blob: f9f1855ef1e2f071fbc0cd84cd2ea45c9bb8b18a [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
Mark Hammond2a0af792001-05-14 03:09:36 +00006- Some operating systems now support the concept of a default Unicode
7 encoding for file system operations. Notably, Windows supports 'mbcs'
8 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +00009 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +000010 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +000011
12 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +000013 functions that return filenames (such as os.listdir()) to return Python
14 string objects pre-encoded using the default file system encoding for
15 the platform. As this encoding is likely to be different from Python's
16 default encoding, converting this name to a Unicode object before passing
17 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +000018 would attempt to use its default encoding (generally ASCII) rather than
19 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +000020
Tim Petersa814db52001-05-14 07:05:58 +000021 In general, this change simply removes surprises when working with
22 Unicode and the file system, making these operations work as you expect,
23 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +000024 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +000025
Tim Peters61dff2b2001-05-08 15:43:37 +000026- Float (and complex) literals in source code were evaluated to full
27 precision only when running from a .py file; the same code loaded from a
28 .pyc (or .pyo) file could suffer numeric differences starting at about the
29 12th significant decimal digit. For example, on a machine with IEEE-754
30 floating arithmetic,
31
32 x = 9007199254740992.0
33 print long(x)
34
35 printed 9007199254740992 if run directly from .py, but 9007199254740000
36 if from a compiled (.pyc or .pyo) file. This was due to marshal using
37 str(float) instead of repr(float) when building code objects. marshal
38 now uses repr(float) instead, which should reproduce floats to full
39 machine precision (assuming the platform C float<->string I/O conversion
40 functions are of good quality).
41
42 This may cause floating-point results to change in some cases, and
43 usually for the better, but may also cause numerically unstable
44 algorithms to break.
45
Tim Peters2f228e72001-05-13 00:19:31 +000046- The implementation of dicts suffers fewer collisions, which has speed
47 benefits. However, the order in which dict entries appear in dict.keys(),
48 dict.values() and dict.items() may differ from previous releases for a
49 given dict. Nothing is defined about this order, so no program should
50 rely on it. Nevertheless, it's easy to write test cases that rely on the
51 order by accident, typically because of printing the str() or repr() of a
52 dict to an "expected results" file. See Lib/test/test_support.py's new
53 sortdict(dict) function for a simple way to display a dict in sorted
54 order.
55
Guido van Rossum10315822001-05-01 20:54:30 +000056- Dictionary objects now support the "in" operator: "x in dict" means
57 the same as dict.has_key(x).
58
59- Iterators were added; this is a generalized way of providing values
60 to a for loop. See PEP 234. There's a new built-in function iter()
61 to return an iterator. There's a new protocol to get the next value
62 from an iterator using the next() method (in Python) or the
63 tp_iternext slot (in C). There's a new protocol to get iterators
64 using the __iter__() method (in Python) or the tp_iter slot (in C).
65 Iterating (i.e. a for loop) over a dictionary generates its keys.
66 Iterating over a file generates its lines.
67
Tim Petersf553f892001-05-01 20:45:31 +000068- The following functions were generalized to work nicely with iterator
69 arguments:
Tim Peterse63415e2001-05-08 04:38:29 +000070 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +000071 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
72 max(), min()
Tim Petersde9725f2001-05-05 10:06:17 +000073 .join() method of strings
Tim Peters75f8e352001-05-05 11:33:43 +000074 'x in y' and 'x not in y' (PySequence_Contains() in C API)
75 operator.countOf() (PySequence_Count() in C API)
Tim Peters75f8e352001-05-05 11:33:43 +000076
Tim Petersd85e1022001-05-11 21:51:48 +000077- Accessing module attributes is significantly faster (for example,
78 random.random or os.path or yourPythonModule.yourAttribute).
79
Tim Peterse63415e2001-05-08 04:38:29 +000080- Comparing dictionary objects via == and != is faster, and now works even
81 if the keys and values don't support comparisons other than ==.
82
Tim Peters95bf9392001-05-10 08:32:44 +000083- Comparing dictionaries in ways other than == and != is slower: there were
84 insecurities in the dict comparison implementation that could cause Python
85 to crash if the element comparison routines for the dict keys and/or
86 values mutated the dicts. Making the code bulletproof slowed it down.
87
Tim Petersa814db52001-05-14 07:05:58 +000088Library
89
Guido van Rossum2e0a6542001-05-15 02:14:44 +000090- strop is now *really* obsolete (this was announced before with 1.6),
91 and issues DeprecationWarning when used (except for the four items
92 that are still imported into string.py).
93
Tim Petersa814db52001-05-14 07:05:58 +000094- Cookie.py now sorts key+value pairs by key in output strings.
95
96- pprint.isrecursive(object) didn't correctly identify recursive objects.
97 Now it does.
98
Tim Peters95b3f782001-05-14 18:39:41 +000099- pprint functions now much faster for large containers (tuple, list, dict).
100
Tim Petersa814db52001-05-14 07:05:58 +0000101Tests
102
103- New test_mutants.py runs dict comparisons where the key and value
104 comparison operators mutute the dicts randomly during comparison. This
105 rapidly causes Python to crash under earlier releases (not for the faint
106 of heart: it can also cause Win9x to freeze or reboot!).
107
108- New test_pprint.py verfies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +0000109 pprint.isreadable() return sensible results. Also verifies that simple
110 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +0000111
Tim Peters58e0a8c2001-05-14 22:32:33 +0000112New platforms
113
114- Python should compile and run out of the box using the Borland C
115 compiler (under Windows), thanks to Stephen Hansen.
Tim Petersf553f892001-05-01 20:45:31 +0000116
Guido van Rossumffe13be2001-04-16 18:46:45 +0000117What's New in Python 2.1 (final)?
118=================================
119
120We only changed a few things since the last release candidate, all in
121Python library code:
122
123- A bug in the locale module was fixed that affected locales which
124 define no grouping for numeric formatting.
125
126- A few bugs in the weakref module's implementations of weak
127 dictionaries (WeakValueDictionary and WeakKeyDictionary) were fixed,
128 and the test suite was updated to check for these bugs.
129
130- An old bug in the os.path.walk() function (introduced in Python
131 2.0!) was fixed: a non-existent file would cause an exception
132 instead of being ignored.
133
134- Fixed a few bugs in the new symtable module found by Neil Norwitz's
135 PyChecker.
136
137
Guido van Rossum5b08f132001-04-16 02:05:23 +0000138What's New in Python 2.1c2?
139===========================
Barry Warsaw11e89c72001-04-11 20:37:57 +0000140
Guido van Rossum5b08f132001-04-16 02:05:23 +0000141A flurry of small changes, and one showstopper fixed in the nick of
142time made it necessary to release another release candidate. The list
143here is the *complete* list of patches (except version updates):
Guido van Rossum4fb60362001-04-13 00:46:14 +0000144
Guido van Rossum5b08f132001-04-16 02:05:23 +0000145Core
Guido van Rossum4fb60362001-04-13 00:46:14 +0000146
Guido van Rossum5b08f132001-04-16 02:05:23 +0000147- Tim discovered a nasty bug in the dictionary code, caused by
148 PyDict_Next() calling dict_resize(), and the GC code's use of
149 PyDict_Next() violating an assumption in dict_items(). This was
150 fixed with considerable amounts of band-aid, but the net effect is a
151 saner and more robust implementation.
152
153- Made a bunch of symbols static that were accidentally global.
154
155Build and Ports
156
157- The setup.py script didn't check for a new enough version of zlib
158 (1.1.3 is needed). Now it does.
159
160- Changed "make clean" target to also remove shared libraries.
161
162- Added a more general warning about the SGI Irix optimizer to README.
163
164Library
165
166- Fix a bug in urllib.basejoin("http://host", "../file.html") which
167 omitted the slash between host and file.html.
168
169- The mailbox module's _Mailbox class contained a completely broken
170 and undocumented seek() method. Ripped it out.
171
172- Fixed a bunch of typos in various library modules (urllib2, smtpd,
173 sgmllib, netrc, chunk) found by Neil Norwitz's PyChecker.
174
175- Fixed a few last-minute bugs in unittest.
176
177Extensions
178
179- Reverted the patch to the OpenSSL code in socketmodule.c to support
180 RAND_status() and the EGD, and the subsequent patch that tried to
181 fix it for pre-0.9.5 versions; the problem with the patch is that on
182 some systems it issues a warning whenever socket is imported, and
183 that's unacceptable.
184
185Tests
186
187- Fixed the pickle tests to work with "import test.test_pickle".
188
189- Tweaked test_locale.py to actually run the test Windows.
190
191- In distutils/archive_util.py, call zipfile.ZipFile() with mode "w",
192 not "wb" (which is not a valid mode at all).
193
194- Fix pstats browser crashes. Import readline if it exists to make
195 the user interface nicer.
196
197- Add "import thread" to the top of test modules that import the
198 threading module (test_asynchat and test_threadedtempfile). This
199 prevents test failures caused by a broken threading module resulting
200 from a previously caught failed import.
201
202- Changed test_asynchat.py to set the SO_REUSEADDR option; this was
203 needed on some platforms (e.g. Solaris 8) when the tests are run
204 twice in succession.
205
206- Skip rather than fail test_sunaudiodev if no audio device is found.
207
208
209What's New in Python 2.1c1?
210===========================
211
212This list was significantly updated when 2.1c2 was released; the 2.1c1
213release didn't mention most changes that were actually part of 2.1c1:
214
215Legal
216
217- Copyright was assigned to the Python Software Foundation (PSF) and a
218 PSF license (very similar to the CNRI license) was added.
219
220- The CNRI copyright notice was updated to include 2001.
221
222Core
Barry Warsaw11e89c72001-04-11 20:37:57 +0000223
Guido van Rossumc9932722001-04-12 02:31:27 +0000224- After a public outcry, assignment to __debug__ is no longer illegal;
225 instead, a warning is issued. It will become illegal in 2.2.
226
Guido van Rossum5b08f132001-04-16 02:05:23 +0000227- Fixed a core dump with "%#x" % 0, and changed the semantics so that
228 "%#x" now always prepends "0x", even if the value is zero.
229
230- Fixed some nits in the bytecode compiler.
231
232- Fixed core dumps when calling certain kinds of non-functions.
233
234- Fixed various core dumps caused by reference count bugs.
235
236Build and Ports
237
238- Use INSTALL_SCRIPT to install script files.
239
Guido van Rossum34d37dc2001-04-11 21:03:32 +0000240- New port: SCO Unixware 7, by Billy G. Allie.
241
Guido van Rossum5b08f132001-04-16 02:05:23 +0000242- Updated RISCOS port.
243
244- Updated BeOS port and notes.
245
246- Various other porting problems resolved.
247
248Library
249
250- The TERMIOS and SOCKET modules are now truly obsolete and
251 unnecessary. Their symbols are incorporated in the termios and
252 socket modules.
253
254- Fixed some 64-bit bugs in pickle, cPickle, and struct, and added
255 better tests for pickling.
256
257- threading: make Condition.wait() robust against KeyboardInterrupt.
258
259- zipfile: add support to zipfile to support opening an archive
260 represented by an open file rather than a file name. Fix bug where
261 the archive was not properly closed. Fixed a bug in this bugfix
262 where flush() was called for a read-only file.
263
264- imputil: added an uninstall() method to the ImportManager.
265
266- Canvas: fixed bugs in lower() and tkraise() methods.
267
268- SocketServer: API change (added overridable close_request() method)
269 so that the TCP server can explicitly close the request.
270
271- pstats: Eric Raymond added a simple interactive statistics browser,
272 invoked when the module is run as a script.
273
274- locale: fixed a problem in format().
275
276- webbrowser: made it work when the BROWSER environment variable has a
277 value like "/usr/bin/netscape". Made it auto-detect Konqueror for
278 KDE 2. Fixed some other nits.
279
280- unittest: changes to allow using a different exception than
281 AssertionError, and added a few more function aliases. Some other
282 small changes.
283
284- urllib, urllib2: fixed redirect problems and a coupleof other nits.
285
286- asynchat: fixed a critical bug in asynchat that slipped through the
287 2.1b2 release. Fixed another rare bug.
288
289- Fix some unqualified except: clauses (always a bad code example).
290
291XML
292
293- pyexpat: new API get_version_string().
294
295- Fixed some minidom bugs.
296
297Extensions
298
299- Fixed a core dump in _weakref. Removed the weakref.mapping()
300 function (it adds nothing to the API).
301
302- Rationalized the use of header files in the readline module, to make
303 it compile (albeit with some warnings) with the very recent readline
304 4.2, without breaking for earlier versions.
305
306- Hopefully fixed a buffering problem in linuxaudiodev.
307
308- Attempted a fix to make the OpenSSL support in the socket module
309 work again with pre-0.9.5 versions of OpenSSL.
310
311Tests
312
313- Added a test case for asynchat and asyncore.
314
315- Removed coupling between tests where one test failing could break
316 another.
317
318Tools
319
320- Ping added an interactive help browser to pydoc, fixed some nits
321 in the rest of the pydoc code, and added some features to his
322 inspect module.
323
324- An updated python-mode.el version 4.1 which integrates Ken
325 Manheimer's pdbtrack.el. This makes debugging Python code via pdb
326 much nicer in XEmacs and Emacs. When stepping through your program
327 with pdb, in either the shell window or the *Python* window, the
328 source file and line will be tracked by an arrow. Very cool!
329
330- IDLE: syntax warnings in interactive mode are changed into errors.
331
332- Some improvements to Tools/webchecker (ignore some more URL types,
Tim Peters0e57abf2001-05-02 07:39:38 +0000333 follow some more links).
Guido van Rossum5b08f132001-04-16 02:05:23 +0000334
335- Brought the Tools/compiler package up to date.
Guido van Rossum34d37dc2001-04-11 21:03:32 +0000336
Barry Warsaw11e89c72001-04-11 20:37:57 +0000337
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000338What's New in Python 2.1 beta 2?
339================================
340
Guido van Rossum053ae352001-03-22 14:17:21 +0000341(Unlisted are many fixed bugs, more documentation, etc.)
342
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000343Core language, builtins, and interpreter
344
Guido van Rossum053ae352001-03-22 14:17:21 +0000345- The nested scopes work (enabled by "from __future__ import
346 nested_scopes") is completed; in particular, the future now extends
347 into code executed through exec, eval() and execfile(), and into the
348 interactive interpreter.
349
350- When calling a base class method (e.g. BaseClass.__init__(self)),
351 this is now allowed even if self is not strictly spoken a class
352 instance (e.g. when using metaclasses or the Don Beaudry hook).
353
354- Slice objects are now comparable but not hashable; this prevents
355 dict[:] from being accepted but meaningless.
356
357- Complex division is now calculated using less braindead algorithms.
358 This doesn't change semantics except it's more likely to give useful
359 results in extreme cases. Complex repr() now uses full precision
360 like float repr().
361
362- sgmllib.py now calls handle_decl() for simple <!...> declarations.
363
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000364- It is illegal to assign to the name __debug__, which is set when the
365 interpreter starts. It is effectively a compile-time constant.
366
367- A warning will be issued if a global statement for a variable
368 follows a use or assignment of that variable.
369
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000370Standard library
371
Guido van Rossum053ae352001-03-22 14:17:21 +0000372- unittest.py, a unit testing framework by Steve Purcell (PyUNIT,
373 inspired by JUnit), is now part of the standard library. You now
374 have a choice of two testing frameworks: unittest requires you to
375 write testcases as separate code, doctest gathers them from
376 docstrings. Both approaches have their advantages and
377 disadvantages.
378
379- A new module Tix was added, which wraps the Tix extension library
380 for Tk. With that module, it is not necessary to statically link
381 Tix with _tkinter, since Tix will be loaded with Tcl's "package
382 require" command. See Demo/tix/.
383
384- tzparse.py is now obsolete.
385
386- In gzip.py, the seek() and tell() methods are removed -- they were
387 non-functional anyway, and it's better if callers can test for their
388 existence with hasattr().
389
390Python/C API
391
392- PyDict_Next(): it is now safe to call PyDict_SetItem() with a key
393 that's already in the dictionary during a PyDict_Next() iteration.
394 This used to fail occasionally when a dictionary resize operation
395 could be triggered that would rehash all the keys. All other
396 modifications to the dictionary are still off-limits during a
397 PyDict_Next() iteration!
398
399- New extended APIs related to passing compiler variables around.
400
401- New abstract APIs PyObject_IsInstance(), PyObject_IsSubclass()
402 implement isinstance() and issubclass().
403
404- Py_BuildValue() now has a "D" conversion to create a Python complex
405 number from a Py_complex C value.
Martin v. Löwis0411f6f2001-03-21 08:01:39 +0000406
Fred Drake4e262a92001-03-22 18:26:47 +0000407- Extensions types which support weak references must now set the
408 field allocated for the weak reference machinery to NULL themselves;
409 this is done to avoid the cost of checking each object for having a
410 weakly referencable type in PyObject_INIT(), since most types are
411 not weakly referencable.
412
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000413- PyFrame_FastToLocals() and PyFrame_LocalsToFast() copy bindings for
414 free variables and cell variables to and from the frame's f_locals.
415
416- Variants of several functions defined in pythonrun.h have been added
417 to support the nested_scopes future statement. The variants all end
418 in Flags and take an extra argument, a PyCompilerFlags *; examples:
419 PyRun_AnyFileExFlags(), PyRun_InteractiveLoopFlags(). These
420 variants may be removed in Python 2.2, when nested scopes are
Tim Peters0e57abf2001-05-02 07:39:38 +0000421 mandatory.
Jeremy Hyltonf626db72001-03-23 14:18:27 +0000422
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000423Distutils
424
425- the sdist command now writes a PKG-INFO file, as described in PEP 241,
426 into the release tree.
427
Tim Peters0e57abf2001-05-02 07:39:38 +0000428- several enhancements to the bdist_wininst command from Thomas Heller
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000429 (an uninstaller, more customization of the installer's display)
430
431- from Jack Jansen: added Mac-specific code to generate a dialog for
432 users to specify the command-line (because providing a command-line with
Tim Peters0e57abf2001-05-02 07:39:38 +0000433 MacPython is awkward). Jack also made various fixes for the Mac
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000434 and the Metrowerks compiler.
Tim Peters0e57abf2001-05-02 07:39:38 +0000435
436- added 'platforms' and 'keywords' to the set of metadata that can be
437 specified for a distribution.
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +0000438
439- applied patches from Jason Tishler to make the compiler class work with
440 Cygwin.
441
442
Tim Peters2fe289a2001-03-01 22:19:38 +0000443What's New in Python 2.1 beta 1?
444================================
Tim Petersd66595f2001-02-04 03:09:53 +0000445
446Core language, builtins, and interpreter
447
Guido van Rossum9d0fbde2001-03-02 14:00:32 +0000448- Following an outcry from the community about the amount of code
449 broken by the nested scopes feature introduced in 2.1a2, we decided
450 to make this feature optional, and to wait until Python 2.2 (or at
451 least 6 months) to make it standard. The option can be enabled on a
452 per-module basis by adding "from __future__ import nested_scopes" at
453 the beginning of a module (before any other statements, but after
454 comments and an optional docstring). See PEP 236 (Back to the
455 __future__) for a description of the __future__ statement. PEP 227
456 (Statically Nested Scopes) has been updated to reflect this change,
457 and to clarify the semantics in a number of endcases.
458
459- The nested scopes code, when enabled, has been hardened, and most
460 bugs and memory leaks in it have been fixed.
461
462- Compile-time warnings are now generated for a number of conditions
463 that will break or change in meaning when nested scopes are enabled:
464
465 - Using "from...import *" or "exec" without in-clause in a function
466 scope that also defines a lambda or nested function with one or
467 more free (non-local) variables. The presence of the import* or
468 bare exec makes it impossible for the compiler to determine the
469 exact set of local variables in the outer scope, which makes it
470 impossible to determine the bindings for free variables in the
471 inner scope. To avoid the warning about import *, change it into
472 an import of explicitly name object, or move the import* statement
473 to the global scope; to avoid the warning about bare exec, use
474 exec...in... (a good idea anyway -- there's a possibility that
475 bare exec will be deprecated in the future).
476
477 - Use of a global variable in a nested scope with the same name as a
478 local variable in a surrounding scope. This will change in
479 meaning with nested scopes: the name in the inner scope will
480 reference the variable in the outer scope rather than the global
481 of the same name. To avoid the warning, either rename the outer
482 variable, or use a global statement in the inner function.
483
Neil Schemenauera35c6882001-02-27 04:45:05 +0000484- An optional object allocator has been included. This allocator is
485 optimized for Python objects and should be faster and use less memory
486 than the standard system allocator. It is not enabled by default
487 because of possible thread safety problems. The allocator is only
488 protected by the Python interpreter lock and it is possible that some
489 extension modules require a thread safe allocator. The object
490 allocator can be enabled by providing the "--with-pymalloc" option to
491 configure.
492
Tim Petersd66595f2001-02-04 03:09:53 +0000493Standard library
494
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000495- pyexpat now detects the expat version if expat.h defines it. A
496 number of additional handlers are provided, which are only available
497 since expat 1.95. In addition, the methods SetParamEntityParsing and
498 GetInputContext of Parser objects are available with 1.95.x
499 only. Parser objects now provide the ordered_attributes and
500 specified_attributes attributes. A new module expat.model was added,
501 which offers a number of additional constants if 1.95.x is used.
502
503- xml.dom offers the new functions registerDOMImplementation and
504 getDOMImplementation.
505
506- xml.dom.minidom offers a toprettyxml method. A number of DOM
507 conformance issues have been resolved. In particular, Element now
508 has an hasAttributes method, and the handling of namespaces was
509 improved.
510
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +0000511- Ka-Ping Yee contributed two new modules: inspect.py, a module for
512 getting information about live Python code, and pydoc.py, a module
513 for interactively converting docstrings to HTML or text.
514 Tools/scripts/pydoc, which is now automatically installed into
Tim Peters1eff7962001-03-01 02:31:33 +0000515 <prefix>/bin, uses pydoc.py to display documentation; try running
Guido van Rossume3955a82001-03-02 14:05:59 +0000516 "pydoc -h" for instructions. "pydoc -g" pops up a small GUI that
517 lets you browse the module docstrings using a web browser.
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +0000518
Tim Peters1eff7962001-03-01 02:31:33 +0000519- New library module difflib.py, primarily packaging the SequenceMatcher
520 class at the heart of the popular ndiff.py file-comparison tool.
521
522- doctest.py (a framework for verifying Python code examples in docstrings)
523 is now part of the std library.
524
Tim Petersd66595f2001-02-04 03:09:53 +0000525Windows changes
526
Guido van Rossume3955a82001-03-02 14:05:59 +0000527- A new entry in the Start menu, "Module Docs", runs "pydoc -g" -- a
528 small GUI that lets you browse the module docstrings using your
529 default web browser.
530
Tim Peters1eff7962001-03-01 02:31:33 +0000531- Import is now case-sensitive. PEP 235 (Import on Case-Insensitive
532 Platforms) is implemented. See
533
534 http://python.sourceforge.net/peps/pep-0235.html
535
536 for full details, especially the "Current Lower-Left Semantics" section.
537 The new Windows import rules are simpler than before:
538
539 A. If the PYTHONCASEOK environment variable exists, same as
540 before: silently accept the first case-insensitive match of any
541 kind; raise ImportError if none found.
542
543 B. Else search sys.path for the first case-sensitive match; raise
544 ImportError if none found.
545
546 The same rules have been implented on other platforms with case-
547 insensitive but case-preserving filesystems too (including Cygwin, and
548 several flavors of Macintosh operating systems).
Tim Petersd66595f2001-02-04 03:09:53 +0000549
Tim Peters25a9ce32001-02-19 07:06:36 +0000550- winsound module: Under Win9x, winsound.Beep() now attempts to simulate
551 what it's supposed to do (and does do under NT and 2000) via direct
552 port manipulation. It's unknown whether this will work on all systems,
Tim Peters1eff7962001-03-01 02:31:33 +0000553 but it does work on my Win98SE systems now and was known to be useless on
Tim Peters25a9ce32001-02-19 07:06:36 +0000554 all Win9x systems before.
555
Tim Peters1eff7962001-03-01 02:31:33 +0000556- Build: Subproject _test (effectively) renamed to _testcapi.
557
Tim Peters2fe289a2001-03-01 22:19:38 +0000558New platforms
559
560- 2.1 should compile and run out of the box under MacOS X, even using HFS+.
561 Thanks to Steven Majewski!
562
563- 2.1 should compile and run out of the box on Cygwin. Thanks to Jason
564 Tishler!
565
Guido van Rossum9089b272001-03-02 06:49:50 +0000566- 2.1 contains new files and patches for RISCOS, thanks to Dietmar
567 Schwertberger! See RISCOS/README for more information -- it seems
568 that because of the bizarre filename conventions on RISCOS, no port
569 to that platform is easy. Note that the new variable os.endsep is
570 silently supported in order to make life easier on this platform,
571 but we don't advertise it because it's not worth for most folks to
572 care about RISCOS portability.
573
Tim Peters25a9ce32001-02-19 07:06:36 +0000574
Tim Petersd7b5e882001-01-25 03:36:26 +0000575What's New in Python 2.1 alpha 2?
576=================================
Tim Peters40ead762001-01-27 05:35:26 +0000577
Tim Petersd7b5e882001-01-25 03:36:26 +0000578Core language, builtins, and interpreter
579
Jeremy Hylton4589bd82001-02-01 20:38:45 +0000580- Scopes nest. If a name is used in a function or class, but is not
581 local, the definition in the nearest enclosing function scope will
582 be used. One consequence of this change is that lambda statements
583 could reference variables in the namespaces where the lambda is
584 defined. In some unusual cases, this change will break code.
585
586 In all previous version of Python, names were resolved in exactly
587 three namespaces -- the local namespace, the global namespace, and
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000588 the builtin namespace. According to this old definition, if a
Jeremy Hylton4589bd82001-02-01 20:38:45 +0000589 function A is defined within a function B, the names bound in B are
590 not visible in A. The new rules make names bound in B visible in A,
591 unless A contains a name binding that hides the binding in B.
592
593 Section 4.1 of the reference manual describes the new scoping rules
594 in detail. The test script in Lib/test/test_scope.py demonstrates
595 some of the effects of the change.
596
597 The new rules will cause existing code to break if it defines nested
598 functions where an outer function has local variables with the same
599 name as globals or builtins used by the inner function. Example:
600
601 def munge(str):
602 def helper(x):
603 return str(x)
604 if type(str) != type(''):
605 str = helper(str)
606 return str.strip()
607
608 Under the old rules, the name str in helper() is bound to the
609 builtin function str(). Under the new rules, it will be bound to
610 the argument named str and an error will occur when helper() is
611 called.
612
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000613- The compiler will report a SyntaxError if "from ... import *" occurs
614 in a function or class scope. The language reference has documented
615 that this case is illegal, but the compiler never checked for it.
616 The recent introduction of nested scope makes the meaning of this
617 form of name binding ambiguous. In a future release, the compiler
618 may allow this form when there is no possibility of ambiguity.
619
Tim Peters40ead762001-01-27 05:35:26 +0000620- repr(string) is easier to read, now using hex escapes instead of octal,
621 and using \t, \n and \r instead of \011, \012 and \015 (respectively):
622
623 >>> "\texample \r\n" + chr(0) + chr(255)
624 '\texample \r\n\x00\xff' # in 2.1
625 '\011example \015\012\000\377' # in 2.0
626
Moshe Zadka6af0ce02001-01-29 06:41:00 +0000627- Functions are now compared and hashed by identity, not by value, since
628 the func_code attribute is writable.
629
Fred Drakefb9d7122001-02-01 20:00:40 +0000630- Weak references (PEP 205) have been added. This involves a few
631 changes in the core, an extension module (_weakref), and a Python
632 module (weakref). The weakref module is the public interface. It
633 includes support for "explicit" weak references, proxy objects, and
634 mappings with weakly held values.
635
Jeremy Hylton0072d5a2001-02-01 22:53:15 +0000636- A 'continue' statement can now appear in a try block within the body
637 of a loop. It is still not possible to use continue in a finally
Tim Peters9ea17ac2001-02-02 05:57:15 +0000638 clause.
Jeremy Hylton0072d5a2001-02-01 22:53:15 +0000639
Tim Petersd7b5e882001-01-25 03:36:26 +0000640Standard library
641
Barry Warsaw30dbd142001-01-31 22:14:01 +0000642- mailbox.py now has a new class, PortableUnixMailbox which is
643 identical to UnixMailbox but uses a more portable scheme for
644 determining From_ separators. Also, the constructors for all the
645 classes in this module have a new optional `factory' argument, which
646 is a callable used when new message classes must be instantiated by
647 the next() method.
648
Tim Petersd7b5e882001-01-25 03:36:26 +0000649- random.py is now self-contained, and offers all the functionality of
650 the now-deprecated whrandom.py. See the docs for details. random.py
651 also supports new functions getstate() and setstate(), for saving
Tim Petersd52269b2001-01-25 06:23:18 +0000652 and restoring the internal state of the generator; and jumpahead(n),
653 for quickly forcing the internal state to be the same as if n calls to
654 random() had been made. The latter is particularly useful for multi-
655 threaded programs, creating one instance of the random.Random() class for
656 each thread, then using .jumpahead() to force each instance to use a
657 non-overlapping segment of the full period.
Tim Petersd7b5e882001-01-25 03:36:26 +0000658
Tim Peters0de88fc2001-02-01 04:59:18 +0000659- random.py's seed() function is new. For bit-for-bit compatibility with
660 prior releases, use the whseed function instead. The new seed function
661 addresses two problems: (1) The old function couldn't produce more than
662 about 2**24 distinct internal states; the new one about 2**45 (the best
663 that can be done in the Wichmann-Hill generator). (2) The old function
664 sometimes produced identical internal states when passed distinct
665 integers, and there was no simple way to predict when that would happen;
666 the new one guarantees to produce distinct internal states for all
667 arguments in [0, 27814431486576L).
668
Jeremy Hylton4c4fda02001-02-02 03:29:24 +0000669- The socket module now supports raw packets on Linux. The socket
670 family is AF_PACKET.
671
Tim Peters9ea17ac2001-02-02 05:57:15 +0000672- test_capi.py is a start at running tests of the Python C API. The tests
673 are implemented by the new Modules/_testmodule.c.
674
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000675- A new extension module, _symtable, provides provisional access to the
676 internal symbol table used by the Python compiler. A higher-level
677 interface will be added on top of _symtable in a future release.
678
Andrew M. Kuchlingdebc3522001-02-22 15:53:21 +0000679- Removed the obsolete soundex module.
680
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000681- xml.dom.minidom now uses the standard DOM exceptions. Node supports
682 the isSameNode method; NamedNodeMap the get method.
683
684- xml.sax.expatreader supports the lexical handler property; it
685 generates comment, startCDATA, and endCDATA events.
686
Tim Petersee826f82001-01-31 19:39:44 +0000687Windows changes
688
689- Build procedure: the zlib project is built in a different way that
690 ensures the zlib header files used can no longer get out of synch with
Tim Peters9ea17ac2001-02-02 05:57:15 +0000691 the zlib binary used. See PCbuild\readme.txt for details. Your old
692 zlib-related directories can be deleted; you'll need to download fresh
693 source for zlib and unpack it into a new directory.
Tim Petersee826f82001-01-31 19:39:44 +0000694
Tim Peters9ea17ac2001-02-02 05:57:15 +0000695- Build: New subproject _test for the benefit of test_capi.py (see above).
696
Tim Petersb16c56f2001-02-02 21:24:51 +0000697- Build: New subproject _symtable, for new DLL _symtable.pyd (a nascent
698 interface to some Python compiler internals).
699
700- Build: Subproject ucnhash is gone, since the code was folded into the
Tim Peters9ea17ac2001-02-02 05:57:15 +0000701 unicodedata subproject.
Tim Petersd7b5e882001-01-25 03:36:26 +0000702
Tim Petersa3a3a032000-11-30 05:22:44 +0000703What's New in Python 2.1 alpha 1?
704=================================
705
706Core language, builtins, and interpreter
707
Marc-André Lemburgebb195b2001-01-20 10:34:52 +0000708- There is a new Unicode companion to the PyObject_Str() API
709 called PyObject_Unicode(). It behaves in the same way as the
710 former, but assures that the returned value is an Unicode object
711 (applying the usual coercion if necessary).
Marc-André Lemburgad7c98e2001-01-17 17:09:53 +0000712
Guido van Rossumf98eda02001-01-17 15:54:45 +0000713- The comparison operators support "rich comparison overloading" (PEP
714 207). C extension types can provide a rich comparison function in
715 the new tp_richcompare slot in the type object. The cmp() function
716 and the C function PyObject_Compare() first try the new rich
717 comparison operators before trying the old 3-way comparison. There
718 is also a new C API PyObject_RichCompare() (which also falls back on
719 the old 3-way comparison, but does not constrain the outcome of the
720 rich comparison to a Boolean result).
721
722 The rich comparison function takes two objects (at least one of
723 which is guaranteed to have the type that provided the function) and
724 an integer indicating the opcode, which can be Py_LT, Py_LE, Py_EQ,
725 Py_NE, Py_GT, Py_GE (for <, <=, ==, !=, >, >=), and returns a Python
726 object, which may be NotImplemented (in which case the tp_compare
727 slot function is used as a fallback, if defined).
728
729 Classes can overload individual comparison operators by defining one
730 or more of the methods__lt__, __le__, __eq__, __ne__, __gt__,
Guido van Rossuma88479f2001-01-18 14:28:08 +0000731 __ge__. There are no explicit "reflected argument" versions of
732 these; instead, __lt__ and __gt__ are each other's reflection,
733 likewise for__le__ and __ge__; __eq__ and __ne__ are their own
734 reflection (similar at the C level). No other implications are
735 made; in particular, Python does not assume that == is the Boolean
736 inverse of !=, or that < is the Boolean inverse of >=. This makes
737 it possible to define types with partial orderings.
Guido van Rossumf98eda02001-01-17 15:54:45 +0000738
739 Classes or types that want to implement (in)equality tests but not
740 the ordering operators (i.e. unordered types) should implement ==
741 and !=, and raise an error for the ordering operators.
742
Guido van Rossuma88479f2001-01-18 14:28:08 +0000743 It is possible to define types whose rich comparison results are not
Guido van Rossumf98eda02001-01-17 15:54:45 +0000744 Boolean; e.g. a matrix type might want to return a matrix of bits
745 for A < B, giving elementwise comparisons. Such types should ensure
746 that any interpretation of their value in a Boolean context raises
747 an exception, e.g. by defining __nonzero__ (or the tp_nonzero slot
748 at the C level) to always raise an exception.
749
Guido van Rossuma88479f2001-01-18 14:28:08 +0000750- Complex numbers use rich comparisons to define == and != but raise
751 an exception for <, <=, > and >=. Unfortunately, this also means
752 that cmp() of two complex numbers raises an exception when the two
753 numbers differ. Since it is not mathematically meaningful to compare
754 complex numbers except for equality, I hope that this doesn't break
755 too much code.
756
Tim Peters3389f192001-02-18 08:48:49 +0000757- The outcome of comparing non-numeric objects of different types is
Tim Peters14495852001-02-18 08:28:33 +0000758 not defined by the language, other than that it's arbitrary but
759 consistent (see the Reference Manual). An implementation detail changed
760 in 2.1a1 such that None now compares less than any other object. Code
761 relying on this new behavior (like code that relied on the previous
762 behavior) does so at its own risk.
763
Barry Warsaw573b5412001-01-15 20:43:18 +0000764- Functions and methods now support getting and setting arbitrarily
765 named attributes (PEP 232). Functions have a new __dict__
766 (a.k.a. func_dict) which hold the function attributes. Methods get
767 and set attributes on their underlying im_func. It is a TypeError
768 to set an attribute on a bound method.
769
Guido van Rossum051e3352001-01-15 19:11:10 +0000770- The xrange() object implementation has been improved so that
771 xrange(sys.maxint) can be used on 64-bit platforms. There's still a
772 limitation that in this case len(xrange(sys.maxint)) can't be
773 calculated, but the common idiom "for i in xrange(sys.maxint)" will
774 work fine as long as the index i doesn't actually reach 2**31.
775 (Python uses regular ints for sequence and string indices; fixing
776 that is much more work.)
777
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000778- Two changes to from...import:
779
Guido van Rossumba381232001-02-03 15:06:40 +0000780 1) "from M import X" now works even if (after loading module M)
781 sys.modules['M'] is not a real module; it's basically a getattr()
782 operation with AttributeError exceptions changed into ImportError.
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000783
784 2) "from M import *" now looks for M.__all__ to decide which names to
785 import; if M.__all__ doesn't exist, it uses M.__dict__.keys() but
786 filters out names starting with '_' as before. Whether or not
787 __all__ exists, there's no restriction on the type of M.
788
Guido van Rossumf61f1662001-01-10 20:13:55 +0000789- File objects have a new method, xreadlines(). This is the fastest
790 way to iterate over all lines in a file:
791
792 for line in file.xreadlines():
793 ...do something to line...
794
795 See the xreadlines module (mentioned below) for how to do this for
796 other file-like objects.
797
798- Even if you don't use file.xreadlines(), you may expect a speedup on
799 line-by-line input. The file.readline() method has been optimized
Tim Petersf29b64d2001-01-15 06:33:19 +0000800 quite a bit in platform-specific ways: on systems (like Linux) that
801 support flockfile(), getc_unlocked(), and funlockfile(), those are
802 used by default. On systems (like Windows) without getc_unlocked(),
803 a complicated (but still thread-safe) method using fgets() is used by
804 default.
805
Tim Petersd52269b2001-01-25 06:23:18 +0000806 You can force use of the fgets() method by #define'ing
807 USE_FGETS_IN_GETLINE at build time (it may be faster than
Tim Petersf29b64d2001-01-15 06:33:19 +0000808 getc_unlocked()).
809
Tim Petersd52269b2001-01-25 06:23:18 +0000810 You can force fgets() not to be used by #define'ing
811 DONT_USE_FGETS_IN_GETLINE (this is the first thing to try if std test
Tim Petersf29b64d2001-01-15 06:33:19 +0000812 test_bufio.py fails -- and let us know if it does!).
813
814- In addition, the fileinput module, while still slower than the other
815 methods on most platforms, has been sped up too, by using
816 file.readlines(sizehint).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000817
818- Support for run-time warnings has been added, including a new
819 command line option (-W) to specify the disposition of warnings.
820 See the description of the warnings module below.
821
822- Extensive changes have been made to the coercion code. This mostly
823 affects extension modules (which can now implement mixed-type
824 numerical operators without having to use coercion), but
825 occasionally, in boundary cases the coercion semantics have changed
826 subtly. Since this was a terrible gray area of the language, this
Guido van Rossumae72d872001-01-11 15:00:14 +0000827 is considered an improvement. Also note that __rcmp__ is no longer
Guido van Rossumf61f1662001-01-10 20:13:55 +0000828 supported -- instead of calling __rcmp__, __cmp__ is called with
Guido van Rossuma88479f2001-01-18 14:28:08 +0000829 reflected arguments.
Guido van Rossumf61f1662001-01-10 20:13:55 +0000830
Guido van Rossumf98eda02001-01-17 15:54:45 +0000831- In connection with the coercion changes, a new built-in singleton
832 object, NotImplemented is defined. This can be returned for
833 operations that wish to indicate they are not implemented for a
834 particular combination of arguments. From C, this is
835 Py_NotImplemented.
836
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000837- The interpreter accepts now bytecode files on the command line even
838 if they do not have a .pyc or .pyo extension. On Linux, after executing
839
Martin v. Löwise214baa2001-02-04 22:37:56 +0000840import imp,sys,string
841magic = string.join(["\\x%.2x" % ord(c) for c in imp.get_magic()],"")
842reg = ':pyc:M::%s::%s:' % (magic, sys.executable)
843open("/proc/sys/fs/binfmt_misc/register","wb").write(reg)
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000844
845 any byte code file can be used as an executable (i.e. as an argument
846 to execve(2)).
847
Tim Peters9940b802000-12-01 07:59:35 +0000848- %[xXo] formats of negative Python longs now produce a sign
Tim Petersa3a3a032000-11-30 05:22:44 +0000849 character. In 1.6 and earlier, they never produced a sign,
850 and raised an error if the value of the long was too large
851 to fit in a Python int. In 2.0, they produced a sign if and
852 only if too large to fit in an int. This was inconsistent
853 across platforms (because the size of an int varies across
854 platforms), and inconsistent with hex() and oct(). Example:
855
856 >>> "%x" % -0x42L
Tim Peters9940b802000-12-01 07:59:35 +0000857 '-42' # in 2.1
Tim Petersa3a3a032000-11-30 05:22:44 +0000858 'ffffffbe' # in 2.0 and before, on 32-bit machines
859 >>> hex(-0x42L)
860 '-0x42L' # in all versions of Python
861
Tim Peters9940b802000-12-01 07:59:35 +0000862 The behavior of %d formats for negative Python longs remains
863 the same as in 2.0 (although in 1.6 and before, they raised
864 an error if the long didn't fit in a Python int).
865
866 %u formats don't make sense for Python longs, but are allowed
867 and treated the same as %d in 2.1. In 2.0, a negative long
868 formatted via %u produced a sign if and only if too large to
869 fit in an int. In 1.6 and earlier, a negative long formatted
870 via %u raised an error if it was too big to fit in an int.
871
Guido van Rossum3661d392000-12-12 22:10:31 +0000872- Dictionary objects have an odd new method, popitem(). This removes
873 an arbitrary item from the dictionary and returns it (in the form of
874 a (key, value) pair). This can be useful for algorithms that use a
875 dictionary as a bag of "to do" items and repeatedly need to pick one
876 item. Such algorithms normally end up running in quadratic time;
877 using popitem() they can usually be made to run in linear time.
878
Tim Peters36cdad12000-12-29 02:06:45 +0000879Standard library
880
Thomas Woutersfe385252001-01-19 23:16:56 +0000881- In the time module, the time argument to the functions strftime,
882 localtime, gmtime, asctime and ctime is now optional, defaulting to
883 the current time (in the local timezone).
884
Guido van Rossumda91f222001-01-15 16:36:08 +0000885- The ftplib module now defaults to passive mode, which is deemed a
886 more useful default given that clients are often inside firewalls
887 these days. Note that this could break if ftplib is used to connect
888 to a *server* that is inside a firewall, from outside; this is
889 expected to be a very rare situation. To fix that, you can call
890 ftp.set_pasv(0).
891
Martin v. Löwis10a27872001-01-13 09:54:41 +0000892- The module site now treats .pth files not only for path configuration,
893 but also supports extensions to the initialization code: Lines starting
894 with import are executed.
895
Guido van Rossumf61f1662001-01-10 20:13:55 +0000896- There's a new module, warnings, which implements a mechanism for
897 issuing and filtering warnings. There are some new built-in
898 exceptions that serve as warning categories, and a new command line
899 option, -W, to control warnings (e.g. -Wi ignores all warnings, -We
900 turns warnings into errors). warnings.warn(message[, category])
901 issues a warning message; this can also be called from C as
902 PyErr_Warn(category, message).
903
904- A new module xreadlines was added. This exports a single factory
905 function, xreadlines(). The intention is that this code is the
906 absolutely fastest way to iterate over all lines in an open
907 file(-like) object:
908
909 import xreadlines
910 for line in xreadlines.xreadlines(file):
911 ...do something to line...
912
913 This is equivalent to the previous the speed record holder using
914 file.readlines(sizehint). Note that if file is a real file object
915 (as opposed to a file-like object), this is equivalent:
916
917 for line in file.xreadlines():
918 ...do something to line...
919
Tim Peters36cdad12000-12-29 02:06:45 +0000920- The bisect module has new functions bisect_left, insort_left,
921 bisect_right and insort_right. The old names bisect and insort
922 are now aliases for bisect_right and insort_right. XXX_right
923 and XXX_left methods differ in what happens when the new element
924 compares equal to one or more elements already in the list: the
925 XXX_left methods insert to the left, the XXX_right methods to the
Tim Peters742bb6f2001-01-05 08:05:32 +0000926 right. Code that doesn't care where equal elements end up should
927 continue to use the old, short names ("bisect" and "insort").
Tim Peters36cdad12000-12-29 02:06:45 +0000928
Andrew M. Kuchlingf6f3a892001-01-13 14:53:34 +0000929- The new curses.panel module wraps the panel library that forms part
930 of SYSV curses and ncurses. Contributed by Thomas Gellekum.
931
Guido van Rossumf61f1662001-01-10 20:13:55 +0000932- The SocketServer module now sets the allow_reuse_address flag by
933 default in the TCPServer class.
934
935- A new function, sys._getframe(), returns the stack frame pointer of
936 the caller. This is intended only as a building block for
937 higher-level mechanisms such as string interpolation.
938
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000939- The pyexpat module supports a number of new handlers, which are
940 available only in expat 1.2. If invocation of a callback fails, it
941 will report an additional frame in the traceback. Parser objects
942 participate now in garbage collection. If expat reports an unknown
943 encoding, pyexpat will try to use a Python codec; that works only
944 for single-byte charsets. The parser type objects is exposed as
945 XMLParserObject.
946
947- xml.dom now offers standard definitions for symbolic node type and
948 exception code constants, and a hierarchy of DOM exceptions. minidom
949 was adjusted to use them.
950
951- The conformance of xml.dom.minidom to the DOM specification was
952 improved. It detects a number of additional error cases; the
953 previous/next relationship works even when the tree is modified;
954 Node supports the normalize() method; NamedNodeMap, DocumentType and
955 DOMImplementation classes were added; Element supports the
956 hasAttribute and hasAttributeNS methods; and Text supports the splitText
957 method.
958
Guido van Rossumf61f1662001-01-10 20:13:55 +0000959Build issues
960
Guido van Rossum1e33bdc2001-01-23 03:17:00 +0000961- For Unix (and Unix-compatible) builds, configuration and building of
962 extension modules is now greatly automated. Rather than having to
963 edit the Modules/Setup file to indicate which modules should be
964 built and where their include files and libraries are, a
965 distutils-based setup.py script now takes care of building most
966 extension modules. All extension modules built this way are built
967 as shared libraries. Only a few modules that must be linked
968 statically are still listed in the Setup file; you won't need to
969 edit their configuration.
970
971- Python should now build out of the box on Cygwin. If it doesn't,
972 mail to Jason Tishler (jlt63 at users.sourceforge.net).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000973
974- Python now always uses its own (renamed) implementation of getopt()
975 -- there's too much variation among C library getopt()
976 implementations.
977
978- C++ compilers are better supported; the CXX macro is always set to a
979 C++ compiler if one is found.
Tim Peters36cdad12000-12-29 02:06:45 +0000980
Tim Petersd92dfe02000-12-12 01:18:41 +0000981Windows changes
982
983- select module: By default under Windows, a select() call
984 can specify no more than 64 sockets. Python now boosts
985 this Microsoft default to 512. If you need even more than
986 that, see the MS docs (you'll need to #define FD_SETSIZE
987 and recompile Python from source).
988
Guido van Rossumf61f1662001-01-10 20:13:55 +0000989- Support for Windows 3.1, DOS and OS/2 is gone. The Lib/dos-8x3
990 subdirectory is no more!
991
Tim Petersa3a3a032000-11-30 05:22:44 +0000992
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000993What's New in Python 2.0?
Fred Drake1a640502000-10-16 20:27:25 +0000994=========================
Guido van Rossum61000331997-08-15 04:39:58 +0000995
Guido van Rossum8ed602b2000-09-01 22:34:33 +0000996Below is a list of all relevant changes since release 1.6. Older
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000997changes are in the file HISTORY. If you are making the jump directly
998from Python 1.5.2 to 2.0, make sure to read the section for 1.6 in the
999HISTORY file! Many important changes listed there.
Guido van Rossum61000331997-08-15 04:39:58 +00001000
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001001Alternatively, a good overview of the changes between 1.5.2 and 2.0 is
1002the document "What's New in Python 2.0" by Kuchling and Moshe Zadka:
1003http://starship.python.net/crew/amk/python/writing/new-python/.
Guido van Rossum1f83cce1997-10-06 21:04:35 +00001004
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001005--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)
Guido van Rossum437cfe81999-04-08 20:17:57 +00001006
1007======================================================================
1008
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001009What's new in 2.0 (since release candidate 1)?
1010==============================================
1011
1012Standard library
1013
1014- The copy_reg module was modified to clarify its intended use: to
1015 register pickle support for extension types, not for classes.
1016 pickle() will raise a TypeError if it is passed a class.
1017
1018- Fixed a bug in gettext's "normalize and expand" code that prevented
1019 it from finding an existing .mo file.
1020
1021- Restored support for HTTP/0.9 servers in httplib.
1022
Tim Peters989b7b92000-10-16 20:24:53 +00001023- The math module was changed to stop raising OverflowError in case of
1024 underflow, and return 0 instead in underflow cases. Whether Python
1025 used to raise OverflowError in case of underflow was platform-
1026 dependent (it did when the platform math library set errno to ERANGE
1027 on underflow).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001028
1029- Fixed a bug in StringIO that occurred when the file position was not
1030 at the end of the file and write() was called with enough data to
1031 extend past the end of the file.
1032
1033- Fixed a bug that caused Tkinter error messages to get lost on
1034 Windows. The bug was fixed by replacing direct use of
1035 interp->result with Tcl_GetStringResult(interp).
1036
1037- Fixed bug in urllib2 that caused it to fail when it received an HTTP
1038 redirect response.
1039
1040- Several changes were made to distutils: Some debugging code was
1041 removed from util. Fixed the installer used when an external zip
1042 program (like WinZip) is not found; the source code for this
1043 installer is in Misc/distutils. check_lib() was modified to behave
1044 more like AC_CHECK_LIB by add other_libraries() as a parameter. The
1045 test for whether installed modules are on sys.path was changed to
1046 use both normcase() and normpath().
1047
Jeremy Hyltond867a2c2000-10-16 20:41:38 +00001048- Several minor bugs were fixed in the xml package (the minidom,
1049 pulldom, expatreader, and saxutils modules).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001050
1051- The regression test driver (regrtest.py) behavior when invoked with
1052 -l changed: It now reports a count of objects that are recognized as
1053 garbage but not freed by the garbage collector.
1054
Tim Peters989b7b92000-10-16 20:24:53 +00001055- The regression test for the math module was changed to test
1056 exceptional behavior when the test is run in verbose mode. Python
1057 cannot yet guarantee consistent exception behavior across platforms,
1058 so the exception part of test_math is run only in verbose mode, and
1059 may fail on your platform.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001060
1061Internals
1062
1063- PyOS_CheckStack() has been disabled on Win64, where it caused
1064 test_sre to fail.
1065
1066Build issues
1067
1068- Changed compiler flags, so that gcc is always invoked with -Wall and
1069 -Wstrict-prototypes. Users compiling Python with GCC should see
1070 exactly one warning, except if they have passed configure the
Tim Peters989b7b92000-10-16 20:24:53 +00001071 --with-pydebug flag. The expected warning is for getopt() in
Tim Petersadfb94f2000-10-16 20:51:33 +00001072 Modules/main.c. This warning will be fixed for Python 2.1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001073
Tim Petersa3a3a032000-11-30 05:22:44 +00001074- Fixed configure to add -threads argument during linking on OSF1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001075
1076Tools and other miscellany
1077
1078- The compiler in Tools/compiler was updated to support the new
1079 language features introduced in 2.0: extended print statement, list
1080 comprehensions, and augmented assignments. The new compiler should
1081 also be backwards compatible with Python 1.5.2; the compiler will
1082 always generate code for the version of the interpreter it runs
Tim Petersa3a3a032000-11-30 05:22:44 +00001083 under.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001084
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001085What's new in 2.0 release candidate 1 (since beta 2)?
1086=====================================================
1087
Jeremy Hylton6040aaa2000-10-09 21:27:22 +00001088What is release candidate 1?
1089
1090We believe that release candidate 1 will fix all known bugs that we
1091intend to fix for the 2.0 final release. This release should be a bit
1092more stable than the previous betas. We would like to see even more
1093widespread testing before the final release, so we are producing this
1094release candidate. The final release will be exactly the same unless
1095any show-stopping (or brown bag) bugs are found by testers of the
1096release candidate.
1097
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001098All the changes since the last beta release are bug fixes or changes
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001099to support building Python for specific platforms.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001100
1101Core language, builtins, and interpreter
1102
1103- A bug that caused crashes when __coerce__ was used with augmented
1104 assignment, e.g. +=, was fixed.
1105
1106- Raise ZeroDivisionError when raising zero to a negative number,
1107 e.g. 0.0 ** -2.0. Note that math.pow is unrelated to the builtin
1108 power operator and the result of math.pow(0.0, -2.0) will vary by
1109 platform. On Linux, it raises a ValueError.
1110
1111- A bug in Unicode string interpolation was fixed that occasionally
1112 caused errors with formats including "%%". For example, the
1113 following expression "%% %s" % u"abc" no longer raises a TypeError.
1114
1115- Compilation of deeply nested expressions raises MemoryError instead
1116 of SyntaxError, e.g. eval("[" * 50 + "]" * 50).
1117
1118- In 2.0b2 on Windows, the interpreter wrote .pyc files in text mode,
1119 rendering them useless. They are now written in binary mode again.
1120
1121Standard library
1122
1123- Keyword arguments are now accepted for most pattern and match object
1124 methods in SRE, the standard regular expression engine.
1125
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001126- In SRE, fixed error with negative lookahead and lookbehind that
Jeremy Hylton32e20ff2000-10-09 19:48:11 +00001127 manifested itself as a runtime error in patterns like "(?<!abc)(def)".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001128
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001129- Several bugs in the Unicode handling and error handling in _tkinter
1130 were fixed.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001131
1132- Fix memory management errors in Merge() and Tkapp_Call() routines.
1133
1134- Several changes were made to cStringIO to make it compatible with
1135 the file-like object interface and with StringIO. If operations are
1136 performed on a closed object, an exception is raised. The truncate
1137 method now accepts a position argument and readline accepts a size
Tim Petersa3a3a032000-11-30 05:22:44 +00001138 argument.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001139
1140- There were many changes made to the linuxaudiodev module and its
1141 test suite; as a result, a short, unexpected audio sample should now
Tim Petersa3a3a032000-11-30 05:22:44 +00001142 play when the regression test is run.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001143
1144 Note that this module is named poorly, because it should work
1145 correctly on any platform that supports the Open Sound System
Tim Petersa3a3a032000-11-30 05:22:44 +00001146 (OSS).
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001147
1148 The module now raises exceptions when errors occur instead of
1149 crashing. It also defines the AFMT_A_LAW format (logarithmic A-law
1150 audio) and defines a getptr() method that calls the
1151 SNDCTL_DSP_GETxPTR ioctl defined in the OSS Programmer's Guide.
1152
1153- The library_version attribute, introduced in an earlier beta, was
1154 removed because it can not be supported with early versions of the C
1155 readline library, which provides no way to determine the version at
1156 compile-time.
1157
1158- The binascii module is now enabled on Win64.
1159
Tim Peters46446d62000-10-09 21:19:31 +00001160- tokenize.py no longer suffers "recursion depth" errors when parsing
1161 programs with very long string literals.
1162
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001163Internals
1164
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001165- Fixed several buffer overflow vulnerabilities in calculate_path(),
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001166 which is called when the interpreter starts up to determine where
1167 the standard library is installed. These vulnerabilities affect all
1168 previous versions of Python and can be exploited by setting very
1169 long values for PYTHONHOME or argv[0]. The risk is greatest for a
1170 setuid Python script, although use of the wrapper in
1171 Misc/setuid-prog.c will eliminate the vulnerability.
1172
1173- Fixed garbage collection bugs in instance creation that were
1174 triggered when errors occurred during initialization. The solution,
1175 applied in cPickle and in PyInstance_New(), is to call
1176 PyObject_GC_Init() after the initialization of the object's
1177 container attributes is complete.
1178
1179- pyexpat adds definitions of PyModule_AddStringConstant and
1180 PyModule_AddObject if the Python version is less than 2.0, which
1181 provides compatibility with PyXML on Python 1.5.2.
1182
1183- If the platform has a bogus definition for LONG_BIT (the number of
1184 bits in a long), an error will be reported at compile time.
1185
1186- Fix bugs in _PyTuple_Resize() which caused hard-to-interpret garbage
1187 collection crashes and possibly other, unreported crashes.
1188
1189- Fixed a memory leak in _PyUnicode_Fini().
1190
1191Build issues
1192
1193- configure now accepts a --with-suffix option that specifies the
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001194 executable suffix. This is useful for builds on Cygwin and Mac OS
Tim Petersa3a3a032000-11-30 05:22:44 +00001195 X, for example.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001196
1197- The mmap.PAGESIZE constant is now initialized using sysconf when
1198 possible, which eliminates a dependency on -lucb for Reliant UNIX.
1199
1200- The md5 file should now compile on all platforms.
1201
1202- The select module now compiles on platforms that do not define
1203 POLLRDNORM and related constants.
1204
1205- Darwin (Mac OS X): Initial support for static builds on this
Tim Petersa3a3a032000-11-30 05:22:44 +00001206 platform.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001207
Jeremy Hylton10921202000-10-09 18:34:12 +00001208- BeOS: A number of changes were made to the build and installation
1209 process. ar-fake now operates on a directory of object files.
1210 dl_export.h is gone, and its macros now appear on the mwcc command
1211 line during build on PPC BeOS.
1212
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001213- Platform directory in lib/python2.0 is "plat-beos5" (or
Jeremy Hylton10921202000-10-09 18:34:12 +00001214 "plat-beos4", if building on BeOS 4.5), rather than "plat-beos".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00001215
1216- Cygwin: Support for shared libraries, Tkinter, and sockets.
1217
1218- SunOS 4.1.4_JL: Fix test for directory existence in configure.
1219
1220Tools and other miscellany
1221
1222- Removed debugging prints from main used with freeze.
1223
Tim Peters46446d62000-10-09 21:19:31 +00001224- IDLE auto-indent no longer crashes when it encounters Unicode
1225 characters.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001226
1227What's new in 2.0 beta 2 (since beta 1)?
1228========================================
1229
1230Core language, builtins, and interpreter
1231
Tim Peters482c0212000-09-26 06:33:09 +00001232- Add support for unbounded ints in %d,i,u,x,X,o formats; for example
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001233 "%d" % 2L**64 == "18446744073709551616".
Jeremy Hylton1b618592000-09-26 05:32:36 +00001234
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001235- Add -h and -V command line options to print the usage message and
1236 Python version number and exit immediately.
1237
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001238- eval() and exec accept Unicode objects as code parameters.
1239
1240- getattr() and setattr() now also accept Unicode objects for the
1241 attribute name, which are converted to strings using the default
1242 encoding before lookup.
1243
1244- Multiplication on string and Unicode now does proper bounds
1245 checking; e.g. 'a' * 65536 * 65536 will raise ValueError, "repeated
1246 string is too long."
1247
1248- Better error message when continue is found in try statement in a
Tim Petersa3a3a032000-11-30 05:22:44 +00001249 loop.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001250
Jeremy Hylton1b618592000-09-26 05:32:36 +00001251
1252Standard library and extensions
1253
Guido van Rossum5b08f132001-04-16 02:05:23 +00001254- socket module: the OpenSSL code now adds support for RAND_status()
1255 and EGD (Entropy Gathering Device).
1256
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001257- array: reverse() method of array now works. buffer_info() now does
Jeremy Hylton1b618592000-09-26 05:32:36 +00001258 argument checking; it still takes no arguments.
1259
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001260- asyncore/asynchat: Included most recent version from Sam Rushing.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001261
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001262- cgi: Accept '&' or ';' as separator characters when parsing form data.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001263
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001264- CGIHTTPServer: Now works on Windows (and perhaps even Mac).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001265
1266- ConfigParser: When reading the file, options spelled in upper case
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001267 letters are now correctly converted to lowercase.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001268
1269- copy: Copy Unicode objects atomically.
1270
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001271- cPickle: Fail gracefully when copy_reg can't be imported.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001272
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001273- cStringIO: Implemented readlines() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001274
Fred Drake67233bc2000-09-26 16:40:27 +00001275- dbm: Add get() and setdefault() methods to dbm object. Add constant
1276 `library' to module that names the library used. Added doc strings
1277 and method names to error messages. Uses configure to determine
1278 which ndbm.h file to include; Berkeley DB's nbdm and GDBM's ndbm is
1279 now available options.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001280
1281- distutils: Update to version 0.9.3.
1282
1283- dl: Add several dl.RTLD_ constants.
1284
1285- fpectl: Now supported on FreeBSD.
1286
1287- gc: Add DEBUG_SAVEALL option. When enabled all garbage objects
1288 found by the collector will be saved in gc.garbage. This is useful
1289 for debugging a program that creates reference cycles.
1290
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001291- httplib: Three changes: Restore support for set_debuglevel feature
Jeremy Hylton1b618592000-09-26 05:32:36 +00001292 of HTTP class. Do not close socket on zero-length response. Do not
1293 crash when server sends invalid content-length header.
1294
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001295- mailbox: Mailbox class conforms better to qmail specifications.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001296
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001297- marshal: When reading a short, sign-extend on platforms where shorts
1298 are bigger than 16 bits. When reading a long, repair the unportable
1299 sign extension that was being done for 64-bit machines. (It assumed
1300 that signed right shift sign-extends.)
1301
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001302- operator: Add contains(), invert(), __invert__() as aliases for
1303 __contains__(), inv(), and __inv__() respectively.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001304
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001305- os: Add support for popen2() and popen3() on all platforms where
1306 fork() exists. (popen4() is still in the works.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00001307
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001308- os: (Windows only:) Add startfile() function that acts like double-
Tim Peters482c0212000-09-26 06:33:09 +00001309 clicking on a file in Explorer (or passing the file name to the
1310 DOS "start" command).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001311
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001312- os.path: (Windows, DOS:) Treat trailing colon correctly in
Tim Peters482c0212000-09-26 06:33:09 +00001313 os.path.join. os.path.join("a:", "b") yields "a:b".
Jeremy Hylton1b618592000-09-26 05:32:36 +00001314
1315- pickle: Now raises ValueError when an invalid pickle that contains
1316 a non-string repr where a string repr was expected. This behavior
1317 matches cPickle.
1318
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001319- posixfile: Remove broken __del__() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001320
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001321- py_compile: support CR+LF line terminators in source file.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001322
1323- readline: Does not immediately exit when ^C is hit when readline and
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001324 threads are configured. Adds definition of rl_library_version. (The
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001325 latter addition requires GNU readline 2.2 or later.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00001326
1327- rfc822: Domain literals returned by AddrlistClass method
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001328 getdomainliteral() are now properly wrapped in brackets.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001329
1330- site: sys.setdefaultencoding() should only be called in case the
Tim Peters482c0212000-09-26 06:33:09 +00001331 standard default encoding ("ascii") is changed. This saves quite a
Jeremy Hylton1b618592000-09-26 05:32:36 +00001332 few cycles during startup since the first call to
1333 setdefaultencoding() will initialize the codec registry and the
1334 encodings package.
1335
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001336- socket: Support for size hint in readlines() method of object returned
1337 by makefile().
Jeremy Hylton1b618592000-09-26 05:32:36 +00001338
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001339- sre: Added experimental expand() method to match objects. Does not
Jeremy Hylton625915e2000-10-02 13:43:33 +00001340 use buffer interface on Unicode strings. Does not hang if group id
Jeremy Hylton1b618592000-09-26 05:32:36 +00001341 is followed by whitespace.
1342
Tim Petersa3a3a032000-11-30 05:22:44 +00001343- StringIO: Size hint in readlines() is now supported as documented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001344
1345- struct: Check ranges for bytes and shorts.
1346
1347- urllib: Improved handling of win32 proxy settings. Fixed quote and
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001348 quote_plus functions so that the always encode a comma.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001349
1350- Tkinter: Image objects are now guaranteed to have unique ids. Set
1351 event.delta to zero if Tk version doesn't support mousewheel.
1352 Removed some debugging prints.
1353
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001354- UserList: now implements __contains__().
Jeremy Hylton1b618592000-09-26 05:32:36 +00001355
Fred Drake67233bc2000-09-26 16:40:27 +00001356- webbrowser: On Windows, use os.startfile() instead of os.popen(),
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001357 which works around a bug in Norton AntiVirus 2000 that leads directly
1358 to a Blue Screen freeze.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001359
1360- xml: New version detection code allows PyXML to override standard
1361 XML package if PyXML version is greater than 0.6.1.
1362
Fred Drake64bb3802000-09-26 16:21:35 +00001363- xml.dom: DOM level 1 support for basic XML. Includes xml.dom.minidom
1364 (conventional DOM), and xml.dom.pulldom, which allows building the DOM
1365 tree only for nodes which are sufficiently interesting to a specific
1366 application. Does not provide the HTML-specific extensions. Still
1367 undocumented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001368
Fred Drake64bb3802000-09-26 16:21:35 +00001369- xml.sax: SAX 2 support for Python, including all the handler
1370 interfaces needed to process XML 1.0 compliant XML. Some
1371 documentation is already available.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001372
Fred Drake64bb3802000-09-26 16:21:35 +00001373- pyexpat: Renamed to xml.parsers.expat since this is part of the new,
1374 packagized XML support.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001375
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001376
Jeremy Hylton1b618592000-09-26 05:32:36 +00001377C API
1378
1379- Add three new convenience functions for module initialization --
1380 PyModule_AddObject(), PyModule_AddIntConstant(), and
1381 PyModule_AddStringConstant().
1382
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001383- Cleaned up definition of NULL in C source code; all definitions were
Jeremy Hylton1b618592000-09-26 05:32:36 +00001384 removed and add #error to Python.h if NULL isn't defined after
1385 #include of stdio.h.
1386
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001387- Py_PROTO() macros that were removed in 2.0b1 have been restored for
Jeremy Hylton1b618592000-09-26 05:32:36 +00001388 backwards compatibility (at the source level) with old extensions.
1389
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001390- A wrapper API was added for signal() and sigaction(). Instead of
1391 either function, always use PyOS_getsig() to get a signal handler
1392 and PyOS_setsig() to set one. A new convenience typedef
1393 PyOS_sighandler_t is defined for the type of signal handlers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001394
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001395- Add PyString_AsStringAndSize() function that provides access to the
Jeremy Hylton1b618592000-09-26 05:32:36 +00001396 internal data buffer and size of a string object -- or the default
1397 encoded version of a Unicode object.
1398
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001399- PyString_Size() and PyString_AsString() accept Unicode objects.
1400
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001401- The standard header <limits.h> is now included by Python.h (if it
Fred Drake64bb3802000-09-26 16:21:35 +00001402 exists). INT_MAX and LONG_MAX will always be defined, even if
1403 <limits.h> is not available.
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001404
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001405- PyFloat_FromString takes a second argument, pend, that was
1406 effectively useless. It is now officially useless but preserved for
1407 backwards compatibility. If the pend argument is not NULL, *pend is
1408 set to NULL.
1409
1410- PyObject_GetAttr() and PyObject_SetAttr() now accept Unicode objects
1411 for the attribute name. See note on getattr() above.
1412
1413- A few bug fixes to argument processing for Unicode.
1414 PyArg_ParseTupleAndKeywords() now accepts "es#" and "es".
1415 PyArg_Parse() special cases "s#" for Unicode objects; it returns a
1416 pointer to the default encoded string data instead of to the raw
Tim Petersa3a3a032000-11-30 05:22:44 +00001417 UTF-16.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001418
1419- Py_BuildValue accepts B format (for bgen-generated code).
1420
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001421
Jeremy Hylton1b618592000-09-26 05:32:36 +00001422Internals
1423
1424- On Unix, fix code for finding Python installation directory so that
1425 it works when argv[0] is a relative path.
1426
Andrew M. Kuchlinga1099be2000-12-15 01:16:43 +00001427- Added a true unicode_internal_encode() function and fixed the
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001428 unicode_internal_decode function() to support Unicode objects directly
Jeremy Hylton1b618592000-09-26 05:32:36 +00001429 rather than by generating a copy of the object.
1430
Tim Peters482c0212000-09-26 06:33:09 +00001431- Several of the internal Unicode tables are much smaller now, and
1432 the source code should be much friendlier to weaker compilers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001433
Jeremy Hylton97693b02000-09-26 17:42:51 +00001434- In the garbage collector: Fixed bug in collection of tuples. Fixed
1435 bug that caused some instances to be removed from the container set
1436 while they were still live. Fixed parsing in gc.set_debug() for
1437 platforms where sizeof(long) > sizeof(int).
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001438
1439- Fixed refcount problem in instance deallocation that only occurred
1440 when Py_REF_DEBUG was defined and Py_TRACE_REFS was not.
1441
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001442- On Windows, getpythonregpath is now protected against null data in
1443 registry key.
1444
1445- On Unix, create .pyc/.pyo files with O_EXCL flag to avoid a race
Tim Petersa3a3a032000-11-30 05:22:44 +00001446 condition.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001447
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001448
Jeremy Hylton1b618592000-09-26 05:32:36 +00001449Build and platform-specific issues
1450
1451- Better support of GNU Pth via --with-pth configure option.
1452
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001453- Python/C API now properly exposed to dynamically-loaded extension
1454 modules on Reliant UNIX.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001455
1456- Changes for the benefit of SunOS 4.1.4 (really!). mmapmodule.c:
1457 Don't define MS_SYNC to be zero when it is undefined. Added missing
1458 prototypes in posixmodule.c.
1459
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001460- Improved support for HP-UX build. Threads should now be correctly
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001461 configured (on HP-UX 10.20 and 11.00).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001462
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001463- Fix largefile support on older NetBSD systems and OpenBSD by adding
1464 define for TELL64.
1465
1466
1467Tools and other miscellany
1468
1469- ftpmirror: Call to main() is wrapped in if __name__ == "__main__".
1470
1471- freeze: The modulefinder now works with 2.0 opcodes.
1472
Tim Petersa3a3a032000-11-30 05:22:44 +00001473- IDLE:
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001474 Move hackery of sys.argv until after the Tk instance has been
1475 created, which allows the application-specific Tkinter
1476 initialization to be executed if present; also pass an explicit
1477 className parameter to the Tk() constructor.
Fred Drake64bb3802000-09-26 16:21:35 +00001478
Jeremy Hylton1b618592000-09-26 05:32:36 +00001479
1480What's new in 2.0 beta 1?
1481=========================
1482
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001483Source Incompatibilities
1484------------------------
1485
1486None. Note that 1.6 introduced several incompatibilities with 1.5.2,
1487such as single-argument append(), connect() and bind(), and changes to
1488str(long) and repr(float).
1489
1490
1491Binary Incompatibilities
1492------------------------
1493
1494- Third party extensions built for Python 1.5.x or 1.6 cannot be used
1495with Python 2.0; these extensions will have to be rebuilt for Python
14962.0.
1497
1498- On Windows, attempting to import a third party extension built for
1499Python 1.5.x or 1.6 results in an immediate crash; there's not much we
1500can do about this. Check your PYTHONPATH environment variable!
1501
1502- Python bytecode files (*.pyc and *.pyo) are not compatible between
1503releases.
1504
1505
1506Overview of Changes Since 1.6
1507-----------------------------
1508
1509There are many new modules (including brand new XML support through
1510the xml package, and i18n support through the gettext module); a list
1511of all new modules is included below. Lots of bugs have been fixed.
1512
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001513The process for making major new changes to the language has changed
1514since Python 1.6. Enhancements must now be documented by a Python
1515Enhancement Proposal (PEP) before they can be accepted.
1516
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001517There are several important syntax enhancements, described in more
1518detail below:
1519
1520 - Augmented assignment, e.g. x += 1
1521
1522 - List comprehensions, e.g. [x**2 for x in range(10)]
1523
1524 - Extended import statement, e.g. import Module as Name
1525
1526 - Extended print statement, e.g. print >> file, "Hello"
1527
1528Other important changes:
1529
1530 - Optional collection of cyclical garbage
1531
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001532Python Enhancement Proposal (PEP)
1533---------------------------------
1534
1535PEP stands for Python Enhancement Proposal. A PEP is a design
1536document providing information to the Python community, or describing
1537a new feature for Python. The PEP should provide a concise technical
1538specification of the feature and a rationale for the feature.
1539
1540We intend PEPs to be the primary mechanisms for proposing new
1541features, for collecting community input on an issue, and for
1542documenting the design decisions that have gone into Python. The PEP
1543author is responsible for building consensus within the community and
1544documenting dissenting opinions.
1545
1546The PEPs are available at http://python.sourceforge.net/peps/.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001547
1548Augmented Assignment
1549--------------------
1550
1551This must have been the most-requested feature of the past years!
1552Eleven new assignment operators were added:
1553
Guido van Rossume905e952000-09-05 12:42:46 +00001554 += -= *= /= %= **= <<= >>= &= ^= |=
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001555
1556For example,
1557
1558 A += B
1559
1560is similar to
1561
1562 A = A + B
1563
1564except that A is evaluated only once (relevant when A is something
1565like dict[index].attr).
1566
1567However, if A is a mutable object, A may be modified in place. Thus,
1568if A is a number or a string, A += B has the same effect as A = A+B
1569(except A is only evaluated once); but if a is a list, A += B has the
1570same effect as A.extend(B)!
1571
1572Classes and built-in object types can override the new operators in
1573order to implement the in-place behavior; the not-in-place behavior is
1574used automatically as a fallback when an object doesn't implement the
1575in-place behavior. For classes, the method name is derived from the
1576method name for the corresponding not-in-place operator by inserting
1577an 'i' in front of the name, e.g. __iadd__ implements in-place
1578__add__.
1579
1580Augmented assignment was implemented by Thomas Wouters.
1581
1582
1583List Comprehensions
1584-------------------
1585
1586This is a flexible new notation for lists whose elements are computed
1587from another list (or lists). The simplest form is:
1588
1589 [<expression> for <variable> in <sequence>]
1590
Guido van Rossum56db0952000-09-06 23:34:25 +00001591For example, [i**2 for i in range(4)] yields the list [0, 1, 4, 9].
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001592This is more efficient than a for loop with a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001593
1594You can also add a condition:
1595
1596 [<expression> for <variable> in <sequence> if <condition>]
1597
1598For example, [w for w in words if w == w.lower()] would yield the list
1599of words that contain no uppercase characters. This is more efficient
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001600than a for loop with an if statement and a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001601
1602You can also have nested for loops and more than one 'if' clause. For
1603example, here's a function that flattens a sequence of sequences::
1604
1605 def flatten(seq):
1606 return [x for subseq in seq for x in subseq]
1607
1608 flatten([[0], [1,2,3], [4,5], [6,7,8,9], []])
1609
1610This prints
1611
1612 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
1613
1614List comprehensions originated as a patch set from Greg Ewing; Skip
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001615Montanaro and Thomas Wouters also contributed. Described by PEP 202.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001616
1617
1618Extended Import Statement
1619-------------------------
1620
1621Many people have asked for a way to import a module under a different
1622name. This can be accomplished like this:
1623
1624 import foo
1625 bar = foo
1626 del foo
1627
1628but this common idiom gets old quickly. A simple extension of the
1629import statement now allows this to be written as follows:
1630
1631 import foo as bar
1632
1633There's also a variant for 'from ... import':
1634
1635 from foo import bar as spam
1636
1637This also works with packages; e.g. you can write this:
1638
1639 import test.regrtest as regrtest
1640
1641Note that 'as' is not a new keyword -- it is recognized only in this
1642context (this is only possible because the syntax for the import
1643statement doesn't involve expressions).
1644
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001645Implemented by Thomas Wouters. Described by PEP 221.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001646
1647
1648Extended Print Statement
1649------------------------
1650
1651Easily the most controversial new feature, this extension to the print
1652statement adds an option to make the output go to a different file
1653than the default sys.stdout.
1654
1655For example, to write an error message to sys.stderr, you can now
1656write:
1657
1658 print >> sys.stderr, "Error: bad dog!"
1659
1660As a special feature, if the expression used to indicate the file
Fred Drake45888ff2000-09-29 17:09:11 +00001661evaluates to None, the current value of sys.stdout is used. Thus:
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001662
1663 print >> None, "Hello world"
1664
1665is equivalent to
1666
1667 print "Hello world"
1668
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001669Design and implementation by Barry Warsaw. Described by PEP 214.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001670
1671
1672Optional Collection of Cyclical Garbage
1673---------------------------------------
1674
1675Python is now equipped with a garbage collector that can hunt down
1676cyclical references between Python objects. It's no replacement for
1677reference counting; in fact, it depends on the reference counts being
1678correct, and decides that a set of objects belong to a cycle if all
1679their reference counts can be accounted for from their references to
1680each other. This devious scheme was first proposed by Eric Tiedemann,
1681and brought to implementation by Neil Schemenauer.
1682
1683There's a module "gc" that lets you control some parameters of the
1684garbage collection. There's also an option to the configure script
1685that lets you enable or disable the garbage collection. In 2.0b1,
1686it's on by default, so that we (hopefully) can collect decent user
1687experience with this new feature. There are some questions about its
Fred Drake9f11cf82000-09-29 17:54:40 +00001688performance. If it proves to be too much of a problem, we'll turn it
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001689off by default in the final 2.0 release.
1690
1691
1692Smaller Changes
1693---------------
1694
1695A new function zip() was added. zip(seq1, seq2, ...) is equivalent to
1696map(None, seq1, seq2, ...) when the sequences have the same length;
1697i.e. zip([1,2,3], [10,20,30]) returns [(1,10), (2,20), (3,30)]. When
1698the lists are not all the same length, the shortest list wins:
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001699zip([1,2,3], [10,20]) returns [(1,10), (2,20)]. See PEP 201.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001700
1701sys.version_info is a tuple (major, minor, micro, level, serial).
1702
1703Dictionaries have an odd new method, setdefault(key, default).
1704dict.setdefault(key, default) returns dict[key] if it exists; if not,
1705it sets dict[key] to default and returns that value. Thus:
1706
1707 dict.setdefault(key, []).append(item)
1708
1709does the same work as this common idiom:
1710
1711 if not dict.has_key(key):
1712 dict[key] = []
1713 dict[key].append(item)
1714
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001715There are two new variants of SyntaxError that are raised for
1716indentation-related errors: IndentationError and TabError.
1717
1718Changed \x to consume exactly two hex digits; see PEP 223. Added \U
1719escape that consumes exactly eight hex digits.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001720
1721The limits on the size of expressions and file in Python source code
1722have been raised from 2**16 to 2**32. Previous versions of Python
1723were limited because the maximum argument size the Python VM accepted
1724was 2**16. This limited the size of object constructor expressions,
1725e.g. [1,2,3] or {'a':1, 'b':2}, and the size of source files. This
1726limit was raised thanks to a patch by Charles Waldman that effectively
1727fixes the problem. It is now much more likely that you will be
1728limited by available memory than by an arbitrary limit in Python.
1729
1730The interpreter's maximum recursion depth can be modified by Python
1731programs using sys.getrecursionlimit and sys.setrecursionlimit. This
1732limit is the maximum number of recursive calls that can be made by
1733Python code. The limit exists to prevent infinite recursion from
1734overflowing the C stack and causing a core dump. The default value is
17351000. The maximum safe value for a particular platform can be found
1736by running Misc/find_recursionlimit.py.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001737
1738New Modules and Packages
1739------------------------
1740
1741atexit - for registering functions to be called when Python exits.
1742
1743imputil - Greg Stein's alternative API for writing custom import
1744hooks.
1745
1746pyexpat - an interface to the Expat XML parser, contributed by Paul
1747Prescod.
1748
1749xml - a new package with XML support code organized (so far) in three
1750subpackages: xml.dom, xml.sax, and xml.parsers. Describing these
1751would fill a volume. There's a special feature whereby a
1752user-installed package named _xmlplus overrides the standard
1753xmlpackage; this is intended to give the XML SIG a hook to distribute
1754backwards-compatible updates to the standard xml package.
1755
1756webbrowser - a platform-independent API to launch a web browser.
1757
1758
Guido van Rossume905e952000-09-05 12:42:46 +00001759Changed Modules
1760---------------
1761
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001762array -- new methods for array objects: count, extend, index, pop, and
1763remove
1764
1765binascii -- new functions b2a_hex and a2b_hex that convert between
1766binary data and its hex representation
1767
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001768calendar -- Many new functions that support features including control
1769over which day of the week is the first day, returning strings instead
1770of printing them. Also new symbolic constants for days of week,
1771e.g. MONDAY, ..., SUNDAY.
1772
1773cgi -- FieldStorage objects have a getvalue method that works like a
1774dictionary's get method and returns the value attribute of the object.
1775
1776ConfigParser -- The parser object has new methods has_option,
1777remove_section, remove_option, set, and write. They allow the module
1778to be used for writing config files as well as reading them.
1779
1780ftplib -- ntransfercmd(), transfercmd(), and retrbinary() all now
Guido van Rossume905e952000-09-05 12:42:46 +00001781optionally support the RFC 959 REST command.
1782
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001783gzip -- readline and readlines now accept optional size arguments
Guido van Rossume905e952000-09-05 12:42:46 +00001784
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001785httplib -- New interfaces and support for HTTP/1.1 by Greg Stein. See
1786the module doc strings for details.
Guido van Rossum830ca2a2000-09-05 15:34:16 +00001787
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001788locale -- implement getdefaultlocale for Win32 and Macintosh
1789
1790marshal -- no longer dumps core when marshaling deeply nested or
1791recursive data structures
1792
1793os -- new functions isatty, seteuid, setegid, setreuid, setregid
1794
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001795os/popen2 -- popen2/popen3/popen4 support under Windows. popen2/popen3
1796support under Unix.
1797
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001798os/pty -- support for openpty and forkpty
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001799
1800os.path -- fix semantics of os.path.commonprefix
1801
1802smtplib -- support for sending very long messages
1803
1804socket -- new function getfqdn()
1805
1806readline -- new functions to read, write and truncate history files.
1807The readline section of the library reference manual contains an
1808example.
1809
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001810select -- add interface to poll system call
1811
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001812shutil -- new copyfileobj function
1813
1814SimpleHTTPServer, CGIHTTPServer -- Fix problems with buffering in the
1815HTTP server.
1816
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001817Tkinter -- optimization of function flatten
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001818
1819urllib -- scans environment variables for proxy configuration,
Tim Peters8b092332000-09-05 20:15:25 +00001820e.g. http_proxy.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001821
1822whichdb -- recognizes dumbdbm format
Guido van Rossume905e952000-09-05 12:42:46 +00001823
1824
1825Obsolete Modules
1826----------------
1827
1828None. However note that 1.6 made a whole slew of modules obsolete:
1829stdwin, soundex, cml, cmpcache, dircache, dump, find, grep, packmail,
1830poly, zmod, strop, util, whatsound.
1831
1832
1833Changed, New, Obsolete Tools
1834----------------------------
1835
Tim Peters8b092332000-09-05 20:15:25 +00001836None.
Guido van Rossume905e952000-09-05 12:42:46 +00001837
1838
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001839C-level Changes
1840---------------
1841
1842Several cleanup jobs were carried out throughout the source code.
1843
1844All C code was converted to ANSI C; we got rid of all uses of the
1845Py_PROTO() macro, which makes the header files a lot more readable.
1846
1847Most of the portability hacks were moved to a new header file,
1848pyport.h; several other new header files were added and some old
1849header files were removed, in an attempt to create a more rational set
1850of header files. (Few of these ever need to be included explicitly;
1851they are all included by Python.h.)
1852
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001853Trent Mick ensured portability to 64-bit platforms, under both Linux
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001854and Win64, especially for the new Intel Itanium processor. Mick also
1855added large file support for Linux64 and Win64.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001856
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001857The C APIs to return an object's size have been update to consistently
1858use the form PyXXX_Size, e.g. PySequence_Size and PyDict_Size. In
1859previous versions, the abstract interfaces used PyXXX_Length and the
1860concrete interfaces used PyXXX_Size. The old names,
1861e.g. PyObject_Length, are still available for backwards compatibility
1862at the API level, but are deprecated.
1863
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001864The PyOS_CheckStack function has been implemented on Windows by
1865Fredrik Lundh. It prevents Python from failing with a stack overflow
1866on Windows.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001867
1868The GC changes resulted in creation of two new slots on object,
1869tp_traverse and tp_clear. The augmented assignment changes result in
Guido van Rossum4338a282000-09-06 13:02:08 +00001870the creation of a new slot for each in-place operator.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001871
1872The GC API creates new requirements for container types implemented in
Guido van Rossum4338a282000-09-06 13:02:08 +00001873C extension modules. See Include/objimpl.h for details.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001874
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001875PyErr_Format has been updated to automatically calculate the size of
1876the buffer needed to hold the formatted result string. This change
1877prevents crashes caused by programmer error.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001878
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001879New C API calls: PyObject_AsFileDescriptor, PyErr_WriteUnraisable.
Guido van Rossume905e952000-09-05 12:42:46 +00001880
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001881PyRun_AnyFileEx, PyRun_SimpleFileEx, PyRun_FileEx -- New functions
1882that are the same as their non-Ex counterparts except they take an
1883extra flag argument that tells them to close the file when done.
1884
1885XXX There were other API changes that should be fleshed out here.
Guido van Rossumab9d6f01998-08-10 22:01:13 +00001886
Tim Peters8b092332000-09-05 20:15:25 +00001887
1888Windows Changes
1889---------------
1890
1891New popen2/popen3/peopen4 in os module (see Changed Modules above).
1892
1893os.popen is much more usable on Windows 95 and 98. See Microsoft
1894Knowledge Base article Q150956. The Win9x workaround described there
1895is implemented by the new w9xpopen.exe helper in the root of your
1896Python installation. Note that Python uses this internally; it is not
1897a standalone program.
1898
1899Administrator privileges are no longer required to install Python
1900on Windows NT or Windows 2000. If you have administrator privileges,
1901Python's registry info will be written under HKEY_LOCAL_MACHINE.
1902Otherwise the installer backs off to writing Python's registry info
Guido van Rossum4338a282000-09-06 13:02:08 +00001903under HKEY_CURRENT_USER. The latter is sufficient for all "normal"
Tim Peters8b092332000-09-05 20:15:25 +00001904uses of Python, but will prevent some advanced uses from working
1905(for example, running a Python script as an NT service, or possibly
1906from CGI).
1907
1908[This was new in 1.6] The installer no longer runs a separate Tcl/Tk
1909installer; instead, it installs the needed Tcl/Tk files directly in the
1910Python directory. If you already have a Tcl/Tk installation, this
1911wastes some disk space (about 4 Megs) but avoids problems with
1912conflicting Tcl/Tk installations, and makes it much easier for Python
1913to ensure that Tcl/Tk can find all its files.
1914
1915[This was new in 1.6] The Windows installer now installs by default in
1916\Python20\ on the default volume, instead of \Program Files\Python-2.0\.
1917
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001918
1919Updates to the changes between 1.5.2 and 1.6
1920--------------------------------------------
1921
1922The 1.6 NEWS file can't be changed after the release is done, so here
1923is some late-breaking news:
1924
1925New APIs in locale.py: normalize(), getdefaultlocale(), resetlocale(),
1926and changes to getlocale() and setlocale().
1927
1928The new module is now enabled per default.
1929
1930It is not true that the encodings codecs cannot be used for normal
1931strings: the string.encode() (which is also present on 8-bit strings
1932!) allows using them for 8-bit strings too, e.g. to convert files from
1933cp1252 (Windows) to latin-1 or vice-versa.
1934
1935Japanese codecs are available from Tamito KAJIYAMA:
1936http://pseudo.grad.sccs.chukyo-u.ac.jp/~kajiyama/python/
1937
1938
Guido van Rossumab9d6f01998-08-10 22:01:13 +00001939======================================================================