blob: 987340190a4fd08314896d651d52a8e992066be6 [file] [log] [blame]
Tim Peters20f51a72001-07-21 02:31:40 +00001What's New in Python 2.2a2?
2===========================
3
4Tests
5
6- Several new tests in the standard test suite, with special thanks to
7 Nick Mathewson.
8
9Core
10
11Library
12
13New platforms
14
15C API
16
17
Guido van Rossum55a78992001-07-17 17:22:32 +000018What's New in Python 2.2a1?
Tim Petersf553f892001-05-01 20:45:31 +000019===========================
20
21Core
Tim Petersa814db52001-05-14 07:05:58 +000022
Guido van Rossum55a78992001-07-17 17:22:32 +000023- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +000024 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +000025 more 'yield' statements. See PEP 255. Since this adds a new
26 keyword to the language, this feature must be enabled by including a
27 future statement: "from __future__ import generators" (see PEP 236).
28 Generators will become a standard feature in a future release
29 (probably 2.3). Without this future statement, 'yield' remains an
30 ordinary identifier, but a warning is issued each time it is used.
31 (These warnings currently don't conform to the warnings framework of
32 PEP 230; we intend to fix this in 2.2a2.)
33
Marc-André Lemburg12e74b32001-05-22 08:58:23 +000034- The UTF-16 codec was modified to be more RFC compliant. It will now
35 only remove BOM characters at the start of the string and then
36 only if running in native mode (UTF-16-LE and -BE won't remove a
37 leading BMO character).
38
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +000039- Strings now have a new method .decode() to complement the already
40 existing .encode() method. These two methods provide direct access
41 to the corresponding decoders and encoders of the registered codecs.
42
43 To enhance the usability of the .encode() method, the special
44 casing of Unicode object return values was dropped (Unicode objects
45 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +000046
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +000047 Both methods will now return whatever the codec in charge of the
48 requested encoding returns as object, e.g. Unicode codecs will
49 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
50 will return u"äöü"). This enables codec writer to create codecs
51 for various simple to use conversions.
52
53 New codecs were added to demonstrate these new features (the .encode()
54 and .decode() columns indicate the type of the returned objects):
55
56 Name | .encode() | .decode() | Description
57 ----------------------------------------------------------------------
58 uu | string | string | UU codec (e.g. for email)
59 base64 | string | string | base64 codec
Guido van Rossumc3415802001-06-06 13:30:54 +000060 quopri | string | string | quoted-printable codec
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +000061 zlib | string | string | zlib compression
62 hex | string | string | 2-byte hex codec
63 rot-13 | string | Unicode | ROT-13 Unicode charmap codec
64
Mark Hammond2a0af792001-05-14 03:09:36 +000065- Some operating systems now support the concept of a default Unicode
66 encoding for file system operations. Notably, Windows supports 'mbcs'
67 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +000068 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +000069 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +000070
71 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +000072 functions that return filenames (such as os.listdir()) to return Python
73 string objects pre-encoded using the default file system encoding for
74 the platform. As this encoding is likely to be different from Python's
75 default encoding, converting this name to a Unicode object before passing
76 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +000077 would attempt to use its default encoding (generally ASCII) rather than
78 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +000079
Tim Petersa814db52001-05-14 07:05:58 +000080 In general, this change simply removes surprises when working with
81 Unicode and the file system, making these operations work as you expect,
82 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +000083 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +000084
Tim Peters61dff2b2001-05-08 15:43:37 +000085- Float (and complex) literals in source code were evaluated to full
86 precision only when running from a .py file; the same code loaded from a
87 .pyc (or .pyo) file could suffer numeric differences starting at about the
88 12th significant decimal digit. For example, on a machine with IEEE-754
89 floating arithmetic,
90
91 x = 9007199254740992.0
92 print long(x)
93
94 printed 9007199254740992 if run directly from .py, but 9007199254740000
95 if from a compiled (.pyc or .pyo) file. This was due to marshal using
96 str(float) instead of repr(float) when building code objects. marshal
97 now uses repr(float) instead, which should reproduce floats to full
98 machine precision (assuming the platform C float<->string I/O conversion
99 functions are of good quality).
100
101 This may cause floating-point results to change in some cases, and
102 usually for the better, but may also cause numerically unstable
103 algorithms to break.
104
Tim Peters2f228e72001-05-13 00:19:31 +0000105- The implementation of dicts suffers fewer collisions, which has speed
106 benefits. However, the order in which dict entries appear in dict.keys(),
107 dict.values() and dict.items() may differ from previous releases for a
108 given dict. Nothing is defined about this order, so no program should
109 rely on it. Nevertheless, it's easy to write test cases that rely on the
110 order by accident, typically because of printing the str() or repr() of a
111 dict to an "expected results" file. See Lib/test/test_support.py's new
112 sortdict(dict) function for a simple way to display a dict in sorted
113 order.
114
Tim Peters7a3bfc32001-06-12 01:22:22 +0000115- Many other small changes to dicts were made, resulting in faster
116 operation along the most common code paths.
117
Guido van Rossum10315822001-05-01 20:54:30 +0000118- Dictionary objects now support the "in" operator: "x in dict" means
119 the same as dict.has_key(x).
120
Barry Warsaw51acc8d2001-06-26 20:12:50 +0000121- The update() method of dictionaries now accepts generic mapping
122 objects. Specifically the argument object must support the .keys()
123 and __getitem__() methods. This allows you to say, for example,
124 {}.update(UserDict())
125
Guido van Rossum10315822001-05-01 20:54:30 +0000126- Iterators were added; this is a generalized way of providing values
127 to a for loop. See PEP 234. There's a new built-in function iter()
128 to return an iterator. There's a new protocol to get the next value
129 from an iterator using the next() method (in Python) or the
130 tp_iternext slot (in C). There's a new protocol to get iterators
131 using the __iter__() method (in Python) or the tp_iter slot (in C).
132 Iterating (i.e. a for loop) over a dictionary generates its keys.
133 Iterating over a file generates its lines.
134
Tim Petersf553f892001-05-01 20:45:31 +0000135- The following functions were generalized to work nicely with iterator
136 arguments:
Tim Peterse63415e2001-05-08 04:38:29 +0000137 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +0000138 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
139 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +0000140 join() method of strings
141 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +0000142 'x in y' and 'x not in y' (PySequence_Contains() in C API)
143 operator.countOf() (PySequence_Count() in C API)
Tim Petersd6d010b2001-06-21 02:49:55 +0000144 right-hand side of assignment statements with multiple targets, such as
145 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +0000146
Tim Petersd85e1022001-05-11 21:51:48 +0000147- Accessing module attributes is significantly faster (for example,
148 random.random or os.path or yourPythonModule.yourAttribute).
149
Tim Peterse63415e2001-05-08 04:38:29 +0000150- Comparing dictionary objects via == and != is faster, and now works even
151 if the keys and values don't support comparisons other than ==.
152
Tim Peters95bf9392001-05-10 08:32:44 +0000153- Comparing dictionaries in ways other than == and != is slower: there were
154 insecurities in the dict comparison implementation that could cause Python
155 to crash if the element comparison routines for the dict keys and/or
156 values mutated the dicts. Making the code bulletproof slowed it down.
157
Tim Peterseb28ef22001-06-02 05:27:19 +0000158- Collisions in dicts are resolved via a new approach, which can help
159 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +0000160 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +0000161 faster now. Thanks to Christian Tismer for pointing out the cause and
162 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +0000163
Tim Peters52e155e2001-06-16 05:42:57 +0000164- repr() is much faster for large containers (dict, list, tuple).
165
166
Tim Petersa814db52001-05-14 07:05:58 +0000167Library
168
Fred Drake960fdf92001-07-20 18:38:26 +0000169- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
170 were added to the string module. These a locale-indenpendent
171 constants, unlike letters, lowercase, and uppercase. These are now
172 use in appropriate locations in the standard library.
173
Martin v. Löwisf0473d52001-07-18 16:17:16 +0000174- The flags used in dlopen calls can now be configured using
175 sys.setdlopenflags and queried using sys.getdlopenflags.
176
Guido van Rossumc7e4aca2001-07-12 11:54:37 +0000177- Fredrik Lundh's xmlrpclib is now a standard library module. This
178 provides full client-side XML-RPC support. In addition,
179 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
180 one asyncore-based). Thanks to Eric Raymond for the documentation.
181
Guido van Rossum643d3912001-07-05 14:46:25 +0000182- The xrange() object is simplified: it no longer supports slicing,
183 repetition, comparisons, efficient 'in' checking, the tolist()
184 method, or the start, stop and step attributes. See PEP 260.
185
Martin v. Löwisebf94db2001-06-06 06:25:40 +0000186- A new function fnmatch.filter to filter lists of file names was added.
187
Barry Warsawffd674d2001-05-22 16:00:10 +0000188- calendar.py uses month and day names based on the current locale.
189
Guido van Rossum2e0a6542001-05-15 02:14:44 +0000190- strop is now *really* obsolete (this was announced before with 1.6),
191 and issues DeprecationWarning when used (except for the four items
192 that are still imported into string.py).
193
Tim Petersa814db52001-05-14 07:05:58 +0000194- Cookie.py now sorts key+value pairs by key in output strings.
195
196- pprint.isrecursive(object) didn't correctly identify recursive objects.
197 Now it does.
198
Tim Peters95b3f782001-05-14 18:39:41 +0000199- pprint functions now much faster for large containers (tuple, list, dict).
200
Tim Peters7b9542a2001-06-10 23:40:19 +0000201- New 'q' and 'Q' format codes in the struct module, corresponding to C
202 types "long long" and "unsigned long long" (on Windows, __int64). In
203 native mode, these can be used only when the platform C compiler supports
204 these types (when HAVE_LONG_LONG is #define'd by the Python config
205 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +0000206 In standard mode, 'q' and 'Q' are supported on all platforms, and are
207 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +0000208
Guido van Rossum83213cc2001-06-12 16:48:52 +0000209- The site module installs a new built-in function 'help' that invokes
210 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
211 it displays a message reminding the user to use 'help()' or
212 'help(object)'.
213
Tim Petersa814db52001-05-14 07:05:58 +0000214Tests
215
216- New test_mutants.py runs dict comparisons where the key and value
217 comparison operators mutute the dicts randomly during comparison. This
218 rapidly causes Python to crash under earlier releases (not for the faint
219 of heart: it can also cause Win9x to freeze or reboot!).
220
221- New test_pprint.py verfies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +0000222 pprint.isreadable() return sensible results. Also verifies that simple
223 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +0000224
Tim Peters58e0a8c2001-05-14 22:32:33 +0000225New platforms
226
227- Python should compile and run out of the box using the Borland C
228 compiler (under Windows), thanks to Stephen Hansen.
Tim Petersf553f892001-05-01 20:45:31 +0000229
Tim Peters4324aa32001-05-28 22:30:08 +0000230C API
231
232- Removed the unused last_is_sticky argument from the internal
233 _PyTuple_Resize(). If this affects you, you were cheating.
234
235
Guido van Rossum55a78992001-07-17 17:22:32 +0000236======================================================================
237
238
Guido van Rossumffe13be2001-04-16 18:46:45 +0000239What's New in Python 2.1 (final)?
240=================================
241
242We only changed a few things since the last release candidate, all in
243Python library code:
244
245- A bug in the locale module was fixed that affected locales which
246 define no grouping for numeric formatting.
247
248- A few bugs in the weakref module's implementations of weak
249 dictionaries (WeakValueDictionary and WeakKeyDictionary) were fixed,
250 and the test suite was updated to check for these bugs.
251
252- An old bug in the os.path.walk() function (introduced in Python
253 2.0!) was fixed: a non-existent file would cause an exception
254 instead of being ignored.
255
256- Fixed a few bugs in the new symtable module found by Neil Norwitz's
257 PyChecker.
258
259
Guido van Rossum5b08f132001-04-16 02:05:23 +0000260What's New in Python 2.1c2?
261===========================
Barry Warsaw11e89c72001-04-11 20:37:57 +0000262
Guido van Rossum5b08f132001-04-16 02:05:23 +0000263A flurry of small changes, and one showstopper fixed in the nick of
264time made it necessary to release another release candidate. The list
265here is the *complete* list of patches (except version updates):
Guido van Rossum4fb60362001-04-13 00:46:14 +0000266
Guido van Rossum5b08f132001-04-16 02:05:23 +0000267Core
Guido van Rossum4fb60362001-04-13 00:46:14 +0000268
Guido van Rossum5b08f132001-04-16 02:05:23 +0000269- Tim discovered a nasty bug in the dictionary code, caused by
270 PyDict_Next() calling dict_resize(), and the GC code's use of
271 PyDict_Next() violating an assumption in dict_items(). This was
272 fixed with considerable amounts of band-aid, but the net effect is a
273 saner and more robust implementation.
274
275- Made a bunch of symbols static that were accidentally global.
276
277Build and Ports
278
279- The setup.py script didn't check for a new enough version of zlib
280 (1.1.3 is needed). Now it does.
281
282- Changed "make clean" target to also remove shared libraries.
283
284- Added a more general warning about the SGI Irix optimizer to README.
285
286Library
287
288- Fix a bug in urllib.basejoin("http://host", "../file.html") which
289 omitted the slash between host and file.html.
290
291- The mailbox module's _Mailbox class contained a completely broken
292 and undocumented seek() method. Ripped it out.
293
294- Fixed a bunch of typos in various library modules (urllib2, smtpd,
295 sgmllib, netrc, chunk) found by Neil Norwitz's PyChecker.
296
297- Fixed a few last-minute bugs in unittest.
298
299Extensions
300
301- Reverted the patch to the OpenSSL code in socketmodule.c to support
302 RAND_status() and the EGD, and the subsequent patch that tried to
303 fix it for pre-0.9.5 versions; the problem with the patch is that on
304 some systems it issues a warning whenever socket is imported, and
305 that's unacceptable.
306
307Tests
308
309- Fixed the pickle tests to work with "import test.test_pickle".
310
311- Tweaked test_locale.py to actually run the test Windows.
312
313- In distutils/archive_util.py, call zipfile.ZipFile() with mode "w",
314 not "wb" (which is not a valid mode at all).
315
316- Fix pstats browser crashes. Import readline if it exists to make
317 the user interface nicer.
318
319- Add "import thread" to the top of test modules that import the
320 threading module (test_asynchat and test_threadedtempfile). This
321 prevents test failures caused by a broken threading module resulting
322 from a previously caught failed import.
323
324- Changed test_asynchat.py to set the SO_REUSEADDR option; this was
325 needed on some platforms (e.g. Solaris 8) when the tests are run
326 twice in succession.
327
328- Skip rather than fail test_sunaudiodev if no audio device is found.
329
330
331What's New in Python 2.1c1?
332===========================
333
334This list was significantly updated when 2.1c2 was released; the 2.1c1
335release didn't mention most changes that were actually part of 2.1c1:
336
337Legal
338
339- Copyright was assigned to the Python Software Foundation (PSF) and a
340 PSF license (very similar to the CNRI license) was added.
341
342- The CNRI copyright notice was updated to include 2001.
343
344Core
Barry Warsaw11e89c72001-04-11 20:37:57 +0000345
Guido van Rossumc9932722001-04-12 02:31:27 +0000346- After a public outcry, assignment to __debug__ is no longer illegal;
347 instead, a warning is issued. It will become illegal in 2.2.
348
Guido van Rossum5b08f132001-04-16 02:05:23 +0000349- Fixed a core dump with "%#x" % 0, and changed the semantics so that
350 "%#x" now always prepends "0x", even if the value is zero.
351
352- Fixed some nits in the bytecode compiler.
353
354- Fixed core dumps when calling certain kinds of non-functions.
355
356- Fixed various core dumps caused by reference count bugs.
357
358Build and Ports
359
360- Use INSTALL_SCRIPT to install script files.
361
Guido van Rossum34d37dc2001-04-11 21:03:32 +0000362- New port: SCO Unixware 7, by Billy G. Allie.
363
Guido van Rossum5b08f132001-04-16 02:05:23 +0000364- Updated RISCOS port.
365
366- Updated BeOS port and notes.
367
368- Various other porting problems resolved.
369
370Library
371
372- The TERMIOS and SOCKET modules are now truly obsolete and
373 unnecessary. Their symbols are incorporated in the termios and
374 socket modules.
375
376- Fixed some 64-bit bugs in pickle, cPickle, and struct, and added
377 better tests for pickling.
378
379- threading: make Condition.wait() robust against KeyboardInterrupt.
380
381- zipfile: add support to zipfile to support opening an archive
382 represented by an open file rather than a file name. Fix bug where
383 the archive was not properly closed. Fixed a bug in this bugfix
384 where flush() was called for a read-only file.
385
386- imputil: added an uninstall() method to the ImportManager.
387
388- Canvas: fixed bugs in lower() and tkraise() methods.
389
390- SocketServer: API change (added overridable close_request() method)
391 so that the TCP server can explicitly close the request.
392
393- pstats: Eric Raymond added a simple interactive statistics browser,
394 invoked when the module is run as a script.
395
396- locale: fixed a problem in format().
397
398- webbrowser: made it work when the BROWSER environment variable has a
399 value like "/usr/bin/netscape". Made it auto-detect Konqueror for
400 KDE 2. Fixed some other nits.
401
402- unittest: changes to allow using a different exception than
403 AssertionError, and added a few more function aliases. Some other
404 small changes.
405
406- urllib, urllib2: fixed redirect problems and a coupleof other nits.
407
408- asynchat: fixed a critical bug in asynchat that slipped through the
409 2.1b2 release. Fixed another rare bug.
410
411- Fix some unqualified except: clauses (always a bad code example).
412
413XML
414
415- pyexpat: new API get_version_string().
416
417- Fixed some minidom bugs.
418
419Extensions
420
421- Fixed a core dump in _weakref. Removed the weakref.mapping()
422 function (it adds nothing to the API).
423
424- Rationalized the use of header files in the readline module, to make
425 it compile (albeit with some warnings) with the very recent readline
426 4.2, without breaking for earlier versions.
427
428- Hopefully fixed a buffering problem in linuxaudiodev.
429
430- Attempted a fix to make the OpenSSL support in the socket module
431 work again with pre-0.9.5 versions of OpenSSL.
432
433Tests
434
435- Added a test case for asynchat and asyncore.
436
437- Removed coupling between tests where one test failing could break
438 another.
439
440Tools
441
442- Ping added an interactive help browser to pydoc, fixed some nits
443 in the rest of the pydoc code, and added some features to his
444 inspect module.
445
446- An updated python-mode.el version 4.1 which integrates Ken
447 Manheimer's pdbtrack.el. This makes debugging Python code via pdb
448 much nicer in XEmacs and Emacs. When stepping through your program
449 with pdb, in either the shell window or the *Python* window, the
450 source file and line will be tracked by an arrow. Very cool!
451
452- IDLE: syntax warnings in interactive mode are changed into errors.
453
454- Some improvements to Tools/webchecker (ignore some more URL types,
Tim Peters0e57abf2001-05-02 07:39:38 +0000455 follow some more links).
Guido van Rossum5b08f132001-04-16 02:05:23 +0000456
457- Brought the Tools/compiler package up to date.
Guido van Rossum34d37dc2001-04-11 21:03:32 +0000458
Barry Warsaw11e89c72001-04-11 20:37:57 +0000459
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000460What's New in Python 2.1 beta 2?
461================================
462
Guido van Rossum053ae352001-03-22 14:17:21 +0000463(Unlisted are many fixed bugs, more documentation, etc.)
464
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000465Core language, builtins, and interpreter
466
Guido van Rossum053ae352001-03-22 14:17:21 +0000467- The nested scopes work (enabled by "from __future__ import
468 nested_scopes") is completed; in particular, the future now extends
469 into code executed through exec, eval() and execfile(), and into the
470 interactive interpreter.
471
472- When calling a base class method (e.g. BaseClass.__init__(self)),
473 this is now allowed even if self is not strictly spoken a class
474 instance (e.g. when using metaclasses or the Don Beaudry hook).
475
476- Slice objects are now comparable but not hashable; this prevents
477 dict[:] from being accepted but meaningless.
478
479- Complex division is now calculated using less braindead algorithms.
480 This doesn't change semantics except it's more likely to give useful
481 results in extreme cases. Complex repr() now uses full precision
482 like float repr().
483
484- sgmllib.py now calls handle_decl() for simple <!...> declarations.
485
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000486- It is illegal to assign to the name __debug__, which is set when the
487 interpreter starts. It is effectively a compile-time constant.
488
489- A warning will be issued if a global statement for a variable
490 follows a use or assignment of that variable.
491
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000492Standard library
493
Guido van Rossum053ae352001-03-22 14:17:21 +0000494- unittest.py, a unit testing framework by Steve Purcell (PyUNIT,
495 inspired by JUnit), is now part of the standard library. You now
496 have a choice of two testing frameworks: unittest requires you to
497 write testcases as separate code, doctest gathers them from
498 docstrings. Both approaches have their advantages and
499 disadvantages.
500
501- A new module Tix was added, which wraps the Tix extension library
502 for Tk. With that module, it is not necessary to statically link
503 Tix with _tkinter, since Tix will be loaded with Tcl's "package
504 require" command. See Demo/tix/.
505
506- tzparse.py is now obsolete.
507
508- In gzip.py, the seek() and tell() methods are removed -- they were
509 non-functional anyway, and it's better if callers can test for their
510 existence with hasattr().
511
512Python/C API
513
514- PyDict_Next(): it is now safe to call PyDict_SetItem() with a key
515 that's already in the dictionary during a PyDict_Next() iteration.
516 This used to fail occasionally when a dictionary resize operation
517 could be triggered that would rehash all the keys. All other
518 modifications to the dictionary are still off-limits during a
519 PyDict_Next() iteration!
520
521- New extended APIs related to passing compiler variables around.
522
523- New abstract APIs PyObject_IsInstance(), PyObject_IsSubclass()
524 implement isinstance() and issubclass().
525
526- Py_BuildValue() now has a "D" conversion to create a Python complex
527 number from a Py_complex C value.
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000528
Fred Drake4e262a92001-03-22 18:26:47 +0000529- Extensions types which support weak references must now set the
530 field allocated for the weak reference machinery to NULL themselves;
531 this is done to avoid the cost of checking each object for having a
532 weakly referencable type in PyObject_INIT(), since most types are
533 not weakly referencable.
534
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000535- PyFrame_FastToLocals() and PyFrame_LocalsToFast() copy bindings for
536 free variables and cell variables to and from the frame's f_locals.
537
538- Variants of several functions defined in pythonrun.h have been added
539 to support the nested_scopes future statement. The variants all end
540 in Flags and take an extra argument, a PyCompilerFlags *; examples:
541 PyRun_AnyFileExFlags(), PyRun_InteractiveLoopFlags(). These
542 variants may be removed in Python 2.2, when nested scopes are
Tim Peters0e57abf2001-05-02 07:39:38 +0000543 mandatory.
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000544
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000545Distutils
546
547- the sdist command now writes a PKG-INFO file, as described in PEP 241,
548 into the release tree.
549
Tim Peters0e57abf2001-05-02 07:39:38 +0000550- several enhancements to the bdist_wininst command from Thomas Heller
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000551 (an uninstaller, more customization of the installer's display)
552
553- from Jack Jansen: added Mac-specific code to generate a dialog for
554 users to specify the command-line (because providing a command-line with
Tim Peters0e57abf2001-05-02 07:39:38 +0000555 MacPython is awkward). Jack also made various fixes for the Mac
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000556 and the Metrowerks compiler.
Tim Peters0e57abf2001-05-02 07:39:38 +0000557
558- added 'platforms' and 'keywords' to the set of metadata that can be
559 specified for a distribution.
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000560
561- applied patches from Jason Tishler to make the compiler class work with
562 Cygwin.
563
564
Tim Peters2fe289a2001-03-01 22:19:38 +0000565What's New in Python 2.1 beta 1?
566================================
Tim Petersd66595f2001-02-04 03:09:53 +0000567
568Core language, builtins, and interpreter
569
Guido van Rossum9d0fbde2001-03-02 14:00:32 +0000570- Following an outcry from the community about the amount of code
571 broken by the nested scopes feature introduced in 2.1a2, we decided
572 to make this feature optional, and to wait until Python 2.2 (or at
573 least 6 months) to make it standard. The option can be enabled on a
574 per-module basis by adding "from __future__ import nested_scopes" at
575 the beginning of a module (before any other statements, but after
576 comments and an optional docstring). See PEP 236 (Back to the
577 __future__) for a description of the __future__ statement. PEP 227
578 (Statically Nested Scopes) has been updated to reflect this change,
579 and to clarify the semantics in a number of endcases.
580
581- The nested scopes code, when enabled, has been hardened, and most
582 bugs and memory leaks in it have been fixed.
583
584- Compile-time warnings are now generated for a number of conditions
585 that will break or change in meaning when nested scopes are enabled:
586
587 - Using "from...import *" or "exec" without in-clause in a function
588 scope that also defines a lambda or nested function with one or
589 more free (non-local) variables. The presence of the import* or
590 bare exec makes it impossible for the compiler to determine the
591 exact set of local variables in the outer scope, which makes it
592 impossible to determine the bindings for free variables in the
593 inner scope. To avoid the warning about import *, change it into
594 an import of explicitly name object, or move the import* statement
595 to the global scope; to avoid the warning about bare exec, use
596 exec...in... (a good idea anyway -- there's a possibility that
597 bare exec will be deprecated in the future).
598
599 - Use of a global variable in a nested scope with the same name as a
600 local variable in a surrounding scope. This will change in
601 meaning with nested scopes: the name in the inner scope will
602 reference the variable in the outer scope rather than the global
603 of the same name. To avoid the warning, either rename the outer
604 variable, or use a global statement in the inner function.
605
Neil Schemenauera35c6882001-02-27 04:45:05 +0000606- An optional object allocator has been included. This allocator is
607 optimized for Python objects and should be faster and use less memory
608 than the standard system allocator. It is not enabled by default
609 because of possible thread safety problems. The allocator is only
610 protected by the Python interpreter lock and it is possible that some
611 extension modules require a thread safe allocator. The object
612 allocator can be enabled by providing the "--with-pymalloc" option to
613 configure.
614
Tim Petersd66595f2001-02-04 03:09:53 +0000615Standard library
616
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000617- pyexpat now detects the expat version if expat.h defines it. A
618 number of additional handlers are provided, which are only available
619 since expat 1.95. In addition, the methods SetParamEntityParsing and
620 GetInputContext of Parser objects are available with 1.95.x
621 only. Parser objects now provide the ordered_attributes and
622 specified_attributes attributes. A new module expat.model was added,
623 which offers a number of additional constants if 1.95.x is used.
624
625- xml.dom offers the new functions registerDOMImplementation and
626 getDOMImplementation.
627
628- xml.dom.minidom offers a toprettyxml method. A number of DOM
629 conformance issues have been resolved. In particular, Element now
630 has an hasAttributes method, and the handling of namespaces was
631 improved.
632
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +0000633- Ka-Ping Yee contributed two new modules: inspect.py, a module for
634 getting information about live Python code, and pydoc.py, a module
635 for interactively converting docstrings to HTML or text.
636 Tools/scripts/pydoc, which is now automatically installed into
Tim Peters1eff7962001-03-01 02:31:33 +0000637 <prefix>/bin, uses pydoc.py to display documentation; try running
Guido van Rossume3955a82001-03-02 14:05:59 +0000638 "pydoc -h" for instructions. "pydoc -g" pops up a small GUI that
639 lets you browse the module docstrings using a web browser.
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +0000640
Tim Peters1eff7962001-03-01 02:31:33 +0000641- New library module difflib.py, primarily packaging the SequenceMatcher
642 class at the heart of the popular ndiff.py file-comparison tool.
643
644- doctest.py (a framework for verifying Python code examples in docstrings)
645 is now part of the std library.
646
Tim Petersd66595f2001-02-04 03:09:53 +0000647Windows changes
648
Guido van Rossume3955a82001-03-02 14:05:59 +0000649- A new entry in the Start menu, "Module Docs", runs "pydoc -g" -- a
650 small GUI that lets you browse the module docstrings using your
651 default web browser.
652
Tim Peters1eff7962001-03-01 02:31:33 +0000653- Import is now case-sensitive. PEP 235 (Import on Case-Insensitive
654 Platforms) is implemented. See
655
656 http://python.sourceforge.net/peps/pep-0235.html
657
658 for full details, especially the "Current Lower-Left Semantics" section.
659 The new Windows import rules are simpler than before:
660
661 A. If the PYTHONCASEOK environment variable exists, same as
662 before: silently accept the first case-insensitive match of any
663 kind; raise ImportError if none found.
664
665 B. Else search sys.path for the first case-sensitive match; raise
666 ImportError if none found.
667
668 The same rules have been implented on other platforms with case-
669 insensitive but case-preserving filesystems too (including Cygwin, and
670 several flavors of Macintosh operating systems).
Tim Petersd66595f2001-02-04 03:09:53 +0000671
Tim Peters25a9ce32001-02-19 07:06:36 +0000672- winsound module: Under Win9x, winsound.Beep() now attempts to simulate
673 what it's supposed to do (and does do under NT and 2000) via direct
674 port manipulation. It's unknown whether this will work on all systems,
Tim Peters1eff7962001-03-01 02:31:33 +0000675 but it does work on my Win98SE systems now and was known to be useless on
Tim Peters25a9ce32001-02-19 07:06:36 +0000676 all Win9x systems before.
677
Tim Peters1eff7962001-03-01 02:31:33 +0000678- Build: Subproject _test (effectively) renamed to _testcapi.
679
Tim Peters2fe289a2001-03-01 22:19:38 +0000680New platforms
681
682- 2.1 should compile and run out of the box under MacOS X, even using HFS+.
683 Thanks to Steven Majewski!
684
685- 2.1 should compile and run out of the box on Cygwin. Thanks to Jason
686 Tishler!
687
Guido van Rossum9089b272001-03-02 06:49:50 +0000688- 2.1 contains new files and patches for RISCOS, thanks to Dietmar
689 Schwertberger! See RISCOS/README for more information -- it seems
690 that because of the bizarre filename conventions on RISCOS, no port
691 to that platform is easy. Note that the new variable os.endsep is
692 silently supported in order to make life easier on this platform,
693 but we don't advertise it because it's not worth for most folks to
694 care about RISCOS portability.
695
Tim Peters25a9ce32001-02-19 07:06:36 +0000696
Tim Petersd7b5e882001-01-25 03:36:26 +0000697What's New in Python 2.1 alpha 2?
698=================================
Tim Peters40ead762001-01-27 05:35:26 +0000699
Tim Petersd7b5e882001-01-25 03:36:26 +0000700Core language, builtins, and interpreter
701
Jeremy Hylton4589bd82001-02-01 20:38:45 +0000702- Scopes nest. If a name is used in a function or class, but is not
703 local, the definition in the nearest enclosing function scope will
704 be used. One consequence of this change is that lambda statements
705 could reference variables in the namespaces where the lambda is
706 defined. In some unusual cases, this change will break code.
707
708 In all previous version of Python, names were resolved in exactly
709 three namespaces -- the local namespace, the global namespace, and
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000710 the builtin namespace. According to this old definition, if a
Jeremy Hylton4589bd82001-02-01 20:38:45 +0000711 function A is defined within a function B, the names bound in B are
712 not visible in A. The new rules make names bound in B visible in A,
713 unless A contains a name binding that hides the binding in B.
714
715 Section 4.1 of the reference manual describes the new scoping rules
716 in detail. The test script in Lib/test/test_scope.py demonstrates
717 some of the effects of the change.
718
719 The new rules will cause existing code to break if it defines nested
720 functions where an outer function has local variables with the same
721 name as globals or builtins used by the inner function. Example:
722
723 def munge(str):
724 def helper(x):
725 return str(x)
726 if type(str) != type(''):
727 str = helper(str)
728 return str.strip()
729
730 Under the old rules, the name str in helper() is bound to the
731 builtin function str(). Under the new rules, it will be bound to
732 the argument named str and an error will occur when helper() is
733 called.
734
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000735- The compiler will report a SyntaxError if "from ... import *" occurs
736 in a function or class scope. The language reference has documented
737 that this case is illegal, but the compiler never checked for it.
738 The recent introduction of nested scope makes the meaning of this
739 form of name binding ambiguous. In a future release, the compiler
740 may allow this form when there is no possibility of ambiguity.
741
Tim Peters40ead762001-01-27 05:35:26 +0000742- repr(string) is easier to read, now using hex escapes instead of octal,
743 and using \t, \n and \r instead of \011, \012 and \015 (respectively):
744
745 >>> "\texample \r\n" + chr(0) + chr(255)
746 '\texample \r\n\x00\xff' # in 2.1
747 '\011example \015\012\000\377' # in 2.0
748
Moshe Zadka6af0ce02001-01-29 06:41:00 +0000749- Functions are now compared and hashed by identity, not by value, since
750 the func_code attribute is writable.
751
Fred Drakefb9d7122001-02-01 20:00:40 +0000752- Weak references (PEP 205) have been added. This involves a few
753 changes in the core, an extension module (_weakref), and a Python
754 module (weakref). The weakref module is the public interface. It
755 includes support for "explicit" weak references, proxy objects, and
756 mappings with weakly held values.
757
Jeremy Hylton0072d5a2001-02-01 22:53:15 +0000758- A 'continue' statement can now appear in a try block within the body
759 of a loop. It is still not possible to use continue in a finally
Tim Peters9ea17ac2001-02-02 05:57:15 +0000760 clause.
Jeremy Hylton0072d5a2001-02-01 22:53:15 +0000761
Tim Petersd7b5e882001-01-25 03:36:26 +0000762Standard library
763
Barry Warsaw30dbd142001-01-31 22:14:01 +0000764- mailbox.py now has a new class, PortableUnixMailbox which is
765 identical to UnixMailbox but uses a more portable scheme for
766 determining From_ separators. Also, the constructors for all the
767 classes in this module have a new optional `factory' argument, which
768 is a callable used when new message classes must be instantiated by
769 the next() method.
770
Tim Petersd7b5e882001-01-25 03:36:26 +0000771- random.py is now self-contained, and offers all the functionality of
772 the now-deprecated whrandom.py. See the docs for details. random.py
773 also supports new functions getstate() and setstate(), for saving
Tim Petersd52269b2001-01-25 06:23:18 +0000774 and restoring the internal state of the generator; and jumpahead(n),
775 for quickly forcing the internal state to be the same as if n calls to
776 random() had been made. The latter is particularly useful for multi-
777 threaded programs, creating one instance of the random.Random() class for
778 each thread, then using .jumpahead() to force each instance to use a
779 non-overlapping segment of the full period.
Tim Petersd7b5e882001-01-25 03:36:26 +0000780
Tim Peters0de88fc2001-02-01 04:59:18 +0000781- random.py's seed() function is new. For bit-for-bit compatibility with
782 prior releases, use the whseed function instead. The new seed function
783 addresses two problems: (1) The old function couldn't produce more than
784 about 2**24 distinct internal states; the new one about 2**45 (the best
785 that can be done in the Wichmann-Hill generator). (2) The old function
786 sometimes produced identical internal states when passed distinct
787 integers, and there was no simple way to predict when that would happen;
788 the new one guarantees to produce distinct internal states for all
789 arguments in [0, 27814431486576L).
790
Jeremy Hylton4c4fda02001-02-02 03:29:24 +0000791- The socket module now supports raw packets on Linux. The socket
792 family is AF_PACKET.
793
Tim Peters9ea17ac2001-02-02 05:57:15 +0000794- test_capi.py is a start at running tests of the Python C API. The tests
795 are implemented by the new Modules/_testmodule.c.
796
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000797- A new extension module, _symtable, provides provisional access to the
798 internal symbol table used by the Python compiler. A higher-level
799 interface will be added on top of _symtable in a future release.
800
Andrew M. Kuchlingdebc3522001-02-22 15:53:21 +0000801- Removed the obsolete soundex module.
802
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000803- xml.dom.minidom now uses the standard DOM exceptions. Node supports
804 the isSameNode method; NamedNodeMap the get method.
805
806- xml.sax.expatreader supports the lexical handler property; it
807 generates comment, startCDATA, and endCDATA events.
808
Tim Petersee826f82001-01-31 19:39:44 +0000809Windows changes
810
811- Build procedure: the zlib project is built in a different way that
812 ensures the zlib header files used can no longer get out of synch with
Tim Peters9ea17ac2001-02-02 05:57:15 +0000813 the zlib binary used. See PCbuild\readme.txt for details. Your old
814 zlib-related directories can be deleted; you'll need to download fresh
815 source for zlib and unpack it into a new directory.
Tim Petersee826f82001-01-31 19:39:44 +0000816
Tim Peters9ea17ac2001-02-02 05:57:15 +0000817- Build: New subproject _test for the benefit of test_capi.py (see above).
818
Tim Petersb16c56f2001-02-02 21:24:51 +0000819- Build: New subproject _symtable, for new DLL _symtable.pyd (a nascent
820 interface to some Python compiler internals).
821
822- Build: Subproject ucnhash is gone, since the code was folded into the
Tim Peters9ea17ac2001-02-02 05:57:15 +0000823 unicodedata subproject.
Tim Petersd7b5e882001-01-25 03:36:26 +0000824
Tim Petersa3a3a032000-11-30 05:22:44 +0000825What's New in Python 2.1 alpha 1?
826=================================
827
828Core language, builtins, and interpreter
829
Marc-André Lemburgebb195b2001-01-20 10:34:52 +0000830- There is a new Unicode companion to the PyObject_Str() API
831 called PyObject_Unicode(). It behaves in the same way as the
832 former, but assures that the returned value is an Unicode object
833 (applying the usual coercion if necessary).
Marc-André Lemburgad7c98e2001-01-17 17:09:53 +0000834
Guido van Rossumf98eda02001-01-17 15:54:45 +0000835- The comparison operators support "rich comparison overloading" (PEP
836 207). C extension types can provide a rich comparison function in
837 the new tp_richcompare slot in the type object. The cmp() function
838 and the C function PyObject_Compare() first try the new rich
839 comparison operators before trying the old 3-way comparison. There
840 is also a new C API PyObject_RichCompare() (which also falls back on
841 the old 3-way comparison, but does not constrain the outcome of the
842 rich comparison to a Boolean result).
843
844 The rich comparison function takes two objects (at least one of
845 which is guaranteed to have the type that provided the function) and
846 an integer indicating the opcode, which can be Py_LT, Py_LE, Py_EQ,
847 Py_NE, Py_GT, Py_GE (for <, <=, ==, !=, >, >=), and returns a Python
848 object, which may be NotImplemented (in which case the tp_compare
849 slot function is used as a fallback, if defined).
850
851 Classes can overload individual comparison operators by defining one
852 or more of the methods__lt__, __le__, __eq__, __ne__, __gt__,
Guido van Rossuma88479f2001-01-18 14:28:08 +0000853 __ge__. There are no explicit "reflected argument" versions of
854 these; instead, __lt__ and __gt__ are each other's reflection,
855 likewise for__le__ and __ge__; __eq__ and __ne__ are their own
856 reflection (similar at the C level). No other implications are
857 made; in particular, Python does not assume that == is the Boolean
858 inverse of !=, or that < is the Boolean inverse of >=. This makes
859 it possible to define types with partial orderings.
Guido van Rossumf98eda02001-01-17 15:54:45 +0000860
861 Classes or types that want to implement (in)equality tests but not
862 the ordering operators (i.e. unordered types) should implement ==
863 and !=, and raise an error for the ordering operators.
864
Guido van Rossuma88479f2001-01-18 14:28:08 +0000865 It is possible to define types whose rich comparison results are not
Guido van Rossumf98eda02001-01-17 15:54:45 +0000866 Boolean; e.g. a matrix type might want to return a matrix of bits
867 for A < B, giving elementwise comparisons. Such types should ensure
868 that any interpretation of their value in a Boolean context raises
869 an exception, e.g. by defining __nonzero__ (or the tp_nonzero slot
870 at the C level) to always raise an exception.
871
Guido van Rossuma88479f2001-01-18 14:28:08 +0000872- Complex numbers use rich comparisons to define == and != but raise
873 an exception for <, <=, > and >=. Unfortunately, this also means
874 that cmp() of two complex numbers raises an exception when the two
875 numbers differ. Since it is not mathematically meaningful to compare
876 complex numbers except for equality, I hope that this doesn't break
877 too much code.
878
Tim Peters3389f192001-02-18 08:48:49 +0000879- The outcome of comparing non-numeric objects of different types is
Tim Peters14495852001-02-18 08:28:33 +0000880 not defined by the language, other than that it's arbitrary but
881 consistent (see the Reference Manual). An implementation detail changed
882 in 2.1a1 such that None now compares less than any other object. Code
883 relying on this new behavior (like code that relied on the previous
884 behavior) does so at its own risk.
885
Barry Warsaw573b5412001-01-15 20:43:18 +0000886- Functions and methods now support getting and setting arbitrarily
887 named attributes (PEP 232). Functions have a new __dict__
888 (a.k.a. func_dict) which hold the function attributes. Methods get
889 and set attributes on their underlying im_func. It is a TypeError
890 to set an attribute on a bound method.
891
Guido van Rossum051e3352001-01-15 19:11:10 +0000892- The xrange() object implementation has been improved so that
893 xrange(sys.maxint) can be used on 64-bit platforms. There's still a
894 limitation that in this case len(xrange(sys.maxint)) can't be
895 calculated, but the common idiom "for i in xrange(sys.maxint)" will
896 work fine as long as the index i doesn't actually reach 2**31.
897 (Python uses regular ints for sequence and string indices; fixing
898 that is much more work.)
899
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000900- Two changes to from...import:
901
Guido van Rossumba381232001-02-03 15:06:40 +0000902 1) "from M import X" now works even if (after loading module M)
903 sys.modules['M'] is not a real module; it's basically a getattr()
904 operation with AttributeError exceptions changed into ImportError.
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000905
906 2) "from M import *" now looks for M.__all__ to decide which names to
907 import; if M.__all__ doesn't exist, it uses M.__dict__.keys() but
908 filters out names starting with '_' as before. Whether or not
909 __all__ exists, there's no restriction on the type of M.
910
Guido van Rossumf61f1662001-01-10 20:13:55 +0000911- File objects have a new method, xreadlines(). This is the fastest
912 way to iterate over all lines in a file:
913
914 for line in file.xreadlines():
915 ...do something to line...
916
917 See the xreadlines module (mentioned below) for how to do this for
918 other file-like objects.
919
920- Even if you don't use file.xreadlines(), you may expect a speedup on
921 line-by-line input. The file.readline() method has been optimized
Tim Petersf29b64d2001-01-15 06:33:19 +0000922 quite a bit in platform-specific ways: on systems (like Linux) that
923 support flockfile(), getc_unlocked(), and funlockfile(), those are
924 used by default. On systems (like Windows) without getc_unlocked(),
925 a complicated (but still thread-safe) method using fgets() is used by
926 default.
927
Tim Petersd52269b2001-01-25 06:23:18 +0000928 You can force use of the fgets() method by #define'ing
929 USE_FGETS_IN_GETLINE at build time (it may be faster than
Tim Petersf29b64d2001-01-15 06:33:19 +0000930 getc_unlocked()).
931
Tim Petersd52269b2001-01-25 06:23:18 +0000932 You can force fgets() not to be used by #define'ing
933 DONT_USE_FGETS_IN_GETLINE (this is the first thing to try if std test
Tim Petersf29b64d2001-01-15 06:33:19 +0000934 test_bufio.py fails -- and let us know if it does!).
935
936- In addition, the fileinput module, while still slower than the other
937 methods on most platforms, has been sped up too, by using
938 file.readlines(sizehint).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000939
940- Support for run-time warnings has been added, including a new
941 command line option (-W) to specify the disposition of warnings.
942 See the description of the warnings module below.
943
944- Extensive changes have been made to the coercion code. This mostly
945 affects extension modules (which can now implement mixed-type
946 numerical operators without having to use coercion), but
947 occasionally, in boundary cases the coercion semantics have changed
948 subtly. Since this was a terrible gray area of the language, this
Guido van Rossumae72d872001-01-11 15:00:14 +0000949 is considered an improvement. Also note that __rcmp__ is no longer
Guido van Rossumf61f1662001-01-10 20:13:55 +0000950 supported -- instead of calling __rcmp__, __cmp__ is called with
Guido van Rossuma88479f2001-01-18 14:28:08 +0000951 reflected arguments.
Guido van Rossumf61f1662001-01-10 20:13:55 +0000952
Guido van Rossumf98eda02001-01-17 15:54:45 +0000953- In connection with the coercion changes, a new built-in singleton
954 object, NotImplemented is defined. This can be returned for
955 operations that wish to indicate they are not implemented for a
956 particular combination of arguments. From C, this is
957 Py_NotImplemented.
958
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000959- The interpreter accepts now bytecode files on the command line even
960 if they do not have a .pyc or .pyo extension. On Linux, after executing
961
Martin v. Löwise214baa2001-02-04 22:37:56 +0000962import imp,sys,string
963magic = string.join(["\\x%.2x" % ord(c) for c in imp.get_magic()],"")
964reg = ':pyc:M::%s::%s:' % (magic, sys.executable)
965open("/proc/sys/fs/binfmt_misc/register","wb").write(reg)
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000966
967 any byte code file can be used as an executable (i.e. as an argument
968 to execve(2)).
969
Tim Peters9940b802000-12-01 07:59:35 +0000970- %[xXo] formats of negative Python longs now produce a sign
Tim Petersa3a3a032000-11-30 05:22:44 +0000971 character. In 1.6 and earlier, they never produced a sign,
972 and raised an error if the value of the long was too large
973 to fit in a Python int. In 2.0, they produced a sign if and
974 only if too large to fit in an int. This was inconsistent
975 across platforms (because the size of an int varies across
976 platforms), and inconsistent with hex() and oct(). Example:
977
978 >>> "%x" % -0x42L
Tim Peters9940b802000-12-01 07:59:35 +0000979 '-42' # in 2.1
Tim Petersa3a3a032000-11-30 05:22:44 +0000980 'ffffffbe' # in 2.0 and before, on 32-bit machines
981 >>> hex(-0x42L)
982 '-0x42L' # in all versions of Python
983
Tim Peters9940b802000-12-01 07:59:35 +0000984 The behavior of %d formats for negative Python longs remains
985 the same as in 2.0 (although in 1.6 and before, they raised
986 an error if the long didn't fit in a Python int).
987
988 %u formats don't make sense for Python longs, but are allowed
989 and treated the same as %d in 2.1. In 2.0, a negative long
990 formatted via %u produced a sign if and only if too large to
991 fit in an int. In 1.6 and earlier, a negative long formatted
992 via %u raised an error if it was too big to fit in an int.
993
Guido van Rossum3661d392000-12-12 22:10:31 +0000994- Dictionary objects have an odd new method, popitem(). This removes
995 an arbitrary item from the dictionary and returns it (in the form of
996 a (key, value) pair). This can be useful for algorithms that use a
997 dictionary as a bag of "to do" items and repeatedly need to pick one
998 item. Such algorithms normally end up running in quadratic time;
999 using popitem() they can usually be made to run in linear time.
1000
Tim Peters36cdad12000-12-29 02:06:45 +00001001Standard library
1002
Thomas Woutersfe385252001-01-19 23:16:56 +00001003- In the time module, the time argument to the functions strftime,
1004 localtime, gmtime, asctime and ctime is now optional, defaulting to
1005 the current time (in the local timezone).
1006
Guido van Rossumda91f222001-01-15 16:36:08 +00001007- The ftplib module now defaults to passive mode, which is deemed a
1008 more useful default given that clients are often inside firewalls
1009 these days. Note that this could break if ftplib is used to connect
1010 to a *server* that is inside a firewall, from outside; this is
1011 expected to be a very rare situation. To fix that, you can call
1012 ftp.set_pasv(0).
1013
Martin v. Löwis10a27872001-01-13 09:54:41 +00001014- The module site now treats .pth files not only for path configuration,
1015 but also supports extensions to the initialization code: Lines starting
1016 with import are executed.
1017
Guido van Rossumf61f1662001-01-10 20:13:55 +00001018- There's a new module, warnings, which implements a mechanism for
1019 issuing and filtering warnings. There are some new built-in
1020 exceptions that serve as warning categories, and a new command line
1021 option, -W, to control warnings (e.g. -Wi ignores all warnings, -We
1022 turns warnings into errors). warnings.warn(message[, category])
1023 issues a warning message; this can also be called from C as
1024 PyErr_Warn(category, message).
1025
1026- A new module xreadlines was added. This exports a single factory
1027 function, xreadlines(). The intention is that this code is the
1028 absolutely fastest way to iterate over all lines in an open
1029 file(-like) object:
1030
1031 import xreadlines
1032 for line in xreadlines.xreadlines(file):
1033 ...do something to line...
1034
1035 This is equivalent to the previous the speed record holder using
1036 file.readlines(sizehint). Note that if file is a real file object
1037 (as opposed to a file-like object), this is equivalent:
1038
1039 for line in file.xreadlines():
1040 ...do something to line...
1041
Tim Peters36cdad12000-12-29 02:06:45 +00001042- The bisect module has new functions bisect_left, insort_left,
1043 bisect_right and insort_right. The old names bisect and insort
1044 are now aliases for bisect_right and insort_right. XXX_right
1045 and XXX_left methods differ in what happens when the new element
1046 compares equal to one or more elements already in the list: the
1047 XXX_left methods insert to the left, the XXX_right methods to the
Tim Peters742bb6f2001-01-05 08:05:32 +00001048 right. Code that doesn't care where equal elements end up should
1049 continue to use the old, short names ("bisect" and "insort").
Tim Peters36cdad12000-12-29 02:06:45 +00001050
Andrew M. Kuchlingf6f3a892001-01-13 14:53:34 +00001051- The new curses.panel module wraps the panel library that forms part
1052 of SYSV curses and ncurses. Contributed by Thomas Gellekum.
1053
Guido van Rossumf61f1662001-01-10 20:13:55 +00001054- The SocketServer module now sets the allow_reuse_address flag by
1055 default in the TCPServer class.
1056
1057- A new function, sys._getframe(), returns the stack frame pointer of
1058 the caller. This is intended only as a building block for
1059 higher-level mechanisms such as string interpolation.
1060
Martin v. Löwis2a5130e2001-02-27 04:21:58 +00001061- The pyexpat module supports a number of new handlers, which are
1062 available only in expat 1.2. If invocation of a callback fails, it
1063 will report an additional frame in the traceback. Parser objects
1064 participate now in garbage collection. If expat reports an unknown
1065 encoding, pyexpat will try to use a Python codec; that works only
1066 for single-byte charsets. The parser type objects is exposed as
1067 XMLParserObject.
1068
1069- xml.dom now offers standard definitions for symbolic node type and
1070 exception code constants, and a hierarchy of DOM exceptions. minidom
1071 was adjusted to use them.
1072
1073- The conformance of xml.dom.minidom to the DOM specification was
1074 improved. It detects a number of additional error cases; the
1075 previous/next relationship works even when the tree is modified;
1076 Node supports the normalize() method; NamedNodeMap, DocumentType and
1077 DOMImplementation classes were added; Element supports the
1078 hasAttribute and hasAttributeNS methods; and Text supports the splitText
1079 method.
1080
Guido van Rossumf61f1662001-01-10 20:13:55 +00001081Build issues
1082
Guido van Rossum1e33bdc2001-01-23 03:17:00 +00001083- For Unix (and Unix-compatible) builds, configuration and building of
1084 extension modules is now greatly automated. Rather than having to
1085 edit the Modules/Setup file to indicate which modules should be
1086 built and where their include files and libraries are, a
1087 distutils-based setup.py script now takes care of building most
1088 extension modules. All extension modules built this way are built
1089 as shared libraries. Only a few modules that must be linked
1090 statically are still listed in the Setup file; you won't need to
1091 edit their configuration.
1092
1093- Python should now build out of the box on Cygwin. If it doesn't,
1094 mail to Jason Tishler (jlt63 at users.sourceforge.net).
Guido van Rossumf61f1662001-01-10 20:13:55 +00001095
1096- Python now always uses its own (renamed) implementation of getopt()
1097 -- there's too much variation among C library getopt()
1098 implementations.
1099
1100- C++ compilers are better supported; the CXX macro is always set to a
1101 C++ compiler if one is found.
Tim Peters36cdad12000-12-29 02:06:45 +00001102
Tim Petersd92dfe02000-12-12 01:18:41 +00001103Windows changes
1104
1105- select module: By default under Windows, a select() call
1106 can specify no more than 64 sockets. Python now boosts
1107 this Microsoft default to 512. If you need even more than
1108 that, see the MS docs (you'll need to #define FD_SETSIZE
1109 and recompile Python from source).
1110
Guido van Rossumf61f1662001-01-10 20:13:55 +00001111- Support for Windows 3.1, DOS and OS/2 is gone. The Lib/dos-8x3
1112 subdirectory is no more!
1113
Tim Petersa3a3a032000-11-30 05:22:44 +00001114
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001115What's New in Python 2.0?
Fred Drake1a640502000-10-16 20:27:25 +00001116=========================
Guido van Rossum61000331997-08-15 04:39:58 +00001117
Guido van Rossum8ed602b2000-09-01 22:34:33 +00001118Below is a list of all relevant changes since release 1.6. Older
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001119changes are in the file HISTORY. If you are making the jump directly
1120from Python 1.5.2 to 2.0, make sure to read the section for 1.6 in the
1121HISTORY file! Many important changes listed there.
Guido van Rossum61000331997-08-15 04:39:58 +00001122
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001123Alternatively, a good overview of the changes between 1.5.2 and 2.0 is
1124the document "What's New in Python 2.0" by Kuchling and Moshe Zadka:
1125http://starship.python.net/crew/amk/python/writing/new-python/.
Guido van Rossum1f83cce1997-10-06 21:04:35 +00001126
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001127--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)
Guido van Rossum437cfe81999-04-08 20:17:57 +00001128
1129======================================================================
1130
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001131What's new in 2.0 (since release candidate 1)?
1132==============================================
1133
1134Standard library
1135
1136- The copy_reg module was modified to clarify its intended use: to
1137 register pickle support for extension types, not for classes.
1138 pickle() will raise a TypeError if it is passed a class.
1139
1140- Fixed a bug in gettext's "normalize and expand" code that prevented
1141 it from finding an existing .mo file.
1142
1143- Restored support for HTTP/0.9 servers in httplib.
1144
Tim Peters989b7b92000-10-16 20:24:53 +00001145- The math module was changed to stop raising OverflowError in case of
1146 underflow, and return 0 instead in underflow cases. Whether Python
1147 used to raise OverflowError in case of underflow was platform-
1148 dependent (it did when the platform math library set errno to ERANGE
1149 on underflow).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001150
1151- Fixed a bug in StringIO that occurred when the file position was not
1152 at the end of the file and write() was called with enough data to
1153 extend past the end of the file.
1154
1155- Fixed a bug that caused Tkinter error messages to get lost on
1156 Windows. The bug was fixed by replacing direct use of
1157 interp->result with Tcl_GetStringResult(interp).
1158
1159- Fixed bug in urllib2 that caused it to fail when it received an HTTP
1160 redirect response.
1161
1162- Several changes were made to distutils: Some debugging code was
1163 removed from util. Fixed the installer used when an external zip
1164 program (like WinZip) is not found; the source code for this
1165 installer is in Misc/distutils. check_lib() was modified to behave
1166 more like AC_CHECK_LIB by add other_libraries() as a parameter. The
1167 test for whether installed modules are on sys.path was changed to
1168 use both normcase() and normpath().
1169
Jeremy Hyltond867a2c2000-10-16 20:41:38 +00001170- Several minor bugs were fixed in the xml package (the minidom,
1171 pulldom, expatreader, and saxutils modules).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001172
1173- The regression test driver (regrtest.py) behavior when invoked with
1174 -l changed: It now reports a count of objects that are recognized as
1175 garbage but not freed by the garbage collector.
1176
Tim Peters989b7b92000-10-16 20:24:53 +00001177- The regression test for the math module was changed to test
1178 exceptional behavior when the test is run in verbose mode. Python
1179 cannot yet guarantee consistent exception behavior across platforms,
1180 so the exception part of test_math is run only in verbose mode, and
1181 may fail on your platform.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001182
1183Internals
1184
1185- PyOS_CheckStack() has been disabled on Win64, where it caused
1186 test_sre to fail.
1187
1188Build issues
1189
1190- Changed compiler flags, so that gcc is always invoked with -Wall and
1191 -Wstrict-prototypes. Users compiling Python with GCC should see
1192 exactly one warning, except if they have passed configure the
Tim Peters989b7b92000-10-16 20:24:53 +00001193 --with-pydebug flag. The expected warning is for getopt() in
Tim Petersadfb94f2000-10-16 20:51:33 +00001194 Modules/main.c. This warning will be fixed for Python 2.1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001195
Tim Petersa3a3a032000-11-30 05:22:44 +00001196- Fixed configure to add -threads argument during linking on OSF1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001197
1198Tools and other miscellany
1199
1200- The compiler in Tools/compiler was updated to support the new
1201 language features introduced in 2.0: extended print statement, list
1202 comprehensions, and augmented assignments. The new compiler should
1203 also be backwards compatible with Python 1.5.2; the compiler will
1204 always generate code for the version of the interpreter it runs
Tim Petersa3a3a032000-11-30 05:22:44 +00001205 under.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001206
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001207What's new in 2.0 release candidate 1 (since beta 2)?
1208=====================================================
1209
Jeremy Hylton6040aaa2000-10-09 21:27:22 +00001210What is release candidate 1?
1211
1212We believe that release candidate 1 will fix all known bugs that we
1213intend to fix for the 2.0 final release. This release should be a bit
1214more stable than the previous betas. We would like to see even more
1215widespread testing before the final release, so we are producing this
1216release candidate. The final release will be exactly the same unless
1217any show-stopping (or brown bag) bugs are found by testers of the
1218release candidate.
1219
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001220All the changes since the last beta release are bug fixes or changes
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001221to support building Python for specific platforms.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001222
1223Core language, builtins, and interpreter
1224
1225- A bug that caused crashes when __coerce__ was used with augmented
1226 assignment, e.g. +=, was fixed.
1227
1228- Raise ZeroDivisionError when raising zero to a negative number,
1229 e.g. 0.0 ** -2.0. Note that math.pow is unrelated to the builtin
1230 power operator and the result of math.pow(0.0, -2.0) will vary by
1231 platform. On Linux, it raises a ValueError.
1232
1233- A bug in Unicode string interpolation was fixed that occasionally
1234 caused errors with formats including "%%". For example, the
1235 following expression "%% %s" % u"abc" no longer raises a TypeError.
1236
1237- Compilation of deeply nested expressions raises MemoryError instead
1238 of SyntaxError, e.g. eval("[" * 50 + "]" * 50).
1239
1240- In 2.0b2 on Windows, the interpreter wrote .pyc files in text mode,
1241 rendering them useless. They are now written in binary mode again.
1242
1243Standard library
1244
1245- Keyword arguments are now accepted for most pattern and match object
1246 methods in SRE, the standard regular expression engine.
1247
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001248- In SRE, fixed error with negative lookahead and lookbehind that
Jeremy Hylton32e20ff2000-10-09 19:48:11 +00001249 manifested itself as a runtime error in patterns like "(?<!abc)(def)".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001250
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001251- Several bugs in the Unicode handling and error handling in _tkinter
1252 were fixed.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001253
1254- Fix memory management errors in Merge() and Tkapp_Call() routines.
1255
1256- Several changes were made to cStringIO to make it compatible with
1257 the file-like object interface and with StringIO. If operations are
1258 performed on a closed object, an exception is raised. The truncate
1259 method now accepts a position argument and readline accepts a size
Tim Petersa3a3a032000-11-30 05:22:44 +00001260 argument.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001261
1262- There were many changes made to the linuxaudiodev module and its
1263 test suite; as a result, a short, unexpected audio sample should now
Tim Petersa3a3a032000-11-30 05:22:44 +00001264 play when the regression test is run.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001265
1266 Note that this module is named poorly, because it should work
1267 correctly on any platform that supports the Open Sound System
Tim Petersa3a3a032000-11-30 05:22:44 +00001268 (OSS).
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001269
1270 The module now raises exceptions when errors occur instead of
1271 crashing. It also defines the AFMT_A_LAW format (logarithmic A-law
1272 audio) and defines a getptr() method that calls the
1273 SNDCTL_DSP_GETxPTR ioctl defined in the OSS Programmer's Guide.
1274
1275- The library_version attribute, introduced in an earlier beta, was
1276 removed because it can not be supported with early versions of the C
1277 readline library, which provides no way to determine the version at
1278 compile-time.
1279
1280- The binascii module is now enabled on Win64.
1281
Tim Peters46446d62000-10-09 21:19:31 +00001282- tokenize.py no longer suffers "recursion depth" errors when parsing
1283 programs with very long string literals.
1284
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001285Internals
1286
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001287- Fixed several buffer overflow vulnerabilities in calculate_path(),
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001288 which is called when the interpreter starts up to determine where
1289 the standard library is installed. These vulnerabilities affect all
1290 previous versions of Python and can be exploited by setting very
1291 long values for PYTHONHOME or argv[0]. The risk is greatest for a
1292 setuid Python script, although use of the wrapper in
1293 Misc/setuid-prog.c will eliminate the vulnerability.
1294
1295- Fixed garbage collection bugs in instance creation that were
1296 triggered when errors occurred during initialization. The solution,
1297 applied in cPickle and in PyInstance_New(), is to call
1298 PyObject_GC_Init() after the initialization of the object's
1299 container attributes is complete.
1300
1301- pyexpat adds definitions of PyModule_AddStringConstant and
1302 PyModule_AddObject if the Python version is less than 2.0, which
1303 provides compatibility with PyXML on Python 1.5.2.
1304
1305- If the platform has a bogus definition for LONG_BIT (the number of
1306 bits in a long), an error will be reported at compile time.
1307
1308- Fix bugs in _PyTuple_Resize() which caused hard-to-interpret garbage
1309 collection crashes and possibly other, unreported crashes.
1310
1311- Fixed a memory leak in _PyUnicode_Fini().
1312
1313Build issues
1314
1315- configure now accepts a --with-suffix option that specifies the
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001316 executable suffix. This is useful for builds on Cygwin and Mac OS
Tim Petersa3a3a032000-11-30 05:22:44 +00001317 X, for example.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001318
1319- The mmap.PAGESIZE constant is now initialized using sysconf when
1320 possible, which eliminates a dependency on -lucb for Reliant UNIX.
1321
1322- The md5 file should now compile on all platforms.
1323
1324- The select module now compiles on platforms that do not define
1325 POLLRDNORM and related constants.
1326
1327- Darwin (Mac OS X): Initial support for static builds on this
Tim Petersa3a3a032000-11-30 05:22:44 +00001328 platform.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001329
Jeremy Hylton10921202000-10-09 18:34:12 +00001330- BeOS: A number of changes were made to the build and installation
1331 process. ar-fake now operates on a directory of object files.
1332 dl_export.h is gone, and its macros now appear on the mwcc command
1333 line during build on PPC BeOS.
1334
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001335- Platform directory in lib/python2.0 is "plat-beos5" (or
Jeremy Hylton10921202000-10-09 18:34:12 +00001336 "plat-beos4", if building on BeOS 4.5), rather than "plat-beos".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001337
1338- Cygwin: Support for shared libraries, Tkinter, and sockets.
1339
1340- SunOS 4.1.4_JL: Fix test for directory existence in configure.
1341
1342Tools and other miscellany
1343
1344- Removed debugging prints from main used with freeze.
1345
Tim Peters46446d62000-10-09 21:19:31 +00001346- IDLE auto-indent no longer crashes when it encounters Unicode
1347 characters.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001348
1349What's new in 2.0 beta 2 (since beta 1)?
1350========================================
1351
1352Core language, builtins, and interpreter
1353
Tim Peters482c0212000-09-26 06:33:09 +00001354- Add support for unbounded ints in %d,i,u,x,X,o formats; for example
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001355 "%d" % 2L**64 == "18446744073709551616".
Jeremy Hylton1b618592000-09-26 05:32:36 +00001356
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001357- Add -h and -V command line options to print the usage message and
1358 Python version number and exit immediately.
1359
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001360- eval() and exec accept Unicode objects as code parameters.
1361
1362- getattr() and setattr() now also accept Unicode objects for the
1363 attribute name, which are converted to strings using the default
1364 encoding before lookup.
1365
1366- Multiplication on string and Unicode now does proper bounds
1367 checking; e.g. 'a' * 65536 * 65536 will raise ValueError, "repeated
1368 string is too long."
1369
1370- Better error message when continue is found in try statement in a
Tim Petersa3a3a032000-11-30 05:22:44 +00001371 loop.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001372
Jeremy Hylton1b618592000-09-26 05:32:36 +00001373
1374Standard library and extensions
1375
Guido van Rossum5b08f132001-04-16 02:05:23 +00001376- socket module: the OpenSSL code now adds support for RAND_status()
1377 and EGD (Entropy Gathering Device).
1378
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001379- array: reverse() method of array now works. buffer_info() now does
Jeremy Hylton1b618592000-09-26 05:32:36 +00001380 argument checking; it still takes no arguments.
1381
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001382- asyncore/asynchat: Included most recent version from Sam Rushing.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001383
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001384- cgi: Accept '&' or ';' as separator characters when parsing form data.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001385
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001386- CGIHTTPServer: Now works on Windows (and perhaps even Mac).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001387
1388- ConfigParser: When reading the file, options spelled in upper case
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001389 letters are now correctly converted to lowercase.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001390
1391- copy: Copy Unicode objects atomically.
1392
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001393- cPickle: Fail gracefully when copy_reg can't be imported.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001394
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001395- cStringIO: Implemented readlines() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001396
Fred Drake67233bc2000-09-26 16:40:27 +00001397- dbm: Add get() and setdefault() methods to dbm object. Add constant
1398 `library' to module that names the library used. Added doc strings
1399 and method names to error messages. Uses configure to determine
1400 which ndbm.h file to include; Berkeley DB's nbdm and GDBM's ndbm is
1401 now available options.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001402
1403- distutils: Update to version 0.9.3.
1404
1405- dl: Add several dl.RTLD_ constants.
1406
1407- fpectl: Now supported on FreeBSD.
1408
1409- gc: Add DEBUG_SAVEALL option. When enabled all garbage objects
1410 found by the collector will be saved in gc.garbage. This is useful
1411 for debugging a program that creates reference cycles.
1412
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001413- httplib: Three changes: Restore support for set_debuglevel feature
Jeremy Hylton1b618592000-09-26 05:32:36 +00001414 of HTTP class. Do not close socket on zero-length response. Do not
1415 crash when server sends invalid content-length header.
1416
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001417- mailbox: Mailbox class conforms better to qmail specifications.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001418
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001419- marshal: When reading a short, sign-extend on platforms where shorts
1420 are bigger than 16 bits. When reading a long, repair the unportable
1421 sign extension that was being done for 64-bit machines. (It assumed
1422 that signed right shift sign-extends.)
1423
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001424- operator: Add contains(), invert(), __invert__() as aliases for
1425 __contains__(), inv(), and __inv__() respectively.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001426
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001427- os: Add support for popen2() and popen3() on all platforms where
1428 fork() exists. (popen4() is still in the works.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00001429
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001430- os: (Windows only:) Add startfile() function that acts like double-
Tim Peters482c0212000-09-26 06:33:09 +00001431 clicking on a file in Explorer (or passing the file name to the
1432 DOS "start" command).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001433
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001434- os.path: (Windows, DOS:) Treat trailing colon correctly in
Tim Peters482c0212000-09-26 06:33:09 +00001435 os.path.join. os.path.join("a:", "b") yields "a:b".
Jeremy Hylton1b618592000-09-26 05:32:36 +00001436
1437- pickle: Now raises ValueError when an invalid pickle that contains
1438 a non-string repr where a string repr was expected. This behavior
1439 matches cPickle.
1440
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001441- posixfile: Remove broken __del__() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001442
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001443- py_compile: support CR+LF line terminators in source file.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001444
1445- readline: Does not immediately exit when ^C is hit when readline and
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001446 threads are configured. Adds definition of rl_library_version. (The
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001447 latter addition requires GNU readline 2.2 or later.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00001448
1449- rfc822: Domain literals returned by AddrlistClass method
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001450 getdomainliteral() are now properly wrapped in brackets.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001451
1452- site: sys.setdefaultencoding() should only be called in case the
Tim Peters482c0212000-09-26 06:33:09 +00001453 standard default encoding ("ascii") is changed. This saves quite a
Jeremy Hylton1b618592000-09-26 05:32:36 +00001454 few cycles during startup since the first call to
1455 setdefaultencoding() will initialize the codec registry and the
1456 encodings package.
1457
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001458- socket: Support for size hint in readlines() method of object returned
1459 by makefile().
Jeremy Hylton1b618592000-09-26 05:32:36 +00001460
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001461- sre: Added experimental expand() method to match objects. Does not
Jeremy Hylton625915e2000-10-02 13:43:33 +00001462 use buffer interface on Unicode strings. Does not hang if group id
Jeremy Hylton1b618592000-09-26 05:32:36 +00001463 is followed by whitespace.
1464
Tim Petersa3a3a032000-11-30 05:22:44 +00001465- StringIO: Size hint in readlines() is now supported as documented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001466
1467- struct: Check ranges for bytes and shorts.
1468
1469- urllib: Improved handling of win32 proxy settings. Fixed quote and
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001470 quote_plus functions so that the always encode a comma.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001471
1472- Tkinter: Image objects are now guaranteed to have unique ids. Set
1473 event.delta to zero if Tk version doesn't support mousewheel.
1474 Removed some debugging prints.
1475
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001476- UserList: now implements __contains__().
Jeremy Hylton1b618592000-09-26 05:32:36 +00001477
Fred Drake67233bc2000-09-26 16:40:27 +00001478- webbrowser: On Windows, use os.startfile() instead of os.popen(),
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001479 which works around a bug in Norton AntiVirus 2000 that leads directly
1480 to a Blue Screen freeze.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001481
1482- xml: New version detection code allows PyXML to override standard
1483 XML package if PyXML version is greater than 0.6.1.
1484
Fred Drake64bb3802000-09-26 16:21:35 +00001485- xml.dom: DOM level 1 support for basic XML. Includes xml.dom.minidom
1486 (conventional DOM), and xml.dom.pulldom, which allows building the DOM
1487 tree only for nodes which are sufficiently interesting to a specific
1488 application. Does not provide the HTML-specific extensions. Still
1489 undocumented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001490
Fred Drake64bb3802000-09-26 16:21:35 +00001491- xml.sax: SAX 2 support for Python, including all the handler
1492 interfaces needed to process XML 1.0 compliant XML. Some
1493 documentation is already available.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001494
Fred Drake64bb3802000-09-26 16:21:35 +00001495- pyexpat: Renamed to xml.parsers.expat since this is part of the new,
1496 packagized XML support.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001497
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001498
Jeremy Hylton1b618592000-09-26 05:32:36 +00001499C API
1500
1501- Add three new convenience functions for module initialization --
1502 PyModule_AddObject(), PyModule_AddIntConstant(), and
1503 PyModule_AddStringConstant().
1504
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001505- Cleaned up definition of NULL in C source code; all definitions were
Jeremy Hylton1b618592000-09-26 05:32:36 +00001506 removed and add #error to Python.h if NULL isn't defined after
1507 #include of stdio.h.
1508
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001509- Py_PROTO() macros that were removed in 2.0b1 have been restored for
Jeremy Hylton1b618592000-09-26 05:32:36 +00001510 backwards compatibility (at the source level) with old extensions.
1511
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001512- A wrapper API was added for signal() and sigaction(). Instead of
1513 either function, always use PyOS_getsig() to get a signal handler
1514 and PyOS_setsig() to set one. A new convenience typedef
1515 PyOS_sighandler_t is defined for the type of signal handlers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001516
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001517- Add PyString_AsStringAndSize() function that provides access to the
Jeremy Hylton1b618592000-09-26 05:32:36 +00001518 internal data buffer and size of a string object -- or the default
1519 encoded version of a Unicode object.
1520
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001521- PyString_Size() and PyString_AsString() accept Unicode objects.
1522
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001523- The standard header <limits.h> is now included by Python.h (if it
Fred Drake64bb3802000-09-26 16:21:35 +00001524 exists). INT_MAX and LONG_MAX will always be defined, even if
1525 <limits.h> is not available.
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001526
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001527- PyFloat_FromString takes a second argument, pend, that was
1528 effectively useless. It is now officially useless but preserved for
1529 backwards compatibility. If the pend argument is not NULL, *pend is
1530 set to NULL.
1531
1532- PyObject_GetAttr() and PyObject_SetAttr() now accept Unicode objects
1533 for the attribute name. See note on getattr() above.
1534
1535- A few bug fixes to argument processing for Unicode.
1536 PyArg_ParseTupleAndKeywords() now accepts "es#" and "es".
1537 PyArg_Parse() special cases "s#" for Unicode objects; it returns a
1538 pointer to the default encoded string data instead of to the raw
Tim Petersa3a3a032000-11-30 05:22:44 +00001539 UTF-16.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001540
1541- Py_BuildValue accepts B format (for bgen-generated code).
1542
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001543
Jeremy Hylton1b618592000-09-26 05:32:36 +00001544Internals
1545
1546- On Unix, fix code for finding Python installation directory so that
1547 it works when argv[0] is a relative path.
1548
Andrew M. Kuchlinga1099be2000-12-15 01:16:43 +00001549- Added a true unicode_internal_encode() function and fixed the
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001550 unicode_internal_decode function() to support Unicode objects directly
Jeremy Hylton1b618592000-09-26 05:32:36 +00001551 rather than by generating a copy of the object.
1552
Tim Peters482c0212000-09-26 06:33:09 +00001553- Several of the internal Unicode tables are much smaller now, and
1554 the source code should be much friendlier to weaker compilers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001555
Jeremy Hylton97693b02000-09-26 17:42:51 +00001556- In the garbage collector: Fixed bug in collection of tuples. Fixed
1557 bug that caused some instances to be removed from the container set
1558 while they were still live. Fixed parsing in gc.set_debug() for
1559 platforms where sizeof(long) > sizeof(int).
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001560
1561- Fixed refcount problem in instance deallocation that only occurred
1562 when Py_REF_DEBUG was defined and Py_TRACE_REFS was not.
1563
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001564- On Windows, getpythonregpath is now protected against null data in
1565 registry key.
1566
1567- On Unix, create .pyc/.pyo files with O_EXCL flag to avoid a race
Tim Petersa3a3a032000-11-30 05:22:44 +00001568 condition.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001569
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001570
Jeremy Hylton1b618592000-09-26 05:32:36 +00001571Build and platform-specific issues
1572
1573- Better support of GNU Pth via --with-pth configure option.
1574
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001575- Python/C API now properly exposed to dynamically-loaded extension
1576 modules on Reliant UNIX.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001577
1578- Changes for the benefit of SunOS 4.1.4 (really!). mmapmodule.c:
1579 Don't define MS_SYNC to be zero when it is undefined. Added missing
1580 prototypes in posixmodule.c.
1581
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001582- Improved support for HP-UX build. Threads should now be correctly
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001583 configured (on HP-UX 10.20 and 11.00).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001584
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001585- Fix largefile support on older NetBSD systems and OpenBSD by adding
1586 define for TELL64.
1587
1588
1589Tools and other miscellany
1590
1591- ftpmirror: Call to main() is wrapped in if __name__ == "__main__".
1592
1593- freeze: The modulefinder now works with 2.0 opcodes.
1594
Tim Petersa3a3a032000-11-30 05:22:44 +00001595- IDLE:
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001596 Move hackery of sys.argv until after the Tk instance has been
1597 created, which allows the application-specific Tkinter
1598 initialization to be executed if present; also pass an explicit
1599 className parameter to the Tk() constructor.
Fred Drake64bb3802000-09-26 16:21:35 +00001600
Jeremy Hylton1b618592000-09-26 05:32:36 +00001601
1602What's new in 2.0 beta 1?
1603=========================
1604
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001605Source Incompatibilities
1606------------------------
1607
1608None. Note that 1.6 introduced several incompatibilities with 1.5.2,
1609such as single-argument append(), connect() and bind(), and changes to
1610str(long) and repr(float).
1611
1612
1613Binary Incompatibilities
1614------------------------
1615
1616- Third party extensions built for Python 1.5.x or 1.6 cannot be used
1617with Python 2.0; these extensions will have to be rebuilt for Python
16182.0.
1619
1620- On Windows, attempting to import a third party extension built for
1621Python 1.5.x or 1.6 results in an immediate crash; there's not much we
1622can do about this. Check your PYTHONPATH environment variable!
1623
1624- Python bytecode files (*.pyc and *.pyo) are not compatible between
1625releases.
1626
1627
1628Overview of Changes Since 1.6
1629-----------------------------
1630
1631There are many new modules (including brand new XML support through
1632the xml package, and i18n support through the gettext module); a list
1633of all new modules is included below. Lots of bugs have been fixed.
1634
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001635The process for making major new changes to the language has changed
1636since Python 1.6. Enhancements must now be documented by a Python
1637Enhancement Proposal (PEP) before they can be accepted.
1638
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001639There are several important syntax enhancements, described in more
1640detail below:
1641
1642 - Augmented assignment, e.g. x += 1
1643
1644 - List comprehensions, e.g. [x**2 for x in range(10)]
1645
1646 - Extended import statement, e.g. import Module as Name
1647
1648 - Extended print statement, e.g. print >> file, "Hello"
1649
1650Other important changes:
1651
1652 - Optional collection of cyclical garbage
1653
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001654Python Enhancement Proposal (PEP)
1655---------------------------------
1656
1657PEP stands for Python Enhancement Proposal. A PEP is a design
1658document providing information to the Python community, or describing
1659a new feature for Python. The PEP should provide a concise technical
1660specification of the feature and a rationale for the feature.
1661
1662We intend PEPs to be the primary mechanisms for proposing new
1663features, for collecting community input on an issue, and for
1664documenting the design decisions that have gone into Python. The PEP
1665author is responsible for building consensus within the community and
1666documenting dissenting opinions.
1667
1668The PEPs are available at http://python.sourceforge.net/peps/.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001669
1670Augmented Assignment
1671--------------------
1672
1673This must have been the most-requested feature of the past years!
1674Eleven new assignment operators were added:
1675
Guido van Rossume905e952000-09-05 12:42:46 +00001676 += -= *= /= %= **= <<= >>= &= ^= |=
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001677
1678For example,
1679
1680 A += B
1681
1682is similar to
1683
1684 A = A + B
1685
1686except that A is evaluated only once (relevant when A is something
1687like dict[index].attr).
1688
1689However, if A is a mutable object, A may be modified in place. Thus,
1690if A is a number or a string, A += B has the same effect as A = A+B
1691(except A is only evaluated once); but if a is a list, A += B has the
1692same effect as A.extend(B)!
1693
1694Classes and built-in object types can override the new operators in
1695order to implement the in-place behavior; the not-in-place behavior is
1696used automatically as a fallback when an object doesn't implement the
1697in-place behavior. For classes, the method name is derived from the
1698method name for the corresponding not-in-place operator by inserting
1699an 'i' in front of the name, e.g. __iadd__ implements in-place
1700__add__.
1701
1702Augmented assignment was implemented by Thomas Wouters.
1703
1704
1705List Comprehensions
1706-------------------
1707
1708This is a flexible new notation for lists whose elements are computed
1709from another list (or lists). The simplest form is:
1710
1711 [<expression> for <variable> in <sequence>]
1712
Guido van Rossum56db0952000-09-06 23:34:25 +00001713For example, [i**2 for i in range(4)] yields the list [0, 1, 4, 9].
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001714This is more efficient than a for loop with a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001715
1716You can also add a condition:
1717
1718 [<expression> for <variable> in <sequence> if <condition>]
1719
1720For example, [w for w in words if w == w.lower()] would yield the list
1721of words that contain no uppercase characters. This is more efficient
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001722than a for loop with an if statement and a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001723
1724You can also have nested for loops and more than one 'if' clause. For
1725example, here's a function that flattens a sequence of sequences::
1726
1727 def flatten(seq):
1728 return [x for subseq in seq for x in subseq]
1729
1730 flatten([[0], [1,2,3], [4,5], [6,7,8,9], []])
1731
1732This prints
1733
1734 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
1735
1736List comprehensions originated as a patch set from Greg Ewing; Skip
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001737Montanaro and Thomas Wouters also contributed. Described by PEP 202.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001738
1739
1740Extended Import Statement
1741-------------------------
1742
1743Many people have asked for a way to import a module under a different
1744name. This can be accomplished like this:
1745
1746 import foo
1747 bar = foo
1748 del foo
1749
1750but this common idiom gets old quickly. A simple extension of the
1751import statement now allows this to be written as follows:
1752
1753 import foo as bar
1754
1755There's also a variant for 'from ... import':
1756
1757 from foo import bar as spam
1758
1759This also works with packages; e.g. you can write this:
1760
1761 import test.regrtest as regrtest
1762
1763Note that 'as' is not a new keyword -- it is recognized only in this
1764context (this is only possible because the syntax for the import
1765statement doesn't involve expressions).
1766
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001767Implemented by Thomas Wouters. Described by PEP 221.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001768
1769
1770Extended Print Statement
1771------------------------
1772
1773Easily the most controversial new feature, this extension to the print
1774statement adds an option to make the output go to a different file
1775than the default sys.stdout.
1776
1777For example, to write an error message to sys.stderr, you can now
1778write:
1779
1780 print >> sys.stderr, "Error: bad dog!"
1781
1782As a special feature, if the expression used to indicate the file
Fred Drake45888ff2000-09-29 17:09:11 +00001783evaluates to None, the current value of sys.stdout is used. Thus:
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001784
1785 print >> None, "Hello world"
1786
1787is equivalent to
1788
1789 print "Hello world"
1790
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001791Design and implementation by Barry Warsaw. Described by PEP 214.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001792
1793
1794Optional Collection of Cyclical Garbage
1795---------------------------------------
1796
1797Python is now equipped with a garbage collector that can hunt down
1798cyclical references between Python objects. It's no replacement for
1799reference counting; in fact, it depends on the reference counts being
1800correct, and decides that a set of objects belong to a cycle if all
1801their reference counts can be accounted for from their references to
1802each other. This devious scheme was first proposed by Eric Tiedemann,
1803and brought to implementation by Neil Schemenauer.
1804
1805There's a module "gc" that lets you control some parameters of the
1806garbage collection. There's also an option to the configure script
1807that lets you enable or disable the garbage collection. In 2.0b1,
1808it's on by default, so that we (hopefully) can collect decent user
1809experience with this new feature. There are some questions about its
Fred Drake9f11cf82000-09-29 17:54:40 +00001810performance. If it proves to be too much of a problem, we'll turn it
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001811off by default in the final 2.0 release.
1812
1813
1814Smaller Changes
1815---------------
1816
1817A new function zip() was added. zip(seq1, seq2, ...) is equivalent to
1818map(None, seq1, seq2, ...) when the sequences have the same length;
1819i.e. zip([1,2,3], [10,20,30]) returns [(1,10), (2,20), (3,30)]. When
1820the lists are not all the same length, the shortest list wins:
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001821zip([1,2,3], [10,20]) returns [(1,10), (2,20)]. See PEP 201.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001822
1823sys.version_info is a tuple (major, minor, micro, level, serial).
1824
1825Dictionaries have an odd new method, setdefault(key, default).
1826dict.setdefault(key, default) returns dict[key] if it exists; if not,
1827it sets dict[key] to default and returns that value. Thus:
1828
1829 dict.setdefault(key, []).append(item)
1830
1831does the same work as this common idiom:
1832
1833 if not dict.has_key(key):
1834 dict[key] = []
1835 dict[key].append(item)
1836
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001837There are two new variants of SyntaxError that are raised for
1838indentation-related errors: IndentationError and TabError.
1839
1840Changed \x to consume exactly two hex digits; see PEP 223. Added \U
1841escape that consumes exactly eight hex digits.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001842
1843The limits on the size of expressions and file in Python source code
1844have been raised from 2**16 to 2**32. Previous versions of Python
1845were limited because the maximum argument size the Python VM accepted
1846was 2**16. This limited the size of object constructor expressions,
1847e.g. [1,2,3] or {'a':1, 'b':2}, and the size of source files. This
1848limit was raised thanks to a patch by Charles Waldman that effectively
1849fixes the problem. It is now much more likely that you will be
1850limited by available memory than by an arbitrary limit in Python.
1851
1852The interpreter's maximum recursion depth can be modified by Python
1853programs using sys.getrecursionlimit and sys.setrecursionlimit. This
1854limit is the maximum number of recursive calls that can be made by
1855Python code. The limit exists to prevent infinite recursion from
1856overflowing the C stack and causing a core dump. The default value is
18571000. The maximum safe value for a particular platform can be found
1858by running Misc/find_recursionlimit.py.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001859
1860New Modules and Packages
1861------------------------
1862
1863atexit - for registering functions to be called when Python exits.
1864
1865imputil - Greg Stein's alternative API for writing custom import
1866hooks.
1867
1868pyexpat - an interface to the Expat XML parser, contributed by Paul
1869Prescod.
1870
1871xml - a new package with XML support code organized (so far) in three
1872subpackages: xml.dom, xml.sax, and xml.parsers. Describing these
1873would fill a volume. There's a special feature whereby a
1874user-installed package named _xmlplus overrides the standard
1875xmlpackage; this is intended to give the XML SIG a hook to distribute
1876backwards-compatible updates to the standard xml package.
1877
1878webbrowser - a platform-independent API to launch a web browser.
1879
1880
Guido van Rossume905e952000-09-05 12:42:46 +00001881Changed Modules
1882---------------
1883
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001884array -- new methods for array objects: count, extend, index, pop, and
1885remove
1886
1887binascii -- new functions b2a_hex and a2b_hex that convert between
1888binary data and its hex representation
1889
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001890calendar -- Many new functions that support features including control
1891over which day of the week is the first day, returning strings instead
1892of printing them. Also new symbolic constants for days of week,
1893e.g. MONDAY, ..., SUNDAY.
1894
1895cgi -- FieldStorage objects have a getvalue method that works like a
1896dictionary's get method and returns the value attribute of the object.
1897
1898ConfigParser -- The parser object has new methods has_option,
1899remove_section, remove_option, set, and write. They allow the module
1900to be used for writing config files as well as reading them.
1901
1902ftplib -- ntransfercmd(), transfercmd(), and retrbinary() all now
Guido van Rossume905e952000-09-05 12:42:46 +00001903optionally support the RFC 959 REST command.
1904
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001905gzip -- readline and readlines now accept optional size arguments
Guido van Rossume905e952000-09-05 12:42:46 +00001906
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001907httplib -- New interfaces and support for HTTP/1.1 by Greg Stein. See
1908the module doc strings for details.
Guido van Rossum830ca2a2000-09-05 15:34:16 +00001909
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001910locale -- implement getdefaultlocale for Win32 and Macintosh
1911
1912marshal -- no longer dumps core when marshaling deeply nested or
1913recursive data structures
1914
1915os -- new functions isatty, seteuid, setegid, setreuid, setregid
1916
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001917os/popen2 -- popen2/popen3/popen4 support under Windows. popen2/popen3
1918support under Unix.
1919
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001920os/pty -- support for openpty and forkpty
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001921
1922os.path -- fix semantics of os.path.commonprefix
1923
1924smtplib -- support for sending very long messages
1925
1926socket -- new function getfqdn()
1927
1928readline -- new functions to read, write and truncate history files.
1929The readline section of the library reference manual contains an
1930example.
1931
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001932select -- add interface to poll system call
1933
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001934shutil -- new copyfileobj function
1935
1936SimpleHTTPServer, CGIHTTPServer -- Fix problems with buffering in the
1937HTTP server.
1938
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001939Tkinter -- optimization of function flatten
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001940
1941urllib -- scans environment variables for proxy configuration,
Tim Peters8b092332000-09-05 20:15:25 +00001942e.g. http_proxy.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001943
1944whichdb -- recognizes dumbdbm format
Guido van Rossume905e952000-09-05 12:42:46 +00001945
1946
1947Obsolete Modules
1948----------------
1949
1950None. However note that 1.6 made a whole slew of modules obsolete:
1951stdwin, soundex, cml, cmpcache, dircache, dump, find, grep, packmail,
1952poly, zmod, strop, util, whatsound.
1953
1954
1955Changed, New, Obsolete Tools
1956----------------------------
1957
Tim Peters8b092332000-09-05 20:15:25 +00001958None.
Guido van Rossume905e952000-09-05 12:42:46 +00001959
1960
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001961C-level Changes
1962---------------
1963
1964Several cleanup jobs were carried out throughout the source code.
1965
1966All C code was converted to ANSI C; we got rid of all uses of the
1967Py_PROTO() macro, which makes the header files a lot more readable.
1968
1969Most of the portability hacks were moved to a new header file,
1970pyport.h; several other new header files were added and some old
1971header files were removed, in an attempt to create a more rational set
1972of header files. (Few of these ever need to be included explicitly;
1973they are all included by Python.h.)
1974
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001975Trent Mick ensured portability to 64-bit platforms, under both Linux
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001976and Win64, especially for the new Intel Itanium processor. Mick also
1977added large file support for Linux64 and Win64.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001978
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001979The C APIs to return an object's size have been update to consistently
1980use the form PyXXX_Size, e.g. PySequence_Size and PyDict_Size. In
1981previous versions, the abstract interfaces used PyXXX_Length and the
1982concrete interfaces used PyXXX_Size. The old names,
1983e.g. PyObject_Length, are still available for backwards compatibility
1984at the API level, but are deprecated.
1985
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001986The PyOS_CheckStack function has been implemented on Windows by
1987Fredrik Lundh. It prevents Python from failing with a stack overflow
1988on Windows.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001989
1990The GC changes resulted in creation of two new slots on object,
1991tp_traverse and tp_clear. The augmented assignment changes result in
Guido van Rossum4338a282000-09-06 13:02:08 +00001992the creation of a new slot for each in-place operator.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001993
1994The GC API creates new requirements for container types implemented in
Guido van Rossum4338a282000-09-06 13:02:08 +00001995C extension modules. See Include/objimpl.h for details.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001996
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001997PyErr_Format has been updated to automatically calculate the size of
1998the buffer needed to hold the formatted result string. This change
1999prevents crashes caused by programmer error.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002000
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002001New C API calls: PyObject_AsFileDescriptor, PyErr_WriteUnraisable.
Guido van Rossume905e952000-09-05 12:42:46 +00002002
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002003PyRun_AnyFileEx, PyRun_SimpleFileEx, PyRun_FileEx -- New functions
2004that are the same as their non-Ex counterparts except they take an
2005extra flag argument that tells them to close the file when done.
2006
2007XXX There were other API changes that should be fleshed out here.
Guido van Rossumab9d6f01998-08-10 22:01:13 +00002008
Tim Peters8b092332000-09-05 20:15:25 +00002009
2010Windows Changes
2011---------------
2012
2013New popen2/popen3/peopen4 in os module (see Changed Modules above).
2014
2015os.popen is much more usable on Windows 95 and 98. See Microsoft
2016Knowledge Base article Q150956. The Win9x workaround described there
2017is implemented by the new w9xpopen.exe helper in the root of your
2018Python installation. Note that Python uses this internally; it is not
2019a standalone program.
2020
2021Administrator privileges are no longer required to install Python
2022on Windows NT or Windows 2000. If you have administrator privileges,
2023Python's registry info will be written under HKEY_LOCAL_MACHINE.
2024Otherwise the installer backs off to writing Python's registry info
Guido van Rossum4338a282000-09-06 13:02:08 +00002025under HKEY_CURRENT_USER. The latter is sufficient for all "normal"
Tim Peters8b092332000-09-05 20:15:25 +00002026uses of Python, but will prevent some advanced uses from working
2027(for example, running a Python script as an NT service, or possibly
2028from CGI).
2029
2030[This was new in 1.6] The installer no longer runs a separate Tcl/Tk
2031installer; instead, it installs the needed Tcl/Tk files directly in the
2032Python directory. If you already have a Tcl/Tk installation, this
2033wastes some disk space (about 4 Megs) but avoids problems with
2034conflicting Tcl/Tk installations, and makes it much easier for Python
2035to ensure that Tcl/Tk can find all its files.
2036
2037[This was new in 1.6] The Windows installer now installs by default in
2038\Python20\ on the default volume, instead of \Program Files\Python-2.0\.
2039
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002040
2041Updates to the changes between 1.5.2 and 1.6
2042--------------------------------------------
2043
2044The 1.6 NEWS file can't be changed after the release is done, so here
2045is some late-breaking news:
2046
2047New APIs in locale.py: normalize(), getdefaultlocale(), resetlocale(),
2048and changes to getlocale() and setlocale().
2049
2050The new module is now enabled per default.
2051
2052It is not true that the encodings codecs cannot be used for normal
2053strings: the string.encode() (which is also present on 8-bit strings
2054!) allows using them for 8-bit strings too, e.g. to convert files from
2055cp1252 (Windows) to latin-1 or vice-versa.
2056
2057Japanese codecs are available from Tamito KAJIYAMA:
2058http://pseudo.grad.sccs.chukyo-u.ac.jp/~kajiyama/python/
2059
2060
Guido van Rossumab9d6f01998-08-10 22:01:13 +00002061======================================================================