.
530
Tim Petersb3c9af12001-11-17 00:21:57 +0000531Library
532
Tim Peters25059d32001-12-07 20:35:43 +0000533- Functions in the os.spawn() family now release the global interpreter
534 lock around calling the platform spawn. They should always have done
535 this, but did not before 2.2c1. Multithreaded programs calling
536 an os.spawn function with P_WAIT will no longer block all Python threads
537 until the spawned program completes. It's possible that some programs
538 relies on blocking, although more likely by accident than by design.
539
Martin v. Löwis3a89b2b2001-11-25 14:35:58 +0000540- webbrowser defaults to netscape.exe on OS/2 now.
541
Martin v. Löwis652e1912001-11-25 14:50:56 +0000542- Tix.ResizeHandle exposes detach_widget, hide, and show.
543
Martin v. Löwis714d2e22001-12-02 12:26:03 +0000544- The charset alias windows_1252 has been added.
545
Barry Warsaw06557452001-12-14 20:47:12 +0000546- types.StringTypes is a tuple containing the defined string types;
547 usually this will be (str, unicode), but if Python was compiled
548 without Unicode support it will be just (str,).
549
550- The pulldom and minidom modules were synchronized to PyXML.
551
Tim Petersb3c9af12001-11-17 00:21:57 +0000552Tools/Demos
553
Barry Warsaw06557452001-12-14 20:47:12 +0000554- A new script called Tools/scripts/google.py was added, which fires
555 off a search on Google.
556
Tim Petersb3c9af12001-11-17 00:21:57 +0000557Build
558
Barry Warsaw06557452001-12-14 20:47:12 +0000559- Note that release builds of Python should arrange to define the
560 preprocessor symbol NDEBUG on the command line (or equivalent).
561 In the 2.2 pre-release series we tried to define this by magic in
562 Python.h instead, but it proved to cause problems for extension
563 authors. The Unix, Windows and Mac builds now all define NDEBUG in
564 release builds via cmdline (or equivalent) instead. Ports to
565 other platforms should do likewise.
566
Jack Jansen1999ef42001-12-06 21:47:20 +0000567- It is no longer necessary to use --with-suffix when building on a
568 case-insensitive file system (such as Mac OS X HFS+). In the build
569 directory an extension is used, but not in the installed python.
570
Tim Petersb3c9af12001-11-17 00:21:57 +0000571C API
572
Tim Petersf582b822001-12-11 18:51:08 +0000573- New function PyDict_MergeFromSeq2() exposes the builtin dict
574 constructor's logic for updating a dictionary from an iterable object
575 producing key-value pairs.
576
Tim Peterscffed4b2001-11-29 03:26:37 +0000577- PyArg_ParseTupleAndKeywords() requires that the number of entries in
Tim Petersf582b822001-12-11 18:51:08 +0000578 the keyword list equal the number of argument specifiers. This
Tim Peterscffed4b2001-11-29 03:26:37 +0000579 wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
580 dump core in some bad cases. This has been repaired. As a result,
581 PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
582 previously went unchallenged.
583
Tim Petersb3c9af12001-11-17 00:21:57 +0000584New platforms
585
586Tests
587
588Windows
589
590Mac
591
Jack Jansenffa260f2001-12-06 21:14:00 +0000592- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
593 without any trailing digits.
Tim Petersb3c9af12001-11-17 00:21:57 +0000594
Barry Warsaw06557452001-12-14 20:47:12 +0000595- Changed logic for finding python home in Mac OS X framework Pythons.
596 Now sys.executable points to the executable again, in stead of to
597 the shared library. The latter is used only for locating the python
598 home.
599
600
Tim Peters84362bc2001-10-19 17:55:30 +0000601What's New in Python 2.2b2?
Tim Peters76f7fe32001-11-15 20:02:21 +0000602Release date: 16-Nov-2001
Tim Peters84362bc2001-10-19 17:55:30 +0000603===========================
604
605Type/class unification and new-style classes
606
Guido van Rossum3d27df02001-11-15 20:27:54 +0000607- Multiple inheritance mixing new-style and classic classes in the
608 list of base classes is now allowed, so this works now:
Tim Peters76f7fe32001-11-15 20:02:21 +0000609
610 class Classic: pass
Guido van Rossum3d27df02001-11-15 20:27:54 +0000611 class Mixed(Classic, object): pass
Tim Peters76f7fe32001-11-15 20:02:21 +0000612
613 The MRO (method resolution order) for each base class is respected
614 according to its kind, but the MRO for the derived class is computed
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000615 using new-style MRO rules if any base class is a new-style class.
Tim Peters76f7fe32001-11-15 20:02:21 +0000616 This needs to be documented.
617
Tim Petersa427a2b2001-10-29 22:25:45 +0000618- The new builtin dictionary() constructor, and dictionary type, have
619 been renamed to dict. This reflects a decade of common usage.
620
Guido van Rossum3fc08d22001-11-15 20:33:10 +0000621- dict() now accepts an iterable object producing 2-sequences. For
622 example, dict(d.items()) == d for any dictionary d. The argument,
623 and the elements of the argument, can be any iterable objects.
624
Guido van Rossum7ad2d1e2001-10-29 22:11:00 +0000625- New-style classes can now have a __del__ method, which is called
626 when the instance is deleted (just like for classic classes).
627
Guido van Rossum12d955c2001-10-26 14:56:06 +0000628- Assignment to object.__dict__ is now possible, for objects that are
629 instances of new-style classes that have a __dict__ (unless the base
630 class forbids it).
631
Guido van Rossumc8e56452001-10-22 00:43:43 +0000632- Methods of built-in types now properly check for keyword arguments
633 (formerly these were silently ignored). The only built-in methods
634 that take keyword arguments are __call__, __init__ and __new__.
635
Guido van Rossum86443212001-10-27 22:28:54 +0000636- The socket function has been converted to a type; see below.
637
Tim Peters84362bc2001-10-19 17:55:30 +0000638Core and builtins
639
Jeremy Hylton249aaed2001-11-09 21:06:24 +0000640- Assignment to __debug__ raises SyntaxError at compile-time. This
641 was promised when 2.1c1 was released as "What's New in Python 2.1c1"
Barry Warsaw012852b2001-11-16 16:17:27 +0000642 (see below) says.
Jeremy Hylton249aaed2001-11-09 21:06:24 +0000643
Guido van Rossum12d955c2001-10-26 14:56:06 +0000644- Clarified the error messages for unsupported operands to an operator
645 (like 1 + '').
646
Tim Peters84362bc2001-10-19 17:55:30 +0000647Extension modules
648
Tim Peters5ebfd362001-11-13 23:11:19 +0000649- mmap has a new keyword argument, "access", allowing a uniform way for
650 both Windows and Unix users to create read-only, write-through and
651 copy-on-write memory mappings. This was previously possible only on
652 Unix. A new keyword argument was required to support this in a
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000653 uniform way because the mmap() signatures had diverged across
Tim Peters5ebfd362001-11-13 23:11:19 +0000654 platforms. Thanks to Jay T Miller for repairing this!
655
Tim Peters169ded02001-11-03 19:57:21 +0000656- By default, the gc.garbage list now contains only those instances in
657 unreachable cycles that have __del__ methods; in 2.1 it contained all
658 instances in unreachable cycles. "Instances" here has been generalized
659 to include instances of both new-style and old-style classes.
660
Guido van Rossum12d955c2001-10-26 14:56:06 +0000661- The socket module defines a new method for socket objects,
662 sendall(). This is like send() but may make multiple calls to
Guido van Rossum86443212001-10-27 22:28:54 +0000663 send() until all data has been sent. Also, the socket function has
664 been converted to a subclassable type, like list and tuple (etc.)
665 before it; socket and SocketType are now the same thing.
Guido van Rossum12d955c2001-10-26 14:56:06 +0000666
667- Various bugfixes to the curses module. There is now a test suite
668 for the curses module (you have to run it manually).
Andrew M. Kuchling15e03532001-10-22 16:37:10 +0000669
Guido van Rossum692adf12001-10-30 03:03:03 +0000670- binascii.b2a_base64 no longer places an arbitrary restriction of 57
671 bytes on its input.
672
Tim Peters84362bc2001-10-19 17:55:30 +0000673Library
674
Tim Peters5ebfd362001-11-13 23:11:19 +0000675- tkFileDialog exposes a Directory class and askdirectory
Martin v. Löwis25ee87c2001-11-07 22:38:08 +0000676 convenience function.
677
Tim Peters75335872001-11-03 19:35:43 +0000678- Symbolic group names in regular expressions must be unique. For
679 example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
680 single name can't mean both "group 1" and "group 2" simultaneously.
Barry Warsaw012852b2001-11-16 16:17:27 +0000681 Python 2.2 detects this error at regexp compilation time;
682 previously, the error went undetected, and results were
683 unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
684 pattern.subn() methods have been rewritten in C. Also, an
685 experimental function/method finditer() has been added, which works
686 like findall() but returns an iterator.
Tim Peters75335872001-11-03 19:35:43 +0000687
Martin v. Löwisb7b32602001-11-02 23:48:20 +0000688- Tix exposes more commands through the classes DirSelectBox,
689 DirSelectDialog, ListNoteBook, Meter, CheckList, and the
690 methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
691 tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
692
Tim Peters98791af2001-10-23 01:59:54 +0000693- Traceback objects are now scanned by cyclic garbage collection, so
694 cycles created by casual use of sys.exc_info() no longer cause
695 permanent memory leaks (provided garbage collection is enabled).
696
Guido van Rossum49192142001-10-24 20:51:44 +0000697- os.extsep -- a new variable needed by the RISCOS support. It is the
698 separator used by extensions, and is '.' on all platforms except
699 RISCOS, where it is '/'. There is no need to use this variable
700 unless you have a masochistic desire to port your code to RISCOS.
701
Barry Warsaw012852b2001-11-16 16:17:27 +0000702- mimetypes.py has optional support for non-standard, but commonly
703 found types. guess_type() and guess_extension() now accept an
704 optional `strict' flag, defaulting to true, which controls whether
705 recognize non-standard types or not. A few non-standard types we
706 know about have been added. Also, when run as a script, there are
707 new -l and -e options.
708
709- statcache is now deprecated.
710
711- email.Utils.formatdate() now produces the preferred RFC 2822 style
712 dates with numeric timezones (it used to produce obsolete dates
713 hard coded to "GMT" timezone). An optional `localtime' flag is
714 added to produce dates in the local timezone, with daylight savings
715 time properly taken into account.
716
717- In pickle and cPickle, instead of masking errors in load() by
718 transforming them into SystemError, we let the original exception
719 propagate out. Also, implement support for __safe_for_unpickling__
720 in pickle, as it already was supported in cPickle.
721
Tim Peters84362bc2001-10-19 17:55:30 +0000722Tools/Demos
723
724Build
725
Barry Warsaw012852b2001-11-16 16:17:27 +0000726- The dbm module is built using libdb1 if available. The bsddb module
727 is built with libdb3 if available.
728
729- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
730
Tim Peters84362bc2001-10-19 17:55:30 +0000731C API
732
Tim Peters1fc240e2001-10-26 05:06:50 +0000733- New function PySequence_Fast_GET_SIZE() returns the size of a non-
734 NULL result from PySequence_Fast(), more quickly than calling
735 PySequence_Size().
736
Barry Warsaw012852b2001-11-16 16:17:27 +0000737- New argument unpacking function PyArg_UnpackTuple() added.
738
739- New functions PyObject_CallFunctionObjArgs() and
740 PyObject_CallMethodObjArgs() have been added to make it more
741 convenient and efficient to call functions and methods from C.
742
743- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
744 possible that this will propagate errors it didn't before.
745
746- New function PyObject_CheckReadBuffer(), which returns true if its
747 argument supports the single-segment readable buffer interface.
748
Tim Peters84362bc2001-10-19 17:55:30 +0000749New platforms
750
Guido van Rossum86443212001-10-27 22:28:54 +0000751- We've finally confirmed that this release builds on HP-UX 11.00,
752 *with* threads, and passes the test suite.
753
Tim Peters7a33d8b2001-11-05 02:51:07 +0000754- Thanks to a series of patches from Michael Muller, Python may build
755 again under OS/2 Visual Age C++.
756
Guido van Rossum49192142001-10-24 20:51:44 +0000757- Updated RISCOS port by Dietmar Schwertberger.
758
Tim Peters84362bc2001-10-19 17:55:30 +0000759Tests
760
Andrew M. Kuchling15e03532001-10-22 16:37:10 +0000761- Added a test script for the curses module. It isn't run automatically;
762 regrtest.py must be run with '-u curses' to enable it.
763
Tim Peters84362bc2001-10-19 17:55:30 +0000764Windows
765
Barry Warsaw012852b2001-11-16 16:17:27 +0000766Mac
767
768- PythonScript has been moved to unsupported and is slated to be
769 removed completely in the next release.
770
771- It should now be possible to build applets that work on both OS9 and
772 OSX.
773
774- The core is now linked with CoreServices not Carbon; as a side
775 result, default 8bit encoding on OSX is now ASCII.
776
777- Python should now build on OSX 10.1.1
778
Tim Peters84362bc2001-10-19 17:55:30 +0000779
Tim Petersabf925f2001-09-28 21:53:42 +0000780What's New in Python 2.2b1?
Guido van Rossum1c486092001-10-19 02:05:35 +0000781Release date: 19-Oct-2001
Tim Petersabf925f2001-09-28 21:53:42 +0000782===========================
783
784Type/class unification and new-style classes
785
Guido van Rossum687ae002001-10-15 22:03:32 +0000786- New-style classes are now always dynamic (except for built-in and
Guido van Rossum3eea25c2001-10-16 00:46:57 +0000787 extension types). There is no longer a performance penalty, and I
Guido van Rossum687ae002001-10-15 22:03:32 +0000788 no longer see another reason to keep this baggage around. One relic
Guido van Rossum3eea25c2001-10-16 00:46:57 +0000789 remains: the __dict__ of a new-style class is a read-only proxy; you
790 must set the class's attribute to modify it. As a consequence, the
Guido van Rossum687ae002001-10-15 22:03:32 +0000791 __defined__ attribute of new-style types no longer exists, for lack
792 of need: there is once again only one __dict__ (although in the
Guido van Rossum3eea25c2001-10-16 00:46:57 +0000793 future a __cache__ may be resurrected with a similar function, if I
794 can prove that it actually speeds things up).
Guido van Rossum50fda3b2001-10-04 19:46:06 +0000795
Tim Peters1c9ca872001-10-04 06:43:12 +0000796- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
797 always returned None, even when there was a class docstring).
798
799- doctest now finds and runs docstrings attached to new-style classes,
800 class methods, static methods, and properties.
801
Guido van Rossum9074ef62001-10-16 21:34:49 +0000802Core and builtins
Tim Petersabf925f2001-09-28 21:53:42 +0000803
Guido van Rossuma8bcf802001-10-15 15:53:58 +0000804- A very subtle syntactical pitfall in list comprehensions was fixed.
805 For example: [a+b for a in 'abc', for b in 'def']. The comma in
806 this example is a mistake. Previously, this would silently let 'a'
807 iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
808 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
809 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
810 Note that [a for a in <singleton>] is a convoluted way to say
811 [<singleton>] anyway, so it's not like any expressiveness is lost.
812
Guido van Rossum9074ef62001-10-16 21:34:49 +0000813- getattr(obj, name, default) now only catches AttributeError, as
814 documented, rather than returning the default value for all
815 exceptions (which could mask bugs in a __getattr__ hook, for
816 example).
817
Fred Drakecb7a6b52001-10-22 18:41:51 +0000818- Weak reference objects are now part of the core and offer a C API.
Fred Drake934d2a42001-10-18 18:18:06 +0000819 A bug which could allow a core dump when binary operations involved
Andrew M. Kuchling51c18162001-10-22 01:47:26 +0000820 proxy reference has been fixed. weakref.ReferenceError is now a
Barry Warsawf6fb1712001-10-19 05:35:40 +0000821 built-in exception.
Fred Drake934d2a42001-10-18 18:18:06 +0000822
Guido van Rossum1c486092001-10-19 02:05:35 +0000823- unicode(obj) now behaves more like str(obj), accepting arbitrary
824 objects, and calling a __unicode__ method if it exists.
825 unicode(obj, encoding) and unicode(obj, encoding, errors) still
Marc-André Lemburgb5507ec2001-10-19 12:02:29 +0000826 require an 8-bit string or character buffer argument.
Guido van Rossum1c486092001-10-19 02:05:35 +0000827
Barry Warsawf6fb1712001-10-19 05:35:40 +0000828- isinstance() now allows any object as the first argument and a
829 class, a type or something with a __bases__ tuple attribute for the
830 second argument. The second argument may also be a tuple of a
831 class, type, or something with __bases__, in which case isinstance()
832 will return true if the first argument is an instance of any of the
833 things contained in the second argument tuple. E.g.
834
835 isinstance(x, (A, B))
836
837 returns true if x is an instance of A or B.
838
Guido van Rossum9074ef62001-10-16 21:34:49 +0000839Extension modules
840
841- thread.start_new_thread() now returns the thread ID (previously None).
842
Martin v. Löwis16dc7f42001-09-30 20:32:11 +0000843- binascii has now two quopri support functions, a2b_qp and b2a_qp.
844
Guido van Rossumc524d952001-10-19 01:31:59 +0000845- readline now supports setting the startup_hook and the
846 pre_event_hook, and adds the add_history() function.
Martin v. Löwis0daad592001-09-30 21:09:59 +0000847
Guido van Rossumc524d952001-10-19 01:31:59 +0000848- os and posix supports chroot(), setgroups() and unsetenv() where
849 available. The stat(), fstat(), statvfs() and fstatvfs() functions
850 now return "pseudo-sequences" -- the various fields can now be
851 accessed as attributes (e.g. os.stat("/").st_mtime) but for
852 backwards compatibility they also behave as a fixed-length sequence.
853 Some platform-specific fields (e.g. st_rdev) are only accessible as
Guido van Rossum98bf58f2001-10-18 20:34:25 +0000854 attributes.
855
856- time: localtime(), gmtime() and strptime() now return a
857 pseudo-sequence similar to the os.stat() return value, with
858 attributes like tm_year etc.
Martin v. Löwis16628c92001-10-04 22:46:41 +0000859
Guido van Rossum9074ef62001-10-16 21:34:49 +0000860- Decompression objects in the zlib module now accept an optional
861 second parameter to decompress() that specifies the maximum amount
862 of memory to use for the uncompressed data.
Tim Petersabf925f2001-09-28 21:53:42 +0000863
Jeremy Hyltoncb441432001-10-19 03:40:19 +0000864- optional SSL support in the socket module now exports OpenSSL
865 functions RAND_add(), RAND_egd(), and RAND_status(). These calls
866 are useful on platforms like Solaris where OpenSSL does not
Barry Warsawf6fb1712001-10-19 05:35:40 +0000867 automatically seed its PRNG. Also, the keyfile and certfile
868 arguments to socket.ssl() are now optional.
869
870- posixmodule (and by extension, the os module on POSIX platforms) now
871 exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
Jeremy Hyltoncb441432001-10-19 03:40:19 +0000872
Guido van Rossum9074ef62001-10-16 21:34:49 +0000873Library
Guido van Rossum3c288632001-10-16 21:13:49 +0000874
Tim Peters7402f792001-10-02 03:53:41 +0000875- doctest now excludes functions and classes not defined by the module
876 being tested, thanks to Tim Hochberg.
877
Fred Drakecb7a6b52001-10-22 18:41:51 +0000878- HotShot, a new profiler implemented using a C-based callback, has
879 been added. This substantially reduces the overhead of profiling,
880 but it is still quite preliminary. Support modules and
881 documentation will be added in upcoming releases (before 2.2 final).
882
Guido van Rossumc4b09b42001-10-04 10:19:00 +0000883- profile now produces correct output in situations where an exception
884 raised in Python is cleared by C code (e.g. hasattr()). This used
885 to cause wrong output, including spurious claims of recursive
886 functions and attribution of time spent to the wrong function.
887
Tim Peters0a1fc4e2001-10-07 03:12:08 +0000888 The code and documentation for the derived OldProfile and HotProfile
889 profiling classes was removed. The code hasn't worked for years (if
890 you tried to use them, they raised exceptions). OldProfile
891 intended to reproduce the behavior of the profiler Python used more
892 than 7 years ago, and isn't interesting anymore. HotProfile intended
893 to provide a faster profiler (but producing less information), and
894 that's a worthy goal we intend to meet via a different approach (but
895 without losing information).
896
Tim Peterscce092d2001-10-09 05:31:56 +0000897- Profile.calibrate() has a new implementation that should deliver
Tim Peters659a6032001-10-09 20:51:19 +0000898 a much better system-specific calibration constant. The constant can
899 now be specified in an instance constructor, or as a Profile class or
900 instance variable, instead of by editing profile.py's source code.
901 Calibration must still be done manually (see the docs for the profile
902 module).
903
904 Note that Profile.calibrate() must be overriden by subclasses.
905 Improving the accuracy required exploiting detailed knowledge of
906 profiler internals; the earlier method abstracted away the details
907 and measured a simplified model instead, but consequently computed
908 a constant too small by a factor of 2 on some modern machines.
Tim Peterscce092d2001-10-09 05:31:56 +0000909
Martin v. Löwis16dc7f42001-09-30 20:32:11 +0000910- quopri's encode and decode methods take an optional header parameter,
Jeremy Hylton6f543b62001-10-16 20:42:52 +0000911 which indicates whether output is intended for the header 'Q'
912 encoding.
913
Guido van Rossuma5343cc2001-10-18 18:02:07 +0000914- The SocketServer.ThreadingMixIn class now closes the request after
915 finish_request() returns. (Not when it errors out though.)
916
Barry Warsawf6fb1712001-10-19 05:35:40 +0000917- The nntplib module's NNTP.body() method has grown a `file' argument
918 to allow saving the message body to a file.
919
920- The email package has added a class email.Parser.HeaderParser which
921 only parses headers and does not recurse into the message's body.
922 Also, the module/class MIMEAudio has been added for representing
923 audio data (contributed by Anthony Baxter).
924
925- ftplib should be able to handle files > 2GB.
926
927- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
928 ON, and OFF.
929
Fred Drakecb7a6b52001-10-22 18:41:51 +0000930- xml.dom.minidom NodeList objects now support the length attribute
931 and item() method as required by the DOM specifications.
932
Guido van Rossumed554f62001-10-02 23:15:37 +0000933Tools/Demos
934
935- Demo/dns was removed. It no longer serves any purpose; a package
936 derived from it is now maintained by Anthony Baxter, see
937 http://PyDNS.SourceForge.net.
Tim Petersabf925f2001-09-28 21:53:42 +0000938
Barry Warsawf6fb1712001-10-19 05:35:40 +0000939- The freeze tool has been made more robust, and two new options have
940 been added: -X and -E.
941
Tim Petersabf925f2001-09-28 21:53:42 +0000942Build
943
Barry Warsawf6fb1712001-10-19 05:35:40 +0000944- configure will use CXX in LINKCC if CXX is used to build main() and
945 the system requires to link a C++ main using the C++ compiler.
946
Tim Petersabf925f2001-09-28 21:53:42 +0000947C API
948
Guido van Rossum6c4bce32001-10-18 19:20:25 +0000949- The documentation for the tp_compare slot is updated to require that
950 the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
951 not correct. This is not yet enforced but will be enforced in
952 Python 2.3; even later, we may use -2 to indicate errors and +2 for
953 "NotImplemented". Right now, -1 should be used for an error return.
954
Tim Petersd38b1c72001-09-30 05:09:37 +0000955- PyLong_AsLongLong() now accepts int (as well as long) arguments.
956 Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
957 as long) arguments.
958
Guido van Rossum3c288632001-10-16 21:13:49 +0000959- PyThread_start_new_thread() now returns a long int giving the thread
960 ID, if one can be calculated; it returns -1 for error, 0 if no
961 thread ID is calculated (this is an incompatible change, but only
962 the thread module used this API). This code has only really been
963 tested on Linux and Windows; other platforms please beware (and
964 report any bugs or strange behavior).
965
Guido van Rossum1c486092001-10-19 02:05:35 +0000966- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
967 input.
968
Tim Petersabf925f2001-09-28 21:53:42 +0000969New platforms
970
971Tests
972
973Windows
974
Tim Peters04cf1d32001-10-09 22:39:40 +0000975- Installer: If you install IDLE, and don't disable file-extension
976 registration, a new "Edit with IDLE" context (right-click) menu entry
977 is created for .py and .pyw files.
978
Tim Peters1ce3cf72001-10-01 17:58:40 +0000979- The signal module now supports SIGBREAK on Windows, thanks to Steven
980 Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
981 action remains to call Win32 ExitProcess(). This can be changed via
982 signal.signal(). For example:
983
984 # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
985 # (SIGINT) behavior.
986 import signal
987 signal.signal(signal.SIGBREAK,
988 signal.default_int_handler)
989
990 try:
991 while 1:
992 pass
993 except KeyboardInterrupt:
994 # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
995 # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
996 # program without the possibility for any Python-level cleanup).
997 print "Clean exit"
998
Tim Petersabf925f2001-09-28 21:53:42 +0000999
Tim Petersb07352e2001-09-08 01:25:47 +00001000What's New in Python 2.2a4?
Barry Warsaw86fbaf82001-09-28 15:26:12 +00001001Release date: 28-Sep-2001
Tim Petersb07352e2001-09-08 01:25:47 +00001002===========================
1003
Guido van Rossum808eea72001-09-25 04:15:41 +00001004Type/class unification and new-style classes
1005
1006- pydoc and inspect are now aware of new-style classes;
1007 e.g. help(list) at the interactive prompt now shows proper
1008 documentation for all operations on list objects.
1009
1010- Applications using Jim Fulton's ExtensionClass module can now safely
1011 be used with Python 2.2. In particular, Zope 2.4.1 now works with
1012 Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
1013 examples also work again. It is hoped that Gtk and Boost also work
1014 with 2.2a4 and beyond. (If you can confirm this, please write
1015 webmaster@python.org; if there are still problems, please open a bug
1016 report on SourceForge.)
Tim Petersb07352e2001-09-08 01:25:47 +00001017
Tim Peters66c1a522001-09-24 21:17:50 +00001018- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001019 These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
Tim Peters66c1a522001-09-24 21:17:50 +00001020 in the constructed property object. fget, fset and fdel weren't
1021 discoverable from Python in 2.2a3. __doc__ is new, and allows to
1022 associate a docstring with a property.
1023
Guido van Rossum808eea72001-09-25 04:15:41 +00001024- Comparison overloading is now more completely implemented. For
1025 example, a str subclass instance can properly be compared to a str
1026 instance, and it can properly overload comparison. Ditto for most
1027 other built-in object types.
1028
1029- The repr() of new-style classes has changed; instead of <type
1030 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
1031 *except* for built-in types, which are still rendered as <type
1032 'Foo'> (to avoid upsetting existing code that might parse or
1033 otherwise rely on repr() of certain type objects).
1034
1035- The repr() of new-style objects is now always <Foo object at XXX>;
1036 previously, it was sometimes <Foo instance at XXX>.
1037
1038- For new-style classes, what was previously called __getattr__ is now
1039 called __getattribute__. This method, if defined, is called for
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001040 *every* attribute access. A new __getattr__ hook more similar to the
Guido van Rossum808eea72001-09-25 04:15:41 +00001041 one in classic classes is defined which is called only if regular
1042 attribute access raises AttributeError; to catch *all* attribute
1043 access, you can use __getattribute__ (for new-style classes). If
1044 both are defined, __getattribute__ is called first, and if it raises
1045 AttributeError, __getattr__ is called.
1046
1047- The __class__ attribute of new-style objects can be assigned to.
1048 The new class must have the same C-level object layout as the old
1049 class.
1050
1051- The builtin file type can be subclassed now. In the usual pattern,
1052 "file" is the name of the builtin type, and file() is a new builtin
1053 constructor, with the same signature as the builtin open() function.
1054 file() is now the preferred way to open a file.
1055
1056- Previously, __new__ would only see sequential arguments passed to
1057 the type in a constructor call; __init__ would see both sequential
1058 and keyword arguments. This made no sense whatsoever any more, so
1059 now both __new__ and __init__ see all arguments.
1060
1061- Previously, hash() applied to an instance of a subclass of str or
1062 unicode always returned 0. This has been repaired.
1063
1064- Previously, an operation on an instance of a subclass of an
1065 immutable type (int, long, float, complex, tuple, str, unicode),
1066 where the subtype didn't override the operation (and so the
1067 operation was handled by the builtin type), could return that
1068 instance instead a value of the base type. For example, if s was of
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001069 a str subclass type, s[:] returned s as-is. Now it returns a str
Guido van Rossum808eea72001-09-25 04:15:41 +00001070 with the same value as s.
1071
Barry Warsaw86fbaf82001-09-28 15:26:12 +00001072- Provisional support for pickling new-style objects has been added.
1073
Guido van Rossum808eea72001-09-25 04:15:41 +00001074Core
1075
Tim Peters2c9aa5e2001-09-23 04:06:05 +00001076- file.writelines() now accepts any iterable object producing strings.
1077
Marc-André Lemburgaefd7662001-09-20 12:59:37 +00001078- PyUnicode_FromEncodedObject() now works very much like
1079 PyObject_Str(obj) in that it tries to use __str__/tp_str
1080 on the object if the object is not a string or buffer. This
1081 makes unicode() behave like str() when applied to non-string/buffer
1082 objects.
1083
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001084- PyFile_WriteObject now passes Unicode objects to the file's write
1085 method. As a result, all file-like objects which may be the target
Martin v. Löwis2777c022001-09-19 13:47:32 +00001086 of a print statement must support Unicode objects, i.e. they must
1087 at least convert them into ASCII strings.
1088
Guido van Rossum624c8af2001-09-18 15:21:04 +00001089- Thread scheduling on Solaris should be improved; it is no longer
1090 necessary to insert a small sleep at the start of a thread in order
1091 to let other runnable threads be scheduled.
1092
Tim Petersb07352e2001-09-08 01:25:47 +00001093Library
1094
Marc-André Lemburgbf990172001-09-27 14:17:33 +00001095- StringIO.StringIO instances and cStringIO.StringIO instances support
1096 read character buffer compatible objects for their .write() methods.
1097 These objects are converted to strings and then handled as such
1098 by the instances.
1099
Barry Warsaw2f600732001-09-24 04:28:10 +00001100- The "email" package has been added. This is basically a port of the
1101 mimelib package <http://sf.net/projects/mimelib> with API changes
1102 and some implementations updated to use iterators and generators.
1103
Tim Peters8a9c2842001-09-22 21:30:22 +00001104- difflib.ndiff() and difflib.Differ.compare() are generators now. This
1105 restores the ability of Tools/scripts/ndiff.py to start producing output
1106 before the entire comparison is complete.
1107
Barry Warsaw58b072d2001-09-22 04:44:21 +00001108- StringIO.StringIO instances and cStringIO.StringIO instances support
1109 iteration just like file objects (i.e. their .readline() method is
1110 called for each iteration until it returns an empty string).
1111
Marc-André Lemburg494f2ae2001-09-19 11:33:31 +00001112- The codecs module has grown four new helper APIs to access
1113 builtin codecs: getencoder(), getdecoder(), getreader(),
1114 getwriter().
1115
Guido van Rossum624c8af2001-09-18 15:21:04 +00001116- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
1117 simplifies writing XML RPC servers.
1118
Barry Warsaw647d5e82001-09-28 17:01:02 +00001119- os.path.realpath(): a new function that returns the absolute pathname
Guido van Rossum624c8af2001-09-18 15:21:04 +00001120 after interpretation of symbolic links. On non-Unix systems, this
1121 is an alias for os.path.abspath().
1122
Tim Peters16a77ad2001-09-08 04:00:12 +00001123- operator.indexOf() (PySequence_Index() in the C API) now works with any
1124 iterable object.
1125
Guido van Rossum624c8af2001-09-18 15:21:04 +00001126- smtplib now supports various authentication and security features of
1127 the SMTP protocol through the new login() and starttls() methods.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00001128
Guido van Rossum624c8af2001-09-18 15:21:04 +00001129- hmac: a new module implementing keyed hashing for message
1130 authentication.
1131
1132- mimetypes now recognizes more extensions and file types. At the
1133 same time, some mappings not sanctioned by IANA were removed.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00001134
Guido van Rossum624c8af2001-09-18 15:21:04 +00001135- The "compiler" package has been brought up to date to the state of
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00001136 Python 2.2 bytecode generation. It has also been promoted from a
1137 Tool to a standard library package. (Tools/compiler still exists as
1138 a sample driver.)
1139
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00001140Tools
Guido van Rossum624c8af2001-09-18 15:21:04 +00001141
Tim Petersb07352e2001-09-08 01:25:47 +00001142Build
1143
Guido van Rossum624c8af2001-09-18 15:21:04 +00001144- Large file support (LFS) is now automatic when the platform supports
1145 it; no more manual configuration tweaks are needed. On Linux, at
1146 least, it's possible to have a system whose C library supports large
1147 files but whose kernel doesn't; in this case, large file support is
1148 still enabled but doesn't do you any good unless you upgrade your
1149 kernel or share your Python executable with another system whose
1150 kernel has large file support.
1151
1152- The configure script now supplies plausible defaults in a
1153 cross-compilation environment. This doesn't mean that the supplied
1154 values are always correct, or that cross-compilation now works
1155 flawlessly -- but it's a first step (and it shuts up most of
1156 autoconf's warnings about AC_TRY_RUN).
1157
1158- The Unix build is now a bit less chatty, courtesy of the parser
1159 generator. The build is completely silent (except for errors) when
1160 using "make -s", thanks to a -q option to setup.py.
1161
Tim Petersb07352e2001-09-08 01:25:47 +00001162C API
1163
Guido van Rossum624c8af2001-09-18 15:21:04 +00001164- The "structmember" API now supports some new flag bits to deny read
1165 and/or write access to attributes in restricted execution mode.
1166
Tim Petersb07352e2001-09-08 01:25:47 +00001167New platforms
1168
Guido van Rossum624c8af2001-09-18 15:21:04 +00001169- Compaq's iPAQ handheld, running the "familiar" Linux distribution
1170 (http://familiar.handhelds.org).
1171
Tim Petersb07352e2001-09-08 01:25:47 +00001172Tests
1173
Tim Peters8a9c2842001-09-22 21:30:22 +00001174- The "classic" standard tests, which work by comparing stdout to
1175 an expected-output file under Lib/test/output/, no longer stop at
1176 the first mismatch. Instead the test is run to completion, and a
1177 variant of ndiff-style comparison is used to report all differences.
1178 This is much easier to understand than the previous style of reporting.
1179
1180- The unittest-based standard tests now use regrtest's test_main()
1181 convention, instead of running as a side-effect of merely being
1182 imported. This allows these tests to be run in more natural and
1183 flexible ways as unittests, outside the regrtest framework.
1184
1185- regrtest.py is much better integrated with unittest and doctest now,
1186 especially in regard to reporting errors.
1187
Tim Petersb07352e2001-09-08 01:25:47 +00001188Windows
1189
Guido van Rossum624c8af2001-09-18 15:21:04 +00001190- Large file support now also works for files > 4GB, on filesystems
Tim Peters8a9c2842001-09-22 21:30:22 +00001191 that support it (NTFS under Windows 2000). See "What's New in
1192 Python 2.2a3" for more detail.
Guido van Rossum624c8af2001-09-18 15:21:04 +00001193
Tim Petersb07352e2001-09-08 01:25:47 +00001194
Tim Petersedc99312001-08-22 21:36:50 +00001195What's New in Python 2.2a3?
Barry Warsaw86fbaf82001-09-28 15:26:12 +00001196Release Date: 07-Sep-2001
Tim Petersedc99312001-08-22 21:36:50 +00001197===========================
1198
1199Core
1200
Tim Peters9fffa3e2001-09-04 05:14:19 +00001201- Conversion of long to float now raises OverflowError if the long is too
1202 big to represent as a C double.
1203
Tim Peters32f453e2001-09-03 08:35:41 +00001204- The 3-argument builtin pow() no longer allows a third non-None argument
1205 if either of the first two arguments is a float, or if both are of
1206 integer types and the second argument is negative (in which latter case
1207 the arguments are converted to float, so this is really the same
1208 restriction).
1209
Tim Peters5d2b77c2001-09-03 05:47:38 +00001210- The builtin dir() now returns more information, and sometimes much
1211 more, generally naming all attributes of an object, and all attributes
1212 reachable from the object via its class, and from its class's base
1213 classes, and so on from them too. Example: in 2.2a2, dir([]) returned
1214 an empty list. In 2.2a3,
1215
1216 >>> dir([])
1217 ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
1218 '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
1219 '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
1220 '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
1221 '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
1222 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
1223 'reverse', 'sort']
1224
1225 dir(module) continues to return only the module's attributes, though.
1226
Tim Petersbdee63f2001-09-02 03:40:59 +00001227- Overflowing operations on plain ints now return a long int rather
Guido van Rossumae457142001-08-31 18:31:35 +00001228 than raising OverflowError. This is a partial implementation of PEP
1229 237. You can use -Wdefault::OverflowWarning to enable a warning for
1230 this situation, and -Werror::OverflowWarning to revert to the old
1231 OverflowError exception.
1232
Guido van Rossum61c345f2001-09-04 03:26:15 +00001233- A new command line option, -Q<arg>, is added to control run-time
Guido van Rossumae457142001-08-31 18:31:35 +00001234 warnings for the use of classic division. (See PEP 238.) Possible
Barry Warsawd6c8ca62001-09-07 18:13:44 +00001235 values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
1236 -Qold, meaning the / operator has its classic meaning and no
1237 warnings are issued. Using -Qwarn issues a run-time warning about
1238 all uses of classic division for int and long arguments; -Qwarnall
1239 also warns about classic division for float and complex arguments
Tim Peters3caca232001-12-06 06:23:26 +00001240 (for use with fixdiv.py).
1241 [Note: the remainder of this paragraph (preserved below) became
1242 obsolete in 2.2c1 -- -Qnew has global effect in 2.2]
1243 <obsolete>
1244 Using -Qnew is questionable; it turns on new division by default, but
1245 only in the __main__ module. You can usefully combine -Qwarn or
1246 -Qwarnall and -Qnew: this gives the __main__ module new division, and
1247 warns about classic division everywhere else.
1248 </obsolete>
Guido van Rossumae457142001-08-31 18:31:35 +00001249
Tim Petersbdee63f2001-09-02 03:40:59 +00001250- Many built-in types can now be subclassed. This applies to int,
Guido van Rossumae457142001-08-31 18:31:35 +00001251 long, float, str, unicode, and tuple. (The types complex, list and
1252 dictionary can also be subclassed; this was introduced earlier.)
1253 Note that restrictions apply when subclassing immutable built-in
1254 types: you can only affect the value of the instance by overloading
1255 __new__. You can add mutable attributes, and the subclass instances
1256 will have a __dict__ attribute, but you cannot change the "value"
1257 (as implemented by the base class) of an immutable subclass instance
1258 once it is created.
1259
Guido van Rossumaaf80c82001-09-02 13:44:35 +00001260- The dictionary constructor now takes an optional argument, a
1261 mapping-like object, and initializes the dictionary from its
1262 (key, value) pairs.
1263
Tim Petersbdee63f2001-09-02 03:40:59 +00001264- A new built-in type, super, has been added. This facilitates making
Guido van Rossumae457142001-08-31 18:31:35 +00001265 "cooperative super calls" in a multiple inheritance setting. For an
1266 explanation, see http://www.python.org/2.2/descrintro.html#cooperation
1267
Guido van Rossum8d7234d2001-09-06 22:02:58 +00001268- A new built-in type, property, has been added. This enables the
1269 creation of "properties". These are attributes implemented by
1270 getter and setter functions (or only one of these for read-only or
1271 write-only attributes), without the need to override __getattr__.
1272 See http://www.python.org/2.2/descrintro.html#property
Guido van Rossumae457142001-08-31 18:31:35 +00001273
Tim Petersbdee63f2001-09-02 03:40:59 +00001274- The syntax of floating-point and imaginary literals has been
Tim Petersd507dab2001-08-30 20:51:59 +00001275 liberalized, to allow leading zeroes. Examples of literals now
1276 legal that were SyntaxErrors before:
1277
1278 00.0 0e3 0100j 07.5 00000000000000000008.
1279
Tim Petersbdee63f2001-09-02 03:40:59 +00001280- An old tokenizer bug allowed floating point literals with an incomplete
Tim Petersc6d95812001-08-28 20:56:27 +00001281 exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
1282
Tim Petersedc99312001-08-22 21:36:50 +00001283Library
1284
Martin v. Löwiscb227c92001-09-06 08:54:16 +00001285- telnetlib includes symbolic names for the options, and support for
1286 setting an option negotiation callback.
1287
Tim Petersa40c7932001-09-05 22:36:56 +00001288- The new C standard no longer requires that math libraries set errno to
1289 ERANGE on overflow. For platform libraries that exploit this new
1290 freedom, Python's overflow-checking was wholly broken. A new overflow-
1291 checking scheme attempts to repair that, but may not be reliable on all
1292 platforms (C doesn't seem to provide anything both useful and portable
1293 in this area anymore).
1294
Martin v. Löwis44f86962001-09-05 13:44:54 +00001295- Asynchronous timeout actions are available through the new class
1296 threading.Timer.
1297
Tim Peters78526162001-09-05 00:53:45 +00001298- math.log and math.log10 now return sensible results for even huge
1299 long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
1300
Tim Petersbdee63f2001-09-02 03:40:59 +00001301- A new function, imp.lock_held(), returns 1 when the import lock is
Tim Peters69232342001-08-30 05:16:13 +00001302 currently held. See the docs for the imp module.
1303
Tim Petersbdee63f2001-09-02 03:40:59 +00001304- pickle, cPickle and marshal on 32-bit platforms can now correctly read
Tim Peters82112372001-08-29 02:28:42 +00001305 dumps containing ints written on platforms where Python ints are 8 bytes.
1306 When read on a box where Python ints are 4 bytes, such values are
1307 converted to Python longs.
1308
Tim Petersbdee63f2001-09-02 03:40:59 +00001309- In restricted execution mode (using the rexec module), unmarshalling
Guido van Rossumae457142001-08-31 18:31:35 +00001310 code objects is no longer allowed. This plugs a security hole.
1311
Steve Purcell6091cd62001-09-06 16:05:17 +00001312- unittest.TestResult instances no longer store references to tracebacks
1313 generated by test failures. This prevents unexpected dangling references
1314 to objects that should be garbage collected between tests.
1315
Tim Petersedc99312001-08-22 21:36:50 +00001316Tools
1317
Barry Warsawd6c8ca62001-09-07 18:13:44 +00001318- Tools/scripts/fixdiv.py has been added which can be used to fix
1319 division operators as per PEP 238.
1320
Tim Petersedc99312001-08-22 21:36:50 +00001321Build
1322
Barry Warsawd6c8ca62001-09-07 18:13:44 +00001323- If you are an adventurous person using Mac OS X you may want to look at
1324 Mac/OSX. There is a Makefile there that will build Python as a real Mac
1325 application, which can be used for experimenting with Carbon or Cocoa.
1326 Discussion of this on pythonmac-sig, please.
1327
Tim Peters7eea37e2001-09-04 22:08:56 +00001328C API
1329
1330- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
Tim Peters69232342001-08-30 05:16:13 +00001331
Tim Peters9fffa3e2001-09-04 05:14:19 +00001332- Note that PyLong_AsDouble can fail! This has always been true, but no
1333 callers checked for it. It's more likely to fail now, because overflow
1334 errors are properly detected now. The proper way to check:
1335
1336 double x = PyLong_AsDouble(some_long_object);
1337 if (x == -1.0 && PyErr_Occurred()) {
1338 /* The conversion failed. */
1339 }
1340
Tim Petersbdee63f2001-09-02 03:40:59 +00001341- The GC API has been changed. Extensions that use the old API will still
Neil Schemenauer4042c692001-08-30 15:38:01 +00001342 compile but will not participate in GC. To upgrade an extension
1343 module:
1344
1345 - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
Tim Petersd507dab2001-08-30 20:51:59 +00001346
Neil Schemenauer4042c692001-08-30 15:38:01 +00001347 - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
1348 PyObject_GC_Del to deallocate them
Tim Petersd507dab2001-08-30 20:51:59 +00001349
Neil Schemenauer4042c692001-08-30 15:38:01 +00001350 - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
1351 to PyObject_GC_UnTrack
Tim Petersd507dab2001-08-30 20:51:59 +00001352
Neil Schemenauer4042c692001-08-30 15:38:01 +00001353 - remove PyGC_HEAD_SIZE from object size calculations
1354
1355 - remove calls to PyObject_AS_GC and PyObject_FROM_GC
1356
Tim Petersbdee63f2001-09-02 03:40:59 +00001357- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
Guido van Rossumae457142001-08-31 18:31:35 +00001358 These can be used safely to construct string objects from a
1359 sprintf-style format string (similar to the format string supported
1360 by PyErr_Format()).
Tim Peters69232342001-08-30 05:16:13 +00001361
Tim Petersedc99312001-08-22 21:36:50 +00001362New platforms
1363
Tim Petersb7da0902001-09-02 23:01:43 +00001364- Stephen Hansen contributed patches sufficient to get a clean compile
1365 under Borland C (Windows), but he reports problems running it and ran
1366 out of time to complete the port. Volunteers? Expect a MemoryError
1367 when importing the types module; this is probably shallow, and
1368 causing later failures too.
Tim Petersbdee63f2001-09-02 03:40:59 +00001369
Tim Petersedc99312001-08-22 21:36:50 +00001370Tests
1371
1372Windows
1373
Tim Peters6e13a562001-09-06 00:32:15 +00001374- Large file support is now enabled on Win32 platforms as well as on
1375 Win64. This means that, for example, you can use f.tell() and f.seek()
1376 to manipulate files larger than 2 gigabytes (provided you have enough
1377 disk space, and are using a Windows filesystem that supports large
Tim Peters9a9471c2001-09-11 23:18:51 +00001378 partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
1379 filesize limit, and large file support makes no difference there.
1380 FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
1381 NTFS has no practical limit on file size, and files of any size can be
1382 used from Python now.
Tim Peters6e13a562001-09-06 00:32:15 +00001383
Tim Petersbdee63f2001-09-02 03:40:59 +00001384- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
Tim Peters402d5982001-08-27 06:37:48 +00001385 points to command.com (patch from Brian Quinlan).
1386
Tim Petersedc99312001-08-22 21:36:50 +00001387
Tim Peters20f51a72001-07-21 02:31:40 +00001388What's New in Python 2.2a2?
Barry Warsaw86fbaf82001-09-28 15:26:12 +00001389Release Date: 22-Aug-2001
Tim Peters20f51a72001-07-21 02:31:40 +00001390===========================
1391
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001392Build
1393
Barry Warsaw18b2ecf2001-08-22 20:26:56 +00001394- Tim Peters developed a brand new Windows installer using Wise 8.1,
1395 generously donated to us by Wise Solutions.
1396
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001397- configure supports a new option --enable-unicode, with the values
1398 ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
1399 type and supporting code is completely removed from the interpreter.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001400
Jack Jansen32ce0cd2001-08-21 19:28:20 +00001401- A new configure option --enable-framework builds a Mac OS X framework,
1402 which "make frameworkinstall" will install. This provides a starting
1403 point for more mac-like functionality, join pythonmac-sig@python.org
1404 if you are interested in helping.
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001405
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001406- The NeXT platform is no longer supported.
1407
1408- The `new' module is now statically linked.
1409
Tim Peters0afb6092001-08-15 06:06:44 +00001410Tools
1411
1412- The new Tools/scripts/cleanfuture.py can be used to automatically
Andrew M. Kuchlingb0532092001-08-15 15:54:56 +00001413 edit out obsolete future statements from Python source code. See
Tim Peters0afb6092001-08-15 06:06:44 +00001414 the module docstring for details.
1415
Tim Peters20f51a72001-07-21 02:31:40 +00001416Tests
1417
Tim Peters5e824c32001-08-12 22:25:01 +00001418- regrtest.py now knows which tests are expected to be skipped on some
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001419 platforms, allowing to give clearer test result output. regrtest
1420 also has optional --use/-u switch to run normally disabled tests
1421 which require network access or consume significant disk resources.
Tim Peters5e824c32001-08-12 22:25:01 +00001422
Tim Peters20f51a72001-07-21 02:31:40 +00001423- Several new tests in the standard test suite, with special thanks to
1424 Nick Mathewson.
1425
1426Core
1427
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001428- The floor division operator // has been added as outlined in PEP
1429 238. The / operator still provides classic division (and will until
1430 Python 3.0) unless "from __future__ import division" is included, in
1431 which case the / operator will provide true division. The operator
1432 module provides truediv() and floordiv() functions. Augmented
1433 assignment variants are included, as are the equivalent overloadable
1434 methods and C API methods. See the PEP for a full discussion:
1435 <http://python.sf.net/peps/pep-0238.html>
1436
Tim Peters6cd6a822001-08-17 22:11:27 +00001437- Future statements are now effective in simulated interactive shells
1438 (like IDLE). This should "just work" by magic, but read Michael
1439 Hudson's "Future statements in simulated shells" PEP 264 for full
1440 details: <http://python.sf.net/peps/pep-0264.html>.
1441
Guido van Rossumf86ddd22001-08-17 21:21:04 +00001442- The type/class unification (PEP 252-253) was integrated into the
1443 trunk and is not so tentative any more (the exact specification of
1444 some features is still tentative). A lot of work has done on fixing
1445 bugs and adding robustness and features (performance still has to
1446 come a long way).
1447
Marc-André Lemburg888fac02001-07-31 14:24:31 +00001448- Warnings about a mismatch in the Python API during extension import
1449 now use the Python warning framework (which makes it possible to
1450 write filters for these warnings).
1451
Barry Warsaw9b3be7f2001-08-14 18:35:02 +00001452- A function's __dict__ (aka func_dict) will now always be a
1453 dictionary. It used to be possible to delete it or set it to None,
1454 but now both actions raise TypeErrors. It is still legal to set it
1455 to a dictionary object. Getting func.__dict__ before any attributes
1456 have been assigned now returns an empty dictionary instead of None.
1457
Guido van Rossum32aa5d22001-09-05 18:43:35 +00001458- A new command line option, -E, was added which disables the use of
1459 all environment variables, or at least those that are specifically
1460 significant to Python. Usually those have a name starting with
1461 "PYTHON". This was used to fix a problem where the tests fail if
1462 the user happens to have PYTHONHOME or PYTHONPATH pointing to an
1463 older distribution.
1464
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001465Library
1466
Tim Peters5e824c32001-08-12 22:25:01 +00001467- New class Differ and new functions ndiff() and restore() in difflib.py.
1468 These package the algorithms used by the popular Tools/scripts/ndiff.py,
Tim Peters0afb6092001-08-15 06:06:44 +00001469 for programmatic reuse.
Tim Peters5e824c32001-08-12 22:25:01 +00001470
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001471- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
1472 value using the minimal quoting required for the value; more
1473 reliable than using xml.sax.saxutils.escape() for attribute values.
1474
1475- Readline completion support for cmd.Cmd was added.
1476
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001477- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
1478
1479- Added function threading.BoundedSemaphore()
1480
1481- Added Ka-Ping Yee's cgitb.py module.
1482
1483- The `new' module now exposes the CO_xxx flags.
1484
Martin v. Löwis560da622001-11-24 09:24:51 +00001485- The gc module offers the get_referents function.
1486
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001487New platforms
1488
1489C API
1490
Marc-André Lemburg888fac02001-07-31 14:24:31 +00001491- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
1492 which provide a cross-platform implementations for the
1493 relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
1494 the standard sprintf() and vsprintf() C lib APIs, these versions
1495 apply bounds checking on the used buffer which enhances protection
1496 against buffer overruns.
1497
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00001498- Unicode APIs now use name mangling to assure that mixing interpreters
Tim Petersc1731372001-08-04 08:12:36 +00001499 and extensions using different Unicode widths is rendered next to
1500 impossible. Trying to import an incompatible Unicode-aware extension
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00001501 will result in an ImportError. Unicode extensions writers must make
1502 sure to check the Unicode width compatibility in their extensions by
1503 using at least one of the mangled Unicode APIs in the extension.
1504
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001505- Two new flags METH_NOARGS and METH_O are available in method definition
1506 tables to simplify implementation of methods with no arguments and a
1507 single untyped argument. Calling such methods is more efficient than
1508 calling corresponding METH_VARARGS methods. METH_OLDARGS is now
1509 deprecated.
1510
Tim Petersc1731372001-08-04 08:12:36 +00001511Windows
1512
1513- "import module" now compiles module.pyw if it exists and nothing else
1514 relevant is found.
1515
Tim Peters20f51a72001-07-21 02:31:40 +00001516
Guido van Rossum55a78992001-07-17 17:22:32 +00001517What's New in Python 2.2a1?
Barry Warsawd970fe42001-10-25 21:53:30 +00001518Release date: 18-Jul-2001
Tim Petersf553f892001-05-01 20:45:31 +00001519===========================
1520
1521Core
Tim Petersa814db52001-05-14 07:05:58 +00001522
Tim Peters6d6c1a32001-08-02 04:15:00 +00001523- TENTATIVELY, a large amount of code implementing much of what's
1524 described in PEP 252 (Making Types Look More Like Classes) and PEP
1525 253 (Subtyping Built-in Types) was added. This will be released
1526 with Python 2.2a1. Documentation will be provided separately
1527 through http://www.python.org/2.2/. The purpose of releasing this
1528 with Python 2.2a1 is to test backwards compatibility. It is
1529 possible, though not likely, that a decision is made not to release
1530 this code as part of 2.2 final, if any serious backwards
1531 incompapatibilities are found during alpha testing that cannot be
1532 repaired.
1533
Guido van Rossum55a78992001-07-17 17:22:32 +00001534- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +00001535 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +00001536 more 'yield' statements. See PEP 255. Since this adds a new
1537 keyword to the language, this feature must be enabled by including a
1538 future statement: "from __future__ import generators" (see PEP 236).
1539 Generators will become a standard feature in a future release
1540 (probably 2.3). Without this future statement, 'yield' remains an
1541 ordinary identifier, but a warning is issued each time it is used.
1542 (These warnings currently don't conform to the warnings framework of
1543 PEP 230; we intend to fix this in 2.2a2.)
1544
Marc-André Lemburg12e74b32001-05-22 08:58:23 +00001545- The UTF-16 codec was modified to be more RFC compliant. It will now
1546 only remove BOM characters at the start of the string and then
1547 only if running in native mode (UTF-16-LE and -BE won't remove a
1548 leading BMO character).
1549
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00001550- Strings now have a new method .decode() to complement the already
1551 existing .encode() method. These two methods provide direct access
1552 to the corresponding decoders and encoders of the registered codecs.
1553
1554 To enhance the usability of the .encode() method, the special
1555 casing of Unicode object return values was dropped (Unicode objects
1556 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +00001557
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00001558 Both methods will now return whatever the codec in charge of the
1559 requested encoding returns as object, e.g. Unicode codecs will
1560 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
1561 will return u"äöü"). This enables codec writer to create codecs
1562 for various simple to use conversions.
1563
1564 New codecs were added to demonstrate these new features (the .encode()
1565 and .decode() columns indicate the type of the returned objects):
1566
1567 Name | .encode() | .decode() | Description
1568 ----------------------------------------------------------------------
1569 uu | string | string | UU codec (e.g. for email)
1570 base64 | string | string | base64 codec
Guido van Rossumc3415802001-06-06 13:30:54 +00001571 quopri | string | string | quoted-printable codec
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00001572 zlib | string | string | zlib compression
1573 hex | string | string | 2-byte hex codec
1574 rot-13 | string | Unicode | ROT-13 Unicode charmap codec
1575
Mark Hammond2a0af792001-05-14 03:09:36 +00001576- Some operating systems now support the concept of a default Unicode
1577 encoding for file system operations. Notably, Windows supports 'mbcs'
1578 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +00001579 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +00001580 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00001581
1582 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +00001583 functions that return filenames (such as os.listdir()) to return Python
1584 string objects pre-encoded using the default file system encoding for
1585 the platform. As this encoding is likely to be different from Python's
1586 default encoding, converting this name to a Unicode object before passing
1587 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +00001588 would attempt to use its default encoding (generally ASCII) rather than
1589 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00001590
Tim Petersa814db52001-05-14 07:05:58 +00001591 In general, this change simply removes surprises when working with
1592 Unicode and the file system, making these operations work as you expect,
1593 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +00001594 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +00001595
Tim Peters61dff2b2001-05-08 15:43:37 +00001596- Float (and complex) literals in source code were evaluated to full
1597 precision only when running from a .py file; the same code loaded from a
1598 .pyc (or .pyo) file could suffer numeric differences starting at about the
1599 12th significant decimal digit. For example, on a machine with IEEE-754
1600 floating arithmetic,
1601
1602 x = 9007199254740992.0
1603 print long(x)
1604
1605 printed 9007199254740992 if run directly from .py, but 9007199254740000
1606 if from a compiled (.pyc or .pyo) file. This was due to marshal using
1607 str(float) instead of repr(float) when building code objects. marshal
1608 now uses repr(float) instead, which should reproduce floats to full
1609 machine precision (assuming the platform C float<->string I/O conversion
1610 functions are of good quality).
1611
1612 This may cause floating-point results to change in some cases, and
1613 usually for the better, but may also cause numerically unstable
1614 algorithms to break.
1615
Tim Peters2f228e72001-05-13 00:19:31 +00001616- The implementation of dicts suffers fewer collisions, which has speed
1617 benefits. However, the order in which dict entries appear in dict.keys(),
1618 dict.values() and dict.items() may differ from previous releases for a
1619 given dict. Nothing is defined about this order, so no program should
1620 rely on it. Nevertheless, it's easy to write test cases that rely on the
1621 order by accident, typically because of printing the str() or repr() of a
1622 dict to an "expected results" file. See Lib/test/test_support.py's new
1623 sortdict(dict) function for a simple way to display a dict in sorted
1624 order.
1625
Tim Peters7a3bfc32001-06-12 01:22:22 +00001626- Many other small changes to dicts were made, resulting in faster
1627 operation along the most common code paths.
1628
Guido van Rossum10315822001-05-01 20:54:30 +00001629- Dictionary objects now support the "in" operator: "x in dict" means
1630 the same as dict.has_key(x).
1631
Barry Warsaw51acc8d2001-06-26 20:12:50 +00001632- The update() method of dictionaries now accepts generic mapping
1633 objects. Specifically the argument object must support the .keys()
1634 and __getitem__() methods. This allows you to say, for example,
1635 {}.update(UserDict())
1636
Guido van Rossum10315822001-05-01 20:54:30 +00001637- Iterators were added; this is a generalized way of providing values
1638 to a for loop. See PEP 234. There's a new built-in function iter()
1639 to return an iterator. There's a new protocol to get the next value
1640 from an iterator using the next() method (in Python) or the
1641 tp_iternext slot (in C). There's a new protocol to get iterators
1642 using the __iter__() method (in Python) or the tp_iter slot (in C).
1643 Iterating (i.e. a for loop) over a dictionary generates its keys.
1644 Iterating over a file generates its lines.
1645
Tim Petersf553f892001-05-01 20:45:31 +00001646- The following functions were generalized to work nicely with iterator
1647 arguments:
Tim Peterse63415e2001-05-08 04:38:29 +00001648 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +00001649 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
1650 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +00001651 join() method of strings
1652 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +00001653 'x in y' and 'x not in y' (PySequence_Contains() in C API)
1654 operator.countOf() (PySequence_Count() in C API)
Tim Petersd6d010b2001-06-21 02:49:55 +00001655 right-hand side of assignment statements with multiple targets, such as
1656 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +00001657
Tim Petersd85e1022001-05-11 21:51:48 +00001658- Accessing module attributes is significantly faster (for example,
1659 random.random or os.path or yourPythonModule.yourAttribute).
1660
Tim Peterse63415e2001-05-08 04:38:29 +00001661- Comparing dictionary objects via == and != is faster, and now works even
1662 if the keys and values don't support comparisons other than ==.
1663
Tim Peters95bf9392001-05-10 08:32:44 +00001664- Comparing dictionaries in ways other than == and != is slower: there were
1665 insecurities in the dict comparison implementation that could cause Python
1666 to crash if the element comparison routines for the dict keys and/or
1667 values mutated the dicts. Making the code bulletproof slowed it down.
1668
Tim Peterseb28ef22001-06-02 05:27:19 +00001669- Collisions in dicts are resolved via a new approach, which can help
1670 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +00001671 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +00001672 faster now. Thanks to Christian Tismer for pointing out the cause and
1673 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +00001674
Tim Peters52e155e2001-06-16 05:42:57 +00001675- repr() is much faster for large containers (dict, list, tuple).
1676
1677
Tim Petersa814db52001-05-14 07:05:58 +00001678Library
1679
Fred Drake960fdf92001-07-20 18:38:26 +00001680- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
1681 were added to the string module. These a locale-indenpendent
1682 constants, unlike letters, lowercase, and uppercase. These are now
1683 use in appropriate locations in the standard library.
1684
Martin v. Löwisf0473d52001-07-18 16:17:16 +00001685- The flags used in dlopen calls can now be configured using
1686 sys.setdlopenflags and queried using sys.getdlopenflags.
1687
Guido van Rossumc7e4aca2001-07-12 11:54:37 +00001688- Fredrik Lundh's xmlrpclib is now a standard library module. This
1689 provides full client-side XML-RPC support. In addition,
1690 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
1691 one asyncore-based). Thanks to Eric Raymond for the documentation.
1692
Guido van Rossum643d3912001-07-05 14:46:25 +00001693- The xrange() object is simplified: it no longer supports slicing,
1694 repetition, comparisons, efficient 'in' checking, the tolist()
1695 method, or the start, stop and step attributes. See PEP 260.
1696
Martin v. Löwisebf94db2001-06-06 06:25:40 +00001697- A new function fnmatch.filter to filter lists of file names was added.
1698
Barry Warsawffd674d2001-05-22 16:00:10 +00001699- calendar.py uses month and day names based on the current locale.
1700
Guido van Rossum2e0a6542001-05-15 02:14:44 +00001701- strop is now *really* obsolete (this was announced before with 1.6),
1702 and issues DeprecationWarning when used (except for the four items
1703 that are still imported into string.py).
1704
Tim Petersa814db52001-05-14 07:05:58 +00001705- Cookie.py now sorts key+value pairs by key in output strings.
1706
1707- pprint.isrecursive(object) didn't correctly identify recursive objects.
1708 Now it does.
1709
Tim Peters95b3f782001-05-14 18:39:41 +00001710- pprint functions now much faster for large containers (tuple, list, dict).
1711
Tim Peters7b9542a2001-06-10 23:40:19 +00001712- New 'q' and 'Q' format codes in the struct module, corresponding to C
1713 types "long long" and "unsigned long long" (on Windows, __int64). In
1714 native mode, these can be used only when the platform C compiler supports
1715 these types (when HAVE_LONG_LONG is #define'd by the Python config
1716 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +00001717 In standard mode, 'q' and 'Q' are supported on all platforms, and are
1718 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +00001719
Guido van Rossum83213cc2001-06-12 16:48:52 +00001720- The site module installs a new built-in function 'help' that invokes
1721 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
1722 it displays a message reminding the user to use 'help()' or
1723 'help(object)'.
1724
Tim Petersa814db52001-05-14 07:05:58 +00001725Tests
1726
1727- New test_mutants.py runs dict comparisons where the key and value
1728 comparison operators mutute the dicts randomly during comparison. This
1729 rapidly causes Python to crash under earlier releases (not for the faint
1730 of heart: it can also cause Win9x to freeze or reboot!).
1731
1732- New test_pprint.py verfies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +00001733 pprint.isreadable() return sensible results. Also verifies that simple
1734 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +00001735
Tim Peters4324aa32001-05-28 22:30:08 +00001736C API
1737
1738- Removed the unused last_is_sticky argument from the internal
1739 _PyTuple_Resize(). If this affects you, you were cheating.
1740
1741
Guido van Rossum55a78992001-07-17 17:22:32 +00001742======================================================================
1743
1744
Guido van Rossumffe13be2001-04-16 18:46:45 +00001745What's New in Python 2.1 (final)?
1746=================================
1747
1748We only changed a few things since the last release candidate, all in
1749Python library code:
1750
1751- A bug in the locale module was fixed that affected locales which
1752 define no grouping for numeric formatting.
1753
1754- A few bugs in the weakref module's implementations of weak
1755 dictionaries (WeakValueDictionary and WeakKeyDictionary) were fixed,
1756 and the test suite was updated to check for these bugs.
1757
1758- An old bug in the os.path.walk() function (introduced in Python
1759 2.0!) was fixed: a non-existent file would cause an exception
1760 instead of being ignored.
1761
1762- Fixed a few bugs in the new symtable module found by Neil Norwitz's
1763 PyChecker.
1764
1765
Guido van Rossum5b08f132001-04-16 02:05:23 +00001766What's New in Python 2.1c2?
1767===========================
Barry Warsaw11e89c72001-04-11 20:37:57 +00001768
Guido van Rossum5b08f132001-04-16 02:05:23 +00001769A flurry of small changes, and one showstopper fixed in the nick of
1770time made it necessary to release another release candidate. The list
1771here is the *complete* list of patches (except version updates):
Guido van Rossum4fb60362001-04-13 00:46:14 +00001772
Guido van Rossum5b08f132001-04-16 02:05:23 +00001773Core
Guido van Rossum4fb60362001-04-13 00:46:14 +00001774
Guido van Rossum5b08f132001-04-16 02:05:23 +00001775- Tim discovered a nasty bug in the dictionary code, caused by
1776 PyDict_Next() calling dict_resize(), and the GC code's use of
1777 PyDict_Next() violating an assumption in dict_items(). This was
1778 fixed with considerable amounts of band-aid, but the net effect is a
1779 saner and more robust implementation.
1780
1781- Made a bunch of symbols static that were accidentally global.
1782
1783Build and Ports
1784
1785- The setup.py script didn't check for a new enough version of zlib
1786 (1.1.3 is needed). Now it does.
1787
1788- Changed "make clean" target to also remove shared libraries.
1789
1790- Added a more general warning about the SGI Irix optimizer to README.
1791
1792Library
1793
1794- Fix a bug in urllib.basejoin("http://host", "../file.html") which
1795 omitted the slash between host and file.html.
1796
1797- The mailbox module's _Mailbox class contained a completely broken
1798 and undocumented seek() method. Ripped it out.
1799
1800- Fixed a bunch of typos in various library modules (urllib2, smtpd,
1801 sgmllib, netrc, chunk) found by Neil Norwitz's PyChecker.
1802
1803- Fixed a few last-minute bugs in unittest.
1804
1805Extensions
1806
1807- Reverted the patch to the OpenSSL code in socketmodule.c to support
1808 RAND_status() and the EGD, and the subsequent patch that tried to
1809 fix it for pre-0.9.5 versions; the problem with the patch is that on
1810 some systems it issues a warning whenever socket is imported, and
1811 that's unacceptable.
1812
1813Tests
1814
1815- Fixed the pickle tests to work with "import test.test_pickle".
1816
1817- Tweaked test_locale.py to actually run the test Windows.
1818
1819- In distutils/archive_util.py, call zipfile.ZipFile() with mode "w",
1820 not "wb" (which is not a valid mode at all).
1821
1822- Fix pstats browser crashes. Import readline if it exists to make
1823 the user interface nicer.
1824
1825- Add "import thread" to the top of test modules that import the
1826 threading module (test_asynchat and test_threadedtempfile). This
1827 prevents test failures caused by a broken threading module resulting
1828 from a previously caught failed import.
1829
1830- Changed test_asynchat.py to set the SO_REUSEADDR option; this was
1831 needed on some platforms (e.g. Solaris 8) when the tests are run
1832 twice in succession.
1833
1834- Skip rather than fail test_sunaudiodev if no audio device is found.
1835
1836
1837What's New in Python 2.1c1?
1838===========================
1839
1840This list was significantly updated when 2.1c2 was released; the 2.1c1
1841release didn't mention most changes that were actually part of 2.1c1:
1842
1843Legal
1844
1845- Copyright was assigned to the Python Software Foundation (PSF) and a
1846 PSF license (very similar to the CNRI license) was added.
1847
1848- The CNRI copyright notice was updated to include 2001.
1849
1850Core
Barry Warsaw11e89c72001-04-11 20:37:57 +00001851
Guido van Rossumc9932722001-04-12 02:31:27 +00001852- After a public outcry, assignment to __debug__ is no longer illegal;
1853 instead, a warning is issued. It will become illegal in 2.2.
1854
Guido van Rossum5b08f132001-04-16 02:05:23 +00001855- Fixed a core dump with "%#x" % 0, and changed the semantics so that
1856 "%#x" now always prepends "0x", even if the value is zero.
1857
1858- Fixed some nits in the bytecode compiler.
1859
1860- Fixed core dumps when calling certain kinds of non-functions.
1861
1862- Fixed various core dumps caused by reference count bugs.
1863
1864Build and Ports
1865
1866- Use INSTALL_SCRIPT to install script files.
1867
Guido van Rossum34d37dc2001-04-11 21:03:32 +00001868- New port: SCO Unixware 7, by Billy G. Allie.
1869
Guido van Rossum5b08f132001-04-16 02:05:23 +00001870- Updated RISCOS port.
1871
1872- Updated BeOS port and notes.
1873
1874- Various other porting problems resolved.
1875
1876Library
1877
1878- The TERMIOS and SOCKET modules are now truly obsolete and
1879 unnecessary. Their symbols are incorporated in the termios and
1880 socket modules.
1881
1882- Fixed some 64-bit bugs in pickle, cPickle, and struct, and added
1883 better tests for pickling.
1884
1885- threading: make Condition.wait() robust against KeyboardInterrupt.
1886
1887- zipfile: add support to zipfile to support opening an archive
1888 represented by an open file rather than a file name. Fix bug where
1889 the archive was not properly closed. Fixed a bug in this bugfix
1890 where flush() was called for a read-only file.
1891
1892- imputil: added an uninstall() method to the ImportManager.
1893
1894- Canvas: fixed bugs in lower() and tkraise() methods.
1895
1896- SocketServer: API change (added overridable close_request() method)
1897 so that the TCP server can explicitly close the request.
1898
1899- pstats: Eric Raymond added a simple interactive statistics browser,
1900 invoked when the module is run as a script.
1901
1902- locale: fixed a problem in format().
1903
1904- webbrowser: made it work when the BROWSER environment variable has a
1905 value like "/usr/bin/netscape". Made it auto-detect Konqueror for
1906 KDE 2. Fixed some other nits.
1907
1908- unittest: changes to allow using a different exception than
1909 AssertionError, and added a few more function aliases. Some other
1910 small changes.
1911
1912- urllib, urllib2: fixed redirect problems and a coupleof other nits.
1913
1914- asynchat: fixed a critical bug in asynchat that slipped through the
1915 2.1b2 release. Fixed another rare bug.
1916
1917- Fix some unqualified except: clauses (always a bad code example).
1918
1919XML
1920
1921- pyexpat: new API get_version_string().
1922
1923- Fixed some minidom bugs.
1924
1925Extensions
1926
1927- Fixed a core dump in _weakref. Removed the weakref.mapping()
1928 function (it adds nothing to the API).
1929
1930- Rationalized the use of header files in the readline module, to make
1931 it compile (albeit with some warnings) with the very recent readline
1932 4.2, without breaking for earlier versions.
1933
1934- Hopefully fixed a buffering problem in linuxaudiodev.
1935
1936- Attempted a fix to make the OpenSSL support in the socket module
1937 work again with pre-0.9.5 versions of OpenSSL.
1938
1939Tests
1940
1941- Added a test case for asynchat and asyncore.
1942
1943- Removed coupling between tests where one test failing could break
1944 another.
1945
1946Tools
1947
1948- Ping added an interactive help browser to pydoc, fixed some nits
1949 in the rest of the pydoc code, and added some features to his
1950 inspect module.
1951
1952- An updated python-mode.el version 4.1 which integrates Ken
1953 Manheimer's pdbtrack.el. This makes debugging Python code via pdb
1954 much nicer in XEmacs and Emacs. When stepping through your program
1955 with pdb, in either the shell window or the *Python* window, the
1956 source file and line will be tracked by an arrow. Very cool!
1957
1958- IDLE: syntax warnings in interactive mode are changed into errors.
1959
1960- Some improvements to Tools/webchecker (ignore some more URL types,
Tim Peters0e57abf2001-05-02 07:39:38 +00001961 follow some more links).
Guido van Rossum5b08f132001-04-16 02:05:23 +00001962
1963- Brought the Tools/compiler package up to date.
Guido van Rossum34d37dc2001-04-11 21:03:32 +00001964
Barry Warsaw11e89c72001-04-11 20:37:57 +00001965
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00001966What's New in Python 2.1 beta 2?
1967================================
1968
Guido van Rossum053ae352001-03-22 14:17:21 +00001969(Unlisted are many fixed bugs, more documentation, etc.)
1970
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00001971Core language, builtins, and interpreter
1972
Guido van Rossum053ae352001-03-22 14:17:21 +00001973- The nested scopes work (enabled by "from __future__ import
1974 nested_scopes") is completed; in particular, the future now extends
1975 into code executed through exec, eval() and execfile(), and into the
1976 interactive interpreter.
1977
1978- When calling a base class method (e.g. BaseClass.__init__(self)),
1979 this is now allowed even if self is not strictly spoken a class
1980 instance (e.g. when using metaclasses or the Don Beaudry hook).
1981
1982- Slice objects are now comparable but not hashable; this prevents
1983 dict[:] from being accepted but meaningless.
1984
1985- Complex division is now calculated using less braindead algorithms.
1986 This doesn't change semantics except it's more likely to give useful
1987 results in extreme cases. Complex repr() now uses full precision
1988 like float repr().
1989
1990- sgmllib.py now calls handle_decl() for simple <!...> declarations.
1991
Jeremy Hyltonf626db72001-03-23 14:18:27 +00001992- It is illegal to assign to the name __debug__, which is set when the
1993 interpreter starts. It is effectively a compile-time constant.
1994
1995- A warning will be issued if a global statement for a variable
1996 follows a use or assignment of that variable.
1997
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00001998Standard library
1999
Guido van Rossum053ae352001-03-22 14:17:21 +00002000- unittest.py, a unit testing framework by Steve Purcell (PyUNIT,
2001 inspired by JUnit), is now part of the standard library. You now
2002 have a choice of two testing frameworks: unittest requires you to
2003 write testcases as separate code, doctest gathers them from
2004 docstrings. Both approaches have their advantages and
2005 disadvantages.
2006
2007- A new module Tix was added, which wraps the Tix extension library
2008 for Tk. With that module, it is not necessary to statically link
2009 Tix with _tkinter, since Tix will be loaded with Tcl's "package
2010 require" command. See Demo/tix/.
2011
2012- tzparse.py is now obsolete.
2013
2014- In gzip.py, the seek() and tell() methods are removed -- they were
2015 non-functional anyway, and it's better if callers can test for their
2016 existence with hasattr().
2017
2018Python/C API
2019
2020- PyDict_Next(): it is now safe to call PyDict_SetItem() with a key
2021 that's already in the dictionary during a PyDict_Next() iteration.
2022 This used to fail occasionally when a dictionary resize operation
2023 could be triggered that would rehash all the keys. All other
2024 modifications to the dictionary are still off-limits during a
2025 PyDict_Next() iteration!
2026
2027- New extended APIs related to passing compiler variables around.
2028
2029- New abstract APIs PyObject_IsInstance(), PyObject_IsSubclass()
2030 implement isinstance() and issubclass().
2031
2032- Py_BuildValue() now has a "D" conversion to create a Python complex
2033 number from a Py_complex C value.
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00002034
Fred Drake4e262a92001-03-22 18:26:47 +00002035- Extensions types which support weak references must now set the
2036 field allocated for the weak reference machinery to NULL themselves;
2037 this is done to avoid the cost of checking each object for having a
2038 weakly referencable type in PyObject_INIT(), since most types are
2039 not weakly referencable.
2040
Jeremy Hyltonf626db72001-03-23 14:18:27 +00002041- PyFrame_FastToLocals() and PyFrame_LocalsToFast() copy bindings for
2042 free variables and cell variables to and from the frame's f_locals.
2043
2044- Variants of several functions defined in pythonrun.h have been added
2045 to support the nested_scopes future statement. The variants all end
2046 in Flags and take an extra argument, a PyCompilerFlags *; examples:
2047 PyRun_AnyFileExFlags(), PyRun_InteractiveLoopFlags(). These
2048 variants may be removed in Python 2.2, when nested scopes are
Tim Peters0e57abf2001-05-02 07:39:38 +00002049 mandatory.
Jeremy Hyltonf626db72001-03-23 14:18:27 +00002050
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +00002051Distutils
2052
2053- the sdist command now writes a PKG-INFO file, as described in PEP 241,
2054 into the release tree.
2055
Tim Peters0e57abf2001-05-02 07:39:38 +00002056- several enhancements to the bdist_wininst command from Thomas Heller
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +00002057 (an uninstaller, more customization of the installer's display)
2058
2059- from Jack Jansen: added Mac-specific code to generate a dialog for
2060 users to specify the command-line (because providing a command-line with
Tim Peters0e57abf2001-05-02 07:39:38 +00002061 MacPython is awkward). Jack also made various fixes for the Mac
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +00002062 and the Metrowerks compiler.
Tim Peters0e57abf2001-05-02 07:39:38 +00002063
2064- added 'platforms' and 'keywords' to the set of metadata that can be
2065 specified for a distribution.
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +00002066
2067- applied patches from Jason Tishler to make the compiler class work with
2068 Cygwin.
2069
2070
Tim Peters2fe289a2001-03-01 22:19:38 +00002071What's New in Python 2.1 beta 1?
2072================================
Tim Petersd66595f2001-02-04 03:09:53 +00002073
2074Core language, builtins, and interpreter
2075
Guido van Rossum9d0fbde2001-03-02 14:00:32 +00002076- Following an outcry from the community about the amount of code
2077 broken by the nested scopes feature introduced in 2.1a2, we decided
2078 to make this feature optional, and to wait until Python 2.2 (or at
2079 least 6 months) to make it standard. The option can be enabled on a
2080 per-module basis by adding "from __future__ import nested_scopes" at
2081 the beginning of a module (before any other statements, but after
2082 comments and an optional docstring). See PEP 236 (Back to the
2083 __future__) for a description of the __future__ statement. PEP 227
2084 (Statically Nested Scopes) has been updated to reflect this change,
2085 and to clarify the semantics in a number of endcases.
2086
2087- The nested scopes code, when enabled, has been hardened, and most
2088 bugs and memory leaks in it have been fixed.
2089
2090- Compile-time warnings are now generated for a number of conditions
2091 that will break or change in meaning when nested scopes are enabled:
2092
2093 - Using "from...import *" or "exec" without in-clause in a function
2094 scope that also defines a lambda or nested function with one or
2095 more free (non-local) variables. The presence of the import* or
2096 bare exec makes it impossible for the compiler to determine the
2097 exact set of local variables in the outer scope, which makes it
2098 impossible to determine the bindings for free variables in the
2099 inner scope. To avoid the warning about import *, change it into
2100 an import of explicitly name object, or move the import* statement
2101 to the global scope; to avoid the warning about bare exec, use
2102 exec...in... (a good idea anyway -- there's a possibility that
2103 bare exec will be deprecated in the future).
2104
2105 - Use of a global variable in a nested scope with the same name as a
2106 local variable in a surrounding scope. This will change in
2107 meaning with nested scopes: the name in the inner scope will
2108 reference the variable in the outer scope rather than the global
2109 of the same name. To avoid the warning, either rename the outer
2110 variable, or use a global statement in the inner function.
2111
Neil Schemenauera35c6882001-02-27 04:45:05 +00002112- An optional object allocator has been included. This allocator is
2113 optimized for Python objects and should be faster and use less memory
2114 than the standard system allocator. It is not enabled by default
2115 because of possible thread safety problems. The allocator is only
2116 protected by the Python interpreter lock and it is possible that some
2117 extension modules require a thread safe allocator. The object
2118 allocator can be enabled by providing the "--with-pymalloc" option to
2119 configure.
2120
Tim Petersd66595f2001-02-04 03:09:53 +00002121Standard library
2122
Martin v. Löwis2a5130e2001-02-27 04:21:58 +00002123- pyexpat now detects the expat version if expat.h defines it. A
2124 number of additional handlers are provided, which are only available
2125 since expat 1.95. In addition, the methods SetParamEntityParsing and
2126 GetInputContext of Parser objects are available with 1.95.x
2127 only. Parser objects now provide the ordered_attributes and
2128 specified_attributes attributes. A new module expat.model was added,
2129 which offers a number of additional constants if 1.95.x is used.
2130
2131- xml.dom offers the new functions registerDOMImplementation and
2132 getDOMImplementation.
2133
2134- xml.dom.minidom offers a toprettyxml method. A number of DOM
2135 conformance issues have been resolved. In particular, Element now
2136 has an hasAttributes method, and the handling of namespaces was
2137 improved.
2138
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +00002139- Ka-Ping Yee contributed two new modules: inspect.py, a module for
2140 getting information about live Python code, and pydoc.py, a module
2141 for interactively converting docstrings to HTML or text.
2142 Tools/scripts/pydoc, which is now automatically installed into
Tim Peters1eff7962001-03-01 02:31:33 +00002143 <prefix>/bin, uses pydoc.py to display documentation; try running
Guido van Rossume3955a82001-03-02 14:05:59 +00002144 "pydoc -h" for instructions. "pydoc -g" pops up a small GUI that
2145 lets you browse the module docstrings using a web browser.
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +00002146
Tim Peters1eff7962001-03-01 02:31:33 +00002147- New library module difflib.py, primarily packaging the SequenceMatcher
2148 class at the heart of the popular ndiff.py file-comparison tool.
2149
2150- doctest.py (a framework for verifying Python code examples in docstrings)
2151 is now part of the std library.
2152
Tim Petersd66595f2001-02-04 03:09:53 +00002153Windows changes
2154
Guido van Rossume3955a82001-03-02 14:05:59 +00002155- A new entry in the Start menu, "Module Docs", runs "pydoc -g" -- a
2156 small GUI that lets you browse the module docstrings using your
2157 default web browser.
2158
Tim Peters1eff7962001-03-01 02:31:33 +00002159- Import is now case-sensitive. PEP 235 (Import on Case-Insensitive
2160 Platforms) is implemented. See
2161
2162 http://python.sourceforge.net/peps/pep-0235.html
2163
2164 for full details, especially the "Current Lower-Left Semantics" section.
2165 The new Windows import rules are simpler than before:
2166
2167 A. If the PYTHONCASEOK environment variable exists, same as
2168 before: silently accept the first case-insensitive match of any
2169 kind; raise ImportError if none found.
2170
2171 B. Else search sys.path for the first case-sensitive match; raise
2172 ImportError if none found.
2173
2174 The same rules have been implented on other platforms with case-
2175 insensitive but case-preserving filesystems too (including Cygwin, and
2176 several flavors of Macintosh operating systems).
Tim Petersd66595f2001-02-04 03:09:53 +00002177
Tim Peters25a9ce32001-02-19 07:06:36 +00002178- winsound module: Under Win9x, winsound.Beep() now attempts to simulate
2179 what it's supposed to do (and does do under NT and 2000) via direct
2180 port manipulation. It's unknown whether this will work on all systems,
Tim Peters1eff7962001-03-01 02:31:33 +00002181 but it does work on my Win98SE systems now and was known to be useless on
Tim Peters25a9ce32001-02-19 07:06:36 +00002182 all Win9x systems before.
2183
Tim Peters1eff7962001-03-01 02:31:33 +00002184- Build: Subproject _test (effectively) renamed to _testcapi.
2185
Tim Peters2fe289a2001-03-01 22:19:38 +00002186New platforms
2187
2188- 2.1 should compile and run out of the box under MacOS X, even using HFS+.
2189 Thanks to Steven Majewski!
2190
2191- 2.1 should compile and run out of the box on Cygwin. Thanks to Jason
2192 Tishler!
2193
Guido van Rossum9089b272001-03-02 06:49:50 +00002194- 2.1 contains new files and patches for RISCOS, thanks to Dietmar
2195 Schwertberger! See RISCOS/README for more information -- it seems
2196 that because of the bizarre filename conventions on RISCOS, no port
Guido van Rossum49192142001-10-24 20:51:44 +00002197 to that platform is easy.
Guido van Rossum9089b272001-03-02 06:49:50 +00002198
Tim Peters25a9ce32001-02-19 07:06:36 +00002199
Tim Petersd7b5e882001-01-25 03:36:26 +00002200What's New in Python 2.1 alpha 2?
2201=================================
Tim Peters40ead762001-01-27 05:35:26 +00002202
Tim Petersd7b5e882001-01-25 03:36:26 +00002203Core language, builtins, and interpreter
2204
Jeremy Hylton4589bd82001-02-01 20:38:45 +00002205- Scopes nest. If a name is used in a function or class, but is not
2206 local, the definition in the nearest enclosing function scope will
2207 be used. One consequence of this change is that lambda statements
2208 could reference variables in the namespaces where the lambda is
2209 defined. In some unusual cases, this change will break code.
2210
2211 In all previous version of Python, names were resolved in exactly
2212 three namespaces -- the local namespace, the global namespace, and
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +00002213 the builtin namespace. According to this old definition, if a
Jeremy Hylton4589bd82001-02-01 20:38:45 +00002214 function A is defined within a function B, the names bound in B are
2215 not visible in A. The new rules make names bound in B visible in A,
2216 unless A contains a name binding that hides the binding in B.
2217
2218 Section 4.1 of the reference manual describes the new scoping rules
2219 in detail. The test script in Lib/test/test_scope.py demonstrates
2220 some of the effects of the change.
2221
2222 The new rules will cause existing code to break if it defines nested
2223 functions where an outer function has local variables with the same
2224 name as globals or builtins used by the inner function. Example:
2225
2226 def munge(str):
2227 def helper(x):
2228 return str(x)
2229 if type(str) != type(''):
2230 str = helper(str)
2231 return str.strip()
2232
2233 Under the old rules, the name str in helper() is bound to the
2234 builtin function str(). Under the new rules, it will be bound to
2235 the argument named str and an error will occur when helper() is
2236 called.
2237
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +00002238- The compiler will report a SyntaxError if "from ... import *" occurs
2239 in a function or class scope. The language reference has documented
2240 that this case is illegal, but the compiler never checked for it.
2241 The recent introduction of nested scope makes the meaning of this
2242 form of name binding ambiguous. In a future release, the compiler
2243 may allow this form when there is no possibility of ambiguity.
2244
Tim Peters40ead762001-01-27 05:35:26 +00002245- repr(string) is easier to read, now using hex escapes instead of octal,
2246 and using \t, \n and \r instead of \011, \012 and \015 (respectively):
2247
2248 >>> "\texample \r\n" + chr(0) + chr(255)
2249 '\texample \r\n\x00\xff' # in 2.1
2250 '\011example \015\012\000\377' # in 2.0
2251
Moshe Zadka6af0ce02001-01-29 06:41:00 +00002252- Functions are now compared and hashed by identity, not by value, since
2253 the func_code attribute is writable.
2254
Fred Drakefb9d7122001-02-01 20:00:40 +00002255- Weak references (PEP 205) have been added. This involves a few
2256 changes in the core, an extension module (_weakref), and a Python
2257 module (weakref). The weakref module is the public interface. It
2258 includes support for "explicit" weak references, proxy objects, and
2259 mappings with weakly held values.
2260
Jeremy Hylton0072d5a2001-02-01 22:53:15 +00002261- A 'continue' statement can now appear in a try block within the body
2262 of a loop. It is still not possible to use continue in a finally
Tim Peters9ea17ac2001-02-02 05:57:15 +00002263 clause.
Jeremy Hylton0072d5a2001-02-01 22:53:15 +00002264
Tim Petersd7b5e882001-01-25 03:36:26 +00002265Standard library
2266
Barry Warsaw30dbd142001-01-31 22:14:01 +00002267- mailbox.py now has a new class, PortableUnixMailbox which is
2268 identical to UnixMailbox but uses a more portable scheme for
2269 determining From_ separators. Also, the constructors for all the
2270 classes in this module have a new optional `factory' argument, which
2271 is a callable used when new message classes must be instantiated by
2272 the next() method.
2273
Tim Petersd7b5e882001-01-25 03:36:26 +00002274- random.py is now self-contained, and offers all the functionality of
2275 the now-deprecated whrandom.py. See the docs for details. random.py
2276 also supports new functions getstate() and setstate(), for saving
Tim Petersd52269b2001-01-25 06:23:18 +00002277 and restoring the internal state of the generator; and jumpahead(n),
2278 for quickly forcing the internal state to be the same as if n calls to
2279 random() had been made. The latter is particularly useful for multi-
2280 threaded programs, creating one instance of the random.Random() class for
2281 each thread, then using .jumpahead() to force each instance to use a
2282 non-overlapping segment of the full period.
Tim Petersd7b5e882001-01-25 03:36:26 +00002283
Tim Peters0de88fc2001-02-01 04:59:18 +00002284- random.py's seed() function is new. For bit-for-bit compatibility with
2285 prior releases, use the whseed function instead. The new seed function
2286 addresses two problems: (1) The old function couldn't produce more than
2287 about 2**24 distinct internal states; the new one about 2**45 (the best
2288 that can be done in the Wichmann-Hill generator). (2) The old function
2289 sometimes produced identical internal states when passed distinct
2290 integers, and there was no simple way to predict when that would happen;
2291 the new one guarantees to produce distinct internal states for all
2292 arguments in [0, 27814431486576L).
2293
Jeremy Hylton4c4fda02001-02-02 03:29:24 +00002294- The socket module now supports raw packets on Linux. The socket
2295 family is AF_PACKET.
2296
Tim Peters9ea17ac2001-02-02 05:57:15 +00002297- test_capi.py is a start at running tests of the Python C API. The tests
2298 are implemented by the new Modules/_testmodule.c.
2299
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +00002300- A new extension module, _symtable, provides provisional access to the
2301 internal symbol table used by the Python compiler. A higher-level
2302 interface will be added on top of _symtable in a future release.
2303
Andrew M. Kuchlingdebc3522001-02-22 15:53:21 +00002304- Removed the obsolete soundex module.
2305
Martin v. Löwis2a5130e2001-02-27 04:21:58 +00002306- xml.dom.minidom now uses the standard DOM exceptions. Node supports
2307 the isSameNode method; NamedNodeMap the get method.
2308
2309- xml.sax.expatreader supports the lexical handler property; it
2310 generates comment, startCDATA, and endCDATA events.
2311
Tim Petersee826f82001-01-31 19:39:44 +00002312Windows changes
2313
2314- Build procedure: the zlib project is built in a different way that
2315 ensures the zlib header files used can no longer get out of synch with
Tim Peters9ea17ac2001-02-02 05:57:15 +00002316 the zlib binary used. See PCbuild\readme.txt for details. Your old
2317 zlib-related directories can be deleted; you'll need to download fresh
2318 source for zlib and unpack it into a new directory.
Tim Petersee826f82001-01-31 19:39:44 +00002319
Tim Peters9ea17ac2001-02-02 05:57:15 +00002320- Build: New subproject _test for the benefit of test_capi.py (see above).
2321
Tim Petersb16c56f2001-02-02 21:24:51 +00002322- Build: New subproject _symtable, for new DLL _symtable.pyd (a nascent
2323 interface to some Python compiler internals).
2324
2325- Build: Subproject ucnhash is gone, since the code was folded into the
Tim Peters9ea17ac2001-02-02 05:57:15 +00002326 unicodedata subproject.
Tim Petersd7b5e882001-01-25 03:36:26 +00002327
Tim Petersa3a3a032000-11-30 05:22:44 +00002328What's New in Python 2.1 alpha 1?
2329=================================
2330
2331Core language, builtins, and interpreter
2332
Marc-André Lemburgebb195b2001-01-20 10:34:52 +00002333- There is a new Unicode companion to the PyObject_Str() API
2334 called PyObject_Unicode(). It behaves in the same way as the
2335 former, but assures that the returned value is an Unicode object
2336 (applying the usual coercion if necessary).
Marc-André Lemburgad7c98e2001-01-17 17:09:53 +00002337
Guido van Rossumf98eda02001-01-17 15:54:45 +00002338- The comparison operators support "rich comparison overloading" (PEP
2339 207). C extension types can provide a rich comparison function in
2340 the new tp_richcompare slot in the type object. The cmp() function
2341 and the C function PyObject_Compare() first try the new rich
2342 comparison operators before trying the old 3-way comparison. There
2343 is also a new C API PyObject_RichCompare() (which also falls back on
2344 the old 3-way comparison, but does not constrain the outcome of the
2345 rich comparison to a Boolean result).
2346
2347 The rich comparison function takes two objects (at least one of
2348 which is guaranteed to have the type that provided the function) and
2349 an integer indicating the opcode, which can be Py_LT, Py_LE, Py_EQ,
2350 Py_NE, Py_GT, Py_GE (for <, <=, ==, !=, >, >=), and returns a Python
2351 object, which may be NotImplemented (in which case the tp_compare
2352 slot function is used as a fallback, if defined).
2353
2354 Classes can overload individual comparison operators by defining one
2355 or more of the methods__lt__, __le__, __eq__, __ne__, __gt__,
Guido van Rossuma88479f2001-01-18 14:28:08 +00002356 __ge__. There are no explicit "reflected argument" versions of
2357 these; instead, __lt__ and __gt__ are each other's reflection,
2358 likewise for__le__ and __ge__; __eq__ and __ne__ are their own
2359 reflection (similar at the C level). No other implications are
2360 made; in particular, Python does not assume that == is the Boolean
2361 inverse of !=, or that < is the Boolean inverse of >=. This makes
2362 it possible to define types with partial orderings.
Guido van Rossumf98eda02001-01-17 15:54:45 +00002363
2364 Classes or types that want to implement (in)equality tests but not
2365 the ordering operators (i.e. unordered types) should implement ==
2366 and !=, and raise an error for the ordering operators.
2367
Guido van Rossuma88479f2001-01-18 14:28:08 +00002368 It is possible to define types whose rich comparison results are not
Guido van Rossumf98eda02001-01-17 15:54:45 +00002369 Boolean; e.g. a matrix type might want to return a matrix of bits
2370 for A < B, giving elementwise comparisons. Such types should ensure
2371 that any interpretation of their value in a Boolean context raises
2372 an exception, e.g. by defining __nonzero__ (or the tp_nonzero slot
2373 at the C level) to always raise an exception.
2374
Guido van Rossuma88479f2001-01-18 14:28:08 +00002375- Complex numbers use rich comparisons to define == and != but raise
2376 an exception for <, <=, > and >=. Unfortunately, this also means
2377 that cmp() of two complex numbers raises an exception when the two
2378 numbers differ. Since it is not mathematically meaningful to compare
2379 complex numbers except for equality, I hope that this doesn't break
2380 too much code.
2381
Tim Peters3389f192001-02-18 08:48:49 +00002382- The outcome of comparing non-numeric objects of different types is
Tim Peters14495852001-02-18 08:28:33 +00002383 not defined by the language, other than that it's arbitrary but
2384 consistent (see the Reference Manual). An implementation detail changed
2385 in 2.1a1 such that None now compares less than any other object. Code
2386 relying on this new behavior (like code that relied on the previous
2387 behavior) does so at its own risk.
2388
Barry Warsaw573b5412001-01-15 20:43:18 +00002389- Functions and methods now support getting and setting arbitrarily
2390 named attributes (PEP 232). Functions have a new __dict__
2391 (a.k.a. func_dict) which hold the function attributes. Methods get
2392 and set attributes on their underlying im_func. It is a TypeError
2393 to set an attribute on a bound method.
2394
Guido van Rossum051e3352001-01-15 19:11:10 +00002395- The xrange() object implementation has been improved so that
2396 xrange(sys.maxint) can be used on 64-bit platforms. There's still a
2397 limitation that in this case len(xrange(sys.maxint)) can't be
2398 calculated, but the common idiom "for i in xrange(sys.maxint)" will
2399 work fine as long as the index i doesn't actually reach 2**31.
2400 (Python uses regular ints for sequence and string indices; fixing
2401 that is much more work.)
2402
Guido van Rossum1cc8f832001-01-12 16:25:08 +00002403- Two changes to from...import:
2404
Guido van Rossumba381232001-02-03 15:06:40 +00002405 1) "from M import X" now works even if (after loading module M)
2406 sys.modules['M'] is not a real module; it's basically a getattr()
2407 operation with AttributeError exceptions changed into ImportError.
Guido van Rossum1cc8f832001-01-12 16:25:08 +00002408
2409 2) "from M import *" now looks for M.__all__ to decide which names to
2410 import; if M.__all__ doesn't exist, it uses M.__dict__.keys() but
2411 filters out names starting with '_' as before. Whether or not
2412 __all__ exists, there's no restriction on the type of M.
2413
Guido van Rossumf61f1662001-01-10 20:13:55 +00002414- File objects have a new method, xreadlines(). This is the fastest
2415 way to iterate over all lines in a file:
2416
2417 for line in file.xreadlines():
2418 ...do something to line...
2419
2420 See the xreadlines module (mentioned below) for how to do this for
2421 other file-like objects.
2422
2423- Even if you don't use file.xreadlines(), you may expect a speedup on
2424 line-by-line input. The file.readline() method has been optimized
Tim Petersf29b64d2001-01-15 06:33:19 +00002425 quite a bit in platform-specific ways: on systems (like Linux) that
2426 support flockfile(), getc_unlocked(), and funlockfile(), those are
2427 used by default. On systems (like Windows) without getc_unlocked(),
2428 a complicated (but still thread-safe) method using fgets() is used by
2429 default.
2430
Tim Petersd52269b2001-01-25 06:23:18 +00002431 You can force use of the fgets() method by #define'ing
2432 USE_FGETS_IN_GETLINE at build time (it may be faster than
Tim Petersf29b64d2001-01-15 06:33:19 +00002433 getc_unlocked()).
2434
Tim Petersd52269b2001-01-25 06:23:18 +00002435 You can force fgets() not to be used by #define'ing
2436 DONT_USE_FGETS_IN_GETLINE (this is the first thing to try if std test
Tim Petersf29b64d2001-01-15 06:33:19 +00002437 test_bufio.py fails -- and let us know if it does!).
2438
2439- In addition, the fileinput module, while still slower than the other
2440 methods on most platforms, has been sped up too, by using
2441 file.readlines(sizehint).
Guido van Rossumf61f1662001-01-10 20:13:55 +00002442
2443- Support for run-time warnings has been added, including a new
2444 command line option (-W) to specify the disposition of warnings.
2445 See the description of the warnings module below.
2446
2447- Extensive changes have been made to the coercion code. This mostly
2448 affects extension modules (which can now implement mixed-type
2449 numerical operators without having to use coercion), but
2450 occasionally, in boundary cases the coercion semantics have changed
2451 subtly. Since this was a terrible gray area of the language, this
Guido van Rossumae72d872001-01-11 15:00:14 +00002452 is considered an improvement. Also note that __rcmp__ is no longer
Guido van Rossumf61f1662001-01-10 20:13:55 +00002453 supported -- instead of calling __rcmp__, __cmp__ is called with
Guido van Rossuma88479f2001-01-18 14:28:08 +00002454 reflected arguments.
Guido van Rossumf61f1662001-01-10 20:13:55 +00002455
Guido van Rossumf98eda02001-01-17 15:54:45 +00002456- In connection with the coercion changes, a new built-in singleton
2457 object, NotImplemented is defined. This can be returned for
2458 operations that wish to indicate they are not implemented for a
2459 particular combination of arguments. From C, this is
2460 Py_NotImplemented.
2461
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +00002462- The interpreter accepts now bytecode files on the command line even
2463 if they do not have a .pyc or .pyo extension. On Linux, after executing
2464
Martin v. Löwise214baa2001-02-04 22:37:56 +00002465import imp,sys,string
2466magic = string.join(["\\x%.2x" % ord(c) for c in imp.get_magic()],"")
2467reg = ':pyc:M::%s::%s:' % (magic, sys.executable)
2468open("/proc/sys/fs/binfmt_misc/register","wb").write(reg)
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +00002469
2470 any byte code file can be used as an executable (i.e. as an argument
2471 to execve(2)).
2472
Tim Peters9940b802000-12-01 07:59:35 +00002473- %[xXo] formats of negative Python longs now produce a sign
Tim Petersa3a3a032000-11-30 05:22:44 +00002474 character. In 1.6 and earlier, they never produced a sign,
2475 and raised an error if the value of the long was too large
2476 to fit in a Python int. In 2.0, they produced a sign if and
2477 only if too large to fit in an int. This was inconsistent
2478 across platforms (because the size of an int varies across
2479 platforms), and inconsistent with hex() and oct(). Example:
2480
2481 >>> "%x" % -0x42L
Tim Peters9940b802000-12-01 07:59:35 +00002482 '-42' # in 2.1
Tim Petersa3a3a032000-11-30 05:22:44 +00002483 'ffffffbe' # in 2.0 and before, on 32-bit machines
2484 >>> hex(-0x42L)
2485 '-0x42L' # in all versions of Python
2486
Tim Peters9940b802000-12-01 07:59:35 +00002487 The behavior of %d formats for negative Python longs remains
2488 the same as in 2.0 (although in 1.6 and before, they raised
2489 an error if the long didn't fit in a Python int).
2490
2491 %u formats don't make sense for Python longs, but are allowed
2492 and treated the same as %d in 2.1. In 2.0, a negative long
2493 formatted via %u produced a sign if and only if too large to
2494 fit in an int. In 1.6 and earlier, a negative long formatted
2495 via %u raised an error if it was too big to fit in an int.
2496
Guido van Rossum3661d392000-12-12 22:10:31 +00002497- Dictionary objects have an odd new method, popitem(). This removes
2498 an arbitrary item from the dictionary and returns it (in the form of
2499 a (key, value) pair). This can be useful for algorithms that use a
2500 dictionary as a bag of "to do" items and repeatedly need to pick one
2501 item. Such algorithms normally end up running in quadratic time;
2502 using popitem() they can usually be made to run in linear time.
2503
Tim Peters36cdad12000-12-29 02:06:45 +00002504Standard library
2505
Thomas Woutersfe385252001-01-19 23:16:56 +00002506- In the time module, the time argument to the functions strftime,
2507 localtime, gmtime, asctime and ctime is now optional, defaulting to
2508 the current time (in the local timezone).
2509
Guido van Rossumda91f222001-01-15 16:36:08 +00002510- The ftplib module now defaults to passive mode, which is deemed a
2511 more useful default given that clients are often inside firewalls
2512 these days. Note that this could break if ftplib is used to connect
2513 to a *server* that is inside a firewall, from outside; this is
2514 expected to be a very rare situation. To fix that, you can call
2515 ftp.set_pasv(0).
2516
Martin v. Löwis10a27872001-01-13 09:54:41 +00002517- The module site now treats .pth files not only for path configuration,
2518 but also supports extensions to the initialization code: Lines starting
2519 with import are executed.
2520
Guido van Rossumf61f1662001-01-10 20:13:55 +00002521- There's a new module, warnings, which implements a mechanism for
2522 issuing and filtering warnings. There are some new built-in
2523 exceptions that serve as warning categories, and a new command line
2524 option, -W, to control warnings (e.g. -Wi ignores all warnings, -We
2525 turns warnings into errors). warnings.warn(message[, category])
2526 issues a warning message; this can also be called from C as
2527 PyErr_Warn(category, message).
2528
2529- A new module xreadlines was added. This exports a single factory
2530 function, xreadlines(). The intention is that this code is the
2531 absolutely fastest way to iterate over all lines in an open
2532 file(-like) object:
2533
2534 import xreadlines
2535 for line in xreadlines.xreadlines(file):
2536 ...do something to line...
2537
2538 This is equivalent to the previous the speed record holder using
2539 file.readlines(sizehint). Note that if file is a real file object
2540 (as opposed to a file-like object), this is equivalent:
2541
2542 for line in file.xreadlines():
2543 ...do something to line...
2544
Tim Peters36cdad12000-12-29 02:06:45 +00002545- The bisect module has new functions bisect_left, insort_left,
2546 bisect_right and insort_right. The old names bisect and insort
2547 are now aliases for bisect_right and insort_right. XXX_right
2548 and XXX_left methods differ in what happens when the new element
2549 compares equal to one or more elements already in the list: the
2550 XXX_left methods insert to the left, the XXX_right methods to the
Tim Peters742bb6f2001-01-05 08:05:32 +00002551 right. Code that doesn't care where equal elements end up should
2552 continue to use the old, short names ("bisect" and "insort").
Tim Peters36cdad12000-12-29 02:06:45 +00002553
Andrew M. Kuchlingf6f3a892001-01-13 14:53:34 +00002554- The new curses.panel module wraps the panel library that forms part
2555 of SYSV curses and ncurses. Contributed by Thomas Gellekum.
2556
Guido van Rossumf61f1662001-01-10 20:13:55 +00002557- The SocketServer module now sets the allow_reuse_address flag by
2558 default in the TCPServer class.
2559
2560- A new function, sys._getframe(), returns the stack frame pointer of
2561 the caller. This is intended only as a building block for
2562 higher-level mechanisms such as string interpolation.
2563
Martin v. Löwis2a5130e2001-02-27 04:21:58 +00002564- The pyexpat module supports a number of new handlers, which are
2565 available only in expat 1.2. If invocation of a callback fails, it
2566 will report an additional frame in the traceback. Parser objects
2567 participate now in garbage collection. If expat reports an unknown
2568 encoding, pyexpat will try to use a Python codec; that works only
2569 for single-byte charsets. The parser type objects is exposed as
2570 XMLParserObject.
2571
2572- xml.dom now offers standard definitions for symbolic node type and
2573 exception code constants, and a hierarchy of DOM exceptions. minidom
2574 was adjusted to use them.
2575
2576- The conformance of xml.dom.minidom to the DOM specification was
2577 improved. It detects a number of additional error cases; the
2578 previous/next relationship works even when the tree is modified;
2579 Node supports the normalize() method; NamedNodeMap, DocumentType and
2580 DOMImplementation classes were added; Element supports the
2581 hasAttribute and hasAttributeNS methods; and Text supports the splitText
2582 method.
2583
Guido van Rossumf61f1662001-01-10 20:13:55 +00002584Build issues
2585
Guido van Rossum1e33bdc2001-01-23 03:17:00 +00002586- For Unix (and Unix-compatible) builds, configuration and building of
2587 extension modules is now greatly automated. Rather than having to
2588 edit the Modules/Setup file to indicate which modules should be
2589 built and where their include files and libraries are, a
2590 distutils-based setup.py script now takes care of building most
2591 extension modules. All extension modules built this way are built
2592 as shared libraries. Only a few modules that must be linked
2593 statically are still listed in the Setup file; you won't need to
2594 edit their configuration.
2595
2596- Python should now build out of the box on Cygwin. If it doesn't,
2597 mail to Jason Tishler (jlt63 at users.sourceforge.net).
Guido van Rossumf61f1662001-01-10 20:13:55 +00002598
2599- Python now always uses its own (renamed) implementation of getopt()
2600 -- there's too much variation among C library getopt()
2601 implementations.
2602
2603- C++ compilers are better supported; the CXX macro is always set to a
2604 C++ compiler if one is found.
Tim Peters36cdad12000-12-29 02:06:45 +00002605
Tim Petersd92dfe02000-12-12 01:18:41 +00002606Windows changes
2607
2608- select module: By default under Windows, a select() call
2609 can specify no more than 64 sockets. Python now boosts
2610 this Microsoft default to 512. If you need even more than
2611 that, see the MS docs (you'll need to #define FD_SETSIZE
2612 and recompile Python from source).
2613
Guido van Rossumf61f1662001-01-10 20:13:55 +00002614- Support for Windows 3.1, DOS and OS/2 is gone. The Lib/dos-8x3
2615 subdirectory is no more!
2616
Tim Petersa3a3a032000-11-30 05:22:44 +00002617
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002618What's New in Python 2.0?
Fred Drake1a640502000-10-16 20:27:25 +00002619=========================
Guido van Rossum61000331997-08-15 04:39:58 +00002620
Guido van Rossum8ed602b2000-09-01 22:34:33 +00002621Below is a list of all relevant changes since release 1.6. Older
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002622changes are in the file HISTORY. If you are making the jump directly
2623from Python 1.5.2 to 2.0, make sure to read the section for 1.6 in the
2624HISTORY file! Many important changes listed there.
Guido van Rossum61000331997-08-15 04:39:58 +00002625
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002626Alternatively, a good overview of the changes between 1.5.2 and 2.0 is
2627the document "What's New in Python 2.0" by Kuchling and Moshe Zadka:
2628http://starship.python.net/crew/amk/python/writing/new-python/.
Guido van Rossum1f83cce1997-10-06 21:04:35 +00002629
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002630--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)
Guido van Rossum437cfe81999-04-08 20:17:57 +00002631
2632======================================================================
2633
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002634What's new in 2.0 (since release candidate 1)?
2635==============================================
2636
2637Standard library
2638
2639- The copy_reg module was modified to clarify its intended use: to
2640 register pickle support for extension types, not for classes.
2641 pickle() will raise a TypeError if it is passed a class.
2642
2643- Fixed a bug in gettext's "normalize and expand" code that prevented
2644 it from finding an existing .mo file.
2645
2646- Restored support for HTTP/0.9 servers in httplib.
2647
Tim Peters989b7b92000-10-16 20:24:53 +00002648- The math module was changed to stop raising OverflowError in case of
2649 underflow, and return 0 instead in underflow cases. Whether Python
2650 used to raise OverflowError in case of underflow was platform-
2651 dependent (it did when the platform math library set errno to ERANGE
2652 on underflow).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002653
2654- Fixed a bug in StringIO that occurred when the file position was not
2655 at the end of the file and write() was called with enough data to
2656 extend past the end of the file.
2657
2658- Fixed a bug that caused Tkinter error messages to get lost on
2659 Windows. The bug was fixed by replacing direct use of
2660 interp->result with Tcl_GetStringResult(interp).
2661
2662- Fixed bug in urllib2 that caused it to fail when it received an HTTP
2663 redirect response.
2664
2665- Several changes were made to distutils: Some debugging code was
2666 removed from util. Fixed the installer used when an external zip
2667 program (like WinZip) is not found; the source code for this
2668 installer is in Misc/distutils. check_lib() was modified to behave
2669 more like AC_CHECK_LIB by add other_libraries() as a parameter. The
2670 test for whether installed modules are on sys.path was changed to
2671 use both normcase() and normpath().
2672
Jeremy Hyltond867a2c2000-10-16 20:41:38 +00002673- Several minor bugs were fixed in the xml package (the minidom,
2674 pulldom, expatreader, and saxutils modules).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002675
2676- The regression test driver (regrtest.py) behavior when invoked with
2677 -l changed: It now reports a count of objects that are recognized as
2678 garbage but not freed by the garbage collector.
2679
Tim Peters989b7b92000-10-16 20:24:53 +00002680- The regression test for the math module was changed to test
2681 exceptional behavior when the test is run in verbose mode. Python
2682 cannot yet guarantee consistent exception behavior across platforms,
2683 so the exception part of test_math is run only in verbose mode, and
2684 may fail on your platform.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002685
2686Internals
2687
2688- PyOS_CheckStack() has been disabled on Win64, where it caused
2689 test_sre to fail.
2690
2691Build issues
2692
2693- Changed compiler flags, so that gcc is always invoked with -Wall and
2694 -Wstrict-prototypes. Users compiling Python with GCC should see
2695 exactly one warning, except if they have passed configure the
Tim Peters989b7b92000-10-16 20:24:53 +00002696 --with-pydebug flag. The expected warning is for getopt() in
Tim Petersadfb94f2000-10-16 20:51:33 +00002697 Modules/main.c. This warning will be fixed for Python 2.1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002698
Tim Petersa3a3a032000-11-30 05:22:44 +00002699- Fixed configure to add -threads argument during linking on OSF1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002700
2701Tools and other miscellany
2702
2703- The compiler in Tools/compiler was updated to support the new
2704 language features introduced in 2.0: extended print statement, list
2705 comprehensions, and augmented assignments. The new compiler should
2706 also be backwards compatible with Python 1.5.2; the compiler will
2707 always generate code for the version of the interpreter it runs
Tim Petersa3a3a032000-11-30 05:22:44 +00002708 under.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002709
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002710What's new in 2.0 release candidate 1 (since beta 2)?
2711=====================================================
2712
Jeremy Hylton6040aaa2000-10-09 21:27:22 +00002713What is release candidate 1?
2714
2715We believe that release candidate 1 will fix all known bugs that we
2716intend to fix for the 2.0 final release. This release should be a bit
2717more stable than the previous betas. We would like to see even more
2718widespread testing before the final release, so we are producing this
2719release candidate. The final release will be exactly the same unless
2720any show-stopping (or brown bag) bugs are found by testers of the
2721release candidate.
2722
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002723All the changes since the last beta release are bug fixes or changes
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002724to support building Python for specific platforms.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002725
2726Core language, builtins, and interpreter
2727
2728- A bug that caused crashes when __coerce__ was used with augmented
2729 assignment, e.g. +=, was fixed.
2730
2731- Raise ZeroDivisionError when raising zero to a negative number,
2732 e.g. 0.0 ** -2.0. Note that math.pow is unrelated to the builtin
2733 power operator and the result of math.pow(0.0, -2.0) will vary by
2734 platform. On Linux, it raises a ValueError.
2735
2736- A bug in Unicode string interpolation was fixed that occasionally
2737 caused errors with formats including "%%". For example, the
2738 following expression "%% %s" % u"abc" no longer raises a TypeError.
2739
2740- Compilation of deeply nested expressions raises MemoryError instead
2741 of SyntaxError, e.g. eval("[" * 50 + "]" * 50).
2742
2743- In 2.0b2 on Windows, the interpreter wrote .pyc files in text mode,
2744 rendering them useless. They are now written in binary mode again.
2745
2746Standard library
2747
2748- Keyword arguments are now accepted for most pattern and match object
2749 methods in SRE, the standard regular expression engine.
2750
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002751- In SRE, fixed error with negative lookahead and lookbehind that
Jeremy Hylton32e20ff2000-10-09 19:48:11 +00002752 manifested itself as a runtime error in patterns like "(?<!abc)(def)".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002753
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002754- Several bugs in the Unicode handling and error handling in _tkinter
2755 were fixed.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002756
2757- Fix memory management errors in Merge() and Tkapp_Call() routines.
2758
2759- Several changes were made to cStringIO to make it compatible with
2760 the file-like object interface and with StringIO. If operations are
2761 performed on a closed object, an exception is raised. The truncate
2762 method now accepts a position argument and readline accepts a size
Tim Petersa3a3a032000-11-30 05:22:44 +00002763 argument.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002764
2765- There were many changes made to the linuxaudiodev module and its
2766 test suite; as a result, a short, unexpected audio sample should now
Tim Petersa3a3a032000-11-30 05:22:44 +00002767 play when the regression test is run.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002768
2769 Note that this module is named poorly, because it should work
2770 correctly on any platform that supports the Open Sound System
Tim Petersa3a3a032000-11-30 05:22:44 +00002771 (OSS).
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002772
2773 The module now raises exceptions when errors occur instead of
2774 crashing. It also defines the AFMT_A_LAW format (logarithmic A-law
2775 audio) and defines a getptr() method that calls the
2776 SNDCTL_DSP_GETxPTR ioctl defined in the OSS Programmer's Guide.
2777
2778- The library_version attribute, introduced in an earlier beta, was
2779 removed because it can not be supported with early versions of the C
2780 readline library, which provides no way to determine the version at
2781 compile-time.
2782
2783- The binascii module is now enabled on Win64.
2784
Tim Peters46446d62000-10-09 21:19:31 +00002785- tokenize.py no longer suffers "recursion depth" errors when parsing
2786 programs with very long string literals.
2787
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002788Internals
2789
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002790- Fixed several buffer overflow vulnerabilities in calculate_path(),
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002791 which is called when the interpreter starts up to determine where
2792 the standard library is installed. These vulnerabilities affect all
2793 previous versions of Python and can be exploited by setting very
2794 long values for PYTHONHOME or argv[0]. The risk is greatest for a
2795 setuid Python script, although use of the wrapper in
2796 Misc/setuid-prog.c will eliminate the vulnerability.
2797
2798- Fixed garbage collection bugs in instance creation that were
2799 triggered when errors occurred during initialization. The solution,
2800 applied in cPickle and in PyInstance_New(), is to call
2801 PyObject_GC_Init() after the initialization of the object's
2802 container attributes is complete.
2803
2804- pyexpat adds definitions of PyModule_AddStringConstant and
2805 PyModule_AddObject if the Python version is less than 2.0, which
2806 provides compatibility with PyXML on Python 1.5.2.
2807
2808- If the platform has a bogus definition for LONG_BIT (the number of
2809 bits in a long), an error will be reported at compile time.
2810
2811- Fix bugs in _PyTuple_Resize() which caused hard-to-interpret garbage
2812 collection crashes and possibly other, unreported crashes.
2813
2814- Fixed a memory leak in _PyUnicode_Fini().
2815
2816Build issues
2817
2818- configure now accepts a --with-suffix option that specifies the
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002819 executable suffix. This is useful for builds on Cygwin and Mac OS
Tim Petersa3a3a032000-11-30 05:22:44 +00002820 X, for example.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002821
2822- The mmap.PAGESIZE constant is now initialized using sysconf when
2823 possible, which eliminates a dependency on -lucb for Reliant UNIX.
2824
2825- The md5 file should now compile on all platforms.
2826
2827- The select module now compiles on platforms that do not define
2828 POLLRDNORM and related constants.
2829
2830- Darwin (Mac OS X): Initial support for static builds on this
Tim Petersa3a3a032000-11-30 05:22:44 +00002831 platform.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002832
Jeremy Hylton10921202000-10-09 18:34:12 +00002833- BeOS: A number of changes were made to the build and installation
2834 process. ar-fake now operates on a directory of object files.
2835 dl_export.h is gone, and its macros now appear on the mwcc command
2836 line during build on PPC BeOS.
2837
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002838- Platform directory in lib/python2.0 is "plat-beos5" (or
Jeremy Hylton10921202000-10-09 18:34:12 +00002839 "plat-beos4", if building on BeOS 4.5), rather than "plat-beos".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002840
2841- Cygwin: Support for shared libraries, Tkinter, and sockets.
2842
2843- SunOS 4.1.4_JL: Fix test for directory existence in configure.
2844
2845Tools and other miscellany
2846
2847- Removed debugging prints from main used with freeze.
2848
Tim Peters46446d62000-10-09 21:19:31 +00002849- IDLE auto-indent no longer crashes when it encounters Unicode
2850 characters.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002851
2852What's new in 2.0 beta 2 (since beta 1)?
2853========================================
2854
2855Core language, builtins, and interpreter
2856
Tim Peters482c0212000-09-26 06:33:09 +00002857- Add support for unbounded ints in %d,i,u,x,X,o formats; for example
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002858 "%d" % 2L**64 == "18446744073709551616".
Jeremy Hylton1b618592000-09-26 05:32:36 +00002859
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002860- Add -h and -V command line options to print the usage message and
2861 Python version number and exit immediately.
2862
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002863- eval() and exec accept Unicode objects as code parameters.
2864
2865- getattr() and setattr() now also accept Unicode objects for the
2866 attribute name, which are converted to strings using the default
2867 encoding before lookup.
2868
2869- Multiplication on string and Unicode now does proper bounds
2870 checking; e.g. 'a' * 65536 * 65536 will raise ValueError, "repeated
2871 string is too long."
2872
2873- Better error message when continue is found in try statement in a
Tim Petersa3a3a032000-11-30 05:22:44 +00002874 loop.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002875
Jeremy Hylton1b618592000-09-26 05:32:36 +00002876
2877Standard library and extensions
2878
Guido van Rossum5b08f132001-04-16 02:05:23 +00002879- socket module: the OpenSSL code now adds support for RAND_status()
2880 and EGD (Entropy Gathering Device).
2881
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002882- array: reverse() method of array now works. buffer_info() now does
Jeremy Hylton1b618592000-09-26 05:32:36 +00002883 argument checking; it still takes no arguments.
2884
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002885- asyncore/asynchat: Included most recent version from Sam Rushing.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002886
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002887- cgi: Accept '&' or ';' as separator characters when parsing form data.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002888
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002889- CGIHTTPServer: Now works on Windows (and perhaps even Mac).
Jeremy Hylton1b618592000-09-26 05:32:36 +00002890
2891- ConfigParser: When reading the file, options spelled in upper case
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002892 letters are now correctly converted to lowercase.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002893
2894- copy: Copy Unicode objects atomically.
2895
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002896- cPickle: Fail gracefully when copy_reg can't be imported.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002897
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002898- cStringIO: Implemented readlines() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002899
Fred Drake67233bc2000-09-26 16:40:27 +00002900- dbm: Add get() and setdefault() methods to dbm object. Add constant
2901 `library' to module that names the library used. Added doc strings
2902 and method names to error messages. Uses configure to determine
2903 which ndbm.h file to include; Berkeley DB's nbdm and GDBM's ndbm is
2904 now available options.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002905
2906- distutils: Update to version 0.9.3.
2907
2908- dl: Add several dl.RTLD_ constants.
2909
2910- fpectl: Now supported on FreeBSD.
2911
2912- gc: Add DEBUG_SAVEALL option. When enabled all garbage objects
2913 found by the collector will be saved in gc.garbage. This is useful
2914 for debugging a program that creates reference cycles.
2915
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002916- httplib: Three changes: Restore support for set_debuglevel feature
Jeremy Hylton1b618592000-09-26 05:32:36 +00002917 of HTTP class. Do not close socket on zero-length response. Do not
2918 crash when server sends invalid content-length header.
2919
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002920- mailbox: Mailbox class conforms better to qmail specifications.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002921
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002922- marshal: When reading a short, sign-extend on platforms where shorts
2923 are bigger than 16 bits. When reading a long, repair the unportable
2924 sign extension that was being done for 64-bit machines. (It assumed
2925 that signed right shift sign-extends.)
2926
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002927- operator: Add contains(), invert(), __invert__() as aliases for
2928 __contains__(), inv(), and __inv__() respectively.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002929
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002930- os: Add support for popen2() and popen3() on all platforms where
2931 fork() exists. (popen4() is still in the works.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00002932
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002933- os: (Windows only:) Add startfile() function that acts like double-
Tim Peters482c0212000-09-26 06:33:09 +00002934 clicking on a file in Explorer (or passing the file name to the
2935 DOS "start" command).
Jeremy Hylton1b618592000-09-26 05:32:36 +00002936
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002937- os.path: (Windows, DOS:) Treat trailing colon correctly in
Tim Peters482c0212000-09-26 06:33:09 +00002938 os.path.join. os.path.join("a:", "b") yields "a:b".
Jeremy Hylton1b618592000-09-26 05:32:36 +00002939
2940- pickle: Now raises ValueError when an invalid pickle that contains
2941 a non-string repr where a string repr was expected. This behavior
2942 matches cPickle.
2943
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002944- posixfile: Remove broken __del__() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002945
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002946- py_compile: support CR+LF line terminators in source file.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002947
2948- readline: Does not immediately exit when ^C is hit when readline and
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002949 threads are configured. Adds definition of rl_library_version. (The
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002950 latter addition requires GNU readline 2.2 or later.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00002951
2952- rfc822: Domain literals returned by AddrlistClass method
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002953 getdomainliteral() are now properly wrapped in brackets.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002954
2955- site: sys.setdefaultencoding() should only be called in case the
Tim Peters482c0212000-09-26 06:33:09 +00002956 standard default encoding ("ascii") is changed. This saves quite a
Jeremy Hylton1b618592000-09-26 05:32:36 +00002957 few cycles during startup since the first call to
2958 setdefaultencoding() will initialize the codec registry and the
2959 encodings package.
2960
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002961- socket: Support for size hint in readlines() method of object returned
2962 by makefile().
Jeremy Hylton1b618592000-09-26 05:32:36 +00002963
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002964- sre: Added experimental expand() method to match objects. Does not
Jeremy Hylton625915e2000-10-02 13:43:33 +00002965 use buffer interface on Unicode strings. Does not hang if group id
Jeremy Hylton1b618592000-09-26 05:32:36 +00002966 is followed by whitespace.
2967
Tim Petersa3a3a032000-11-30 05:22:44 +00002968- StringIO: Size hint in readlines() is now supported as documented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002969
2970- struct: Check ranges for bytes and shorts.
2971
2972- urllib: Improved handling of win32 proxy settings. Fixed quote and
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002973 quote_plus functions so that the always encode a comma.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002974
2975- Tkinter: Image objects are now guaranteed to have unique ids. Set
2976 event.delta to zero if Tk version doesn't support mousewheel.
2977 Removed some debugging prints.
2978
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002979- UserList: now implements __contains__().
Jeremy Hylton1b618592000-09-26 05:32:36 +00002980
Fred Drake67233bc2000-09-26 16:40:27 +00002981- webbrowser: On Windows, use os.startfile() instead of os.popen(),
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002982 which works around a bug in Norton AntiVirus 2000 that leads directly
2983 to a Blue Screen freeze.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002984
2985- xml: New version detection code allows PyXML to override standard
2986 XML package if PyXML version is greater than 0.6.1.
2987
Fred Drake64bb3802000-09-26 16:21:35 +00002988- xml.dom: DOM level 1 support for basic XML. Includes xml.dom.minidom
2989 (conventional DOM), and xml.dom.pulldom, which allows building the DOM
2990 tree only for nodes which are sufficiently interesting to a specific
2991 application. Does not provide the HTML-specific extensions. Still
2992 undocumented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002993
Fred Drake64bb3802000-09-26 16:21:35 +00002994- xml.sax: SAX 2 support for Python, including all the handler
2995 interfaces needed to process XML 1.0 compliant XML. Some
2996 documentation is already available.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002997
Fred Drake64bb3802000-09-26 16:21:35 +00002998- pyexpat: Renamed to xml.parsers.expat since this is part of the new,
2999 packagized XML support.
Jeremy Hylton1b618592000-09-26 05:32:36 +00003000
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003001
Jeremy Hylton1b618592000-09-26 05:32:36 +00003002C API
3003
3004- Add three new convenience functions for module initialization --
3005 PyModule_AddObject(), PyModule_AddIntConstant(), and
3006 PyModule_AddStringConstant().
3007
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003008- Cleaned up definition of NULL in C source code; all definitions were
Jeremy Hylton1b618592000-09-26 05:32:36 +00003009 removed and add #error to Python.h if NULL isn't defined after
3010 #include of stdio.h.
3011
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003012- Py_PROTO() macros that were removed in 2.0b1 have been restored for
Jeremy Hylton1b618592000-09-26 05:32:36 +00003013 backwards compatibility (at the source level) with old extensions.
3014
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003015- A wrapper API was added for signal() and sigaction(). Instead of
3016 either function, always use PyOS_getsig() to get a signal handler
3017 and PyOS_setsig() to set one. A new convenience typedef
3018 PyOS_sighandler_t is defined for the type of signal handlers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00003019
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003020- Add PyString_AsStringAndSize() function that provides access to the
Jeremy Hylton1b618592000-09-26 05:32:36 +00003021 internal data buffer and size of a string object -- or the default
3022 encoded version of a Unicode object.
3023
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003024- PyString_Size() and PyString_AsString() accept Unicode objects.
3025
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003026- The standard header <limits.h> is now included by Python.h (if it
Fred Drake64bb3802000-09-26 16:21:35 +00003027 exists). INT_MAX and LONG_MAX will always be defined, even if
3028 <limits.h> is not available.
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003029
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003030- PyFloat_FromString takes a second argument, pend, that was
3031 effectively useless. It is now officially useless but preserved for
3032 backwards compatibility. If the pend argument is not NULL, *pend is
3033 set to NULL.
3034
3035- PyObject_GetAttr() and PyObject_SetAttr() now accept Unicode objects
3036 for the attribute name. See note on getattr() above.
3037
3038- A few bug fixes to argument processing for Unicode.
3039 PyArg_ParseTupleAndKeywords() now accepts "es#" and "es".
3040 PyArg_Parse() special cases "s#" for Unicode objects; it returns a
3041 pointer to the default encoded string data instead of to the raw
Tim Petersa3a3a032000-11-30 05:22:44 +00003042 UTF-16.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003043
3044- Py_BuildValue accepts B format (for bgen-generated code).
3045
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003046
Jeremy Hylton1b618592000-09-26 05:32:36 +00003047Internals
3048
3049- On Unix, fix code for finding Python installation directory so that
3050 it works when argv[0] is a relative path.
3051
Andrew M. Kuchlinga1099be2000-12-15 01:16:43 +00003052- Added a true unicode_internal_encode() function and fixed the
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003053 unicode_internal_decode function() to support Unicode objects directly
Jeremy Hylton1b618592000-09-26 05:32:36 +00003054 rather than by generating a copy of the object.
3055
Tim Peters482c0212000-09-26 06:33:09 +00003056- Several of the internal Unicode tables are much smaller now, and
3057 the source code should be much friendlier to weaker compilers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00003058
Jeremy Hylton97693b02000-09-26 17:42:51 +00003059- In the garbage collector: Fixed bug in collection of tuples. Fixed
3060 bug that caused some instances to be removed from the container set
3061 while they were still live. Fixed parsing in gc.set_debug() for
3062 platforms where sizeof(long) > sizeof(int).
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003063
3064- Fixed refcount problem in instance deallocation that only occurred
3065 when Py_REF_DEBUG was defined and Py_TRACE_REFS was not.
3066
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003067- On Windows, getpythonregpath is now protected against null data in
3068 registry key.
3069
3070- On Unix, create .pyc/.pyo files with O_EXCL flag to avoid a race
Tim Petersa3a3a032000-11-30 05:22:44 +00003071 condition.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003072
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003073
Jeremy Hylton1b618592000-09-26 05:32:36 +00003074Build and platform-specific issues
3075
3076- Better support of GNU Pth via --with-pth configure option.
3077
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003078- Python/C API now properly exposed to dynamically-loaded extension
3079 modules on Reliant UNIX.
Jeremy Hylton1b618592000-09-26 05:32:36 +00003080
3081- Changes for the benefit of SunOS 4.1.4 (really!). mmapmodule.c:
3082 Don't define MS_SYNC to be zero when it is undefined. Added missing
3083 prototypes in posixmodule.c.
3084
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003085- Improved support for HP-UX build. Threads should now be correctly
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003086 configured (on HP-UX 10.20 and 11.00).
Jeremy Hylton1b618592000-09-26 05:32:36 +00003087
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003088- Fix largefile support on older NetBSD systems and OpenBSD by adding
3089 define for TELL64.
3090
3091
3092Tools and other miscellany
3093
3094- ftpmirror: Call to main() is wrapped in if __name__ == "__main__".
3095
3096- freeze: The modulefinder now works with 2.0 opcodes.
3097
Tim Petersa3a3a032000-11-30 05:22:44 +00003098- IDLE:
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00003099 Move hackery of sys.argv until after the Tk instance has been
3100 created, which allows the application-specific Tkinter
3101 initialization to be executed if present; also pass an explicit
3102 className parameter to the Tk() constructor.
Fred Drake64bb3802000-09-26 16:21:35 +00003103
Jeremy Hylton1b618592000-09-26 05:32:36 +00003104
3105What's new in 2.0 beta 1?
3106=========================
3107
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003108Source Incompatibilities
3109------------------------
3110
3111None. Note that 1.6 introduced several incompatibilities with 1.5.2,
3112such as single-argument append(), connect() and bind(), and changes to
3113str(long) and repr(float).
3114
3115
3116Binary Incompatibilities
3117------------------------
3118
3119- Third party extensions built for Python 1.5.x or 1.6 cannot be used
3120with Python 2.0; these extensions will have to be rebuilt for Python
31212.0.
3122
3123- On Windows, attempting to import a third party extension built for
3124Python 1.5.x or 1.6 results in an immediate crash; there's not much we
3125can do about this. Check your PYTHONPATH environment variable!
3126
3127- Python bytecode files (*.pyc and *.pyo) are not compatible between
3128releases.
3129
3130
3131Overview of Changes Since 1.6
3132-----------------------------
3133
3134There are many new modules (including brand new XML support through
3135the xml package, and i18n support through the gettext module); a list
3136of all new modules is included below. Lots of bugs have been fixed.
3137
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003138The process for making major new changes to the language has changed
3139since Python 1.6. Enhancements must now be documented by a Python
3140Enhancement Proposal (PEP) before they can be accepted.
3141
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003142There are several important syntax enhancements, described in more
3143detail below:
3144
3145 - Augmented assignment, e.g. x += 1
3146
3147 - List comprehensions, e.g. [x**2 for x in range(10)]
3148
3149 - Extended import statement, e.g. import Module as Name
3150
3151 - Extended print statement, e.g. print >> file, "Hello"
3152
3153Other important changes:
3154
3155 - Optional collection of cyclical garbage
3156
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003157Python Enhancement Proposal (PEP)
3158---------------------------------
3159
3160PEP stands for Python Enhancement Proposal. A PEP is a design
3161document providing information to the Python community, or describing
3162a new feature for Python. The PEP should provide a concise technical
3163specification of the feature and a rationale for the feature.
3164
3165We intend PEPs to be the primary mechanisms for proposing new
3166features, for collecting community input on an issue, and for
3167documenting the design decisions that have gone into Python. The PEP
3168author is responsible for building consensus within the community and
3169documenting dissenting opinions.
3170
3171The PEPs are available at http://python.sourceforge.net/peps/.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003172
3173Augmented Assignment
3174--------------------
3175
3176This must have been the most-requested feature of the past years!
3177Eleven new assignment operators were added:
3178
Guido van Rossume905e952000-09-05 12:42:46 +00003179 += -= *= /= %= **= <<= >>= &= ^= |=
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003180
3181For example,
3182
3183 A += B
3184
3185is similar to
3186
3187 A = A + B
3188
3189except that A is evaluated only once (relevant when A is something
3190like dict[index].attr).
3191
3192However, if A is a mutable object, A may be modified in place. Thus,
3193if A is a number or a string, A += B has the same effect as A = A+B
3194(except A is only evaluated once); but if a is a list, A += B has the
3195same effect as A.extend(B)!
3196
3197Classes and built-in object types can override the new operators in
3198order to implement the in-place behavior; the not-in-place behavior is
3199used automatically as a fallback when an object doesn't implement the
3200in-place behavior. For classes, the method name is derived from the
3201method name for the corresponding not-in-place operator by inserting
3202an 'i' in front of the name, e.g. __iadd__ implements in-place
3203__add__.
3204
3205Augmented assignment was implemented by Thomas Wouters.
3206
3207
3208List Comprehensions
3209-------------------
3210
3211This is a flexible new notation for lists whose elements are computed
3212from another list (or lists). The simplest form is:
3213
3214 [<expression> for <variable> in <sequence>]
3215
Guido van Rossum56db0952000-09-06 23:34:25 +00003216For example, [i**2 for i in range(4)] yields the list [0, 1, 4, 9].
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003217This is more efficient than a for loop with a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003218
3219You can also add a condition:
3220
3221 [<expression> for <variable> in <sequence> if <condition>]
3222
3223For example, [w for w in words if w == w.lower()] would yield the list
3224of words that contain no uppercase characters. This is more efficient
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003225than a for loop with an if statement and a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003226
3227You can also have nested for loops and more than one 'if' clause. For
3228example, here's a function that flattens a sequence of sequences::
3229
3230 def flatten(seq):
3231 return [x for subseq in seq for x in subseq]
3232
3233 flatten([[0], [1,2,3], [4,5], [6,7,8,9], []])
3234
3235This prints
3236
3237 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
3238
3239List comprehensions originated as a patch set from Greg Ewing; Skip
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003240Montanaro and Thomas Wouters also contributed. Described by PEP 202.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003241
3242
3243Extended Import Statement
3244-------------------------
3245
3246Many people have asked for a way to import a module under a different
3247name. This can be accomplished like this:
3248
3249 import foo
3250 bar = foo
3251 del foo
3252
3253but this common idiom gets old quickly. A simple extension of the
3254import statement now allows this to be written as follows:
3255
3256 import foo as bar
3257
3258There's also a variant for 'from ... import':
3259
3260 from foo import bar as spam
3261
3262This also works with packages; e.g. you can write this:
3263
3264 import test.regrtest as regrtest
3265
3266Note that 'as' is not a new keyword -- it is recognized only in this
3267context (this is only possible because the syntax for the import
3268statement doesn't involve expressions).
3269
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003270Implemented by Thomas Wouters. Described by PEP 221.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003271
3272
3273Extended Print Statement
3274------------------------
3275
3276Easily the most controversial new feature, this extension to the print
3277statement adds an option to make the output go to a different file
3278than the default sys.stdout.
3279
3280For example, to write an error message to sys.stderr, you can now
3281write:
3282
3283 print >> sys.stderr, "Error: bad dog!"
3284
3285As a special feature, if the expression used to indicate the file
Fred Drake45888ff2000-09-29 17:09:11 +00003286evaluates to None, the current value of sys.stdout is used. Thus:
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003287
3288 print >> None, "Hello world"
3289
3290is equivalent to
3291
3292 print "Hello world"
3293
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003294Design and implementation by Barry Warsaw. Described by PEP 214.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003295
3296
3297Optional Collection of Cyclical Garbage
3298---------------------------------------
3299
3300Python is now equipped with a garbage collector that can hunt down
3301cyclical references between Python objects. It's no replacement for
3302reference counting; in fact, it depends on the reference counts being
3303correct, and decides that a set of objects belong to a cycle if all
3304their reference counts can be accounted for from their references to
3305each other. This devious scheme was first proposed by Eric Tiedemann,
3306and brought to implementation by Neil Schemenauer.
3307
3308There's a module "gc" that lets you control some parameters of the
3309garbage collection. There's also an option to the configure script
3310that lets you enable or disable the garbage collection. In 2.0b1,
3311it's on by default, so that we (hopefully) can collect decent user
3312experience with this new feature. There are some questions about its
Fred Drake9f11cf82000-09-29 17:54:40 +00003313performance. If it proves to be too much of a problem, we'll turn it
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003314off by default in the final 2.0 release.
3315
3316
3317Smaller Changes
3318---------------
3319
3320A new function zip() was added. zip(seq1, seq2, ...) is equivalent to
3321map(None, seq1, seq2, ...) when the sequences have the same length;
3322i.e. zip([1,2,3], [10,20,30]) returns [(1,10), (2,20), (3,30)]. When
3323the lists are not all the same length, the shortest list wins:
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003324zip([1,2,3], [10,20]) returns [(1,10), (2,20)]. See PEP 201.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003325
3326sys.version_info is a tuple (major, minor, micro, level, serial).
3327
3328Dictionaries have an odd new method, setdefault(key, default).
3329dict.setdefault(key, default) returns dict[key] if it exists; if not,
3330it sets dict[key] to default and returns that value. Thus:
3331
3332 dict.setdefault(key, []).append(item)
3333
3334does the same work as this common idiom:
3335
3336 if not dict.has_key(key):
3337 dict[key] = []
3338 dict[key].append(item)
3339
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003340There are two new variants of SyntaxError that are raised for
3341indentation-related errors: IndentationError and TabError.
3342
3343Changed \x to consume exactly two hex digits; see PEP 223. Added \U
3344escape that consumes exactly eight hex digits.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003345
3346The limits on the size of expressions and file in Python source code
3347have been raised from 2**16 to 2**32. Previous versions of Python
3348were limited because the maximum argument size the Python VM accepted
3349was 2**16. This limited the size of object constructor expressions,
3350e.g. [1,2,3] or {'a':1, 'b':2}, and the size of source files. This
3351limit was raised thanks to a patch by Charles Waldman that effectively
3352fixes the problem. It is now much more likely that you will be
3353limited by available memory than by an arbitrary limit in Python.
3354
3355The interpreter's maximum recursion depth can be modified by Python
3356programs using sys.getrecursionlimit and sys.setrecursionlimit. This
3357limit is the maximum number of recursive calls that can be made by
3358Python code. The limit exists to prevent infinite recursion from
3359overflowing the C stack and causing a core dump. The default value is
33601000. The maximum safe value for a particular platform can be found
3361by running Misc/find_recursionlimit.py.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003362
3363New Modules and Packages
3364------------------------
3365
3366atexit - for registering functions to be called when Python exits.
3367
3368imputil - Greg Stein's alternative API for writing custom import
3369hooks.
3370
3371pyexpat - an interface to the Expat XML parser, contributed by Paul
3372Prescod.
3373
3374xml - a new package with XML support code organized (so far) in three
3375subpackages: xml.dom, xml.sax, and xml.parsers. Describing these
3376would fill a volume. There's a special feature whereby a
3377user-installed package named _xmlplus overrides the standard
3378xmlpackage; this is intended to give the XML SIG a hook to distribute
3379backwards-compatible updates to the standard xml package.
3380
3381webbrowser - a platform-independent API to launch a web browser.
3382
3383
Guido van Rossume905e952000-09-05 12:42:46 +00003384Changed Modules
3385---------------
3386
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003387array -- new methods for array objects: count, extend, index, pop, and
3388remove
3389
3390binascii -- new functions b2a_hex and a2b_hex that convert between
3391binary data and its hex representation
3392
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003393calendar -- Many new functions that support features including control
3394over which day of the week is the first day, returning strings instead
3395of printing them. Also new symbolic constants for days of week,
3396e.g. MONDAY, ..., SUNDAY.
3397
3398cgi -- FieldStorage objects have a getvalue method that works like a
3399dictionary's get method and returns the value attribute of the object.
3400
3401ConfigParser -- The parser object has new methods has_option,
3402remove_section, remove_option, set, and write. They allow the module
3403to be used for writing config files as well as reading them.
3404
3405ftplib -- ntransfercmd(), transfercmd(), and retrbinary() all now
Guido van Rossume905e952000-09-05 12:42:46 +00003406optionally support the RFC 959 REST command.
3407
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003408gzip -- readline and readlines now accept optional size arguments
Guido van Rossume905e952000-09-05 12:42:46 +00003409
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003410httplib -- New interfaces and support for HTTP/1.1 by Greg Stein. See
3411the module doc strings for details.
Guido van Rossum830ca2a2000-09-05 15:34:16 +00003412
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003413locale -- implement getdefaultlocale for Win32 and Macintosh
3414
3415marshal -- no longer dumps core when marshaling deeply nested or
3416recursive data structures
3417
3418os -- new functions isatty, seteuid, setegid, setreuid, setregid
3419
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003420os/popen2 -- popen2/popen3/popen4 support under Windows. popen2/popen3
3421support under Unix.
3422
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003423os/pty -- support for openpty and forkpty
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003424
3425os.path -- fix semantics of os.path.commonprefix
3426
3427smtplib -- support for sending very long messages
3428
3429socket -- new function getfqdn()
3430
3431readline -- new functions to read, write and truncate history files.
3432The readline section of the library reference manual contains an
3433example.
3434
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003435select -- add interface to poll system call
3436
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003437shutil -- new copyfileobj function
3438
3439SimpleHTTPServer, CGIHTTPServer -- Fix problems with buffering in the
3440HTTP server.
3441
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003442Tkinter -- optimization of function flatten
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003443
3444urllib -- scans environment variables for proxy configuration,
Tim Peters8b092332000-09-05 20:15:25 +00003445e.g. http_proxy.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003446
3447whichdb -- recognizes dumbdbm format
Guido van Rossume905e952000-09-05 12:42:46 +00003448
3449
3450Obsolete Modules
3451----------------
3452
3453None. However note that 1.6 made a whole slew of modules obsolete:
3454stdwin, soundex, cml, cmpcache, dircache, dump, find, grep, packmail,
3455poly, zmod, strop, util, whatsound.
3456
3457
3458Changed, New, Obsolete Tools
3459----------------------------
3460
Tim Peters8b092332000-09-05 20:15:25 +00003461None.
Guido van Rossume905e952000-09-05 12:42:46 +00003462
3463
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003464C-level Changes
3465---------------
3466
3467Several cleanup jobs were carried out throughout the source code.
3468
3469All C code was converted to ANSI C; we got rid of all uses of the
3470Py_PROTO() macro, which makes the header files a lot more readable.
3471
3472Most of the portability hacks were moved to a new header file,
3473pyport.h; several other new header files were added and some old
3474header files were removed, in an attempt to create a more rational set
3475of header files. (Few of these ever need to be included explicitly;
3476they are all included by Python.h.)
3477
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003478Trent Mick ensured portability to 64-bit platforms, under both Linux
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003479and Win64, especially for the new Intel Itanium processor. Mick also
3480added large file support for Linux64 and Win64.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00003481
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003482The C APIs to return an object's size have been update to consistently
3483use the form PyXXX_Size, e.g. PySequence_Size and PyDict_Size. In
3484previous versions, the abstract interfaces used PyXXX_Length and the
3485concrete interfaces used PyXXX_Size. The old names,
3486e.g. PyObject_Length, are still available for backwards compatibility
3487at the API level, but are deprecated.
3488
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003489The PyOS_CheckStack function has been implemented on Windows by
3490Fredrik Lundh. It prevents Python from failing with a stack overflow
3491on Windows.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003492
3493The GC changes resulted in creation of two new slots on object,
3494tp_traverse and tp_clear. The augmented assignment changes result in
Guido van Rossum4338a282000-09-06 13:02:08 +00003495the creation of a new slot for each in-place operator.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003496
3497The GC API creates new requirements for container types implemented in
Guido van Rossum4338a282000-09-06 13:02:08 +00003498C extension modules. See Include/objimpl.h for details.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003499
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003500PyErr_Format has been updated to automatically calculate the size of
3501the buffer needed to hold the formatted result string. This change
3502prevents crashes caused by programmer error.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00003503
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003504New C API calls: PyObject_AsFileDescriptor, PyErr_WriteUnraisable.
Guido van Rossume905e952000-09-05 12:42:46 +00003505
Jeremy Hylton24c3d602000-09-05 19:36:26 +00003506PyRun_AnyFileEx, PyRun_SimpleFileEx, PyRun_FileEx -- New functions
3507that are the same as their non-Ex counterparts except they take an
3508extra flag argument that tells them to close the file when done.
3509
3510XXX There were other API changes that should be fleshed out here.
Guido van Rossumab9d6f01998-08-10 22:01:13 +00003511
Tim Peters8b092332000-09-05 20:15:25 +00003512
3513Windows Changes
3514---------------
3515
3516New popen2/popen3/peopen4 in os module (see Changed Modules above).
3517
3518os.popen is much more usable on Windows 95 and 98. See Microsoft
3519Knowledge Base article Q150956. The Win9x workaround described there
3520is implemented by the new w9xpopen.exe helper in the root of your
3521Python installation. Note that Python uses this internally; it is not
3522a standalone program.
3523
3524Administrator privileges are no longer required to install Python
3525on Windows NT or Windows 2000. If you have administrator privileges,
3526Python's registry info will be written under HKEY_LOCAL_MACHINE.
3527Otherwise the installer backs off to writing Python's registry info
Guido van Rossum4338a282000-09-06 13:02:08 +00003528under HKEY_CURRENT_USER. The latter is sufficient for all "normal"
Tim Peters8b092332000-09-05 20:15:25 +00003529uses of Python, but will prevent some advanced uses from working
3530(for example, running a Python script as an NT service, or possibly
3531from CGI).
3532
3533[This was new in 1.6] The installer no longer runs a separate Tcl/Tk
3534installer; instead, it installs the needed Tcl/Tk files directly in the
3535Python directory. If you already have a Tcl/Tk installation, this
3536wastes some disk space (about 4 Megs) but avoids problems with
3537conflicting Tcl/Tk installations, and makes it much easier for Python
3538to ensure that Tcl/Tk can find all its files.
3539
3540[This was new in 1.6] The Windows installer now installs by default in
3541\Python20\ on the default volume, instead of \Program Files\Python-2.0\.
3542
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00003543
3544Updates to the changes between 1.5.2 and 1.6
3545--------------------------------------------
3546
3547The 1.6 NEWS file can't be changed after the release is done, so here
3548is some late-breaking news:
3549
3550New APIs in locale.py: normalize(), getdefaultlocale(), resetlocale(),
3551and changes to getlocale() and setlocale().
3552
3553The new module is now enabled per default.
3554
3555It is not true that the encodings codecs cannot be used for normal
3556strings: the string.encode() (which is also present on 8-bit strings
3557!) allows using them for 8-bit strings too, e.g. to convert files from
3558cp1252 (Windows) to latin-1 or vice-versa.
3559
3560Japanese codecs are available from Tamito KAJIYAMA:
3561http://pseudo.grad.sccs.chukyo-u.ac.jp/~kajiyama/python/
3562
3563
Guido van Rossumab9d6f01998-08-10 22:01:13 +00003564======================================================================