blob: 44cf065d2f933e52d3d75dd681037117076dfc03 [file] [log] [blame]
Tim Petersf553f892001-05-01 20:45:31 +00001What's New in Python 2.2a0?
2===========================
3
4Core
Tim Petersa814db52001-05-14 07:05:58 +00005
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00006- Strings now have a new method .decode() to complement the already
7 existing .encode() method. These two methods provide direct access
8 to the corresponding decoders and encoders of the registered codecs.
9
10 To enhance the usability of the .encode() method, the special
11 casing of Unicode object return values was dropped (Unicode objects
12 were auto-magically converted to string using the default encoding).
13
14 Both methods will now return whatever the codec in charge of the
15 requested encoding returns as object, e.g. Unicode codecs will
16 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
17 will return u"äöü"). This enables codec writer to create codecs
18 for various simple to use conversions.
19
20 New codecs were added to demonstrate these new features (the .encode()
21 and .decode() columns indicate the type of the returned objects):
22
23 Name | .encode() | .decode() | Description
24 ----------------------------------------------------------------------
25 uu | string | string | UU codec (e.g. for email)
26 base64 | string | string | base64 codec
27 zlib | string | string | zlib compression
28 hex | string | string | 2-byte hex codec
29 rot-13 | string | Unicode | ROT-13 Unicode charmap codec
30
Mark Hammond2a0af792001-05-14 03:09:36 +000031- Some operating systems now support the concept of a default Unicode
32 encoding for file system operations. Notably, Windows supports 'mbcs'
33 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +000034 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +000035 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +000036
37 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +000038 functions that return filenames (such as os.listdir()) to return Python
39 string objects pre-encoded using the default file system encoding for
40 the platform. As this encoding is likely to be different from Python's
41 default encoding, converting this name to a Unicode object before passing
42 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +000043 would attempt to use its default encoding (generally ASCII) rather than
44 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +000045
Tim Petersa814db52001-05-14 07:05:58 +000046 In general, this change simply removes surprises when working with
47 Unicode and the file system, making these operations work as you expect,
48 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +000049 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +000050
Tim Peters61dff2b2001-05-08 15:43:37 +000051- Float (and complex) literals in source code were evaluated to full
52 precision only when running from a .py file; the same code loaded from a
53 .pyc (or .pyo) file could suffer numeric differences starting at about the
54 12th significant decimal digit. For example, on a machine with IEEE-754
55 floating arithmetic,
56
57 x = 9007199254740992.0
58 print long(x)
59
60 printed 9007199254740992 if run directly from .py, but 9007199254740000
61 if from a compiled (.pyc or .pyo) file. This was due to marshal using
62 str(float) instead of repr(float) when building code objects. marshal
63 now uses repr(float) instead, which should reproduce floats to full
64 machine precision (assuming the platform C float<->string I/O conversion
65 functions are of good quality).
66
67 This may cause floating-point results to change in some cases, and
68 usually for the better, but may also cause numerically unstable
69 algorithms to break.
70
Tim Peters2f228e72001-05-13 00:19:31 +000071- The implementation of dicts suffers fewer collisions, which has speed
72 benefits. However, the order in which dict entries appear in dict.keys(),
73 dict.values() and dict.items() may differ from previous releases for a
74 given dict. Nothing is defined about this order, so no program should
75 rely on it. Nevertheless, it's easy to write test cases that rely on the
76 order by accident, typically because of printing the str() or repr() of a
77 dict to an "expected results" file. See Lib/test/test_support.py's new
78 sortdict(dict) function for a simple way to display a dict in sorted
79 order.
80
Guido van Rossum10315822001-05-01 20:54:30 +000081- Dictionary objects now support the "in" operator: "x in dict" means
82 the same as dict.has_key(x).
83
84- Iterators were added; this is a generalized way of providing values
85 to a for loop. See PEP 234. There's a new built-in function iter()
86 to return an iterator. There's a new protocol to get the next value
87 from an iterator using the next() method (in Python) or the
88 tp_iternext slot (in C). There's a new protocol to get iterators
89 using the __iter__() method (in Python) or the tp_iter slot (in C).
90 Iterating (i.e. a for loop) over a dictionary generates its keys.
91 Iterating over a file generates its lines.
92
Tim Petersf553f892001-05-01 20:45:31 +000093- The following functions were generalized to work nicely with iterator
94 arguments:
Tim Peterse63415e2001-05-08 04:38:29 +000095 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +000096 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
97 max(), min()
Tim Petersde9725f2001-05-05 10:06:17 +000098 .join() method of strings
Tim Peters75f8e352001-05-05 11:33:43 +000099 'x in y' and 'x not in y' (PySequence_Contains() in C API)
100 operator.countOf() (PySequence_Count() in C API)
Tim Peters75f8e352001-05-05 11:33:43 +0000101
Tim Petersd85e1022001-05-11 21:51:48 +0000102- Accessing module attributes is significantly faster (for example,
103 random.random or os.path or yourPythonModule.yourAttribute).
104
Tim Peterse63415e2001-05-08 04:38:29 +0000105- Comparing dictionary objects via == and != is faster, and now works even
106 if the keys and values don't support comparisons other than ==.
107
Tim Peters95bf9392001-05-10 08:32:44 +0000108- Comparing dictionaries in ways other than == and != is slower: there were
109 insecurities in the dict comparison implementation that could cause Python
110 to crash if the element comparison routines for the dict keys and/or
111 values mutated the dicts. Making the code bulletproof slowed it down.
112
Tim Petersa814db52001-05-14 07:05:58 +0000113Library
114
Guido van Rossum2e0a6542001-05-15 02:14:44 +0000115- strop is now *really* obsolete (this was announced before with 1.6),
116 and issues DeprecationWarning when used (except for the four items
117 that are still imported into string.py).
118
Tim Petersa814db52001-05-14 07:05:58 +0000119- Cookie.py now sorts key+value pairs by key in output strings.
120
121- pprint.isrecursive(object) didn't correctly identify recursive objects.
122 Now it does.
123
Tim Peters95b3f782001-05-14 18:39:41 +0000124- pprint functions now much faster for large containers (tuple, list, dict).
125
Tim Petersa814db52001-05-14 07:05:58 +0000126Tests
127
128- New test_mutants.py runs dict comparisons where the key and value
129 comparison operators mutute the dicts randomly during comparison. This
130 rapidly causes Python to crash under earlier releases (not for the faint
131 of heart: it can also cause Win9x to freeze or reboot!).
132
133- New test_pprint.py verfies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +0000134 pprint.isreadable() return sensible results. Also verifies that simple
135 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +0000136
Tim Peters58e0a8c2001-05-14 22:32:33 +0000137New platforms
138
139- Python should compile and run out of the box using the Borland C
140 compiler (under Windows), thanks to Stephen Hansen.
Tim Petersf553f892001-05-01 20:45:31 +0000141
Guido van Rossumffe13be2001-04-16 18:46:45 +0000142What's New in Python 2.1 (final)?
143=================================
144
145We only changed a few things since the last release candidate, all in
146Python library code:
147
148- A bug in the locale module was fixed that affected locales which
149 define no grouping for numeric formatting.
150
151- A few bugs in the weakref module's implementations of weak
152 dictionaries (WeakValueDictionary and WeakKeyDictionary) were fixed,
153 and the test suite was updated to check for these bugs.
154
155- An old bug in the os.path.walk() function (introduced in Python
156 2.0!) was fixed: a non-existent file would cause an exception
157 instead of being ignored.
158
159- Fixed a few bugs in the new symtable module found by Neil Norwitz's
160 PyChecker.
161
162
Guido van Rossum5b08f132001-04-16 02:05:23 +0000163What's New in Python 2.1c2?
164===========================
Barry Warsaw11e89c72001-04-11 20:37:57 +0000165
Guido van Rossum5b08f132001-04-16 02:05:23 +0000166A flurry of small changes, and one showstopper fixed in the nick of
167time made it necessary to release another release candidate. The list
168here is the *complete* list of patches (except version updates):
Guido van Rossum4fb60362001-04-13 00:46:14 +0000169
Guido van Rossum5b08f132001-04-16 02:05:23 +0000170Core
Guido van Rossum4fb60362001-04-13 00:46:14 +0000171
Guido van Rossum5b08f132001-04-16 02:05:23 +0000172- Tim discovered a nasty bug in the dictionary code, caused by
173 PyDict_Next() calling dict_resize(), and the GC code's use of
174 PyDict_Next() violating an assumption in dict_items(). This was
175 fixed with considerable amounts of band-aid, but the net effect is a
176 saner and more robust implementation.
177
178- Made a bunch of symbols static that were accidentally global.
179
180Build and Ports
181
182- The setup.py script didn't check for a new enough version of zlib
183 (1.1.3 is needed). Now it does.
184
185- Changed "make clean" target to also remove shared libraries.
186
187- Added a more general warning about the SGI Irix optimizer to README.
188
189Library
190
191- Fix a bug in urllib.basejoin("http://host", "../file.html") which
192 omitted the slash between host and file.html.
193
194- The mailbox module's _Mailbox class contained a completely broken
195 and undocumented seek() method. Ripped it out.
196
197- Fixed a bunch of typos in various library modules (urllib2, smtpd,
198 sgmllib, netrc, chunk) found by Neil Norwitz's PyChecker.
199
200- Fixed a few last-minute bugs in unittest.
201
202Extensions
203
204- Reverted the patch to the OpenSSL code in socketmodule.c to support
205 RAND_status() and the EGD, and the subsequent patch that tried to
206 fix it for pre-0.9.5 versions; the problem with the patch is that on
207 some systems it issues a warning whenever socket is imported, and
208 that's unacceptable.
209
210Tests
211
212- Fixed the pickle tests to work with "import test.test_pickle".
213
214- Tweaked test_locale.py to actually run the test Windows.
215
216- In distutils/archive_util.py, call zipfile.ZipFile() with mode "w",
217 not "wb" (which is not a valid mode at all).
218
219- Fix pstats browser crashes. Import readline if it exists to make
220 the user interface nicer.
221
222- Add "import thread" to the top of test modules that import the
223 threading module (test_asynchat and test_threadedtempfile). This
224 prevents test failures caused by a broken threading module resulting
225 from a previously caught failed import.
226
227- Changed test_asynchat.py to set the SO_REUSEADDR option; this was
228 needed on some platforms (e.g. Solaris 8) when the tests are run
229 twice in succession.
230
231- Skip rather than fail test_sunaudiodev if no audio device is found.
232
233
234What's New in Python 2.1c1?
235===========================
236
237This list was significantly updated when 2.1c2 was released; the 2.1c1
238release didn't mention most changes that were actually part of 2.1c1:
239
240Legal
241
242- Copyright was assigned to the Python Software Foundation (PSF) and a
243 PSF license (very similar to the CNRI license) was added.
244
245- The CNRI copyright notice was updated to include 2001.
246
247Core
Barry Warsaw11e89c72001-04-11 20:37:57 +0000248
Guido van Rossumc9932722001-04-12 02:31:27 +0000249- After a public outcry, assignment to __debug__ is no longer illegal;
250 instead, a warning is issued. It will become illegal in 2.2.
251
Guido van Rossum5b08f132001-04-16 02:05:23 +0000252- Fixed a core dump with "%#x" % 0, and changed the semantics so that
253 "%#x" now always prepends "0x", even if the value is zero.
254
255- Fixed some nits in the bytecode compiler.
256
257- Fixed core dumps when calling certain kinds of non-functions.
258
259- Fixed various core dumps caused by reference count bugs.
260
261Build and Ports
262
263- Use INSTALL_SCRIPT to install script files.
264
Guido van Rossum34d37dc2001-04-11 21:03:32 +0000265- New port: SCO Unixware 7, by Billy G. Allie.
266
Guido van Rossum5b08f132001-04-16 02:05:23 +0000267- Updated RISCOS port.
268
269- Updated BeOS port and notes.
270
271- Various other porting problems resolved.
272
273Library
274
275- The TERMIOS and SOCKET modules are now truly obsolete and
276 unnecessary. Their symbols are incorporated in the termios and
277 socket modules.
278
279- Fixed some 64-bit bugs in pickle, cPickle, and struct, and added
280 better tests for pickling.
281
282- threading: make Condition.wait() robust against KeyboardInterrupt.
283
284- zipfile: add support to zipfile to support opening an archive
285 represented by an open file rather than a file name. Fix bug where
286 the archive was not properly closed. Fixed a bug in this bugfix
287 where flush() was called for a read-only file.
288
289- imputil: added an uninstall() method to the ImportManager.
290
291- Canvas: fixed bugs in lower() and tkraise() methods.
292
293- SocketServer: API change (added overridable close_request() method)
294 so that the TCP server can explicitly close the request.
295
296- pstats: Eric Raymond added a simple interactive statistics browser,
297 invoked when the module is run as a script.
298
299- locale: fixed a problem in format().
300
301- webbrowser: made it work when the BROWSER environment variable has a
302 value like "/usr/bin/netscape". Made it auto-detect Konqueror for
303 KDE 2. Fixed some other nits.
304
305- unittest: changes to allow using a different exception than
306 AssertionError, and added a few more function aliases. Some other
307 small changes.
308
309- urllib, urllib2: fixed redirect problems and a coupleof other nits.
310
311- asynchat: fixed a critical bug in asynchat that slipped through the
312 2.1b2 release. Fixed another rare bug.
313
314- Fix some unqualified except: clauses (always a bad code example).
315
316XML
317
318- pyexpat: new API get_version_string().
319
320- Fixed some minidom bugs.
321
322Extensions
323
324- Fixed a core dump in _weakref. Removed the weakref.mapping()
325 function (it adds nothing to the API).
326
327- Rationalized the use of header files in the readline module, to make
328 it compile (albeit with some warnings) with the very recent readline
329 4.2, without breaking for earlier versions.
330
331- Hopefully fixed a buffering problem in linuxaudiodev.
332
333- Attempted a fix to make the OpenSSL support in the socket module
334 work again with pre-0.9.5 versions of OpenSSL.
335
336Tests
337
338- Added a test case for asynchat and asyncore.
339
340- Removed coupling between tests where one test failing could break
341 another.
342
343Tools
344
345- Ping added an interactive help browser to pydoc, fixed some nits
346 in the rest of the pydoc code, and added some features to his
347 inspect module.
348
349- An updated python-mode.el version 4.1 which integrates Ken
350 Manheimer's pdbtrack.el. This makes debugging Python code via pdb
351 much nicer in XEmacs and Emacs. When stepping through your program
352 with pdb, in either the shell window or the *Python* window, the
353 source file and line will be tracked by an arrow. Very cool!
354
355- IDLE: syntax warnings in interactive mode are changed into errors.
356
357- Some improvements to Tools/webchecker (ignore some more URL types,
Tim Peters0e57abf2001-05-02 07:39:38 +0000358 follow some more links).
Guido van Rossum5b08f132001-04-16 02:05:23 +0000359
360- Brought the Tools/compiler package up to date.
Guido van Rossum34d37dc2001-04-11 21:03:32 +0000361
Barry Warsaw11e89c72001-04-11 20:37:57 +0000362
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000363What's New in Python 2.1 beta 2?
364================================
365
Guido van Rossum053ae352001-03-22 14:17:21 +0000366(Unlisted are many fixed bugs, more documentation, etc.)
367
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000368Core language, builtins, and interpreter
369
Guido van Rossum053ae352001-03-22 14:17:21 +0000370- The nested scopes work (enabled by "from __future__ import
371 nested_scopes") is completed; in particular, the future now extends
372 into code executed through exec, eval() and execfile(), and into the
373 interactive interpreter.
374
375- When calling a base class method (e.g. BaseClass.__init__(self)),
376 this is now allowed even if self is not strictly spoken a class
377 instance (e.g. when using metaclasses or the Don Beaudry hook).
378
379- Slice objects are now comparable but not hashable; this prevents
380 dict[:] from being accepted but meaningless.
381
382- Complex division is now calculated using less braindead algorithms.
383 This doesn't change semantics except it's more likely to give useful
384 results in extreme cases. Complex repr() now uses full precision
385 like float repr().
386
387- sgmllib.py now calls handle_decl() for simple <!...> declarations.
388
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000389- It is illegal to assign to the name __debug__, which is set when the
390 interpreter starts. It is effectively a compile-time constant.
391
392- A warning will be issued if a global statement for a variable
393 follows a use or assignment of that variable.
394
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000395Standard library
396
Guido van Rossum053ae352001-03-22 14:17:21 +0000397- unittest.py, a unit testing framework by Steve Purcell (PyUNIT,
398 inspired by JUnit), is now part of the standard library. You now
399 have a choice of two testing frameworks: unittest requires you to
400 write testcases as separate code, doctest gathers them from
401 docstrings. Both approaches have their advantages and
402 disadvantages.
403
404- A new module Tix was added, which wraps the Tix extension library
405 for Tk. With that module, it is not necessary to statically link
406 Tix with _tkinter, since Tix will be loaded with Tcl's "package
407 require" command. See Demo/tix/.
408
409- tzparse.py is now obsolete.
410
411- In gzip.py, the seek() and tell() methods are removed -- they were
412 non-functional anyway, and it's better if callers can test for their
413 existence with hasattr().
414
415Python/C API
416
417- PyDict_Next(): it is now safe to call PyDict_SetItem() with a key
418 that's already in the dictionary during a PyDict_Next() iteration.
419 This used to fail occasionally when a dictionary resize operation
420 could be triggered that would rehash all the keys. All other
421 modifications to the dictionary are still off-limits during a
422 PyDict_Next() iteration!
423
424- New extended APIs related to passing compiler variables around.
425
426- New abstract APIs PyObject_IsInstance(), PyObject_IsSubclass()
427 implement isinstance() and issubclass().
428
429- Py_BuildValue() now has a "D" conversion to create a Python complex
430 number from a Py_complex C value.
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000431
Fred Drake4e262a92001-03-22 18:26:47 +0000432- Extensions types which support weak references must now set the
433 field allocated for the weak reference machinery to NULL themselves;
434 this is done to avoid the cost of checking each object for having a
435 weakly referencable type in PyObject_INIT(), since most types are
436 not weakly referencable.
437
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000438- PyFrame_FastToLocals() and PyFrame_LocalsToFast() copy bindings for
439 free variables and cell variables to and from the frame's f_locals.
440
441- Variants of several functions defined in pythonrun.h have been added
442 to support the nested_scopes future statement. The variants all end
443 in Flags and take an extra argument, a PyCompilerFlags *; examples:
444 PyRun_AnyFileExFlags(), PyRun_InteractiveLoopFlags(). These
445 variants may be removed in Python 2.2, when nested scopes are
Tim Peters0e57abf2001-05-02 07:39:38 +0000446 mandatory.
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000447
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000448Distutils
449
450- the sdist command now writes a PKG-INFO file, as described in PEP 241,
451 into the release tree.
452
Tim Peters0e57abf2001-05-02 07:39:38 +0000453- several enhancements to the bdist_wininst command from Thomas Heller
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000454 (an uninstaller, more customization of the installer's display)
455
456- from Jack Jansen: added Mac-specific code to generate a dialog for
457 users to specify the command-line (because providing a command-line with
Tim Peters0e57abf2001-05-02 07:39:38 +0000458 MacPython is awkward). Jack also made various fixes for the Mac
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000459 and the Metrowerks compiler.
Tim Peters0e57abf2001-05-02 07:39:38 +0000460
461- added 'platforms' and 'keywords' to the set of metadata that can be
462 specified for a distribution.
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000463
464- applied patches from Jason Tishler to make the compiler class work with
465 Cygwin.
466
467
Tim Peters2fe289a2001-03-01 22:19:38 +0000468What's New in Python 2.1 beta 1?
469================================
Tim Petersd66595f2001-02-04 03:09:53 +0000470
471Core language, builtins, and interpreter
472
Guido van Rossum9d0fbde2001-03-02 14:00:32 +0000473- Following an outcry from the community about the amount of code
474 broken by the nested scopes feature introduced in 2.1a2, we decided
475 to make this feature optional, and to wait until Python 2.2 (or at
476 least 6 months) to make it standard. The option can be enabled on a
477 per-module basis by adding "from __future__ import nested_scopes" at
478 the beginning of a module (before any other statements, but after
479 comments and an optional docstring). See PEP 236 (Back to the
480 __future__) for a description of the __future__ statement. PEP 227
481 (Statically Nested Scopes) has been updated to reflect this change,
482 and to clarify the semantics in a number of endcases.
483
484- The nested scopes code, when enabled, has been hardened, and most
485 bugs and memory leaks in it have been fixed.
486
487- Compile-time warnings are now generated for a number of conditions
488 that will break or change in meaning when nested scopes are enabled:
489
490 - Using "from...import *" or "exec" without in-clause in a function
491 scope that also defines a lambda or nested function with one or
492 more free (non-local) variables. The presence of the import* or
493 bare exec makes it impossible for the compiler to determine the
494 exact set of local variables in the outer scope, which makes it
495 impossible to determine the bindings for free variables in the
496 inner scope. To avoid the warning about import *, change it into
497 an import of explicitly name object, or move the import* statement
498 to the global scope; to avoid the warning about bare exec, use
499 exec...in... (a good idea anyway -- there's a possibility that
500 bare exec will be deprecated in the future).
501
502 - Use of a global variable in a nested scope with the same name as a
503 local variable in a surrounding scope. This will change in
504 meaning with nested scopes: the name in the inner scope will
505 reference the variable in the outer scope rather than the global
506 of the same name. To avoid the warning, either rename the outer
507 variable, or use a global statement in the inner function.
508
Neil Schemenauera35c6882001-02-27 04:45:05 +0000509- An optional object allocator has been included. This allocator is
510 optimized for Python objects and should be faster and use less memory
511 than the standard system allocator. It is not enabled by default
512 because of possible thread safety problems. The allocator is only
513 protected by the Python interpreter lock and it is possible that some
514 extension modules require a thread safe allocator. The object
515 allocator can be enabled by providing the "--with-pymalloc" option to
516 configure.
517
Tim Petersd66595f2001-02-04 03:09:53 +0000518Standard library
519
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000520- pyexpat now detects the expat version if expat.h defines it. A
521 number of additional handlers are provided, which are only available
522 since expat 1.95. In addition, the methods SetParamEntityParsing and
523 GetInputContext of Parser objects are available with 1.95.x
524 only. Parser objects now provide the ordered_attributes and
525 specified_attributes attributes. A new module expat.model was added,
526 which offers a number of additional constants if 1.95.x is used.
527
528- xml.dom offers the new functions registerDOMImplementation and
529 getDOMImplementation.
530
531- xml.dom.minidom offers a toprettyxml method. A number of DOM
532 conformance issues have been resolved. In particular, Element now
533 has an hasAttributes method, and the handling of namespaces was
534 improved.
535
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +0000536- Ka-Ping Yee contributed two new modules: inspect.py, a module for
537 getting information about live Python code, and pydoc.py, a module
538 for interactively converting docstrings to HTML or text.
539 Tools/scripts/pydoc, which is now automatically installed into
Tim Peters1eff7962001-03-01 02:31:33 +0000540 <prefix>/bin, uses pydoc.py to display documentation; try running
Guido van Rossume3955a82001-03-02 14:05:59 +0000541 "pydoc -h" for instructions. "pydoc -g" pops up a small GUI that
542 lets you browse the module docstrings using a web browser.
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +0000543
Tim Peters1eff7962001-03-01 02:31:33 +0000544- New library module difflib.py, primarily packaging the SequenceMatcher
545 class at the heart of the popular ndiff.py file-comparison tool.
546
547- doctest.py (a framework for verifying Python code examples in docstrings)
548 is now part of the std library.
549
Tim Petersd66595f2001-02-04 03:09:53 +0000550Windows changes
551
Guido van Rossume3955a82001-03-02 14:05:59 +0000552- A new entry in the Start menu, "Module Docs", runs "pydoc -g" -- a
553 small GUI that lets you browse the module docstrings using your
554 default web browser.
555
Tim Peters1eff7962001-03-01 02:31:33 +0000556- Import is now case-sensitive. PEP 235 (Import on Case-Insensitive
557 Platforms) is implemented. See
558
559 http://python.sourceforge.net/peps/pep-0235.html
560
561 for full details, especially the "Current Lower-Left Semantics" section.
562 The new Windows import rules are simpler than before:
563
564 A. If the PYTHONCASEOK environment variable exists, same as
565 before: silently accept the first case-insensitive match of any
566 kind; raise ImportError if none found.
567
568 B. Else search sys.path for the first case-sensitive match; raise
569 ImportError if none found.
570
571 The same rules have been implented on other platforms with case-
572 insensitive but case-preserving filesystems too (including Cygwin, and
573 several flavors of Macintosh operating systems).
Tim Petersd66595f2001-02-04 03:09:53 +0000574
Tim Peters25a9ce32001-02-19 07:06:36 +0000575- winsound module: Under Win9x, winsound.Beep() now attempts to simulate
576 what it's supposed to do (and does do under NT and 2000) via direct
577 port manipulation. It's unknown whether this will work on all systems,
Tim Peters1eff7962001-03-01 02:31:33 +0000578 but it does work on my Win98SE systems now and was known to be useless on
Tim Peters25a9ce32001-02-19 07:06:36 +0000579 all Win9x systems before.
580
Tim Peters1eff7962001-03-01 02:31:33 +0000581- Build: Subproject _test (effectively) renamed to _testcapi.
582
Tim Peters2fe289a2001-03-01 22:19:38 +0000583New platforms
584
585- 2.1 should compile and run out of the box under MacOS X, even using HFS+.
586 Thanks to Steven Majewski!
587
588- 2.1 should compile and run out of the box on Cygwin. Thanks to Jason
589 Tishler!
590
Guido van Rossum9089b272001-03-02 06:49:50 +0000591- 2.1 contains new files and patches for RISCOS, thanks to Dietmar
592 Schwertberger! See RISCOS/README for more information -- it seems
593 that because of the bizarre filename conventions on RISCOS, no port
594 to that platform is easy. Note that the new variable os.endsep is
595 silently supported in order to make life easier on this platform,
596 but we don't advertise it because it's not worth for most folks to
597 care about RISCOS portability.
598
Tim Peters25a9ce32001-02-19 07:06:36 +0000599
Tim Petersd7b5e882001-01-25 03:36:26 +0000600What's New in Python 2.1 alpha 2?
601=================================
Tim Peters40ead762001-01-27 05:35:26 +0000602
Tim Petersd7b5e882001-01-25 03:36:26 +0000603Core language, builtins, and interpreter
604
Jeremy Hylton4589bd82001-02-01 20:38:45 +0000605- Scopes nest. If a name is used in a function or class, but is not
606 local, the definition in the nearest enclosing function scope will
607 be used. One consequence of this change is that lambda statements
608 could reference variables in the namespaces where the lambda is
609 defined. In some unusual cases, this change will break code.
610
611 In all previous version of Python, names were resolved in exactly
612 three namespaces -- the local namespace, the global namespace, and
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000613 the builtin namespace. According to this old definition, if a
Jeremy Hylton4589bd82001-02-01 20:38:45 +0000614 function A is defined within a function B, the names bound in B are
615 not visible in A. The new rules make names bound in B visible in A,
616 unless A contains a name binding that hides the binding in B.
617
618 Section 4.1 of the reference manual describes the new scoping rules
619 in detail. The test script in Lib/test/test_scope.py demonstrates
620 some of the effects of the change.
621
622 The new rules will cause existing code to break if it defines nested
623 functions where an outer function has local variables with the same
624 name as globals or builtins used by the inner function. Example:
625
626 def munge(str):
627 def helper(x):
628 return str(x)
629 if type(str) != type(''):
630 str = helper(str)
631 return str.strip()
632
633 Under the old rules, the name str in helper() is bound to the
634 builtin function str(). Under the new rules, it will be bound to
635 the argument named str and an error will occur when helper() is
636 called.
637
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000638- The compiler will report a SyntaxError if "from ... import *" occurs
639 in a function or class scope. The language reference has documented
640 that this case is illegal, but the compiler never checked for it.
641 The recent introduction of nested scope makes the meaning of this
642 form of name binding ambiguous. In a future release, the compiler
643 may allow this form when there is no possibility of ambiguity.
644
Tim Peters40ead762001-01-27 05:35:26 +0000645- repr(string) is easier to read, now using hex escapes instead of octal,
646 and using \t, \n and \r instead of \011, \012 and \015 (respectively):
647
648 >>> "\texample \r\n" + chr(0) + chr(255)
649 '\texample \r\n\x00\xff' # in 2.1
650 '\011example \015\012\000\377' # in 2.0
651
Moshe Zadka6af0ce02001-01-29 06:41:00 +0000652- Functions are now compared and hashed by identity, not by value, since
653 the func_code attribute is writable.
654
Fred Drakefb9d7122001-02-01 20:00:40 +0000655- Weak references (PEP 205) have been added. This involves a few
656 changes in the core, an extension module (_weakref), and a Python
657 module (weakref). The weakref module is the public interface. It
658 includes support for "explicit" weak references, proxy objects, and
659 mappings with weakly held values.
660
Jeremy Hylton0072d5a2001-02-01 22:53:15 +0000661- A 'continue' statement can now appear in a try block within the body
662 of a loop. It is still not possible to use continue in a finally
Tim Peters9ea17ac2001-02-02 05:57:15 +0000663 clause.
Jeremy Hylton0072d5a2001-02-01 22:53:15 +0000664
Tim Petersd7b5e882001-01-25 03:36:26 +0000665Standard library
666
Barry Warsaw30dbd142001-01-31 22:14:01 +0000667- mailbox.py now has a new class, PortableUnixMailbox which is
668 identical to UnixMailbox but uses a more portable scheme for
669 determining From_ separators. Also, the constructors for all the
670 classes in this module have a new optional `factory' argument, which
671 is a callable used when new message classes must be instantiated by
672 the next() method.
673
Tim Petersd7b5e882001-01-25 03:36:26 +0000674- random.py is now self-contained, and offers all the functionality of
675 the now-deprecated whrandom.py. See the docs for details. random.py
676 also supports new functions getstate() and setstate(), for saving
Tim Petersd52269b2001-01-25 06:23:18 +0000677 and restoring the internal state of the generator; and jumpahead(n),
678 for quickly forcing the internal state to be the same as if n calls to
679 random() had been made. The latter is particularly useful for multi-
680 threaded programs, creating one instance of the random.Random() class for
681 each thread, then using .jumpahead() to force each instance to use a
682 non-overlapping segment of the full period.
Tim Petersd7b5e882001-01-25 03:36:26 +0000683
Tim Peters0de88fc2001-02-01 04:59:18 +0000684- random.py's seed() function is new. For bit-for-bit compatibility with
685 prior releases, use the whseed function instead. The new seed function
686 addresses two problems: (1) The old function couldn't produce more than
687 about 2**24 distinct internal states; the new one about 2**45 (the best
688 that can be done in the Wichmann-Hill generator). (2) The old function
689 sometimes produced identical internal states when passed distinct
690 integers, and there was no simple way to predict when that would happen;
691 the new one guarantees to produce distinct internal states for all
692 arguments in [0, 27814431486576L).
693
Jeremy Hylton4c4fda02001-02-02 03:29:24 +0000694- The socket module now supports raw packets on Linux. The socket
695 family is AF_PACKET.
696
Tim Peters9ea17ac2001-02-02 05:57:15 +0000697- test_capi.py is a start at running tests of the Python C API. The tests
698 are implemented by the new Modules/_testmodule.c.
699
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000700- A new extension module, _symtable, provides provisional access to the
701 internal symbol table used by the Python compiler. A higher-level
702 interface will be added on top of _symtable in a future release.
703
Andrew M. Kuchlingdebc3522001-02-22 15:53:21 +0000704- Removed the obsolete soundex module.
705
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000706- xml.dom.minidom now uses the standard DOM exceptions. Node supports
707 the isSameNode method; NamedNodeMap the get method.
708
709- xml.sax.expatreader supports the lexical handler property; it
710 generates comment, startCDATA, and endCDATA events.
711
Tim Petersee826f82001-01-31 19:39:44 +0000712Windows changes
713
714- Build procedure: the zlib project is built in a different way that
715 ensures the zlib header files used can no longer get out of synch with
Tim Peters9ea17ac2001-02-02 05:57:15 +0000716 the zlib binary used. See PCbuild\readme.txt for details. Your old
717 zlib-related directories can be deleted; you'll need to download fresh
718 source for zlib and unpack it into a new directory.
Tim Petersee826f82001-01-31 19:39:44 +0000719
Tim Peters9ea17ac2001-02-02 05:57:15 +0000720- Build: New subproject _test for the benefit of test_capi.py (see above).
721
Tim Petersb16c56f2001-02-02 21:24:51 +0000722- Build: New subproject _symtable, for new DLL _symtable.pyd (a nascent
723 interface to some Python compiler internals).
724
725- Build: Subproject ucnhash is gone, since the code was folded into the
Tim Peters9ea17ac2001-02-02 05:57:15 +0000726 unicodedata subproject.
Tim Petersd7b5e882001-01-25 03:36:26 +0000727
Tim Petersa3a3a032000-11-30 05:22:44 +0000728What's New in Python 2.1 alpha 1?
729=================================
730
731Core language, builtins, and interpreter
732
Marc-André Lemburgebb195b2001-01-20 10:34:52 +0000733- There is a new Unicode companion to the PyObject_Str() API
734 called PyObject_Unicode(). It behaves in the same way as the
735 former, but assures that the returned value is an Unicode object
736 (applying the usual coercion if necessary).
Marc-André Lemburgad7c98e2001-01-17 17:09:53 +0000737
Guido van Rossumf98eda02001-01-17 15:54:45 +0000738- The comparison operators support "rich comparison overloading" (PEP
739 207). C extension types can provide a rich comparison function in
740 the new tp_richcompare slot in the type object. The cmp() function
741 and the C function PyObject_Compare() first try the new rich
742 comparison operators before trying the old 3-way comparison. There
743 is also a new C API PyObject_RichCompare() (which also falls back on
744 the old 3-way comparison, but does not constrain the outcome of the
745 rich comparison to a Boolean result).
746
747 The rich comparison function takes two objects (at least one of
748 which is guaranteed to have the type that provided the function) and
749 an integer indicating the opcode, which can be Py_LT, Py_LE, Py_EQ,
750 Py_NE, Py_GT, Py_GE (for <, <=, ==, !=, >, >=), and returns a Python
751 object, which may be NotImplemented (in which case the tp_compare
752 slot function is used as a fallback, if defined).
753
754 Classes can overload individual comparison operators by defining one
755 or more of the methods__lt__, __le__, __eq__, __ne__, __gt__,
Guido van Rossuma88479f2001-01-18 14:28:08 +0000756 __ge__. There are no explicit "reflected argument" versions of
757 these; instead, __lt__ and __gt__ are each other's reflection,
758 likewise for__le__ and __ge__; __eq__ and __ne__ are their own
759 reflection (similar at the C level). No other implications are
760 made; in particular, Python does not assume that == is the Boolean
761 inverse of !=, or that < is the Boolean inverse of >=. This makes
762 it possible to define types with partial orderings.
Guido van Rossumf98eda02001-01-17 15:54:45 +0000763
764 Classes or types that want to implement (in)equality tests but not
765 the ordering operators (i.e. unordered types) should implement ==
766 and !=, and raise an error for the ordering operators.
767
Guido van Rossuma88479f2001-01-18 14:28:08 +0000768 It is possible to define types whose rich comparison results are not
Guido van Rossumf98eda02001-01-17 15:54:45 +0000769 Boolean; e.g. a matrix type might want to return a matrix of bits
770 for A < B, giving elementwise comparisons. Such types should ensure
771 that any interpretation of their value in a Boolean context raises
772 an exception, e.g. by defining __nonzero__ (or the tp_nonzero slot
773 at the C level) to always raise an exception.
774
Guido van Rossuma88479f2001-01-18 14:28:08 +0000775- Complex numbers use rich comparisons to define == and != but raise
776 an exception for <, <=, > and >=. Unfortunately, this also means
777 that cmp() of two complex numbers raises an exception when the two
778 numbers differ. Since it is not mathematically meaningful to compare
779 complex numbers except for equality, I hope that this doesn't break
780 too much code.
781
Tim Peters3389f192001-02-18 08:48:49 +0000782- The outcome of comparing non-numeric objects of different types is
Tim Peters14495852001-02-18 08:28:33 +0000783 not defined by the language, other than that it's arbitrary but
784 consistent (see the Reference Manual). An implementation detail changed
785 in 2.1a1 such that None now compares less than any other object. Code
786 relying on this new behavior (like code that relied on the previous
787 behavior) does so at its own risk.
788
Barry Warsaw573b5412001-01-15 20:43:18 +0000789- Functions and methods now support getting and setting arbitrarily
790 named attributes (PEP 232). Functions have a new __dict__
791 (a.k.a. func_dict) which hold the function attributes. Methods get
792 and set attributes on their underlying im_func. It is a TypeError
793 to set an attribute on a bound method.
794
Guido van Rossum051e3352001-01-15 19:11:10 +0000795- The xrange() object implementation has been improved so that
796 xrange(sys.maxint) can be used on 64-bit platforms. There's still a
797 limitation that in this case len(xrange(sys.maxint)) can't be
798 calculated, but the common idiom "for i in xrange(sys.maxint)" will
799 work fine as long as the index i doesn't actually reach 2**31.
800 (Python uses regular ints for sequence and string indices; fixing
801 that is much more work.)
802
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000803- Two changes to from...import:
804
Guido van Rossumba381232001-02-03 15:06:40 +0000805 1) "from M import X" now works even if (after loading module M)
806 sys.modules['M'] is not a real module; it's basically a getattr()
807 operation with AttributeError exceptions changed into ImportError.
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000808
809 2) "from M import *" now looks for M.__all__ to decide which names to
810 import; if M.__all__ doesn't exist, it uses M.__dict__.keys() but
811 filters out names starting with '_' as before. Whether or not
812 __all__ exists, there's no restriction on the type of M.
813
Guido van Rossumf61f1662001-01-10 20:13:55 +0000814- File objects have a new method, xreadlines(). This is the fastest
815 way to iterate over all lines in a file:
816
817 for line in file.xreadlines():
818 ...do something to line...
819
820 See the xreadlines module (mentioned below) for how to do this for
821 other file-like objects.
822
823- Even if you don't use file.xreadlines(), you may expect a speedup on
824 line-by-line input. The file.readline() method has been optimized
Tim Petersf29b64d2001-01-15 06:33:19 +0000825 quite a bit in platform-specific ways: on systems (like Linux) that
826 support flockfile(), getc_unlocked(), and funlockfile(), those are
827 used by default. On systems (like Windows) without getc_unlocked(),
828 a complicated (but still thread-safe) method using fgets() is used by
829 default.
830
Tim Petersd52269b2001-01-25 06:23:18 +0000831 You can force use of the fgets() method by #define'ing
832 USE_FGETS_IN_GETLINE at build time (it may be faster than
Tim Petersf29b64d2001-01-15 06:33:19 +0000833 getc_unlocked()).
834
Tim Petersd52269b2001-01-25 06:23:18 +0000835 You can force fgets() not to be used by #define'ing
836 DONT_USE_FGETS_IN_GETLINE (this is the first thing to try if std test
Tim Petersf29b64d2001-01-15 06:33:19 +0000837 test_bufio.py fails -- and let us know if it does!).
838
839- In addition, the fileinput module, while still slower than the other
840 methods on most platforms, has been sped up too, by using
841 file.readlines(sizehint).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000842
843- Support for run-time warnings has been added, including a new
844 command line option (-W) to specify the disposition of warnings.
845 See the description of the warnings module below.
846
847- Extensive changes have been made to the coercion code. This mostly
848 affects extension modules (which can now implement mixed-type
849 numerical operators without having to use coercion), but
850 occasionally, in boundary cases the coercion semantics have changed
851 subtly. Since this was a terrible gray area of the language, this
Guido van Rossumae72d872001-01-11 15:00:14 +0000852 is considered an improvement. Also note that __rcmp__ is no longer
Guido van Rossumf61f1662001-01-10 20:13:55 +0000853 supported -- instead of calling __rcmp__, __cmp__ is called with
Guido van Rossuma88479f2001-01-18 14:28:08 +0000854 reflected arguments.
Guido van Rossumf61f1662001-01-10 20:13:55 +0000855
Guido van Rossumf98eda02001-01-17 15:54:45 +0000856- In connection with the coercion changes, a new built-in singleton
857 object, NotImplemented is defined. This can be returned for
858 operations that wish to indicate they are not implemented for a
859 particular combination of arguments. From C, this is
860 Py_NotImplemented.
861
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000862- The interpreter accepts now bytecode files on the command line even
863 if they do not have a .pyc or .pyo extension. On Linux, after executing
864
Martin v. Löwise214baa2001-02-04 22:37:56 +0000865import imp,sys,string
866magic = string.join(["\\x%.2x" % ord(c) for c in imp.get_magic()],"")
867reg = ':pyc:M::%s::%s:' % (magic, sys.executable)
868open("/proc/sys/fs/binfmt_misc/register","wb").write(reg)
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000869
870 any byte code file can be used as an executable (i.e. as an argument
871 to execve(2)).
872
Tim Peters9940b802000-12-01 07:59:35 +0000873- %[xXo] formats of negative Python longs now produce a sign
Tim Petersa3a3a032000-11-30 05:22:44 +0000874 character. In 1.6 and earlier, they never produced a sign,
875 and raised an error if the value of the long was too large
876 to fit in a Python int. In 2.0, they produced a sign if and
877 only if too large to fit in an int. This was inconsistent
878 across platforms (because the size of an int varies across
879 platforms), and inconsistent with hex() and oct(). Example:
880
881 >>> "%x" % -0x42L
Tim Peters9940b802000-12-01 07:59:35 +0000882 '-42' # in 2.1
Tim Petersa3a3a032000-11-30 05:22:44 +0000883 'ffffffbe' # in 2.0 and before, on 32-bit machines
884 >>> hex(-0x42L)
885 '-0x42L' # in all versions of Python
886
Tim Peters9940b802000-12-01 07:59:35 +0000887 The behavior of %d formats for negative Python longs remains
888 the same as in 2.0 (although in 1.6 and before, they raised
889 an error if the long didn't fit in a Python int).
890
891 %u formats don't make sense for Python longs, but are allowed
892 and treated the same as %d in 2.1. In 2.0, a negative long
893 formatted via %u produced a sign if and only if too large to
894 fit in an int. In 1.6 and earlier, a negative long formatted
895 via %u raised an error if it was too big to fit in an int.
896
Guido van Rossum3661d392000-12-12 22:10:31 +0000897- Dictionary objects have an odd new method, popitem(). This removes
898 an arbitrary item from the dictionary and returns it (in the form of
899 a (key, value) pair). This can be useful for algorithms that use a
900 dictionary as a bag of "to do" items and repeatedly need to pick one
901 item. Such algorithms normally end up running in quadratic time;
902 using popitem() they can usually be made to run in linear time.
903
Tim Peters36cdad12000-12-29 02:06:45 +0000904Standard library
905
Thomas Woutersfe385252001-01-19 23:16:56 +0000906- In the time module, the time argument to the functions strftime,
907 localtime, gmtime, asctime and ctime is now optional, defaulting to
908 the current time (in the local timezone).
909
Guido van Rossumda91f222001-01-15 16:36:08 +0000910- The ftplib module now defaults to passive mode, which is deemed a
911 more useful default given that clients are often inside firewalls
912 these days. Note that this could break if ftplib is used to connect
913 to a *server* that is inside a firewall, from outside; this is
914 expected to be a very rare situation. To fix that, you can call
915 ftp.set_pasv(0).
916
Martin v. Löwis10a27872001-01-13 09:54:41 +0000917- The module site now treats .pth files not only for path configuration,
918 but also supports extensions to the initialization code: Lines starting
919 with import are executed.
920
Guido van Rossumf61f1662001-01-10 20:13:55 +0000921- There's a new module, warnings, which implements a mechanism for
922 issuing and filtering warnings. There are some new built-in
923 exceptions that serve as warning categories, and a new command line
924 option, -W, to control warnings (e.g. -Wi ignores all warnings, -We
925 turns warnings into errors). warnings.warn(message[, category])
926 issues a warning message; this can also be called from C as
927 PyErr_Warn(category, message).
928
929- A new module xreadlines was added. This exports a single factory
930 function, xreadlines(). The intention is that this code is the
931 absolutely fastest way to iterate over all lines in an open
932 file(-like) object:
933
934 import xreadlines
935 for line in xreadlines.xreadlines(file):
936 ...do something to line...
937
938 This is equivalent to the previous the speed record holder using
939 file.readlines(sizehint). Note that if file is a real file object
940 (as opposed to a file-like object), this is equivalent:
941
942 for line in file.xreadlines():
943 ...do something to line...
944
Tim Peters36cdad12000-12-29 02:06:45 +0000945- The bisect module has new functions bisect_left, insort_left,
946 bisect_right and insort_right. The old names bisect and insort
947 are now aliases for bisect_right and insort_right. XXX_right
948 and XXX_left methods differ in what happens when the new element
949 compares equal to one or more elements already in the list: the
950 XXX_left methods insert to the left, the XXX_right methods to the
Tim Peters742bb6f2001-01-05 08:05:32 +0000951 right. Code that doesn't care where equal elements end up should
952 continue to use the old, short names ("bisect" and "insort").
Tim Peters36cdad12000-12-29 02:06:45 +0000953
Andrew M. Kuchlingf6f3a892001-01-13 14:53:34 +0000954- The new curses.panel module wraps the panel library that forms part
955 of SYSV curses and ncurses. Contributed by Thomas Gellekum.
956
Guido van Rossumf61f1662001-01-10 20:13:55 +0000957- The SocketServer module now sets the allow_reuse_address flag by
958 default in the TCPServer class.
959
960- A new function, sys._getframe(), returns the stack frame pointer of
961 the caller. This is intended only as a building block for
962 higher-level mechanisms such as string interpolation.
963
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000964- The pyexpat module supports a number of new handlers, which are
965 available only in expat 1.2. If invocation of a callback fails, it
966 will report an additional frame in the traceback. Parser objects
967 participate now in garbage collection. If expat reports an unknown
968 encoding, pyexpat will try to use a Python codec; that works only
969 for single-byte charsets. The parser type objects is exposed as
970 XMLParserObject.
971
972- xml.dom now offers standard definitions for symbolic node type and
973 exception code constants, and a hierarchy of DOM exceptions. minidom
974 was adjusted to use them.
975
976- The conformance of xml.dom.minidom to the DOM specification was
977 improved. It detects a number of additional error cases; the
978 previous/next relationship works even when the tree is modified;
979 Node supports the normalize() method; NamedNodeMap, DocumentType and
980 DOMImplementation classes were added; Element supports the
981 hasAttribute and hasAttributeNS methods; and Text supports the splitText
982 method.
983
Guido van Rossumf61f1662001-01-10 20:13:55 +0000984Build issues
985
Guido van Rossum1e33bdc2001-01-23 03:17:00 +0000986- For Unix (and Unix-compatible) builds, configuration and building of
987 extension modules is now greatly automated. Rather than having to
988 edit the Modules/Setup file to indicate which modules should be
989 built and where their include files and libraries are, a
990 distutils-based setup.py script now takes care of building most
991 extension modules. All extension modules built this way are built
992 as shared libraries. Only a few modules that must be linked
993 statically are still listed in the Setup file; you won't need to
994 edit their configuration.
995
996- Python should now build out of the box on Cygwin. If it doesn't,
997 mail to Jason Tishler (jlt63 at users.sourceforge.net).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000998
999- Python now always uses its own (renamed) implementation of getopt()
1000 -- there's too much variation among C library getopt()
1001 implementations.
1002
1003- C++ compilers are better supported; the CXX macro is always set to a
1004 C++ compiler if one is found.
Tim Peters36cdad12000-12-29 02:06:45 +00001005
Tim Petersd92dfe02000-12-12 01:18:41 +00001006Windows changes
1007
1008- select module: By default under Windows, a select() call
1009 can specify no more than 64 sockets. Python now boosts
1010 this Microsoft default to 512. If you need even more than
1011 that, see the MS docs (you'll need to #define FD_SETSIZE
1012 and recompile Python from source).
1013
Guido van Rossumf61f1662001-01-10 20:13:55 +00001014- Support for Windows 3.1, DOS and OS/2 is gone. The Lib/dos-8x3
1015 subdirectory is no more!
1016
Tim Petersa3a3a032000-11-30 05:22:44 +00001017
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001018What's New in Python 2.0?
Fred Drake1a640502000-10-16 20:27:25 +00001019=========================
Guido van Rossum61000331997-08-15 04:39:58 +00001020
Guido van Rossum8ed602b2000-09-01 22:34:33 +00001021Below is a list of all relevant changes since release 1.6. Older
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001022changes are in the file HISTORY. If you are making the jump directly
1023from Python 1.5.2 to 2.0, make sure to read the section for 1.6 in the
1024HISTORY file! Many important changes listed there.
Guido van Rossum61000331997-08-15 04:39:58 +00001025
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001026Alternatively, a good overview of the changes between 1.5.2 and 2.0 is
1027the document "What's New in Python 2.0" by Kuchling and Moshe Zadka:
1028http://starship.python.net/crew/amk/python/writing/new-python/.
Guido van Rossum1f83cce1997-10-06 21:04:35 +00001029
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001030--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)
Guido van Rossum437cfe81999-04-08 20:17:57 +00001031
1032======================================================================
1033
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001034What's new in 2.0 (since release candidate 1)?
1035==============================================
1036
1037Standard library
1038
1039- The copy_reg module was modified to clarify its intended use: to
1040 register pickle support for extension types, not for classes.
1041 pickle() will raise a TypeError if it is passed a class.
1042
1043- Fixed a bug in gettext's "normalize and expand" code that prevented
1044 it from finding an existing .mo file.
1045
1046- Restored support for HTTP/0.9 servers in httplib.
1047
Tim Peters989b7b92000-10-16 20:24:53 +00001048- The math module was changed to stop raising OverflowError in case of
1049 underflow, and return 0 instead in underflow cases. Whether Python
1050 used to raise OverflowError in case of underflow was platform-
1051 dependent (it did when the platform math library set errno to ERANGE
1052 on underflow).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001053
1054- Fixed a bug in StringIO that occurred when the file position was not
1055 at the end of the file and write() was called with enough data to
1056 extend past the end of the file.
1057
1058- Fixed a bug that caused Tkinter error messages to get lost on
1059 Windows. The bug was fixed by replacing direct use of
1060 interp->result with Tcl_GetStringResult(interp).
1061
1062- Fixed bug in urllib2 that caused it to fail when it received an HTTP
1063 redirect response.
1064
1065- Several changes were made to distutils: Some debugging code was
1066 removed from util. Fixed the installer used when an external zip
1067 program (like WinZip) is not found; the source code for this
1068 installer is in Misc/distutils. check_lib() was modified to behave
1069 more like AC_CHECK_LIB by add other_libraries() as a parameter. The
1070 test for whether installed modules are on sys.path was changed to
1071 use both normcase() and normpath().
1072
Jeremy Hyltond867a2c2000-10-16 20:41:38 +00001073- Several minor bugs were fixed in the xml package (the minidom,
1074 pulldom, expatreader, and saxutils modules).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001075
1076- The regression test driver (regrtest.py) behavior when invoked with
1077 -l changed: It now reports a count of objects that are recognized as
1078 garbage but not freed by the garbage collector.
1079
Tim Peters989b7b92000-10-16 20:24:53 +00001080- The regression test for the math module was changed to test
1081 exceptional behavior when the test is run in verbose mode. Python
1082 cannot yet guarantee consistent exception behavior across platforms,
1083 so the exception part of test_math is run only in verbose mode, and
1084 may fail on your platform.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001085
1086Internals
1087
1088- PyOS_CheckStack() has been disabled on Win64, where it caused
1089 test_sre to fail.
1090
1091Build issues
1092
1093- Changed compiler flags, so that gcc is always invoked with -Wall and
1094 -Wstrict-prototypes. Users compiling Python with GCC should see
1095 exactly one warning, except if they have passed configure the
Tim Peters989b7b92000-10-16 20:24:53 +00001096 --with-pydebug flag. The expected warning is for getopt() in
Tim Petersadfb94f2000-10-16 20:51:33 +00001097 Modules/main.c. This warning will be fixed for Python 2.1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001098
Tim Petersa3a3a032000-11-30 05:22:44 +00001099- Fixed configure to add -threads argument during linking on OSF1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001100
1101Tools and other miscellany
1102
1103- The compiler in Tools/compiler was updated to support the new
1104 language features introduced in 2.0: extended print statement, list
1105 comprehensions, and augmented assignments. The new compiler should
1106 also be backwards compatible with Python 1.5.2; the compiler will
1107 always generate code for the version of the interpreter it runs
Tim Petersa3a3a032000-11-30 05:22:44 +00001108 under.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001109
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001110What's new in 2.0 release candidate 1 (since beta 2)?
1111=====================================================
1112
Jeremy Hylton6040aaa2000-10-09 21:27:22 +00001113What is release candidate 1?
1114
1115We believe that release candidate 1 will fix all known bugs that we
1116intend to fix for the 2.0 final release. This release should be a bit
1117more stable than the previous betas. We would like to see even more
1118widespread testing before the final release, so we are producing this
1119release candidate. The final release will be exactly the same unless
1120any show-stopping (or brown bag) bugs are found by testers of the
1121release candidate.
1122
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001123All the changes since the last beta release are bug fixes or changes
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001124to support building Python for specific platforms.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001125
1126Core language, builtins, and interpreter
1127
1128- A bug that caused crashes when __coerce__ was used with augmented
1129 assignment, e.g. +=, was fixed.
1130
1131- Raise ZeroDivisionError when raising zero to a negative number,
1132 e.g. 0.0 ** -2.0. Note that math.pow is unrelated to the builtin
1133 power operator and the result of math.pow(0.0, -2.0) will vary by
1134 platform. On Linux, it raises a ValueError.
1135
1136- A bug in Unicode string interpolation was fixed that occasionally
1137 caused errors with formats including "%%". For example, the
1138 following expression "%% %s" % u"abc" no longer raises a TypeError.
1139
1140- Compilation of deeply nested expressions raises MemoryError instead
1141 of SyntaxError, e.g. eval("[" * 50 + "]" * 50).
1142
1143- In 2.0b2 on Windows, the interpreter wrote .pyc files in text mode,
1144 rendering them useless. They are now written in binary mode again.
1145
1146Standard library
1147
1148- Keyword arguments are now accepted for most pattern and match object
1149 methods in SRE, the standard regular expression engine.
1150
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001151- In SRE, fixed error with negative lookahead and lookbehind that
Jeremy Hylton32e20ff2000-10-09 19:48:11 +00001152 manifested itself as a runtime error in patterns like "(?<!abc)(def)".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001153
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001154- Several bugs in the Unicode handling and error handling in _tkinter
1155 were fixed.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001156
1157- Fix memory management errors in Merge() and Tkapp_Call() routines.
1158
1159- Several changes were made to cStringIO to make it compatible with
1160 the file-like object interface and with StringIO. If operations are
1161 performed on a closed object, an exception is raised. The truncate
1162 method now accepts a position argument and readline accepts a size
Tim Petersa3a3a032000-11-30 05:22:44 +00001163 argument.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001164
1165- There were many changes made to the linuxaudiodev module and its
1166 test suite; as a result, a short, unexpected audio sample should now
Tim Petersa3a3a032000-11-30 05:22:44 +00001167 play when the regression test is run.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001168
1169 Note that this module is named poorly, because it should work
1170 correctly on any platform that supports the Open Sound System
Tim Petersa3a3a032000-11-30 05:22:44 +00001171 (OSS).
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001172
1173 The module now raises exceptions when errors occur instead of
1174 crashing. It also defines the AFMT_A_LAW format (logarithmic A-law
1175 audio) and defines a getptr() method that calls the
1176 SNDCTL_DSP_GETxPTR ioctl defined in the OSS Programmer's Guide.
1177
1178- The library_version attribute, introduced in an earlier beta, was
1179 removed because it can not be supported with early versions of the C
1180 readline library, which provides no way to determine the version at
1181 compile-time.
1182
1183- The binascii module is now enabled on Win64.
1184
Tim Peters46446d62000-10-09 21:19:31 +00001185- tokenize.py no longer suffers "recursion depth" errors when parsing
1186 programs with very long string literals.
1187
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001188Internals
1189
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001190- Fixed several buffer overflow vulnerabilities in calculate_path(),
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001191 which is called when the interpreter starts up to determine where
1192 the standard library is installed. These vulnerabilities affect all
1193 previous versions of Python and can be exploited by setting very
1194 long values for PYTHONHOME or argv[0]. The risk is greatest for a
1195 setuid Python script, although use of the wrapper in
1196 Misc/setuid-prog.c will eliminate the vulnerability.
1197
1198- Fixed garbage collection bugs in instance creation that were
1199 triggered when errors occurred during initialization. The solution,
1200 applied in cPickle and in PyInstance_New(), is to call
1201 PyObject_GC_Init() after the initialization of the object's
1202 container attributes is complete.
1203
1204- pyexpat adds definitions of PyModule_AddStringConstant and
1205 PyModule_AddObject if the Python version is less than 2.0, which
1206 provides compatibility with PyXML on Python 1.5.2.
1207
1208- If the platform has a bogus definition for LONG_BIT (the number of
1209 bits in a long), an error will be reported at compile time.
1210
1211- Fix bugs in _PyTuple_Resize() which caused hard-to-interpret garbage
1212 collection crashes and possibly other, unreported crashes.
1213
1214- Fixed a memory leak in _PyUnicode_Fini().
1215
1216Build issues
1217
1218- configure now accepts a --with-suffix option that specifies the
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001219 executable suffix. This is useful for builds on Cygwin and Mac OS
Tim Petersa3a3a032000-11-30 05:22:44 +00001220 X, for example.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001221
1222- The mmap.PAGESIZE constant is now initialized using sysconf when
1223 possible, which eliminates a dependency on -lucb for Reliant UNIX.
1224
1225- The md5 file should now compile on all platforms.
1226
1227- The select module now compiles on platforms that do not define
1228 POLLRDNORM and related constants.
1229
1230- Darwin (Mac OS X): Initial support for static builds on this
Tim Petersa3a3a032000-11-30 05:22:44 +00001231 platform.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001232
Jeremy Hylton10921202000-10-09 18:34:12 +00001233- BeOS: A number of changes were made to the build and installation
1234 process. ar-fake now operates on a directory of object files.
1235 dl_export.h is gone, and its macros now appear on the mwcc command
1236 line during build on PPC BeOS.
1237
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001238- Platform directory in lib/python2.0 is "plat-beos5" (or
Jeremy Hylton10921202000-10-09 18:34:12 +00001239 "plat-beos4", if building on BeOS 4.5), rather than "plat-beos".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001240
1241- Cygwin: Support for shared libraries, Tkinter, and sockets.
1242
1243- SunOS 4.1.4_JL: Fix test for directory existence in configure.
1244
1245Tools and other miscellany
1246
1247- Removed debugging prints from main used with freeze.
1248
Tim Peters46446d62000-10-09 21:19:31 +00001249- IDLE auto-indent no longer crashes when it encounters Unicode
1250 characters.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001251
1252What's new in 2.0 beta 2 (since beta 1)?
1253========================================
1254
1255Core language, builtins, and interpreter
1256
Tim Peters482c0212000-09-26 06:33:09 +00001257- Add support for unbounded ints in %d,i,u,x,X,o formats; for example
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001258 "%d" % 2L**64 == "18446744073709551616".
Jeremy Hylton1b618592000-09-26 05:32:36 +00001259
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001260- Add -h and -V command line options to print the usage message and
1261 Python version number and exit immediately.
1262
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001263- eval() and exec accept Unicode objects as code parameters.
1264
1265- getattr() and setattr() now also accept Unicode objects for the
1266 attribute name, which are converted to strings using the default
1267 encoding before lookup.
1268
1269- Multiplication on string and Unicode now does proper bounds
1270 checking; e.g. 'a' * 65536 * 65536 will raise ValueError, "repeated
1271 string is too long."
1272
1273- Better error message when continue is found in try statement in a
Tim Petersa3a3a032000-11-30 05:22:44 +00001274 loop.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001275
Jeremy Hylton1b618592000-09-26 05:32:36 +00001276
1277Standard library and extensions
1278
Guido van Rossum5b08f132001-04-16 02:05:23 +00001279- socket module: the OpenSSL code now adds support for RAND_status()
1280 and EGD (Entropy Gathering Device).
1281
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001282- array: reverse() method of array now works. buffer_info() now does
Jeremy Hylton1b618592000-09-26 05:32:36 +00001283 argument checking; it still takes no arguments.
1284
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001285- asyncore/asynchat: Included most recent version from Sam Rushing.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001286
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001287- cgi: Accept '&' or ';' as separator characters when parsing form data.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001288
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001289- CGIHTTPServer: Now works on Windows (and perhaps even Mac).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001290
1291- ConfigParser: When reading the file, options spelled in upper case
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001292 letters are now correctly converted to lowercase.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001293
1294- copy: Copy Unicode objects atomically.
1295
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001296- cPickle: Fail gracefully when copy_reg can't be imported.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001297
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001298- cStringIO: Implemented readlines() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001299
Fred Drake67233bc2000-09-26 16:40:27 +00001300- dbm: Add get() and setdefault() methods to dbm object. Add constant
1301 `library' to module that names the library used. Added doc strings
1302 and method names to error messages. Uses configure to determine
1303 which ndbm.h file to include; Berkeley DB's nbdm and GDBM's ndbm is
1304 now available options.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001305
1306- distutils: Update to version 0.9.3.
1307
1308- dl: Add several dl.RTLD_ constants.
1309
1310- fpectl: Now supported on FreeBSD.
1311
1312- gc: Add DEBUG_SAVEALL option. When enabled all garbage objects
1313 found by the collector will be saved in gc.garbage. This is useful
1314 for debugging a program that creates reference cycles.
1315
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001316- httplib: Three changes: Restore support for set_debuglevel feature
Jeremy Hylton1b618592000-09-26 05:32:36 +00001317 of HTTP class. Do not close socket on zero-length response. Do not
1318 crash when server sends invalid content-length header.
1319
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001320- mailbox: Mailbox class conforms better to qmail specifications.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001321
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001322- marshal: When reading a short, sign-extend on platforms where shorts
1323 are bigger than 16 bits. When reading a long, repair the unportable
1324 sign extension that was being done for 64-bit machines. (It assumed
1325 that signed right shift sign-extends.)
1326
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001327- operator: Add contains(), invert(), __invert__() as aliases for
1328 __contains__(), inv(), and __inv__() respectively.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001329
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001330- os: Add support for popen2() and popen3() on all platforms where
1331 fork() exists. (popen4() is still in the works.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00001332
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001333- os: (Windows only:) Add startfile() function that acts like double-
Tim Peters482c0212000-09-26 06:33:09 +00001334 clicking on a file in Explorer (or passing the file name to the
1335 DOS "start" command).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001336
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001337- os.path: (Windows, DOS:) Treat trailing colon correctly in
Tim Peters482c0212000-09-26 06:33:09 +00001338 os.path.join. os.path.join("a:", "b") yields "a:b".
Jeremy Hylton1b618592000-09-26 05:32:36 +00001339
1340- pickle: Now raises ValueError when an invalid pickle that contains
1341 a non-string repr where a string repr was expected. This behavior
1342 matches cPickle.
1343
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001344- posixfile: Remove broken __del__() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001345
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001346- py_compile: support CR+LF line terminators in source file.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001347
1348- readline: Does not immediately exit when ^C is hit when readline and
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001349 threads are configured. Adds definition of rl_library_version. (The
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001350 latter addition requires GNU readline 2.2 or later.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00001351
1352- rfc822: Domain literals returned by AddrlistClass method
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001353 getdomainliteral() are now properly wrapped in brackets.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001354
1355- site: sys.setdefaultencoding() should only be called in case the
Tim Peters482c0212000-09-26 06:33:09 +00001356 standard default encoding ("ascii") is changed. This saves quite a
Jeremy Hylton1b618592000-09-26 05:32:36 +00001357 few cycles during startup since the first call to
1358 setdefaultencoding() will initialize the codec registry and the
1359 encodings package.
1360
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001361- socket: Support for size hint in readlines() method of object returned
1362 by makefile().
Jeremy Hylton1b618592000-09-26 05:32:36 +00001363
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001364- sre: Added experimental expand() method to match objects. Does not
Jeremy Hylton625915e2000-10-02 13:43:33 +00001365 use buffer interface on Unicode strings. Does not hang if group id
Jeremy Hylton1b618592000-09-26 05:32:36 +00001366 is followed by whitespace.
1367
Tim Petersa3a3a032000-11-30 05:22:44 +00001368- StringIO: Size hint in readlines() is now supported as documented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001369
1370- struct: Check ranges for bytes and shorts.
1371
1372- urllib: Improved handling of win32 proxy settings. Fixed quote and
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001373 quote_plus functions so that the always encode a comma.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001374
1375- Tkinter: Image objects are now guaranteed to have unique ids. Set
1376 event.delta to zero if Tk version doesn't support mousewheel.
1377 Removed some debugging prints.
1378
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001379- UserList: now implements __contains__().
Jeremy Hylton1b618592000-09-26 05:32:36 +00001380
Fred Drake67233bc2000-09-26 16:40:27 +00001381- webbrowser: On Windows, use os.startfile() instead of os.popen(),
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001382 which works around a bug in Norton AntiVirus 2000 that leads directly
1383 to a Blue Screen freeze.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001384
1385- xml: New version detection code allows PyXML to override standard
1386 XML package if PyXML version is greater than 0.6.1.
1387
Fred Drake64bb3802000-09-26 16:21:35 +00001388- xml.dom: DOM level 1 support for basic XML. Includes xml.dom.minidom
1389 (conventional DOM), and xml.dom.pulldom, which allows building the DOM
1390 tree only for nodes which are sufficiently interesting to a specific
1391 application. Does not provide the HTML-specific extensions. Still
1392 undocumented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001393
Fred Drake64bb3802000-09-26 16:21:35 +00001394- xml.sax: SAX 2 support for Python, including all the handler
1395 interfaces needed to process XML 1.0 compliant XML. Some
1396 documentation is already available.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001397
Fred Drake64bb3802000-09-26 16:21:35 +00001398- pyexpat: Renamed to xml.parsers.expat since this is part of the new,
1399 packagized XML support.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001400
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001401
Jeremy Hylton1b618592000-09-26 05:32:36 +00001402C API
1403
1404- Add three new convenience functions for module initialization --
1405 PyModule_AddObject(), PyModule_AddIntConstant(), and
1406 PyModule_AddStringConstant().
1407
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001408- Cleaned up definition of NULL in C source code; all definitions were
Jeremy Hylton1b618592000-09-26 05:32:36 +00001409 removed and add #error to Python.h if NULL isn't defined after
1410 #include of stdio.h.
1411
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001412- Py_PROTO() macros that were removed in 2.0b1 have been restored for
Jeremy Hylton1b618592000-09-26 05:32:36 +00001413 backwards compatibility (at the source level) with old extensions.
1414
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001415- A wrapper API was added for signal() and sigaction(). Instead of
1416 either function, always use PyOS_getsig() to get a signal handler
1417 and PyOS_setsig() to set one. A new convenience typedef
1418 PyOS_sighandler_t is defined for the type of signal handlers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001419
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001420- Add PyString_AsStringAndSize() function that provides access to the
Jeremy Hylton1b618592000-09-26 05:32:36 +00001421 internal data buffer and size of a string object -- or the default
1422 encoded version of a Unicode object.
1423
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001424- PyString_Size() and PyString_AsString() accept Unicode objects.
1425
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001426- The standard header <limits.h> is now included by Python.h (if it
Fred Drake64bb3802000-09-26 16:21:35 +00001427 exists). INT_MAX and LONG_MAX will always be defined, even if
1428 <limits.h> is not available.
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001429
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001430- PyFloat_FromString takes a second argument, pend, that was
1431 effectively useless. It is now officially useless but preserved for
1432 backwards compatibility. If the pend argument is not NULL, *pend is
1433 set to NULL.
1434
1435- PyObject_GetAttr() and PyObject_SetAttr() now accept Unicode objects
1436 for the attribute name. See note on getattr() above.
1437
1438- A few bug fixes to argument processing for Unicode.
1439 PyArg_ParseTupleAndKeywords() now accepts "es#" and "es".
1440 PyArg_Parse() special cases "s#" for Unicode objects; it returns a
1441 pointer to the default encoded string data instead of to the raw
Tim Petersa3a3a032000-11-30 05:22:44 +00001442 UTF-16.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001443
1444- Py_BuildValue accepts B format (for bgen-generated code).
1445
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001446
Jeremy Hylton1b618592000-09-26 05:32:36 +00001447Internals
1448
1449- On Unix, fix code for finding Python installation directory so that
1450 it works when argv[0] is a relative path.
1451
Andrew M. Kuchlinga1099be2000-12-15 01:16:43 +00001452- Added a true unicode_internal_encode() function and fixed the
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001453 unicode_internal_decode function() to support Unicode objects directly
Jeremy Hylton1b618592000-09-26 05:32:36 +00001454 rather than by generating a copy of the object.
1455
Tim Peters482c0212000-09-26 06:33:09 +00001456- Several of the internal Unicode tables are much smaller now, and
1457 the source code should be much friendlier to weaker compilers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001458
Jeremy Hylton97693b02000-09-26 17:42:51 +00001459- In the garbage collector: Fixed bug in collection of tuples. Fixed
1460 bug that caused some instances to be removed from the container set
1461 while they were still live. Fixed parsing in gc.set_debug() for
1462 platforms where sizeof(long) > sizeof(int).
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001463
1464- Fixed refcount problem in instance deallocation that only occurred
1465 when Py_REF_DEBUG was defined and Py_TRACE_REFS was not.
1466
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001467- On Windows, getpythonregpath is now protected against null data in
1468 registry key.
1469
1470- On Unix, create .pyc/.pyo files with O_EXCL flag to avoid a race
Tim Petersa3a3a032000-11-30 05:22:44 +00001471 condition.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001472
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001473
Jeremy Hylton1b618592000-09-26 05:32:36 +00001474Build and platform-specific issues
1475
1476- Better support of GNU Pth via --with-pth configure option.
1477
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001478- Python/C API now properly exposed to dynamically-loaded extension
1479 modules on Reliant UNIX.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001480
1481- Changes for the benefit of SunOS 4.1.4 (really!). mmapmodule.c:
1482 Don't define MS_SYNC to be zero when it is undefined. Added missing
1483 prototypes in posixmodule.c.
1484
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001485- Improved support for HP-UX build. Threads should now be correctly
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001486 configured (on HP-UX 10.20 and 11.00).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001487
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001488- Fix largefile support on older NetBSD systems and OpenBSD by adding
1489 define for TELL64.
1490
1491
1492Tools and other miscellany
1493
1494- ftpmirror: Call to main() is wrapped in if __name__ == "__main__".
1495
1496- freeze: The modulefinder now works with 2.0 opcodes.
1497
Tim Petersa3a3a032000-11-30 05:22:44 +00001498- IDLE:
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001499 Move hackery of sys.argv until after the Tk instance has been
1500 created, which allows the application-specific Tkinter
1501 initialization to be executed if present; also pass an explicit
1502 className parameter to the Tk() constructor.
Fred Drake64bb3802000-09-26 16:21:35 +00001503
Jeremy Hylton1b618592000-09-26 05:32:36 +00001504
1505What's new in 2.0 beta 1?
1506=========================
1507
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001508Source Incompatibilities
1509------------------------
1510
1511None. Note that 1.6 introduced several incompatibilities with 1.5.2,
1512such as single-argument append(), connect() and bind(), and changes to
1513str(long) and repr(float).
1514
1515
1516Binary Incompatibilities
1517------------------------
1518
1519- Third party extensions built for Python 1.5.x or 1.6 cannot be used
1520with Python 2.0; these extensions will have to be rebuilt for Python
15212.0.
1522
1523- On Windows, attempting to import a third party extension built for
1524Python 1.5.x or 1.6 results in an immediate crash; there's not much we
1525can do about this. Check your PYTHONPATH environment variable!
1526
1527- Python bytecode files (*.pyc and *.pyo) are not compatible between
1528releases.
1529
1530
1531Overview of Changes Since 1.6
1532-----------------------------
1533
1534There are many new modules (including brand new XML support through
1535the xml package, and i18n support through the gettext module); a list
1536of all new modules is included below. Lots of bugs have been fixed.
1537
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001538The process for making major new changes to the language has changed
1539since Python 1.6. Enhancements must now be documented by a Python
1540Enhancement Proposal (PEP) before they can be accepted.
1541
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001542There are several important syntax enhancements, described in more
1543detail below:
1544
1545 - Augmented assignment, e.g. x += 1
1546
1547 - List comprehensions, e.g. [x**2 for x in range(10)]
1548
1549 - Extended import statement, e.g. import Module as Name
1550
1551 - Extended print statement, e.g. print >> file, "Hello"
1552
1553Other important changes:
1554
1555 - Optional collection of cyclical garbage
1556
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001557Python Enhancement Proposal (PEP)
1558---------------------------------
1559
1560PEP stands for Python Enhancement Proposal. A PEP is a design
1561document providing information to the Python community, or describing
1562a new feature for Python. The PEP should provide a concise technical
1563specification of the feature and a rationale for the feature.
1564
1565We intend PEPs to be the primary mechanisms for proposing new
1566features, for collecting community input on an issue, and for
1567documenting the design decisions that have gone into Python. The PEP
1568author is responsible for building consensus within the community and
1569documenting dissenting opinions.
1570
1571The PEPs are available at http://python.sourceforge.net/peps/.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001572
1573Augmented Assignment
1574--------------------
1575
1576This must have been the most-requested feature of the past years!
1577Eleven new assignment operators were added:
1578
Guido van Rossume905e952000-09-05 12:42:46 +00001579 += -= *= /= %= **= <<= >>= &= ^= |=
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001580
1581For example,
1582
1583 A += B
1584
1585is similar to
1586
1587 A = A + B
1588
1589except that A is evaluated only once (relevant when A is something
1590like dict[index].attr).
1591
1592However, if A is a mutable object, A may be modified in place. Thus,
1593if A is a number or a string, A += B has the same effect as A = A+B
1594(except A is only evaluated once); but if a is a list, A += B has the
1595same effect as A.extend(B)!
1596
1597Classes and built-in object types can override the new operators in
1598order to implement the in-place behavior; the not-in-place behavior is
1599used automatically as a fallback when an object doesn't implement the
1600in-place behavior. For classes, the method name is derived from the
1601method name for the corresponding not-in-place operator by inserting
1602an 'i' in front of the name, e.g. __iadd__ implements in-place
1603__add__.
1604
1605Augmented assignment was implemented by Thomas Wouters.
1606
1607
1608List Comprehensions
1609-------------------
1610
1611This is a flexible new notation for lists whose elements are computed
1612from another list (or lists). The simplest form is:
1613
1614 [<expression> for <variable> in <sequence>]
1615
Guido van Rossum56db0952000-09-06 23:34:25 +00001616For example, [i**2 for i in range(4)] yields the list [0, 1, 4, 9].
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001617This is more efficient than a for loop with a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001618
1619You can also add a condition:
1620
1621 [<expression> for <variable> in <sequence> if <condition>]
1622
1623For example, [w for w in words if w == w.lower()] would yield the list
1624of words that contain no uppercase characters. This is more efficient
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001625than a for loop with an if statement and a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001626
1627You can also have nested for loops and more than one 'if' clause. For
1628example, here's a function that flattens a sequence of sequences::
1629
1630 def flatten(seq):
1631 return [x for subseq in seq for x in subseq]
1632
1633 flatten([[0], [1,2,3], [4,5], [6,7,8,9], []])
1634
1635This prints
1636
1637 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
1638
1639List comprehensions originated as a patch set from Greg Ewing; Skip
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001640Montanaro and Thomas Wouters also contributed. Described by PEP 202.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001641
1642
1643Extended Import Statement
1644-------------------------
1645
1646Many people have asked for a way to import a module under a different
1647name. This can be accomplished like this:
1648
1649 import foo
1650 bar = foo
1651 del foo
1652
1653but this common idiom gets old quickly. A simple extension of the
1654import statement now allows this to be written as follows:
1655
1656 import foo as bar
1657
1658There's also a variant for 'from ... import':
1659
1660 from foo import bar as spam
1661
1662This also works with packages; e.g. you can write this:
1663
1664 import test.regrtest as regrtest
1665
1666Note that 'as' is not a new keyword -- it is recognized only in this
1667context (this is only possible because the syntax for the import
1668statement doesn't involve expressions).
1669
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001670Implemented by Thomas Wouters. Described by PEP 221.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001671
1672
1673Extended Print Statement
1674------------------------
1675
1676Easily the most controversial new feature, this extension to the print
1677statement adds an option to make the output go to a different file
1678than the default sys.stdout.
1679
1680For example, to write an error message to sys.stderr, you can now
1681write:
1682
1683 print >> sys.stderr, "Error: bad dog!"
1684
1685As a special feature, if the expression used to indicate the file
Fred Drake45888ff2000-09-29 17:09:11 +00001686evaluates to None, the current value of sys.stdout is used. Thus:
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001687
1688 print >> None, "Hello world"
1689
1690is equivalent to
1691
1692 print "Hello world"
1693
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001694Design and implementation by Barry Warsaw. Described by PEP 214.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001695
1696
1697Optional Collection of Cyclical Garbage
1698---------------------------------------
1699
1700Python is now equipped with a garbage collector that can hunt down
1701cyclical references between Python objects. It's no replacement for
1702reference counting; in fact, it depends on the reference counts being
1703correct, and decides that a set of objects belong to a cycle if all
1704their reference counts can be accounted for from their references to
1705each other. This devious scheme was first proposed by Eric Tiedemann,
1706and brought to implementation by Neil Schemenauer.
1707
1708There's a module "gc" that lets you control some parameters of the
1709garbage collection. There's also an option to the configure script
1710that lets you enable or disable the garbage collection. In 2.0b1,
1711it's on by default, so that we (hopefully) can collect decent user
1712experience with this new feature. There are some questions about its
Fred Drake9f11cf82000-09-29 17:54:40 +00001713performance. If it proves to be too much of a problem, we'll turn it
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001714off by default in the final 2.0 release.
1715
1716
1717Smaller Changes
1718---------------
1719
1720A new function zip() was added. zip(seq1, seq2, ...) is equivalent to
1721map(None, seq1, seq2, ...) when the sequences have the same length;
1722i.e. zip([1,2,3], [10,20,30]) returns [(1,10), (2,20), (3,30)]. When
1723the lists are not all the same length, the shortest list wins:
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001724zip([1,2,3], [10,20]) returns [(1,10), (2,20)]. See PEP 201.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001725
1726sys.version_info is a tuple (major, minor, micro, level, serial).
1727
1728Dictionaries have an odd new method, setdefault(key, default).
1729dict.setdefault(key, default) returns dict[key] if it exists; if not,
1730it sets dict[key] to default and returns that value. Thus:
1731
1732 dict.setdefault(key, []).append(item)
1733
1734does the same work as this common idiom:
1735
1736 if not dict.has_key(key):
1737 dict[key] = []
1738 dict[key].append(item)
1739
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001740There are two new variants of SyntaxError that are raised for
1741indentation-related errors: IndentationError and TabError.
1742
1743Changed \x to consume exactly two hex digits; see PEP 223. Added \U
1744escape that consumes exactly eight hex digits.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001745
1746The limits on the size of expressions and file in Python source code
1747have been raised from 2**16 to 2**32. Previous versions of Python
1748were limited because the maximum argument size the Python VM accepted
1749was 2**16. This limited the size of object constructor expressions,
1750e.g. [1,2,3] or {'a':1, 'b':2}, and the size of source files. This
1751limit was raised thanks to a patch by Charles Waldman that effectively
1752fixes the problem. It is now much more likely that you will be
1753limited by available memory than by an arbitrary limit in Python.
1754
1755The interpreter's maximum recursion depth can be modified by Python
1756programs using sys.getrecursionlimit and sys.setrecursionlimit. This
1757limit is the maximum number of recursive calls that can be made by
1758Python code. The limit exists to prevent infinite recursion from
1759overflowing the C stack and causing a core dump. The default value is
17601000. The maximum safe value for a particular platform can be found
1761by running Misc/find_recursionlimit.py.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001762
1763New Modules and Packages
1764------------------------
1765
1766atexit - for registering functions to be called when Python exits.
1767
1768imputil - Greg Stein's alternative API for writing custom import
1769hooks.
1770
1771pyexpat - an interface to the Expat XML parser, contributed by Paul
1772Prescod.
1773
1774xml - a new package with XML support code organized (so far) in three
1775subpackages: xml.dom, xml.sax, and xml.parsers. Describing these
1776would fill a volume. There's a special feature whereby a
1777user-installed package named _xmlplus overrides the standard
1778xmlpackage; this is intended to give the XML SIG a hook to distribute
1779backwards-compatible updates to the standard xml package.
1780
1781webbrowser - a platform-independent API to launch a web browser.
1782
1783
Guido van Rossume905e952000-09-05 12:42:46 +00001784Changed Modules
1785---------------
1786
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001787array -- new methods for array objects: count, extend, index, pop, and
1788remove
1789
1790binascii -- new functions b2a_hex and a2b_hex that convert between
1791binary data and its hex representation
1792
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001793calendar -- Many new functions that support features including control
1794over which day of the week is the first day, returning strings instead
1795of printing them. Also new symbolic constants for days of week,
1796e.g. MONDAY, ..., SUNDAY.
1797
1798cgi -- FieldStorage objects have a getvalue method that works like a
1799dictionary's get method and returns the value attribute of the object.
1800
1801ConfigParser -- The parser object has new methods has_option,
1802remove_section, remove_option, set, and write. They allow the module
1803to be used for writing config files as well as reading them.
1804
1805ftplib -- ntransfercmd(), transfercmd(), and retrbinary() all now
Guido van Rossume905e952000-09-05 12:42:46 +00001806optionally support the RFC 959 REST command.
1807
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001808gzip -- readline and readlines now accept optional size arguments
Guido van Rossume905e952000-09-05 12:42:46 +00001809
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001810httplib -- New interfaces and support for HTTP/1.1 by Greg Stein. See
1811the module doc strings for details.
Guido van Rossum830ca2a2000-09-05 15:34:16 +00001812
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001813locale -- implement getdefaultlocale for Win32 and Macintosh
1814
1815marshal -- no longer dumps core when marshaling deeply nested or
1816recursive data structures
1817
1818os -- new functions isatty, seteuid, setegid, setreuid, setregid
1819
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001820os/popen2 -- popen2/popen3/popen4 support under Windows. popen2/popen3
1821support under Unix.
1822
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001823os/pty -- support for openpty and forkpty
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001824
1825os.path -- fix semantics of os.path.commonprefix
1826
1827smtplib -- support for sending very long messages
1828
1829socket -- new function getfqdn()
1830
1831readline -- new functions to read, write and truncate history files.
1832The readline section of the library reference manual contains an
1833example.
1834
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001835select -- add interface to poll system call
1836
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001837shutil -- new copyfileobj function
1838
1839SimpleHTTPServer, CGIHTTPServer -- Fix problems with buffering in the
1840HTTP server.
1841
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001842Tkinter -- optimization of function flatten
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001843
1844urllib -- scans environment variables for proxy configuration,
Tim Peters8b092332000-09-05 20:15:25 +00001845e.g. http_proxy.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001846
1847whichdb -- recognizes dumbdbm format
Guido van Rossume905e952000-09-05 12:42:46 +00001848
1849
1850Obsolete Modules
1851----------------
1852
1853None. However note that 1.6 made a whole slew of modules obsolete:
1854stdwin, soundex, cml, cmpcache, dircache, dump, find, grep, packmail,
1855poly, zmod, strop, util, whatsound.
1856
1857
1858Changed, New, Obsolete Tools
1859----------------------------
1860
Tim Peters8b092332000-09-05 20:15:25 +00001861None.
Guido van Rossume905e952000-09-05 12:42:46 +00001862
1863
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001864C-level Changes
1865---------------
1866
1867Several cleanup jobs were carried out throughout the source code.
1868
1869All C code was converted to ANSI C; we got rid of all uses of the
1870Py_PROTO() macro, which makes the header files a lot more readable.
1871
1872Most of the portability hacks were moved to a new header file,
1873pyport.h; several other new header files were added and some old
1874header files were removed, in an attempt to create a more rational set
1875of header files. (Few of these ever need to be included explicitly;
1876they are all included by Python.h.)
1877
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001878Trent Mick ensured portability to 64-bit platforms, under both Linux
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001879and Win64, especially for the new Intel Itanium processor. Mick also
1880added large file support for Linux64 and Win64.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001881
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001882The C APIs to return an object's size have been update to consistently
1883use the form PyXXX_Size, e.g. PySequence_Size and PyDict_Size. In
1884previous versions, the abstract interfaces used PyXXX_Length and the
1885concrete interfaces used PyXXX_Size. The old names,
1886e.g. PyObject_Length, are still available for backwards compatibility
1887at the API level, but are deprecated.
1888
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001889The PyOS_CheckStack function has been implemented on Windows by
1890Fredrik Lundh. It prevents Python from failing with a stack overflow
1891on Windows.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001892
1893The GC changes resulted in creation of two new slots on object,
1894tp_traverse and tp_clear. The augmented assignment changes result in
Guido van Rossum4338a282000-09-06 13:02:08 +00001895the creation of a new slot for each in-place operator.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001896
1897The GC API creates new requirements for container types implemented in
Guido van Rossum4338a282000-09-06 13:02:08 +00001898C extension modules. See Include/objimpl.h for details.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001899
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001900PyErr_Format has been updated to automatically calculate the size of
1901the buffer needed to hold the formatted result string. This change
1902prevents crashes caused by programmer error.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001903
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001904New C API calls: PyObject_AsFileDescriptor, PyErr_WriteUnraisable.
Guido van Rossume905e952000-09-05 12:42:46 +00001905
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001906PyRun_AnyFileEx, PyRun_SimpleFileEx, PyRun_FileEx -- New functions
1907that are the same as their non-Ex counterparts except they take an
1908extra flag argument that tells them to close the file when done.
1909
1910XXX There were other API changes that should be fleshed out here.
Guido van Rossumab9d6f01998-08-10 22:01:13 +00001911
Tim Peters8b092332000-09-05 20:15:25 +00001912
1913Windows Changes
1914---------------
1915
1916New popen2/popen3/peopen4 in os module (see Changed Modules above).
1917
1918os.popen is much more usable on Windows 95 and 98. See Microsoft
1919Knowledge Base article Q150956. The Win9x workaround described there
1920is implemented by the new w9xpopen.exe helper in the root of your
1921Python installation. Note that Python uses this internally; it is not
1922a standalone program.
1923
1924Administrator privileges are no longer required to install Python
1925on Windows NT or Windows 2000. If you have administrator privileges,
1926Python's registry info will be written under HKEY_LOCAL_MACHINE.
1927Otherwise the installer backs off to writing Python's registry info
Guido van Rossum4338a282000-09-06 13:02:08 +00001928under HKEY_CURRENT_USER. The latter is sufficient for all "normal"
Tim Peters8b092332000-09-05 20:15:25 +00001929uses of Python, but will prevent some advanced uses from working
1930(for example, running a Python script as an NT service, or possibly
1931from CGI).
1932
1933[This was new in 1.6] The installer no longer runs a separate Tcl/Tk
1934installer; instead, it installs the needed Tcl/Tk files directly in the
1935Python directory. If you already have a Tcl/Tk installation, this
1936wastes some disk space (about 4 Megs) but avoids problems with
1937conflicting Tcl/Tk installations, and makes it much easier for Python
1938to ensure that Tcl/Tk can find all its files.
1939
1940[This was new in 1.6] The Windows installer now installs by default in
1941\Python20\ on the default volume, instead of \Program Files\Python-2.0\.
1942
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001943
1944Updates to the changes between 1.5.2 and 1.6
1945--------------------------------------------
1946
1947The 1.6 NEWS file can't be changed after the release is done, so here
1948is some late-breaking news:
1949
1950New APIs in locale.py: normalize(), getdefaultlocale(), resetlocale(),
1951and changes to getlocale() and setlocale().
1952
1953The new module is now enabled per default.
1954
1955It is not true that the encodings codecs cannot be used for normal
1956strings: the string.encode() (which is also present on 8-bit strings
1957!) allows using them for 8-bit strings too, e.g. to convert files from
1958cp1252 (Windows) to latin-1 or vice-versa.
1959
1960Japanese codecs are available from Tamito KAJIYAMA:
1961http://pseudo.grad.sccs.chukyo-u.ac.jp/~kajiyama/python/
1962
1963
Guido van Rossumab9d6f01998-08-10 22:01:13 +00001964======================================================================