blob: 02c4928f7d20f138236983ac859d6547577f47ab [file] [log] [blame]
Tim Peters84362bc2001-10-19 17:55:30 +00001What's New in Python 2.2b2?
2XXX Planned XXX Release date: 14-Nov-2001
3===========================
4
5Type/class unification and new-style classes
6
Tim Petersa427a2b2001-10-29 22:25:45 +00007- The new builtin dictionary() constructor, and dictionary type, have
8 been renamed to dict. This reflects a decade of common usage.
9
Guido van Rossum7ad2d1e2001-10-29 22:11:00 +000010- New-style classes can now have a __del__ method, which is called
11 when the instance is deleted (just like for classic classes).
12
Guido van Rossum12d955c2001-10-26 14:56:06 +000013- Assignment to object.__dict__ is now possible, for objects that are
14 instances of new-style classes that have a __dict__ (unless the base
15 class forbids it).
16
Tim Peters1fc240e2001-10-26 05:06:50 +000017- dictionary() now accepts an iterable object producing 2-sequences.
18 For example, dictionary(d.items()) == d for any dictionary d. The
19 argument, and the elements of the argument, can be any iterable
20 objects.
21
Guido van Rossumc8e56452001-10-22 00:43:43 +000022- Methods of built-in types now properly check for keyword arguments
23 (formerly these were silently ignored). The only built-in methods
24 that take keyword arguments are __call__, __init__ and __new__.
25
Guido van Rossum86443212001-10-27 22:28:54 +000026- The socket function has been converted to a type; see below.
27
Tim Peters84362bc2001-10-19 17:55:30 +000028Core and builtins
29
Guido van Rossum12d955c2001-10-26 14:56:06 +000030- Clarified the error messages for unsupported operands to an operator
31 (like 1 + '').
32
Tim Peters84362bc2001-10-19 17:55:30 +000033Extension modules
34
Guido van Rossum12d955c2001-10-26 14:56:06 +000035- The socket module defines a new method for socket objects,
36 sendall(). This is like send() but may make multiple calls to
Guido van Rossum86443212001-10-27 22:28:54 +000037 send() until all data has been sent. Also, the socket function has
38 been converted to a subclassable type, like list and tuple (etc.)
39 before it; socket and SocketType are now the same thing.
Guido van Rossum12d955c2001-10-26 14:56:06 +000040
41- Various bugfixes to the curses module. There is now a test suite
42 for the curses module (you have to run it manually).
Andrew M. Kuchling15e03532001-10-22 16:37:10 +000043
Guido van Rossum692adf12001-10-30 03:03:03 +000044- binascii.b2a_base64 no longer places an arbitrary restriction of 57
45 bytes on its input.
46
Tim Peters84362bc2001-10-19 17:55:30 +000047Library
48
Tim Peters75335872001-11-03 19:35:43 +000049- Symbolic group names in regular expressions must be unique. For
50 example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
51 single name can't mean both "group 1" and "group 2" simultaneously.
52 Python 2.2 detects this error at regexp compilation time; previously,
53 the error went undetected, and results were unpredictable.
54
Martin v. Löwisb7b32602001-11-02 23:48:20 +000055- Tix exposes more commands through the classes DirSelectBox,
56 DirSelectDialog, ListNoteBook, Meter, CheckList, and the
57 methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
58 tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
59
Tim Peters98791af2001-10-23 01:59:54 +000060- Traceback objects are now scanned by cyclic garbage collection, so
61 cycles created by casual use of sys.exc_info() no longer cause
62 permanent memory leaks (provided garbage collection is enabled).
63
Guido van Rossum49192142001-10-24 20:51:44 +000064- os.extsep -- a new variable needed by the RISCOS support. It is the
65 separator used by extensions, and is '.' on all platforms except
66 RISCOS, where it is '/'. There is no need to use this variable
67 unless you have a masochistic desire to port your code to RISCOS.
68
Tim Peters84362bc2001-10-19 17:55:30 +000069Tools/Demos
70
71Build
72
73C API
74
Tim Peters1fc240e2001-10-26 05:06:50 +000075- New function PySequence_Fast_GET_SIZE() returns the size of a non-
76 NULL result from PySequence_Fast(), more quickly than calling
77 PySequence_Size().
78
Tim Peters84362bc2001-10-19 17:55:30 +000079New platforms
80
Guido van Rossum86443212001-10-27 22:28:54 +000081- We've finally confirmed that this release builds on HP-UX 11.00,
82 *with* threads, and passes the test suite.
83
Guido van Rossum49192142001-10-24 20:51:44 +000084- Updated RISCOS port by Dietmar Schwertberger.
85
Tim Peters84362bc2001-10-19 17:55:30 +000086Tests
87
Andrew M. Kuchling15e03532001-10-22 16:37:10 +000088- Added a test script for the curses module. It isn't run automatically;
89 regrtest.py must be run with '-u curses' to enable it.
90
Tim Peters84362bc2001-10-19 17:55:30 +000091Windows
92
93
Tim Petersabf925f2001-09-28 21:53:42 +000094What's New in Python 2.2b1?
Guido van Rossum1c486092001-10-19 02:05:35 +000095Release date: 19-Oct-2001
Tim Petersabf925f2001-09-28 21:53:42 +000096===========================
97
98Type/class unification and new-style classes
99
Guido van Rossum687ae002001-10-15 22:03:32 +0000100- New-style classes are now always dynamic (except for built-in and
Guido van Rossum3eea25c2001-10-16 00:46:57 +0000101 extension types). There is no longer a performance penalty, and I
Guido van Rossum687ae002001-10-15 22:03:32 +0000102 no longer see another reason to keep this baggage around. One relic
Guido van Rossum3eea25c2001-10-16 00:46:57 +0000103 remains: the __dict__ of a new-style class is a read-only proxy; you
104 must set the class's attribute to modify it. As a consequence, the
Guido van Rossum687ae002001-10-15 22:03:32 +0000105 __defined__ attribute of new-style types no longer exists, for lack
106 of need: there is once again only one __dict__ (although in the
Guido van Rossum3eea25c2001-10-16 00:46:57 +0000107 future a __cache__ may be resurrected with a similar function, if I
108 can prove that it actually speeds things up).
Guido van Rossum50fda3b2001-10-04 19:46:06 +0000109
Tim Peters1c9ca872001-10-04 06:43:12 +0000110- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
111 always returned None, even when there was a class docstring).
112
113- doctest now finds and runs docstrings attached to new-style classes,
114 class methods, static methods, and properties.
115
Guido van Rossum9074ef62001-10-16 21:34:49 +0000116Core and builtins
Tim Petersabf925f2001-09-28 21:53:42 +0000117
Guido van Rossuma8bcf802001-10-15 15:53:58 +0000118- A very subtle syntactical pitfall in list comprehensions was fixed.
119 For example: [a+b for a in 'abc', for b in 'def']. The comma in
120 this example is a mistake. Previously, this would silently let 'a'
121 iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
122 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
123 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
124 Note that [a for a in <singleton>] is a convoluted way to say
125 [<singleton>] anyway, so it's not like any expressiveness is lost.
126
Guido van Rossum9074ef62001-10-16 21:34:49 +0000127- getattr(obj, name, default) now only catches AttributeError, as
128 documented, rather than returning the default value for all
129 exceptions (which could mask bugs in a __getattr__ hook, for
130 example).
131
Fred Drakecb7a6b52001-10-22 18:41:51 +0000132- Weak reference objects are now part of the core and offer a C API.
Fred Drake934d2a42001-10-18 18:18:06 +0000133 A bug which could allow a core dump when binary operations involved
Andrew M. Kuchling51c18162001-10-22 01:47:26 +0000134 proxy reference has been fixed. weakref.ReferenceError is now a
Barry Warsawf6fb1712001-10-19 05:35:40 +0000135 built-in exception.
Fred Drake934d2a42001-10-18 18:18:06 +0000136
Guido van Rossum1c486092001-10-19 02:05:35 +0000137- unicode(obj) now behaves more like str(obj), accepting arbitrary
138 objects, and calling a __unicode__ method if it exists.
139 unicode(obj, encoding) and unicode(obj, encoding, errors) still
Marc-André Lemburgb5507ec2001-10-19 12:02:29 +0000140 require an 8-bit string or character buffer argument.
Guido van Rossum1c486092001-10-19 02:05:35 +0000141
Barry Warsawf6fb1712001-10-19 05:35:40 +0000142- isinstance() now allows any object as the first argument and a
143 class, a type or something with a __bases__ tuple attribute for the
144 second argument. The second argument may also be a tuple of a
145 class, type, or something with __bases__, in which case isinstance()
146 will return true if the first argument is an instance of any of the
147 things contained in the second argument tuple. E.g.
148
149 isinstance(x, (A, B))
150
151 returns true if x is an instance of A or B.
152
Guido van Rossum9074ef62001-10-16 21:34:49 +0000153Extension modules
154
155- thread.start_new_thread() now returns the thread ID (previously None).
156
Martin v. Löwis16dc7f42001-09-30 20:32:11 +0000157- binascii has now two quopri support functions, a2b_qp and b2a_qp.
158
Guido van Rossumc524d952001-10-19 01:31:59 +0000159- readline now supports setting the startup_hook and the
160 pre_event_hook, and adds the add_history() function.
Martin v. Löwis0daad592001-09-30 21:09:59 +0000161
Guido van Rossumc524d952001-10-19 01:31:59 +0000162- os and posix supports chroot(), setgroups() and unsetenv() where
163 available. The stat(), fstat(), statvfs() and fstatvfs() functions
164 now return "pseudo-sequences" -- the various fields can now be
165 accessed as attributes (e.g. os.stat("/").st_mtime) but for
166 backwards compatibility they also behave as a fixed-length sequence.
167 Some platform-specific fields (e.g. st_rdev) are only accessible as
Guido van Rossum98bf58f2001-10-18 20:34:25 +0000168 attributes.
169
170- time: localtime(), gmtime() and strptime() now return a
171 pseudo-sequence similar to the os.stat() return value, with
172 attributes like tm_year etc.
Martin v. Löwis16628c92001-10-04 22:46:41 +0000173
Guido van Rossum9074ef62001-10-16 21:34:49 +0000174- Decompression objects in the zlib module now accept an optional
175 second parameter to decompress() that specifies the maximum amount
176 of memory to use for the uncompressed data.
Tim Petersabf925f2001-09-28 21:53:42 +0000177
Jeremy Hyltoncb441432001-10-19 03:40:19 +0000178- optional SSL support in the socket module now exports OpenSSL
179 functions RAND_add(), RAND_egd(), and RAND_status(). These calls
180 are useful on platforms like Solaris where OpenSSL does not
Barry Warsawf6fb1712001-10-19 05:35:40 +0000181 automatically seed its PRNG. Also, the keyfile and certfile
182 arguments to socket.ssl() are now optional.
183
184- posixmodule (and by extension, the os module on POSIX platforms) now
185 exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
Jeremy Hyltoncb441432001-10-19 03:40:19 +0000186
Guido van Rossum9074ef62001-10-16 21:34:49 +0000187Library
Guido van Rossum3c288632001-10-16 21:13:49 +0000188
Tim Peters7402f792001-10-02 03:53:41 +0000189- doctest now excludes functions and classes not defined by the module
190 being tested, thanks to Tim Hochberg.
191
Fred Drakecb7a6b52001-10-22 18:41:51 +0000192- HotShot, a new profiler implemented using a C-based callback, has
193 been added. This substantially reduces the overhead of profiling,
194 but it is still quite preliminary. Support modules and
195 documentation will be added in upcoming releases (before 2.2 final).
196
Guido van Rossumc4b09b42001-10-04 10:19:00 +0000197- profile now produces correct output in situations where an exception
198 raised in Python is cleared by C code (e.g. hasattr()). This used
199 to cause wrong output, including spurious claims of recursive
200 functions and attribution of time spent to the wrong function.
201
Tim Peters0a1fc4e2001-10-07 03:12:08 +0000202 The code and documentation for the derived OldProfile and HotProfile
203 profiling classes was removed. The code hasn't worked for years (if
204 you tried to use them, they raised exceptions). OldProfile
205 intended to reproduce the behavior of the profiler Python used more
206 than 7 years ago, and isn't interesting anymore. HotProfile intended
207 to provide a faster profiler (but producing less information), and
208 that's a worthy goal we intend to meet via a different approach (but
209 without losing information).
210
Tim Peterscce092d2001-10-09 05:31:56 +0000211- Profile.calibrate() has a new implementation that should deliver
Tim Peters659a6032001-10-09 20:51:19 +0000212 a much better system-specific calibration constant. The constant can
213 now be specified in an instance constructor, or as a Profile class or
214 instance variable, instead of by editing profile.py's source code.
215 Calibration must still be done manually (see the docs for the profile
216 module).
217
218 Note that Profile.calibrate() must be overriden by subclasses.
219 Improving the accuracy required exploiting detailed knowledge of
220 profiler internals; the earlier method abstracted away the details
221 and measured a simplified model instead, but consequently computed
222 a constant too small by a factor of 2 on some modern machines.
Tim Peterscce092d2001-10-09 05:31:56 +0000223
Martin v. Löwis16dc7f42001-09-30 20:32:11 +0000224- quopri's encode and decode methods take an optional header parameter,
Jeremy Hylton6f543b62001-10-16 20:42:52 +0000225 which indicates whether output is intended for the header 'Q'
226 encoding.
227
Guido van Rossuma5343cc2001-10-18 18:02:07 +0000228- The SocketServer.ThreadingMixIn class now closes the request after
229 finish_request() returns. (Not when it errors out though.)
230
Barry Warsawf6fb1712001-10-19 05:35:40 +0000231- The nntplib module's NNTP.body() method has grown a `file' argument
232 to allow saving the message body to a file.
233
234- The email package has added a class email.Parser.HeaderParser which
235 only parses headers and does not recurse into the message's body.
236 Also, the module/class MIMEAudio has been added for representing
237 audio data (contributed by Anthony Baxter).
238
239- ftplib should be able to handle files > 2GB.
240
241- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
242 ON, and OFF.
243
Fred Drakecb7a6b52001-10-22 18:41:51 +0000244- xml.dom.minidom NodeList objects now support the length attribute
245 and item() method as required by the DOM specifications.
246
Guido van Rossumed554f62001-10-02 23:15:37 +0000247Tools/Demos
248
249- Demo/dns was removed. It no longer serves any purpose; a package
250 derived from it is now maintained by Anthony Baxter, see
251 http://PyDNS.SourceForge.net.
Tim Petersabf925f2001-09-28 21:53:42 +0000252
Barry Warsawf6fb1712001-10-19 05:35:40 +0000253- The freeze tool has been made more robust, and two new options have
254 been added: -X and -E.
255
Tim Petersabf925f2001-09-28 21:53:42 +0000256Build
257
Barry Warsawf6fb1712001-10-19 05:35:40 +0000258- configure will use CXX in LINKCC if CXX is used to build main() and
259 the system requires to link a C++ main using the C++ compiler.
260
Tim Petersabf925f2001-09-28 21:53:42 +0000261C API
262
Guido van Rossum6c4bce32001-10-18 19:20:25 +0000263- The documentation for the tp_compare slot is updated to require that
264 the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
265 not correct. This is not yet enforced but will be enforced in
266 Python 2.3; even later, we may use -2 to indicate errors and +2 for
267 "NotImplemented". Right now, -1 should be used for an error return.
268
Tim Petersd38b1c72001-09-30 05:09:37 +0000269- PyLong_AsLongLong() now accepts int (as well as long) arguments.
270 Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
271 as long) arguments.
272
Guido van Rossum3c288632001-10-16 21:13:49 +0000273- PyThread_start_new_thread() now returns a long int giving the thread
274 ID, if one can be calculated; it returns -1 for error, 0 if no
275 thread ID is calculated (this is an incompatible change, but only
276 the thread module used this API). This code has only really been
277 tested on Linux and Windows; other platforms please beware (and
278 report any bugs or strange behavior).
279
Guido van Rossum1c486092001-10-19 02:05:35 +0000280- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
281 input.
282
Tim Petersabf925f2001-09-28 21:53:42 +0000283New platforms
284
285Tests
286
287Windows
288
Tim Peters04cf1d32001-10-09 22:39:40 +0000289- Installer: If you install IDLE, and don't disable file-extension
290 registration, a new "Edit with IDLE" context (right-click) menu entry
291 is created for .py and .pyw files.
292
Tim Peters1ce3cf72001-10-01 17:58:40 +0000293- The signal module now supports SIGBREAK on Windows, thanks to Steven
294 Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
295 action remains to call Win32 ExitProcess(). This can be changed via
296 signal.signal(). For example:
297
298 # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
299 # (SIGINT) behavior.
300 import signal
301 signal.signal(signal.SIGBREAK,
302 signal.default_int_handler)
303
304 try:
305 while 1:
306 pass
307 except KeyboardInterrupt:
308 # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
309 # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
310 # program without the possibility for any Python-level cleanup).
311 print "Clean exit"
312
Tim Petersabf925f2001-09-28 21:53:42 +0000313
Tim Petersb07352e2001-09-08 01:25:47 +0000314What's New in Python 2.2a4?
Barry Warsaw86fbaf82001-09-28 15:26:12 +0000315Release date: 28-Sep-2001
Tim Petersb07352e2001-09-08 01:25:47 +0000316===========================
317
Guido van Rossum808eea72001-09-25 04:15:41 +0000318Type/class unification and new-style classes
319
320- pydoc and inspect are now aware of new-style classes;
321 e.g. help(list) at the interactive prompt now shows proper
322 documentation for all operations on list objects.
323
324- Applications using Jim Fulton's ExtensionClass module can now safely
325 be used with Python 2.2. In particular, Zope 2.4.1 now works with
326 Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
327 examples also work again. It is hoped that Gtk and Boost also work
328 with 2.2a4 and beyond. (If you can confirm this, please write
329 webmaster@python.org; if there are still problems, please open a bug
330 report on SourceForge.)
Tim Petersb07352e2001-09-08 01:25:47 +0000331
Tim Peters66c1a522001-09-24 21:17:50 +0000332- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
333 These map to readonly attributes 'fget', 'fset', 'fdel', and '__doc__'
334 in the constructed property object. fget, fset and fdel weren't
335 discoverable from Python in 2.2a3. __doc__ is new, and allows to
336 associate a docstring with a property.
337
Guido van Rossum808eea72001-09-25 04:15:41 +0000338- Comparison overloading is now more completely implemented. For
339 example, a str subclass instance can properly be compared to a str
340 instance, and it can properly overload comparison. Ditto for most
341 other built-in object types.
342
343- The repr() of new-style classes has changed; instead of <type
344 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
345 *except* for built-in types, which are still rendered as <type
346 'Foo'> (to avoid upsetting existing code that might parse or
347 otherwise rely on repr() of certain type objects).
348
349- The repr() of new-style objects is now always <Foo object at XXX>;
350 previously, it was sometimes <Foo instance at XXX>.
351
352- For new-style classes, what was previously called __getattr__ is now
353 called __getattribute__. This method, if defined, is called for
Andrew M. Kuchling51c18162001-10-22 01:47:26 +0000354 *every* attribute access. A new __getattr__ hook more similar to the
Guido van Rossum808eea72001-09-25 04:15:41 +0000355 one in classic classes is defined which is called only if regular
356 attribute access raises AttributeError; to catch *all* attribute
357 access, you can use __getattribute__ (for new-style classes). If
358 both are defined, __getattribute__ is called first, and if it raises
359 AttributeError, __getattr__ is called.
360
361- The __class__ attribute of new-style objects can be assigned to.
362 The new class must have the same C-level object layout as the old
363 class.
364
365- The builtin file type can be subclassed now. In the usual pattern,
366 "file" is the name of the builtin type, and file() is a new builtin
367 constructor, with the same signature as the builtin open() function.
368 file() is now the preferred way to open a file.
369
370- Previously, __new__ would only see sequential arguments passed to
371 the type in a constructor call; __init__ would see both sequential
372 and keyword arguments. This made no sense whatsoever any more, so
373 now both __new__ and __init__ see all arguments.
374
375- Previously, hash() applied to an instance of a subclass of str or
376 unicode always returned 0. This has been repaired.
377
378- Previously, an operation on an instance of a subclass of an
379 immutable type (int, long, float, complex, tuple, str, unicode),
380 where the subtype didn't override the operation (and so the
381 operation was handled by the builtin type), could return that
382 instance instead a value of the base type. For example, if s was of
383 a str sublass type, s[:] returned s as-is. Now it returns a str
384 with the same value as s.
385
Barry Warsaw86fbaf82001-09-28 15:26:12 +0000386- Provisional support for pickling new-style objects has been added.
387
Guido van Rossum808eea72001-09-25 04:15:41 +0000388Core
389
Tim Peters2c9aa5e2001-09-23 04:06:05 +0000390- file.writelines() now accepts any iterable object producing strings.
391
Marc-André Lemburgaefd7662001-09-20 12:59:37 +0000392- PyUnicode_FromEncodedObject() now works very much like
393 PyObject_Str(obj) in that it tries to use __str__/tp_str
394 on the object if the object is not a string or buffer. This
395 makes unicode() behave like str() when applied to non-string/buffer
396 objects.
397
Andrew M. Kuchling51c18162001-10-22 01:47:26 +0000398- PyFile_WriteObject now passes Unicode objects to the file's write
399 method. As a result, all file-like objects which may be the target
Martin v. Löwis2777c022001-09-19 13:47:32 +0000400 of a print statement must support Unicode objects, i.e. they must
401 at least convert them into ASCII strings.
402
Guido van Rossum624c8af2001-09-18 15:21:04 +0000403- Thread scheduling on Solaris should be improved; it is no longer
404 necessary to insert a small sleep at the start of a thread in order
405 to let other runnable threads be scheduled.
406
Tim Petersb07352e2001-09-08 01:25:47 +0000407Library
408
Marc-André Lemburgbf990172001-09-27 14:17:33 +0000409- StringIO.StringIO instances and cStringIO.StringIO instances support
410 read character buffer compatible objects for their .write() methods.
411 These objects are converted to strings and then handled as such
412 by the instances.
413
Barry Warsaw2f600732001-09-24 04:28:10 +0000414- The "email" package has been added. This is basically a port of the
415 mimelib package <http://sf.net/projects/mimelib> with API changes
416 and some implementations updated to use iterators and generators.
417
Tim Peters8a9c2842001-09-22 21:30:22 +0000418- difflib.ndiff() and difflib.Differ.compare() are generators now. This
419 restores the ability of Tools/scripts/ndiff.py to start producing output
420 before the entire comparison is complete.
421
Barry Warsaw58b072d2001-09-22 04:44:21 +0000422- StringIO.StringIO instances and cStringIO.StringIO instances support
423 iteration just like file objects (i.e. their .readline() method is
424 called for each iteration until it returns an empty string).
425
Marc-André Lemburg494f2ae2001-09-19 11:33:31 +0000426- The codecs module has grown four new helper APIs to access
427 builtin codecs: getencoder(), getdecoder(), getreader(),
428 getwriter().
429
Guido van Rossum624c8af2001-09-18 15:21:04 +0000430- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
431 simplifies writing XML RPC servers.
432
Barry Warsaw647d5e82001-09-28 17:01:02 +0000433- os.path.realpath(): a new function that returns the absolute pathname
Guido van Rossum624c8af2001-09-18 15:21:04 +0000434 after interpretation of symbolic links. On non-Unix systems, this
435 is an alias for os.path.abspath().
436
Tim Peters16a77ad2001-09-08 04:00:12 +0000437- operator.indexOf() (PySequence_Index() in the C API) now works with any
438 iterable object.
439
Guido van Rossum624c8af2001-09-18 15:21:04 +0000440- smtplib now supports various authentication and security features of
441 the SMTP protocol through the new login() and starttls() methods.
Guido van Rossumd8185ca2001-09-14 16:35:16 +0000442
Guido van Rossum624c8af2001-09-18 15:21:04 +0000443- hmac: a new module implementing keyed hashing for message
444 authentication.
445
446- mimetypes now recognizes more extensions and file types. At the
447 same time, some mappings not sanctioned by IANA were removed.
Guido van Rossumd8185ca2001-09-14 16:35:16 +0000448
Guido van Rossum624c8af2001-09-18 15:21:04 +0000449- The "compiler" package has been brought up to date to the state of
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +0000450 Python 2.2 bytecode generation. It has also been promoted from a
451 Tool to a standard library package. (Tools/compiler still exists as
452 a sample driver.)
453
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +0000454Tools
Guido van Rossum624c8af2001-09-18 15:21:04 +0000455
Tim Petersb07352e2001-09-08 01:25:47 +0000456Build
457
Guido van Rossum624c8af2001-09-18 15:21:04 +0000458- Large file support (LFS) is now automatic when the platform supports
459 it; no more manual configuration tweaks are needed. On Linux, at
460 least, it's possible to have a system whose C library supports large
461 files but whose kernel doesn't; in this case, large file support is
462 still enabled but doesn't do you any good unless you upgrade your
463 kernel or share your Python executable with another system whose
464 kernel has large file support.
465
466- The configure script now supplies plausible defaults in a
467 cross-compilation environment. This doesn't mean that the supplied
468 values are always correct, or that cross-compilation now works
469 flawlessly -- but it's a first step (and it shuts up most of
470 autoconf's warnings about AC_TRY_RUN).
471
472- The Unix build is now a bit less chatty, courtesy of the parser
473 generator. The build is completely silent (except for errors) when
474 using "make -s", thanks to a -q option to setup.py.
475
Tim Petersb07352e2001-09-08 01:25:47 +0000476C API
477
Guido van Rossum624c8af2001-09-18 15:21:04 +0000478- The "structmember" API now supports some new flag bits to deny read
479 and/or write access to attributes in restricted execution mode.
480
Tim Petersb07352e2001-09-08 01:25:47 +0000481New platforms
482
Guido van Rossum624c8af2001-09-18 15:21:04 +0000483- Compaq's iPAQ handheld, running the "familiar" Linux distribution
484 (http://familiar.handhelds.org).
485
Tim Petersb07352e2001-09-08 01:25:47 +0000486Tests
487
Tim Peters8a9c2842001-09-22 21:30:22 +0000488- The "classic" standard tests, which work by comparing stdout to
489 an expected-output file under Lib/test/output/, no longer stop at
490 the first mismatch. Instead the test is run to completion, and a
491 variant of ndiff-style comparison is used to report all differences.
492 This is much easier to understand than the previous style of reporting.
493
494- The unittest-based standard tests now use regrtest's test_main()
495 convention, instead of running as a side-effect of merely being
496 imported. This allows these tests to be run in more natural and
497 flexible ways as unittests, outside the regrtest framework.
498
499- regrtest.py is much better integrated with unittest and doctest now,
500 especially in regard to reporting errors.
501
Tim Petersb07352e2001-09-08 01:25:47 +0000502Windows
503
Guido van Rossum624c8af2001-09-18 15:21:04 +0000504- Large file support now also works for files > 4GB, on filesystems
Tim Peters8a9c2842001-09-22 21:30:22 +0000505 that support it (NTFS under Windows 2000). See "What's New in
506 Python 2.2a3" for more detail.
Guido van Rossum624c8af2001-09-18 15:21:04 +0000507
Tim Petersb07352e2001-09-08 01:25:47 +0000508
Tim Petersedc99312001-08-22 21:36:50 +0000509What's New in Python 2.2a3?
Barry Warsaw86fbaf82001-09-28 15:26:12 +0000510Release Date: 07-Sep-2001
Tim Petersedc99312001-08-22 21:36:50 +0000511===========================
512
513Core
514
Tim Peters9fffa3e2001-09-04 05:14:19 +0000515- Conversion of long to float now raises OverflowError if the long is too
516 big to represent as a C double.
517
Tim Peters32f453e2001-09-03 08:35:41 +0000518- The 3-argument builtin pow() no longer allows a third non-None argument
519 if either of the first two arguments is a float, or if both are of
520 integer types and the second argument is negative (in which latter case
521 the arguments are converted to float, so this is really the same
522 restriction).
523
Tim Peters5d2b77c2001-09-03 05:47:38 +0000524- The builtin dir() now returns more information, and sometimes much
525 more, generally naming all attributes of an object, and all attributes
526 reachable from the object via its class, and from its class's base
527 classes, and so on from them too. Example: in 2.2a2, dir([]) returned
528 an empty list. In 2.2a3,
529
530 >>> dir([])
531 ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
532 '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
533 '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
534 '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
535 '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
536 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
537 'reverse', 'sort']
538
539 dir(module) continues to return only the module's attributes, though.
540
Tim Petersbdee63f2001-09-02 03:40:59 +0000541- Overflowing operations on plain ints now return a long int rather
Guido van Rossumae457142001-08-31 18:31:35 +0000542 than raising OverflowError. This is a partial implementation of PEP
543 237. You can use -Wdefault::OverflowWarning to enable a warning for
544 this situation, and -Werror::OverflowWarning to revert to the old
545 OverflowError exception.
546
Guido van Rossum61c345f2001-09-04 03:26:15 +0000547- A new command line option, -Q<arg>, is added to control run-time
Guido van Rossumae457142001-08-31 18:31:35 +0000548 warnings for the use of classic division. (See PEP 238.) Possible
Barry Warsawd6c8ca62001-09-07 18:13:44 +0000549 values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
550 -Qold, meaning the / operator has its classic meaning and no
551 warnings are issued. Using -Qwarn issues a run-time warning about
552 all uses of classic division for int and long arguments; -Qwarnall
553 also warns about classic division for float and complex arguments
554 (for use with fixdiv.py). Using -Qnew is questionable; it turns on
555 new division by default, but only in the __main__ module. You can
556 usefully combine -Qwarn or -Qwarnall and -Qnew: this gives the
557 __main__ module new division, and warns about classic division
558 everywhere else.
Guido van Rossumae457142001-08-31 18:31:35 +0000559
Tim Petersbdee63f2001-09-02 03:40:59 +0000560- Many built-in types can now be subclassed. This applies to int,
Guido van Rossumae457142001-08-31 18:31:35 +0000561 long, float, str, unicode, and tuple. (The types complex, list and
562 dictionary can also be subclassed; this was introduced earlier.)
563 Note that restrictions apply when subclassing immutable built-in
564 types: you can only affect the value of the instance by overloading
565 __new__. You can add mutable attributes, and the subclass instances
566 will have a __dict__ attribute, but you cannot change the "value"
567 (as implemented by the base class) of an immutable subclass instance
568 once it is created.
569
Guido van Rossumaaf80c82001-09-02 13:44:35 +0000570- The dictionary constructor now takes an optional argument, a
571 mapping-like object, and initializes the dictionary from its
572 (key, value) pairs.
573
Tim Petersbdee63f2001-09-02 03:40:59 +0000574- A new built-in type, super, has been added. This facilitates making
Guido van Rossumae457142001-08-31 18:31:35 +0000575 "cooperative super calls" in a multiple inheritance setting. For an
576 explanation, see http://www.python.org/2.2/descrintro.html#cooperation
577
Guido van Rossum8d7234d2001-09-06 22:02:58 +0000578- A new built-in type, property, has been added. This enables the
579 creation of "properties". These are attributes implemented by
580 getter and setter functions (or only one of these for read-only or
581 write-only attributes), without the need to override __getattr__.
582 See http://www.python.org/2.2/descrintro.html#property
Guido van Rossumae457142001-08-31 18:31:35 +0000583
Tim Petersbdee63f2001-09-02 03:40:59 +0000584- The syntax of floating-point and imaginary literals has been
Tim Petersd507dab2001-08-30 20:51:59 +0000585 liberalized, to allow leading zeroes. Examples of literals now
586 legal that were SyntaxErrors before:
587
588 00.0 0e3 0100j 07.5 00000000000000000008.
589
Tim Petersbdee63f2001-09-02 03:40:59 +0000590- An old tokenizer bug allowed floating point literals with an incomplete
Tim Petersc6d95812001-08-28 20:56:27 +0000591 exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
592
Tim Petersedc99312001-08-22 21:36:50 +0000593Library
594
Martin v. Löwiscb227c92001-09-06 08:54:16 +0000595- telnetlib includes symbolic names for the options, and support for
596 setting an option negotiation callback.
597
Tim Petersa40c7932001-09-05 22:36:56 +0000598- The new C standard no longer requires that math libraries set errno to
599 ERANGE on overflow. For platform libraries that exploit this new
600 freedom, Python's overflow-checking was wholly broken. A new overflow-
601 checking scheme attempts to repair that, but may not be reliable on all
602 platforms (C doesn't seem to provide anything both useful and portable
603 in this area anymore).
604
Martin v. Löwis44f86962001-09-05 13:44:54 +0000605- Asynchronous timeout actions are available through the new class
606 threading.Timer.
607
Tim Peters78526162001-09-05 00:53:45 +0000608- math.log and math.log10 now return sensible results for even huge
609 long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
610
Tim Petersbdee63f2001-09-02 03:40:59 +0000611- A new function, imp.lock_held(), returns 1 when the import lock is
Tim Peters69232342001-08-30 05:16:13 +0000612 currently held. See the docs for the imp module.
613
Tim Petersbdee63f2001-09-02 03:40:59 +0000614- pickle, cPickle and marshal on 32-bit platforms can now correctly read
Tim Peters82112372001-08-29 02:28:42 +0000615 dumps containing ints written on platforms where Python ints are 8 bytes.
616 When read on a box where Python ints are 4 bytes, such values are
617 converted to Python longs.
618
Tim Petersbdee63f2001-09-02 03:40:59 +0000619- In restricted execution mode (using the rexec module), unmarshalling
Guido van Rossumae457142001-08-31 18:31:35 +0000620 code objects is no longer allowed. This plugs a security hole.
621
Steve Purcell6091cd62001-09-06 16:05:17 +0000622- unittest.TestResult instances no longer store references to tracebacks
623 generated by test failures. This prevents unexpected dangling references
624 to objects that should be garbage collected between tests.
625
Tim Petersedc99312001-08-22 21:36:50 +0000626Tools
627
Barry Warsawd6c8ca62001-09-07 18:13:44 +0000628- Tools/scripts/fixdiv.py has been added which can be used to fix
629 division operators as per PEP 238.
630
Tim Petersedc99312001-08-22 21:36:50 +0000631Build
632
Barry Warsawd6c8ca62001-09-07 18:13:44 +0000633- If you are an adventurous person using Mac OS X you may want to look at
634 Mac/OSX. There is a Makefile there that will build Python as a real Mac
635 application, which can be used for experimenting with Carbon or Cocoa.
636 Discussion of this on pythonmac-sig, please.
637
Tim Peters7eea37e2001-09-04 22:08:56 +0000638C API
639
640- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
Tim Peters69232342001-08-30 05:16:13 +0000641
Tim Peters9fffa3e2001-09-04 05:14:19 +0000642- Note that PyLong_AsDouble can fail! This has always been true, but no
643 callers checked for it. It's more likely to fail now, because overflow
644 errors are properly detected now. The proper way to check:
645
646 double x = PyLong_AsDouble(some_long_object);
647 if (x == -1.0 && PyErr_Occurred()) {
648 /* The conversion failed. */
649 }
650
Tim Petersbdee63f2001-09-02 03:40:59 +0000651- The GC API has been changed. Extensions that use the old API will still
Neil Schemenauer4042c692001-08-30 15:38:01 +0000652 compile but will not participate in GC. To upgrade an extension
653 module:
654
655 - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
Tim Petersd507dab2001-08-30 20:51:59 +0000656
Neil Schemenauer4042c692001-08-30 15:38:01 +0000657 - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
658 PyObject_GC_Del to deallocate them
Tim Petersd507dab2001-08-30 20:51:59 +0000659
Neil Schemenauer4042c692001-08-30 15:38:01 +0000660 - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
661 to PyObject_GC_UnTrack
Tim Petersd507dab2001-08-30 20:51:59 +0000662
Neil Schemenauer4042c692001-08-30 15:38:01 +0000663 - remove PyGC_HEAD_SIZE from object size calculations
664
665 - remove calls to PyObject_AS_GC and PyObject_FROM_GC
666
Tim Petersbdee63f2001-09-02 03:40:59 +0000667- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
Guido van Rossumae457142001-08-31 18:31:35 +0000668 These can be used safely to construct string objects from a
669 sprintf-style format string (similar to the format string supported
670 by PyErr_Format()).
Tim Peters69232342001-08-30 05:16:13 +0000671
Tim Petersedc99312001-08-22 21:36:50 +0000672New platforms
673
Tim Petersb7da0902001-09-02 23:01:43 +0000674- Stephen Hansen contributed patches sufficient to get a clean compile
675 under Borland C (Windows), but he reports problems running it and ran
676 out of time to complete the port. Volunteers? Expect a MemoryError
677 when importing the types module; this is probably shallow, and
678 causing later failures too.
Tim Petersbdee63f2001-09-02 03:40:59 +0000679
Tim Petersedc99312001-08-22 21:36:50 +0000680Tests
681
682Windows
683
Tim Peters6e13a562001-09-06 00:32:15 +0000684- Large file support is now enabled on Win32 platforms as well as on
685 Win64. This means that, for example, you can use f.tell() and f.seek()
686 to manipulate files larger than 2 gigabytes (provided you have enough
687 disk space, and are using a Windows filesystem that supports large
Tim Peters9a9471c2001-09-11 23:18:51 +0000688 partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
689 filesize limit, and large file support makes no difference there.
690 FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
691 NTFS has no practical limit on file size, and files of any size can be
692 used from Python now.
Tim Peters6e13a562001-09-06 00:32:15 +0000693
Tim Petersbdee63f2001-09-02 03:40:59 +0000694- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
Tim Peters402d5982001-08-27 06:37:48 +0000695 points to command.com (patch from Brian Quinlan).
696
Tim Petersedc99312001-08-22 21:36:50 +0000697
Tim Peters20f51a72001-07-21 02:31:40 +0000698What's New in Python 2.2a2?
Barry Warsaw86fbaf82001-09-28 15:26:12 +0000699Release Date: 22-Aug-2001
Tim Peters20f51a72001-07-21 02:31:40 +0000700===========================
701
Martin v. Löwis339d0f72001-08-17 18:39:25 +0000702Build
703
Barry Warsaw18b2ecf2001-08-22 20:26:56 +0000704- Tim Peters developed a brand new Windows installer using Wise 8.1,
705 generously donated to us by Wise Solutions.
706
Martin v. Löwis339d0f72001-08-17 18:39:25 +0000707- configure supports a new option --enable-unicode, with the values
708 ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
709 type and supporting code is completely removed from the interpreter.
Barry Warsaw6f3410d2001-08-22 04:08:41 +0000710
Jack Jansen32ce0cd2001-08-21 19:28:20 +0000711- A new configure option --enable-framework builds a Mac OS X framework,
712 which "make frameworkinstall" will install. This provides a starting
713 point for more mac-like functionality, join pythonmac-sig@python.org
714 if you are interested in helping.
Martin v. Löwis339d0f72001-08-17 18:39:25 +0000715
Barry Warsaw6f3410d2001-08-22 04:08:41 +0000716- The NeXT platform is no longer supported.
717
718- The `new' module is now statically linked.
719
Tim Peters0afb6092001-08-15 06:06:44 +0000720Tools
721
722- The new Tools/scripts/cleanfuture.py can be used to automatically
Andrew M. Kuchlingb0532092001-08-15 15:54:56 +0000723 edit out obsolete future statements from Python source code. See
Tim Peters0afb6092001-08-15 06:06:44 +0000724 the module docstring for details.
725
Tim Peters20f51a72001-07-21 02:31:40 +0000726Tests
727
Tim Peters5e824c32001-08-12 22:25:01 +0000728- regrtest.py now knows which tests are expected to be skipped on some
Barry Warsaw6f3410d2001-08-22 04:08:41 +0000729 platforms, allowing to give clearer test result output. regrtest
730 also has optional --use/-u switch to run normally disabled tests
731 which require network access or consume significant disk resources.
Tim Peters5e824c32001-08-12 22:25:01 +0000732
Tim Peters20f51a72001-07-21 02:31:40 +0000733- Several new tests in the standard test suite, with special thanks to
734 Nick Mathewson.
735
736Core
737
Barry Warsaw6f3410d2001-08-22 04:08:41 +0000738- The floor division operator // has been added as outlined in PEP
739 238. The / operator still provides classic division (and will until
740 Python 3.0) unless "from __future__ import division" is included, in
741 which case the / operator will provide true division. The operator
742 module provides truediv() and floordiv() functions. Augmented
743 assignment variants are included, as are the equivalent overloadable
744 methods and C API methods. See the PEP for a full discussion:
745 <http://python.sf.net/peps/pep-0238.html>
746
Tim Peters6cd6a822001-08-17 22:11:27 +0000747- Future statements are now effective in simulated interactive shells
748 (like IDLE). This should "just work" by magic, but read Michael
749 Hudson's "Future statements in simulated shells" PEP 264 for full
750 details: <http://python.sf.net/peps/pep-0264.html>.
751
Guido van Rossumf86ddd22001-08-17 21:21:04 +0000752- The type/class unification (PEP 252-253) was integrated into the
753 trunk and is not so tentative any more (the exact specification of
754 some features is still tentative). A lot of work has done on fixing
755 bugs and adding robustness and features (performance still has to
756 come a long way).
757
Marc-André Lemburg888fac02001-07-31 14:24:31 +0000758- Warnings about a mismatch in the Python API during extension import
759 now use the Python warning framework (which makes it possible to
760 write filters for these warnings).
761
Barry Warsaw9b3be7f2001-08-14 18:35:02 +0000762- A function's __dict__ (aka func_dict) will now always be a
763 dictionary. It used to be possible to delete it or set it to None,
764 but now both actions raise TypeErrors. It is still legal to set it
765 to a dictionary object. Getting func.__dict__ before any attributes
766 have been assigned now returns an empty dictionary instead of None.
767
Guido van Rossum32aa5d22001-09-05 18:43:35 +0000768- A new command line option, -E, was added which disables the use of
769 all environment variables, or at least those that are specifically
770 significant to Python. Usually those have a name starting with
771 "PYTHON". This was used to fix a problem where the tests fail if
772 the user happens to have PYTHONHOME or PYTHONPATH pointing to an
773 older distribution.
774
Marc-André Lemburgd6277912001-07-31 14:42:42 +0000775Library
776
Tim Peters5e824c32001-08-12 22:25:01 +0000777- New class Differ and new functions ndiff() and restore() in difflib.py.
778 These package the algorithms used by the popular Tools/scripts/ndiff.py,
Tim Peters0afb6092001-08-15 06:06:44 +0000779 for programmatic reuse.
Tim Peters5e824c32001-08-12 22:25:01 +0000780
Marc-André Lemburgd6277912001-07-31 14:42:42 +0000781- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
782 value using the minimal quoting required for the value; more
783 reliable than using xml.sax.saxutils.escape() for attribute values.
784
785- Readline completion support for cmd.Cmd was added.
786
Barry Warsaw6f3410d2001-08-22 04:08:41 +0000787- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
788
789- Added function threading.BoundedSemaphore()
790
791- Added Ka-Ping Yee's cgitb.py module.
792
793- The `new' module now exposes the CO_xxx flags.
794
Marc-André Lemburgd6277912001-07-31 14:42:42 +0000795New platforms
796
797C API
798
Marc-André Lemburg888fac02001-07-31 14:24:31 +0000799- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
800 which provide a cross-platform implementations for the
801 relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
802 the standard sprintf() and vsprintf() C lib APIs, these versions
803 apply bounds checking on the used buffer which enhances protection
804 against buffer overruns.
805
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +0000806- Unicode APIs now use name mangling to assure that mixing interpreters
Tim Petersc1731372001-08-04 08:12:36 +0000807 and extensions using different Unicode widths is rendered next to
808 impossible. Trying to import an incompatible Unicode-aware extension
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +0000809 will result in an ImportError. Unicode extensions writers must make
810 sure to check the Unicode width compatibility in their extensions by
811 using at least one of the mangled Unicode APIs in the extension.
812
Martin v. Löwis339d0f72001-08-17 18:39:25 +0000813- Two new flags METH_NOARGS and METH_O are available in method definition
814 tables to simplify implementation of methods with no arguments and a
815 single untyped argument. Calling such methods is more efficient than
816 calling corresponding METH_VARARGS methods. METH_OLDARGS is now
817 deprecated.
818
Tim Petersc1731372001-08-04 08:12:36 +0000819Windows
820
821- "import module" now compiles module.pyw if it exists and nothing else
822 relevant is found.
823
Tim Peters20f51a72001-07-21 02:31:40 +0000824
Guido van Rossum55a78992001-07-17 17:22:32 +0000825What's New in Python 2.2a1?
Barry Warsawd970fe42001-10-25 21:53:30 +0000826Release date: 18-Jul-2001
Tim Petersf553f892001-05-01 20:45:31 +0000827===========================
828
829Core
Tim Petersa814db52001-05-14 07:05:58 +0000830
Tim Peters6d6c1a32001-08-02 04:15:00 +0000831- TENTATIVELY, a large amount of code implementing much of what's
832 described in PEP 252 (Making Types Look More Like Classes) and PEP
833 253 (Subtyping Built-in Types) was added. This will be released
834 with Python 2.2a1. Documentation will be provided separately
835 through http://www.python.org/2.2/. The purpose of releasing this
836 with Python 2.2a1 is to test backwards compatibility. It is
837 possible, though not likely, that a decision is made not to release
838 this code as part of 2.2 final, if any serious backwards
839 incompapatibilities are found during alpha testing that cannot be
840 repaired.
841
Guido van Rossum55a78992001-07-17 17:22:32 +0000842- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +0000843 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +0000844 more 'yield' statements. See PEP 255. Since this adds a new
845 keyword to the language, this feature must be enabled by including a
846 future statement: "from __future__ import generators" (see PEP 236).
847 Generators will become a standard feature in a future release
848 (probably 2.3). Without this future statement, 'yield' remains an
849 ordinary identifier, but a warning is issued each time it is used.
850 (These warnings currently don't conform to the warnings framework of
851 PEP 230; we intend to fix this in 2.2a2.)
852
Marc-André Lemburg12e74b32001-05-22 08:58:23 +0000853- The UTF-16 codec was modified to be more RFC compliant. It will now
854 only remove BOM characters at the start of the string and then
855 only if running in native mode (UTF-16-LE and -BE won't remove a
856 leading BMO character).
857
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +0000858- Strings now have a new method .decode() to complement the already
859 existing .encode() method. These two methods provide direct access
860 to the corresponding decoders and encoders of the registered codecs.
861
862 To enhance the usability of the .encode() method, the special
863 casing of Unicode object return values was dropped (Unicode objects
864 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +0000865
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +0000866 Both methods will now return whatever the codec in charge of the
867 requested encoding returns as object, e.g. Unicode codecs will
868 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
869 will return u"äöü"). This enables codec writer to create codecs
870 for various simple to use conversions.
871
872 New codecs were added to demonstrate these new features (the .encode()
873 and .decode() columns indicate the type of the returned objects):
874
875 Name | .encode() | .decode() | Description
876 ----------------------------------------------------------------------
877 uu | string | string | UU codec (e.g. for email)
878 base64 | string | string | base64 codec
Guido van Rossumc3415802001-06-06 13:30:54 +0000879 quopri | string | string | quoted-printable codec
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +0000880 zlib | string | string | zlib compression
881 hex | string | string | 2-byte hex codec
882 rot-13 | string | Unicode | ROT-13 Unicode charmap codec
883
Mark Hammond2a0af792001-05-14 03:09:36 +0000884- Some operating systems now support the concept of a default Unicode
885 encoding for file system operations. Notably, Windows supports 'mbcs'
886 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +0000887 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +0000888 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +0000889
890 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +0000891 functions that return filenames (such as os.listdir()) to return Python
892 string objects pre-encoded using the default file system encoding for
893 the platform. As this encoding is likely to be different from Python's
894 default encoding, converting this name to a Unicode object before passing
895 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +0000896 would attempt to use its default encoding (generally ASCII) rather than
897 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +0000898
Tim Petersa814db52001-05-14 07:05:58 +0000899 In general, this change simply removes surprises when working with
900 Unicode and the file system, making these operations work as you expect,
901 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +0000902 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +0000903
Tim Peters61dff2b2001-05-08 15:43:37 +0000904- Float (and complex) literals in source code were evaluated to full
905 precision only when running from a .py file; the same code loaded from a
906 .pyc (or .pyo) file could suffer numeric differences starting at about the
907 12th significant decimal digit. For example, on a machine with IEEE-754
908 floating arithmetic,
909
910 x = 9007199254740992.0
911 print long(x)
912
913 printed 9007199254740992 if run directly from .py, but 9007199254740000
914 if from a compiled (.pyc or .pyo) file. This was due to marshal using
915 str(float) instead of repr(float) when building code objects. marshal
916 now uses repr(float) instead, which should reproduce floats to full
917 machine precision (assuming the platform C float<->string I/O conversion
918 functions are of good quality).
919
920 This may cause floating-point results to change in some cases, and
921 usually for the better, but may also cause numerically unstable
922 algorithms to break.
923
Tim Peters2f228e72001-05-13 00:19:31 +0000924- The implementation of dicts suffers fewer collisions, which has speed
925 benefits. However, the order in which dict entries appear in dict.keys(),
926 dict.values() and dict.items() may differ from previous releases for a
927 given dict. Nothing is defined about this order, so no program should
928 rely on it. Nevertheless, it's easy to write test cases that rely on the
929 order by accident, typically because of printing the str() or repr() of a
930 dict to an "expected results" file. See Lib/test/test_support.py's new
931 sortdict(dict) function for a simple way to display a dict in sorted
932 order.
933
Tim Peters7a3bfc32001-06-12 01:22:22 +0000934- Many other small changes to dicts were made, resulting in faster
935 operation along the most common code paths.
936
Guido van Rossum10315822001-05-01 20:54:30 +0000937- Dictionary objects now support the "in" operator: "x in dict" means
938 the same as dict.has_key(x).
939
Barry Warsaw51acc8d2001-06-26 20:12:50 +0000940- The update() method of dictionaries now accepts generic mapping
941 objects. Specifically the argument object must support the .keys()
942 and __getitem__() methods. This allows you to say, for example,
943 {}.update(UserDict())
944
Guido van Rossum10315822001-05-01 20:54:30 +0000945- Iterators were added; this is a generalized way of providing values
946 to a for loop. See PEP 234. There's a new built-in function iter()
947 to return an iterator. There's a new protocol to get the next value
948 from an iterator using the next() method (in Python) or the
949 tp_iternext slot (in C). There's a new protocol to get iterators
950 using the __iter__() method (in Python) or the tp_iter slot (in C).
951 Iterating (i.e. a for loop) over a dictionary generates its keys.
952 Iterating over a file generates its lines.
953
Tim Petersf553f892001-05-01 20:45:31 +0000954- The following functions were generalized to work nicely with iterator
955 arguments:
Tim Peterse63415e2001-05-08 04:38:29 +0000956 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +0000957 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
958 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +0000959 join() method of strings
960 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +0000961 'x in y' and 'x not in y' (PySequence_Contains() in C API)
962 operator.countOf() (PySequence_Count() in C API)
Tim Petersd6d010b2001-06-21 02:49:55 +0000963 right-hand side of assignment statements with multiple targets, such as
964 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +0000965
Tim Petersd85e1022001-05-11 21:51:48 +0000966- Accessing module attributes is significantly faster (for example,
967 random.random or os.path or yourPythonModule.yourAttribute).
968
Tim Peterse63415e2001-05-08 04:38:29 +0000969- Comparing dictionary objects via == and != is faster, and now works even
970 if the keys and values don't support comparisons other than ==.
971
Tim Peters95bf9392001-05-10 08:32:44 +0000972- Comparing dictionaries in ways other than == and != is slower: there were
973 insecurities in the dict comparison implementation that could cause Python
974 to crash if the element comparison routines for the dict keys and/or
975 values mutated the dicts. Making the code bulletproof slowed it down.
976
Tim Peterseb28ef22001-06-02 05:27:19 +0000977- Collisions in dicts are resolved via a new approach, which can help
978 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +0000979 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +0000980 faster now. Thanks to Christian Tismer for pointing out the cause and
981 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +0000982
Tim Peters52e155e2001-06-16 05:42:57 +0000983- repr() is much faster for large containers (dict, list, tuple).
984
985
Tim Petersa814db52001-05-14 07:05:58 +0000986Library
987
Fred Drake960fdf92001-07-20 18:38:26 +0000988- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
989 were added to the string module. These a locale-indenpendent
990 constants, unlike letters, lowercase, and uppercase. These are now
991 use in appropriate locations in the standard library.
992
Martin v. Löwisf0473d52001-07-18 16:17:16 +0000993- The flags used in dlopen calls can now be configured using
994 sys.setdlopenflags and queried using sys.getdlopenflags.
995
Guido van Rossumc7e4aca2001-07-12 11:54:37 +0000996- Fredrik Lundh's xmlrpclib is now a standard library module. This
997 provides full client-side XML-RPC support. In addition,
998 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
999 one asyncore-based). Thanks to Eric Raymond for the documentation.
1000
Guido van Rossum643d3912001-07-05 14:46:25 +00001001- The xrange() object is simplified: it no longer supports slicing,
1002 repetition, comparisons, efficient 'in' checking, the tolist()
1003 method, or the start, stop and step attributes. See PEP 260.
1004
Martin v. Löwisebf94db2001-06-06 06:25:40 +00001005- A new function fnmatch.filter to filter lists of file names was added.
1006
Barry Warsawffd674d2001-05-22 16:00:10 +00001007- calendar.py uses month and day names based on the current locale.
1008
Guido van Rossum2e0a6542001-05-15 02:14:44 +00001009- strop is now *really* obsolete (this was announced before with 1.6),
1010 and issues DeprecationWarning when used (except for the four items
1011 that are still imported into string.py).
1012
Tim Petersa814db52001-05-14 07:05:58 +00001013- Cookie.py now sorts key+value pairs by key in output strings.
1014
1015- pprint.isrecursive(object) didn't correctly identify recursive objects.
1016 Now it does.
1017
Tim Peters95b3f782001-05-14 18:39:41 +00001018- pprint functions now much faster for large containers (tuple, list, dict).
1019
Tim Peters7b9542a2001-06-10 23:40:19 +00001020- New 'q' and 'Q' format codes in the struct module, corresponding to C
1021 types "long long" and "unsigned long long" (on Windows, __int64). In
1022 native mode, these can be used only when the platform C compiler supports
1023 these types (when HAVE_LONG_LONG is #define'd by the Python config
1024 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +00001025 In standard mode, 'q' and 'Q' are supported on all platforms, and are
1026 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +00001027
Guido van Rossum83213cc2001-06-12 16:48:52 +00001028- The site module installs a new built-in function 'help' that invokes
1029 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
1030 it displays a message reminding the user to use 'help()' or
1031 'help(object)'.
1032
Tim Petersa814db52001-05-14 07:05:58 +00001033Tests
1034
1035- New test_mutants.py runs dict comparisons where the key and value
1036 comparison operators mutute the dicts randomly during comparison. This
1037 rapidly causes Python to crash under earlier releases (not for the faint
1038 of heart: it can also cause Win9x to freeze or reboot!).
1039
1040- New test_pprint.py verfies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +00001041 pprint.isreadable() return sensible results. Also verifies that simple
1042 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +00001043
Tim Peters4324aa32001-05-28 22:30:08 +00001044C API
1045
1046- Removed the unused last_is_sticky argument from the internal
1047 _PyTuple_Resize(). If this affects you, you were cheating.
1048
1049
Guido van Rossum55a78992001-07-17 17:22:32 +00001050======================================================================
1051
1052
Guido van Rossumffe13be2001-04-16 18:46:45 +00001053What's New in Python 2.1 (final)?
1054=================================
1055
1056We only changed a few things since the last release candidate, all in
1057Python library code:
1058
1059- A bug in the locale module was fixed that affected locales which
1060 define no grouping for numeric formatting.
1061
1062- A few bugs in the weakref module's implementations of weak
1063 dictionaries (WeakValueDictionary and WeakKeyDictionary) were fixed,
1064 and the test suite was updated to check for these bugs.
1065
1066- An old bug in the os.path.walk() function (introduced in Python
1067 2.0!) was fixed: a non-existent file would cause an exception
1068 instead of being ignored.
1069
1070- Fixed a few bugs in the new symtable module found by Neil Norwitz's
1071 PyChecker.
1072
1073
Guido van Rossum5b08f132001-04-16 02:05:23 +00001074What's New in Python 2.1c2?
1075===========================
Barry Warsaw11e89c72001-04-11 20:37:57 +00001076
Guido van Rossum5b08f132001-04-16 02:05:23 +00001077A flurry of small changes, and one showstopper fixed in the nick of
1078time made it necessary to release another release candidate. The list
1079here is the *complete* list of patches (except version updates):
Guido van Rossum4fb60362001-04-13 00:46:14 +00001080
Guido van Rossum5b08f132001-04-16 02:05:23 +00001081Core
Guido van Rossum4fb60362001-04-13 00:46:14 +00001082
Guido van Rossum5b08f132001-04-16 02:05:23 +00001083- Tim discovered a nasty bug in the dictionary code, caused by
1084 PyDict_Next() calling dict_resize(), and the GC code's use of
1085 PyDict_Next() violating an assumption in dict_items(). This was
1086 fixed with considerable amounts of band-aid, but the net effect is a
1087 saner and more robust implementation.
1088
1089- Made a bunch of symbols static that were accidentally global.
1090
1091Build and Ports
1092
1093- The setup.py script didn't check for a new enough version of zlib
1094 (1.1.3 is needed). Now it does.
1095
1096- Changed "make clean" target to also remove shared libraries.
1097
1098- Added a more general warning about the SGI Irix optimizer to README.
1099
1100Library
1101
1102- Fix a bug in urllib.basejoin("http://host", "../file.html") which
1103 omitted the slash between host and file.html.
1104
1105- The mailbox module's _Mailbox class contained a completely broken
1106 and undocumented seek() method. Ripped it out.
1107
1108- Fixed a bunch of typos in various library modules (urllib2, smtpd,
1109 sgmllib, netrc, chunk) found by Neil Norwitz's PyChecker.
1110
1111- Fixed a few last-minute bugs in unittest.
1112
1113Extensions
1114
1115- Reverted the patch to the OpenSSL code in socketmodule.c to support
1116 RAND_status() and the EGD, and the subsequent patch that tried to
1117 fix it for pre-0.9.5 versions; the problem with the patch is that on
1118 some systems it issues a warning whenever socket is imported, and
1119 that's unacceptable.
1120
1121Tests
1122
1123- Fixed the pickle tests to work with "import test.test_pickle".
1124
1125- Tweaked test_locale.py to actually run the test Windows.
1126
1127- In distutils/archive_util.py, call zipfile.ZipFile() with mode "w",
1128 not "wb" (which is not a valid mode at all).
1129
1130- Fix pstats browser crashes. Import readline if it exists to make
1131 the user interface nicer.
1132
1133- Add "import thread" to the top of test modules that import the
1134 threading module (test_asynchat and test_threadedtempfile). This
1135 prevents test failures caused by a broken threading module resulting
1136 from a previously caught failed import.
1137
1138- Changed test_asynchat.py to set the SO_REUSEADDR option; this was
1139 needed on some platforms (e.g. Solaris 8) when the tests are run
1140 twice in succession.
1141
1142- Skip rather than fail test_sunaudiodev if no audio device is found.
1143
1144
1145What's New in Python 2.1c1?
1146===========================
1147
1148This list was significantly updated when 2.1c2 was released; the 2.1c1
1149release didn't mention most changes that were actually part of 2.1c1:
1150
1151Legal
1152
1153- Copyright was assigned to the Python Software Foundation (PSF) and a
1154 PSF license (very similar to the CNRI license) was added.
1155
1156- The CNRI copyright notice was updated to include 2001.
1157
1158Core
Barry Warsaw11e89c72001-04-11 20:37:57 +00001159
Guido van Rossumc9932722001-04-12 02:31:27 +00001160- After a public outcry, assignment to __debug__ is no longer illegal;
1161 instead, a warning is issued. It will become illegal in 2.2.
1162
Guido van Rossum5b08f132001-04-16 02:05:23 +00001163- Fixed a core dump with "%#x" % 0, and changed the semantics so that
1164 "%#x" now always prepends "0x", even if the value is zero.
1165
1166- Fixed some nits in the bytecode compiler.
1167
1168- Fixed core dumps when calling certain kinds of non-functions.
1169
1170- Fixed various core dumps caused by reference count bugs.
1171
1172Build and Ports
1173
1174- Use INSTALL_SCRIPT to install script files.
1175
Guido van Rossum34d37dc2001-04-11 21:03:32 +00001176- New port: SCO Unixware 7, by Billy G. Allie.
1177
Guido van Rossum5b08f132001-04-16 02:05:23 +00001178- Updated RISCOS port.
1179
1180- Updated BeOS port and notes.
1181
1182- Various other porting problems resolved.
1183
1184Library
1185
1186- The TERMIOS and SOCKET modules are now truly obsolete and
1187 unnecessary. Their symbols are incorporated in the termios and
1188 socket modules.
1189
1190- Fixed some 64-bit bugs in pickle, cPickle, and struct, and added
1191 better tests for pickling.
1192
1193- threading: make Condition.wait() robust against KeyboardInterrupt.
1194
1195- zipfile: add support to zipfile to support opening an archive
1196 represented by an open file rather than a file name. Fix bug where
1197 the archive was not properly closed. Fixed a bug in this bugfix
1198 where flush() was called for a read-only file.
1199
1200- imputil: added an uninstall() method to the ImportManager.
1201
1202- Canvas: fixed bugs in lower() and tkraise() methods.
1203
1204- SocketServer: API change (added overridable close_request() method)
1205 so that the TCP server can explicitly close the request.
1206
1207- pstats: Eric Raymond added a simple interactive statistics browser,
1208 invoked when the module is run as a script.
1209
1210- locale: fixed a problem in format().
1211
1212- webbrowser: made it work when the BROWSER environment variable has a
1213 value like "/usr/bin/netscape". Made it auto-detect Konqueror for
1214 KDE 2. Fixed some other nits.
1215
1216- unittest: changes to allow using a different exception than
1217 AssertionError, and added a few more function aliases. Some other
1218 small changes.
1219
1220- urllib, urllib2: fixed redirect problems and a coupleof other nits.
1221
1222- asynchat: fixed a critical bug in asynchat that slipped through the
1223 2.1b2 release. Fixed another rare bug.
1224
1225- Fix some unqualified except: clauses (always a bad code example).
1226
1227XML
1228
1229- pyexpat: new API get_version_string().
1230
1231- Fixed some minidom bugs.
1232
1233Extensions
1234
1235- Fixed a core dump in _weakref. Removed the weakref.mapping()
1236 function (it adds nothing to the API).
1237
1238- Rationalized the use of header files in the readline module, to make
1239 it compile (albeit with some warnings) with the very recent readline
1240 4.2, without breaking for earlier versions.
1241
1242- Hopefully fixed a buffering problem in linuxaudiodev.
1243
1244- Attempted a fix to make the OpenSSL support in the socket module
1245 work again with pre-0.9.5 versions of OpenSSL.
1246
1247Tests
1248
1249- Added a test case for asynchat and asyncore.
1250
1251- Removed coupling between tests where one test failing could break
1252 another.
1253
1254Tools
1255
1256- Ping added an interactive help browser to pydoc, fixed some nits
1257 in the rest of the pydoc code, and added some features to his
1258 inspect module.
1259
1260- An updated python-mode.el version 4.1 which integrates Ken
1261 Manheimer's pdbtrack.el. This makes debugging Python code via pdb
1262 much nicer in XEmacs and Emacs. When stepping through your program
1263 with pdb, in either the shell window or the *Python* window, the
1264 source file and line will be tracked by an arrow. Very cool!
1265
1266- IDLE: syntax warnings in interactive mode are changed into errors.
1267
1268- Some improvements to Tools/webchecker (ignore some more URL types,
Tim Peters0e57abf2001-05-02 07:39:38 +00001269 follow some more links).
Guido van Rossum5b08f132001-04-16 02:05:23 +00001270
1271- Brought the Tools/compiler package up to date.
Guido van Rossum34d37dc2001-04-11 21:03:32 +00001272
Barry Warsaw11e89c72001-04-11 20:37:57 +00001273
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00001274What's New in Python 2.1 beta 2?
1275================================
1276
Guido van Rossum053ae352001-03-22 14:17:21 +00001277(Unlisted are many fixed bugs, more documentation, etc.)
1278
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00001279Core language, builtins, and interpreter
1280
Guido van Rossum053ae352001-03-22 14:17:21 +00001281- The nested scopes work (enabled by "from __future__ import
1282 nested_scopes") is completed; in particular, the future now extends
1283 into code executed through exec, eval() and execfile(), and into the
1284 interactive interpreter.
1285
1286- When calling a base class method (e.g. BaseClass.__init__(self)),
1287 this is now allowed even if self is not strictly spoken a class
1288 instance (e.g. when using metaclasses or the Don Beaudry hook).
1289
1290- Slice objects are now comparable but not hashable; this prevents
1291 dict[:] from being accepted but meaningless.
1292
1293- Complex division is now calculated using less braindead algorithms.
1294 This doesn't change semantics except it's more likely to give useful
1295 results in extreme cases. Complex repr() now uses full precision
1296 like float repr().
1297
1298- sgmllib.py now calls handle_decl() for simple <!...> declarations.
1299
Jeremy Hyltonf626db72001-03-23 14:18:27 +00001300- It is illegal to assign to the name __debug__, which is set when the
1301 interpreter starts. It is effectively a compile-time constant.
1302
1303- A warning will be issued if a global statement for a variable
1304 follows a use or assignment of that variable.
1305
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00001306Standard library
1307
Guido van Rossum053ae352001-03-22 14:17:21 +00001308- unittest.py, a unit testing framework by Steve Purcell (PyUNIT,
1309 inspired by JUnit), is now part of the standard library. You now
1310 have a choice of two testing frameworks: unittest requires you to
1311 write testcases as separate code, doctest gathers them from
1312 docstrings. Both approaches have their advantages and
1313 disadvantages.
1314
1315- A new module Tix was added, which wraps the Tix extension library
1316 for Tk. With that module, it is not necessary to statically link
1317 Tix with _tkinter, since Tix will be loaded with Tcl's "package
1318 require" command. See Demo/tix/.
1319
1320- tzparse.py is now obsolete.
1321
1322- In gzip.py, the seek() and tell() methods are removed -- they were
1323 non-functional anyway, and it's better if callers can test for their
1324 existence with hasattr().
1325
1326Python/C API
1327
1328- PyDict_Next(): it is now safe to call PyDict_SetItem() with a key
1329 that's already in the dictionary during a PyDict_Next() iteration.
1330 This used to fail occasionally when a dictionary resize operation
1331 could be triggered that would rehash all the keys. All other
1332 modifications to the dictionary are still off-limits during a
1333 PyDict_Next() iteration!
1334
1335- New extended APIs related to passing compiler variables around.
1336
1337- New abstract APIs PyObject_IsInstance(), PyObject_IsSubclass()
1338 implement isinstance() and issubclass().
1339
1340- Py_BuildValue() now has a "D" conversion to create a Python complex
1341 number from a Py_complex C value.
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00001342
Fred Drake4e262a92001-03-22 18:26:47 +00001343- Extensions types which support weak references must now set the
1344 field allocated for the weak reference machinery to NULL themselves;
1345 this is done to avoid the cost of checking each object for having a
1346 weakly referencable type in PyObject_INIT(), since most types are
1347 not weakly referencable.
1348
Jeremy Hyltonf626db72001-03-23 14:18:27 +00001349- PyFrame_FastToLocals() and PyFrame_LocalsToFast() copy bindings for
1350 free variables and cell variables to and from the frame's f_locals.
1351
1352- Variants of several functions defined in pythonrun.h have been added
1353 to support the nested_scopes future statement. The variants all end
1354 in Flags and take an extra argument, a PyCompilerFlags *; examples:
1355 PyRun_AnyFileExFlags(), PyRun_InteractiveLoopFlags(). These
1356 variants may be removed in Python 2.2, when nested scopes are
Tim Peters0e57abf2001-05-02 07:39:38 +00001357 mandatory.
Jeremy Hyltonf626db72001-03-23 14:18:27 +00001358
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +00001359Distutils
1360
1361- the sdist command now writes a PKG-INFO file, as described in PEP 241,
1362 into the release tree.
1363
Tim Peters0e57abf2001-05-02 07:39:38 +00001364- several enhancements to the bdist_wininst command from Thomas Heller
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +00001365 (an uninstaller, more customization of the installer's display)
1366
1367- from Jack Jansen: added Mac-specific code to generate a dialog for
1368 users to specify the command-line (because providing a command-line with
Tim Peters0e57abf2001-05-02 07:39:38 +00001369 MacPython is awkward). Jack also made various fixes for the Mac
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +00001370 and the Metrowerks compiler.
Tim Peters0e57abf2001-05-02 07:39:38 +00001371
1372- added 'platforms' and 'keywords' to the set of metadata that can be
1373 specified for a distribution.
Andrew M. Kuchling8e9972c2001-03-22 15:42:08 +00001374
1375- applied patches from Jason Tishler to make the compiler class work with
1376 Cygwin.
1377
1378
Tim Peters2fe289a2001-03-01 22:19:38 +00001379What's New in Python 2.1 beta 1?
1380================================
Tim Petersd66595f2001-02-04 03:09:53 +00001381
1382Core language, builtins, and interpreter
1383
Guido van Rossum9d0fbde2001-03-02 14:00:32 +00001384- Following an outcry from the community about the amount of code
1385 broken by the nested scopes feature introduced in 2.1a2, we decided
1386 to make this feature optional, and to wait until Python 2.2 (or at
1387 least 6 months) to make it standard. The option can be enabled on a
1388 per-module basis by adding "from __future__ import nested_scopes" at
1389 the beginning of a module (before any other statements, but after
1390 comments and an optional docstring). See PEP 236 (Back to the
1391 __future__) for a description of the __future__ statement. PEP 227
1392 (Statically Nested Scopes) has been updated to reflect this change,
1393 and to clarify the semantics in a number of endcases.
1394
1395- The nested scopes code, when enabled, has been hardened, and most
1396 bugs and memory leaks in it have been fixed.
1397
1398- Compile-time warnings are now generated for a number of conditions
1399 that will break or change in meaning when nested scopes are enabled:
1400
1401 - Using "from...import *" or "exec" without in-clause in a function
1402 scope that also defines a lambda or nested function with one or
1403 more free (non-local) variables. The presence of the import* or
1404 bare exec makes it impossible for the compiler to determine the
1405 exact set of local variables in the outer scope, which makes it
1406 impossible to determine the bindings for free variables in the
1407 inner scope. To avoid the warning about import *, change it into
1408 an import of explicitly name object, or move the import* statement
1409 to the global scope; to avoid the warning about bare exec, use
1410 exec...in... (a good idea anyway -- there's a possibility that
1411 bare exec will be deprecated in the future).
1412
1413 - Use of a global variable in a nested scope with the same name as a
1414 local variable in a surrounding scope. This will change in
1415 meaning with nested scopes: the name in the inner scope will
1416 reference the variable in the outer scope rather than the global
1417 of the same name. To avoid the warning, either rename the outer
1418 variable, or use a global statement in the inner function.
1419
Neil Schemenauera35c6882001-02-27 04:45:05 +00001420- An optional object allocator has been included. This allocator is
1421 optimized for Python objects and should be faster and use less memory
1422 than the standard system allocator. It is not enabled by default
1423 because of possible thread safety problems. The allocator is only
1424 protected by the Python interpreter lock and it is possible that some
1425 extension modules require a thread safe allocator. The object
1426 allocator can be enabled by providing the "--with-pymalloc" option to
1427 configure.
1428
Tim Petersd66595f2001-02-04 03:09:53 +00001429Standard library
1430
Martin v. Löwis2a5130e2001-02-27 04:21:58 +00001431- pyexpat now detects the expat version if expat.h defines it. A
1432 number of additional handlers are provided, which are only available
1433 since expat 1.95. In addition, the methods SetParamEntityParsing and
1434 GetInputContext of Parser objects are available with 1.95.x
1435 only. Parser objects now provide the ordered_attributes and
1436 specified_attributes attributes. A new module expat.model was added,
1437 which offers a number of additional constants if 1.95.x is used.
1438
1439- xml.dom offers the new functions registerDOMImplementation and
1440 getDOMImplementation.
1441
1442- xml.dom.minidom offers a toprettyxml method. A number of DOM
1443 conformance issues have been resolved. In particular, Element now
1444 has an hasAttributes method, and the handling of namespaces was
1445 improved.
1446
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +00001447- Ka-Ping Yee contributed two new modules: inspect.py, a module for
1448 getting information about live Python code, and pydoc.py, a module
1449 for interactively converting docstrings to HTML or text.
1450 Tools/scripts/pydoc, which is now automatically installed into
Tim Peters1eff7962001-03-01 02:31:33 +00001451 <prefix>/bin, uses pydoc.py to display documentation; try running
Guido van Rossume3955a82001-03-02 14:05:59 +00001452 "pydoc -h" for instructions. "pydoc -g" pops up a small GUI that
1453 lets you browse the module docstrings using a web browser.
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +00001454
Tim Peters1eff7962001-03-01 02:31:33 +00001455- New library module difflib.py, primarily packaging the SequenceMatcher
1456 class at the heart of the popular ndiff.py file-comparison tool.
1457
1458- doctest.py (a framework for verifying Python code examples in docstrings)
1459 is now part of the std library.
1460
Tim Petersd66595f2001-02-04 03:09:53 +00001461Windows changes
1462
Guido van Rossume3955a82001-03-02 14:05:59 +00001463- A new entry in the Start menu, "Module Docs", runs "pydoc -g" -- a
1464 small GUI that lets you browse the module docstrings using your
1465 default web browser.
1466
Tim Peters1eff7962001-03-01 02:31:33 +00001467- Import is now case-sensitive. PEP 235 (Import on Case-Insensitive
1468 Platforms) is implemented. See
1469
1470 http://python.sourceforge.net/peps/pep-0235.html
1471
1472 for full details, especially the "Current Lower-Left Semantics" section.
1473 The new Windows import rules are simpler than before:
1474
1475 A. If the PYTHONCASEOK environment variable exists, same as
1476 before: silently accept the first case-insensitive match of any
1477 kind; raise ImportError if none found.
1478
1479 B. Else search sys.path for the first case-sensitive match; raise
1480 ImportError if none found.
1481
1482 The same rules have been implented on other platforms with case-
1483 insensitive but case-preserving filesystems too (including Cygwin, and
1484 several flavors of Macintosh operating systems).
Tim Petersd66595f2001-02-04 03:09:53 +00001485
Tim Peters25a9ce32001-02-19 07:06:36 +00001486- winsound module: Under Win9x, winsound.Beep() now attempts to simulate
1487 what it's supposed to do (and does do under NT and 2000) via direct
1488 port manipulation. It's unknown whether this will work on all systems,
Tim Peters1eff7962001-03-01 02:31:33 +00001489 but it does work on my Win98SE systems now and was known to be useless on
Tim Peters25a9ce32001-02-19 07:06:36 +00001490 all Win9x systems before.
1491
Tim Peters1eff7962001-03-01 02:31:33 +00001492- Build: Subproject _test (effectively) renamed to _testcapi.
1493
Tim Peters2fe289a2001-03-01 22:19:38 +00001494New platforms
1495
1496- 2.1 should compile and run out of the box under MacOS X, even using HFS+.
1497 Thanks to Steven Majewski!
1498
1499- 2.1 should compile and run out of the box on Cygwin. Thanks to Jason
1500 Tishler!
1501
Guido van Rossum9089b272001-03-02 06:49:50 +00001502- 2.1 contains new files and patches for RISCOS, thanks to Dietmar
1503 Schwertberger! See RISCOS/README for more information -- it seems
1504 that because of the bizarre filename conventions on RISCOS, no port
Guido van Rossum49192142001-10-24 20:51:44 +00001505 to that platform is easy.
Guido van Rossum9089b272001-03-02 06:49:50 +00001506
Tim Peters25a9ce32001-02-19 07:06:36 +00001507
Tim Petersd7b5e882001-01-25 03:36:26 +00001508What's New in Python 2.1 alpha 2?
1509=================================
Tim Peters40ead762001-01-27 05:35:26 +00001510
Tim Petersd7b5e882001-01-25 03:36:26 +00001511Core language, builtins, and interpreter
1512
Jeremy Hylton4589bd82001-02-01 20:38:45 +00001513- Scopes nest. If a name is used in a function or class, but is not
1514 local, the definition in the nearest enclosing function scope will
1515 be used. One consequence of this change is that lambda statements
1516 could reference variables in the namespaces where the lambda is
1517 defined. In some unusual cases, this change will break code.
1518
1519 In all previous version of Python, names were resolved in exactly
1520 three namespaces -- the local namespace, the global namespace, and
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +00001521 the builtin namespace. According to this old definition, if a
Jeremy Hylton4589bd82001-02-01 20:38:45 +00001522 function A is defined within a function B, the names bound in B are
1523 not visible in A. The new rules make names bound in B visible in A,
1524 unless A contains a name binding that hides the binding in B.
1525
1526 Section 4.1 of the reference manual describes the new scoping rules
1527 in detail. The test script in Lib/test/test_scope.py demonstrates
1528 some of the effects of the change.
1529
1530 The new rules will cause existing code to break if it defines nested
1531 functions where an outer function has local variables with the same
1532 name as globals or builtins used by the inner function. Example:
1533
1534 def munge(str):
1535 def helper(x):
1536 return str(x)
1537 if type(str) != type(''):
1538 str = helper(str)
1539 return str.strip()
1540
1541 Under the old rules, the name str in helper() is bound to the
1542 builtin function str(). Under the new rules, it will be bound to
1543 the argument named str and an error will occur when helper() is
1544 called.
1545
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +00001546- The compiler will report a SyntaxError if "from ... import *" occurs
1547 in a function or class scope. The language reference has documented
1548 that this case is illegal, but the compiler never checked for it.
1549 The recent introduction of nested scope makes the meaning of this
1550 form of name binding ambiguous. In a future release, the compiler
1551 may allow this form when there is no possibility of ambiguity.
1552
Tim Peters40ead762001-01-27 05:35:26 +00001553- repr(string) is easier to read, now using hex escapes instead of octal,
1554 and using \t, \n and \r instead of \011, \012 and \015 (respectively):
1555
1556 >>> "\texample \r\n" + chr(0) + chr(255)
1557 '\texample \r\n\x00\xff' # in 2.1
1558 '\011example \015\012\000\377' # in 2.0
1559
Moshe Zadka6af0ce02001-01-29 06:41:00 +00001560- Functions are now compared and hashed by identity, not by value, since
1561 the func_code attribute is writable.
1562
Fred Drakefb9d7122001-02-01 20:00:40 +00001563- Weak references (PEP 205) have been added. This involves a few
1564 changes in the core, an extension module (_weakref), and a Python
1565 module (weakref). The weakref module is the public interface. It
1566 includes support for "explicit" weak references, proxy objects, and
1567 mappings with weakly held values.
1568
Jeremy Hylton0072d5a2001-02-01 22:53:15 +00001569- A 'continue' statement can now appear in a try block within the body
1570 of a loop. It is still not possible to use continue in a finally
Tim Peters9ea17ac2001-02-02 05:57:15 +00001571 clause.
Jeremy Hylton0072d5a2001-02-01 22:53:15 +00001572
Tim Petersd7b5e882001-01-25 03:36:26 +00001573Standard library
1574
Barry Warsaw30dbd142001-01-31 22:14:01 +00001575- mailbox.py now has a new class, PortableUnixMailbox which is
1576 identical to UnixMailbox but uses a more portable scheme for
1577 determining From_ separators. Also, the constructors for all the
1578 classes in this module have a new optional `factory' argument, which
1579 is a callable used when new message classes must be instantiated by
1580 the next() method.
1581
Tim Petersd7b5e882001-01-25 03:36:26 +00001582- random.py is now self-contained, and offers all the functionality of
1583 the now-deprecated whrandom.py. See the docs for details. random.py
1584 also supports new functions getstate() and setstate(), for saving
Tim Petersd52269b2001-01-25 06:23:18 +00001585 and restoring the internal state of the generator; and jumpahead(n),
1586 for quickly forcing the internal state to be the same as if n calls to
1587 random() had been made. The latter is particularly useful for multi-
1588 threaded programs, creating one instance of the random.Random() class for
1589 each thread, then using .jumpahead() to force each instance to use a
1590 non-overlapping segment of the full period.
Tim Petersd7b5e882001-01-25 03:36:26 +00001591
Tim Peters0de88fc2001-02-01 04:59:18 +00001592- random.py's seed() function is new. For bit-for-bit compatibility with
1593 prior releases, use the whseed function instead. The new seed function
1594 addresses two problems: (1) The old function couldn't produce more than
1595 about 2**24 distinct internal states; the new one about 2**45 (the best
1596 that can be done in the Wichmann-Hill generator). (2) The old function
1597 sometimes produced identical internal states when passed distinct
1598 integers, and there was no simple way to predict when that would happen;
1599 the new one guarantees to produce distinct internal states for all
1600 arguments in [0, 27814431486576L).
1601
Jeremy Hylton4c4fda02001-02-02 03:29:24 +00001602- The socket module now supports raw packets on Linux. The socket
1603 family is AF_PACKET.
1604
Tim Peters9ea17ac2001-02-02 05:57:15 +00001605- test_capi.py is a start at running tests of the Python C API. The tests
1606 are implemented by the new Modules/_testmodule.c.
1607
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +00001608- A new extension module, _symtable, provides provisional access to the
1609 internal symbol table used by the Python compiler. A higher-level
1610 interface will be added on top of _symtable in a future release.
1611
Andrew M. Kuchlingdebc3522001-02-22 15:53:21 +00001612- Removed the obsolete soundex module.
1613
Martin v. Löwis2a5130e2001-02-27 04:21:58 +00001614- xml.dom.minidom now uses the standard DOM exceptions. Node supports
1615 the isSameNode method; NamedNodeMap the get method.
1616
1617- xml.sax.expatreader supports the lexical handler property; it
1618 generates comment, startCDATA, and endCDATA events.
1619
Tim Petersee826f82001-01-31 19:39:44 +00001620Windows changes
1621
1622- Build procedure: the zlib project is built in a different way that
1623 ensures the zlib header files used can no longer get out of synch with
Tim Peters9ea17ac2001-02-02 05:57:15 +00001624 the zlib binary used. See PCbuild\readme.txt for details. Your old
1625 zlib-related directories can be deleted; you'll need to download fresh
1626 source for zlib and unpack it into a new directory.
Tim Petersee826f82001-01-31 19:39:44 +00001627
Tim Peters9ea17ac2001-02-02 05:57:15 +00001628- Build: New subproject _test for the benefit of test_capi.py (see above).
1629
Tim Petersb16c56f2001-02-02 21:24:51 +00001630- Build: New subproject _symtable, for new DLL _symtable.pyd (a nascent
1631 interface to some Python compiler internals).
1632
1633- Build: Subproject ucnhash is gone, since the code was folded into the
Tim Peters9ea17ac2001-02-02 05:57:15 +00001634 unicodedata subproject.
Tim Petersd7b5e882001-01-25 03:36:26 +00001635
Tim Petersa3a3a032000-11-30 05:22:44 +00001636What's New in Python 2.1 alpha 1?
1637=================================
1638
1639Core language, builtins, and interpreter
1640
Marc-André Lemburgebb195b2001-01-20 10:34:52 +00001641- There is a new Unicode companion to the PyObject_Str() API
1642 called PyObject_Unicode(). It behaves in the same way as the
1643 former, but assures that the returned value is an Unicode object
1644 (applying the usual coercion if necessary).
Marc-André Lemburgad7c98e2001-01-17 17:09:53 +00001645
Guido van Rossumf98eda02001-01-17 15:54:45 +00001646- The comparison operators support "rich comparison overloading" (PEP
1647 207). C extension types can provide a rich comparison function in
1648 the new tp_richcompare slot in the type object. The cmp() function
1649 and the C function PyObject_Compare() first try the new rich
1650 comparison operators before trying the old 3-way comparison. There
1651 is also a new C API PyObject_RichCompare() (which also falls back on
1652 the old 3-way comparison, but does not constrain the outcome of the
1653 rich comparison to a Boolean result).
1654
1655 The rich comparison function takes two objects (at least one of
1656 which is guaranteed to have the type that provided the function) and
1657 an integer indicating the opcode, which can be Py_LT, Py_LE, Py_EQ,
1658 Py_NE, Py_GT, Py_GE (for <, <=, ==, !=, >, >=), and returns a Python
1659 object, which may be NotImplemented (in which case the tp_compare
1660 slot function is used as a fallback, if defined).
1661
1662 Classes can overload individual comparison operators by defining one
1663 or more of the methods__lt__, __le__, __eq__, __ne__, __gt__,
Guido van Rossuma88479f2001-01-18 14:28:08 +00001664 __ge__. There are no explicit "reflected argument" versions of
1665 these; instead, __lt__ and __gt__ are each other's reflection,
1666 likewise for__le__ and __ge__; __eq__ and __ne__ are their own
1667 reflection (similar at the C level). No other implications are
1668 made; in particular, Python does not assume that == is the Boolean
1669 inverse of !=, or that < is the Boolean inverse of >=. This makes
1670 it possible to define types with partial orderings.
Guido van Rossumf98eda02001-01-17 15:54:45 +00001671
1672 Classes or types that want to implement (in)equality tests but not
1673 the ordering operators (i.e. unordered types) should implement ==
1674 and !=, and raise an error for the ordering operators.
1675
Guido van Rossuma88479f2001-01-18 14:28:08 +00001676 It is possible to define types whose rich comparison results are not
Guido van Rossumf98eda02001-01-17 15:54:45 +00001677 Boolean; e.g. a matrix type might want to return a matrix of bits
1678 for A < B, giving elementwise comparisons. Such types should ensure
1679 that any interpretation of their value in a Boolean context raises
1680 an exception, e.g. by defining __nonzero__ (or the tp_nonzero slot
1681 at the C level) to always raise an exception.
1682
Guido van Rossuma88479f2001-01-18 14:28:08 +00001683- Complex numbers use rich comparisons to define == and != but raise
1684 an exception for <, <=, > and >=. Unfortunately, this also means
1685 that cmp() of two complex numbers raises an exception when the two
1686 numbers differ. Since it is not mathematically meaningful to compare
1687 complex numbers except for equality, I hope that this doesn't break
1688 too much code.
1689
Tim Peters3389f192001-02-18 08:48:49 +00001690- The outcome of comparing non-numeric objects of different types is
Tim Peters14495852001-02-18 08:28:33 +00001691 not defined by the language, other than that it's arbitrary but
1692 consistent (see the Reference Manual). An implementation detail changed
1693 in 2.1a1 such that None now compares less than any other object. Code
1694 relying on this new behavior (like code that relied on the previous
1695 behavior) does so at its own risk.
1696
Barry Warsaw573b5412001-01-15 20:43:18 +00001697- Functions and methods now support getting and setting arbitrarily
1698 named attributes (PEP 232). Functions have a new __dict__
1699 (a.k.a. func_dict) which hold the function attributes. Methods get
1700 and set attributes on their underlying im_func. It is a TypeError
1701 to set an attribute on a bound method.
1702
Guido van Rossum051e3352001-01-15 19:11:10 +00001703- The xrange() object implementation has been improved so that
1704 xrange(sys.maxint) can be used on 64-bit platforms. There's still a
1705 limitation that in this case len(xrange(sys.maxint)) can't be
1706 calculated, but the common idiom "for i in xrange(sys.maxint)" will
1707 work fine as long as the index i doesn't actually reach 2**31.
1708 (Python uses regular ints for sequence and string indices; fixing
1709 that is much more work.)
1710
Guido van Rossum1cc8f832001-01-12 16:25:08 +00001711- Two changes to from...import:
1712
Guido van Rossumba381232001-02-03 15:06:40 +00001713 1) "from M import X" now works even if (after loading module M)
1714 sys.modules['M'] is not a real module; it's basically a getattr()
1715 operation with AttributeError exceptions changed into ImportError.
Guido van Rossum1cc8f832001-01-12 16:25:08 +00001716
1717 2) "from M import *" now looks for M.__all__ to decide which names to
1718 import; if M.__all__ doesn't exist, it uses M.__dict__.keys() but
1719 filters out names starting with '_' as before. Whether or not
1720 __all__ exists, there's no restriction on the type of M.
1721
Guido van Rossumf61f1662001-01-10 20:13:55 +00001722- File objects have a new method, xreadlines(). This is the fastest
1723 way to iterate over all lines in a file:
1724
1725 for line in file.xreadlines():
1726 ...do something to line...
1727
1728 See the xreadlines module (mentioned below) for how to do this for
1729 other file-like objects.
1730
1731- Even if you don't use file.xreadlines(), you may expect a speedup on
1732 line-by-line input. The file.readline() method has been optimized
Tim Petersf29b64d2001-01-15 06:33:19 +00001733 quite a bit in platform-specific ways: on systems (like Linux) that
1734 support flockfile(), getc_unlocked(), and funlockfile(), those are
1735 used by default. On systems (like Windows) without getc_unlocked(),
1736 a complicated (but still thread-safe) method using fgets() is used by
1737 default.
1738
Tim Petersd52269b2001-01-25 06:23:18 +00001739 You can force use of the fgets() method by #define'ing
1740 USE_FGETS_IN_GETLINE at build time (it may be faster than
Tim Petersf29b64d2001-01-15 06:33:19 +00001741 getc_unlocked()).
1742
Tim Petersd52269b2001-01-25 06:23:18 +00001743 You can force fgets() not to be used by #define'ing
1744 DONT_USE_FGETS_IN_GETLINE (this is the first thing to try if std test
Tim Petersf29b64d2001-01-15 06:33:19 +00001745 test_bufio.py fails -- and let us know if it does!).
1746
1747- In addition, the fileinput module, while still slower than the other
1748 methods on most platforms, has been sped up too, by using
1749 file.readlines(sizehint).
Guido van Rossumf61f1662001-01-10 20:13:55 +00001750
1751- Support for run-time warnings has been added, including a new
1752 command line option (-W) to specify the disposition of warnings.
1753 See the description of the warnings module below.
1754
1755- Extensive changes have been made to the coercion code. This mostly
1756 affects extension modules (which can now implement mixed-type
1757 numerical operators without having to use coercion), but
1758 occasionally, in boundary cases the coercion semantics have changed
1759 subtly. Since this was a terrible gray area of the language, this
Guido van Rossumae72d872001-01-11 15:00:14 +00001760 is considered an improvement. Also note that __rcmp__ is no longer
Guido van Rossumf61f1662001-01-10 20:13:55 +00001761 supported -- instead of calling __rcmp__, __cmp__ is called with
Guido van Rossuma88479f2001-01-18 14:28:08 +00001762 reflected arguments.
Guido van Rossumf61f1662001-01-10 20:13:55 +00001763
Guido van Rossumf98eda02001-01-17 15:54:45 +00001764- In connection with the coercion changes, a new built-in singleton
1765 object, NotImplemented is defined. This can be returned for
1766 operations that wish to indicate they are not implemented for a
1767 particular combination of arguments. From C, this is
1768 Py_NotImplemented.
1769
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +00001770- The interpreter accepts now bytecode files on the command line even
1771 if they do not have a .pyc or .pyo extension. On Linux, after executing
1772
Martin v. Löwise214baa2001-02-04 22:37:56 +00001773import imp,sys,string
1774magic = string.join(["\\x%.2x" % ord(c) for c in imp.get_magic()],"")
1775reg = ':pyc:M::%s::%s:' % (magic, sys.executable)
1776open("/proc/sys/fs/binfmt_misc/register","wb").write(reg)
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +00001777
1778 any byte code file can be used as an executable (i.e. as an argument
1779 to execve(2)).
1780
Tim Peters9940b802000-12-01 07:59:35 +00001781- %[xXo] formats of negative Python longs now produce a sign
Tim Petersa3a3a032000-11-30 05:22:44 +00001782 character. In 1.6 and earlier, they never produced a sign,
1783 and raised an error if the value of the long was too large
1784 to fit in a Python int. In 2.0, they produced a sign if and
1785 only if too large to fit in an int. This was inconsistent
1786 across platforms (because the size of an int varies across
1787 platforms), and inconsistent with hex() and oct(). Example:
1788
1789 >>> "%x" % -0x42L
Tim Peters9940b802000-12-01 07:59:35 +00001790 '-42' # in 2.1
Tim Petersa3a3a032000-11-30 05:22:44 +00001791 'ffffffbe' # in 2.0 and before, on 32-bit machines
1792 >>> hex(-0x42L)
1793 '-0x42L' # in all versions of Python
1794
Tim Peters9940b802000-12-01 07:59:35 +00001795 The behavior of %d formats for negative Python longs remains
1796 the same as in 2.0 (although in 1.6 and before, they raised
1797 an error if the long didn't fit in a Python int).
1798
1799 %u formats don't make sense for Python longs, but are allowed
1800 and treated the same as %d in 2.1. In 2.0, a negative long
1801 formatted via %u produced a sign if and only if too large to
1802 fit in an int. In 1.6 and earlier, a negative long formatted
1803 via %u raised an error if it was too big to fit in an int.
1804
Guido van Rossum3661d392000-12-12 22:10:31 +00001805- Dictionary objects have an odd new method, popitem(). This removes
1806 an arbitrary item from the dictionary and returns it (in the form of
1807 a (key, value) pair). This can be useful for algorithms that use a
1808 dictionary as a bag of "to do" items and repeatedly need to pick one
1809 item. Such algorithms normally end up running in quadratic time;
1810 using popitem() they can usually be made to run in linear time.
1811
Tim Peters36cdad12000-12-29 02:06:45 +00001812Standard library
1813
Thomas Woutersfe385252001-01-19 23:16:56 +00001814- In the time module, the time argument to the functions strftime,
1815 localtime, gmtime, asctime and ctime is now optional, defaulting to
1816 the current time (in the local timezone).
1817
Guido van Rossumda91f222001-01-15 16:36:08 +00001818- The ftplib module now defaults to passive mode, which is deemed a
1819 more useful default given that clients are often inside firewalls
1820 these days. Note that this could break if ftplib is used to connect
1821 to a *server* that is inside a firewall, from outside; this is
1822 expected to be a very rare situation. To fix that, you can call
1823 ftp.set_pasv(0).
1824
Martin v. Löwis10a27872001-01-13 09:54:41 +00001825- The module site now treats .pth files not only for path configuration,
1826 but also supports extensions to the initialization code: Lines starting
1827 with import are executed.
1828
Guido van Rossumf61f1662001-01-10 20:13:55 +00001829- There's a new module, warnings, which implements a mechanism for
1830 issuing and filtering warnings. There are some new built-in
1831 exceptions that serve as warning categories, and a new command line
1832 option, -W, to control warnings (e.g. -Wi ignores all warnings, -We
1833 turns warnings into errors). warnings.warn(message[, category])
1834 issues a warning message; this can also be called from C as
1835 PyErr_Warn(category, message).
1836
1837- A new module xreadlines was added. This exports a single factory
1838 function, xreadlines(). The intention is that this code is the
1839 absolutely fastest way to iterate over all lines in an open
1840 file(-like) object:
1841
1842 import xreadlines
1843 for line in xreadlines.xreadlines(file):
1844 ...do something to line...
1845
1846 This is equivalent to the previous the speed record holder using
1847 file.readlines(sizehint). Note that if file is a real file object
1848 (as opposed to a file-like object), this is equivalent:
1849
1850 for line in file.xreadlines():
1851 ...do something to line...
1852
Tim Peters36cdad12000-12-29 02:06:45 +00001853- The bisect module has new functions bisect_left, insort_left,
1854 bisect_right and insort_right. The old names bisect and insort
1855 are now aliases for bisect_right and insort_right. XXX_right
1856 and XXX_left methods differ in what happens when the new element
1857 compares equal to one or more elements already in the list: the
1858 XXX_left methods insert to the left, the XXX_right methods to the
Tim Peters742bb6f2001-01-05 08:05:32 +00001859 right. Code that doesn't care where equal elements end up should
1860 continue to use the old, short names ("bisect" and "insort").
Tim Peters36cdad12000-12-29 02:06:45 +00001861
Andrew M. Kuchlingf6f3a892001-01-13 14:53:34 +00001862- The new curses.panel module wraps the panel library that forms part
1863 of SYSV curses and ncurses. Contributed by Thomas Gellekum.
1864
Guido van Rossumf61f1662001-01-10 20:13:55 +00001865- The SocketServer module now sets the allow_reuse_address flag by
1866 default in the TCPServer class.
1867
1868- A new function, sys._getframe(), returns the stack frame pointer of
1869 the caller. This is intended only as a building block for
1870 higher-level mechanisms such as string interpolation.
1871
Martin v. Löwis2a5130e2001-02-27 04:21:58 +00001872- The pyexpat module supports a number of new handlers, which are
1873 available only in expat 1.2. If invocation of a callback fails, it
1874 will report an additional frame in the traceback. Parser objects
1875 participate now in garbage collection. If expat reports an unknown
1876 encoding, pyexpat will try to use a Python codec; that works only
1877 for single-byte charsets. The parser type objects is exposed as
1878 XMLParserObject.
1879
1880- xml.dom now offers standard definitions for symbolic node type and
1881 exception code constants, and a hierarchy of DOM exceptions. minidom
1882 was adjusted to use them.
1883
1884- The conformance of xml.dom.minidom to the DOM specification was
1885 improved. It detects a number of additional error cases; the
1886 previous/next relationship works even when the tree is modified;
1887 Node supports the normalize() method; NamedNodeMap, DocumentType and
1888 DOMImplementation classes were added; Element supports the
1889 hasAttribute and hasAttributeNS methods; and Text supports the splitText
1890 method.
1891
Guido van Rossumf61f1662001-01-10 20:13:55 +00001892Build issues
1893
Guido van Rossum1e33bdc2001-01-23 03:17:00 +00001894- For Unix (and Unix-compatible) builds, configuration and building of
1895 extension modules is now greatly automated. Rather than having to
1896 edit the Modules/Setup file to indicate which modules should be
1897 built and where their include files and libraries are, a
1898 distutils-based setup.py script now takes care of building most
1899 extension modules. All extension modules built this way are built
1900 as shared libraries. Only a few modules that must be linked
1901 statically are still listed in the Setup file; you won't need to
1902 edit their configuration.
1903
1904- Python should now build out of the box on Cygwin. If it doesn't,
1905 mail to Jason Tishler (jlt63 at users.sourceforge.net).
Guido van Rossumf61f1662001-01-10 20:13:55 +00001906
1907- Python now always uses its own (renamed) implementation of getopt()
1908 -- there's too much variation among C library getopt()
1909 implementations.
1910
1911- C++ compilers are better supported; the CXX macro is always set to a
1912 C++ compiler if one is found.
Tim Peters36cdad12000-12-29 02:06:45 +00001913
Tim Petersd92dfe02000-12-12 01:18:41 +00001914Windows changes
1915
1916- select module: By default under Windows, a select() call
1917 can specify no more than 64 sockets. Python now boosts
1918 this Microsoft default to 512. If you need even more than
1919 that, see the MS docs (you'll need to #define FD_SETSIZE
1920 and recompile Python from source).
1921
Guido van Rossumf61f1662001-01-10 20:13:55 +00001922- Support for Windows 3.1, DOS and OS/2 is gone. The Lib/dos-8x3
1923 subdirectory is no more!
1924
Tim Petersa3a3a032000-11-30 05:22:44 +00001925
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001926What's New in Python 2.0?
Fred Drake1a640502000-10-16 20:27:25 +00001927=========================
Guido van Rossum61000331997-08-15 04:39:58 +00001928
Guido van Rossum8ed602b2000-09-01 22:34:33 +00001929Below is a list of all relevant changes since release 1.6. Older
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001930changes are in the file HISTORY. If you are making the jump directly
1931from Python 1.5.2 to 2.0, make sure to read the section for 1.6 in the
1932HISTORY file! Many important changes listed there.
Guido van Rossum61000331997-08-15 04:39:58 +00001933
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001934Alternatively, a good overview of the changes between 1.5.2 and 2.0 is
1935the document "What's New in Python 2.0" by Kuchling and Moshe Zadka:
1936http://starship.python.net/crew/amk/python/writing/new-python/.
Guido van Rossum1f83cce1997-10-06 21:04:35 +00001937
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001938--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)
Guido van Rossum437cfe81999-04-08 20:17:57 +00001939
1940======================================================================
1941
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001942What's new in 2.0 (since release candidate 1)?
1943==============================================
1944
1945Standard library
1946
1947- The copy_reg module was modified to clarify its intended use: to
1948 register pickle support for extension types, not for classes.
1949 pickle() will raise a TypeError if it is passed a class.
1950
1951- Fixed a bug in gettext's "normalize and expand" code that prevented
1952 it from finding an existing .mo file.
1953
1954- Restored support for HTTP/0.9 servers in httplib.
1955
Tim Peters989b7b92000-10-16 20:24:53 +00001956- The math module was changed to stop raising OverflowError in case of
1957 underflow, and return 0 instead in underflow cases. Whether Python
1958 used to raise OverflowError in case of underflow was platform-
1959 dependent (it did when the platform math library set errno to ERANGE
1960 on underflow).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001961
1962- Fixed a bug in StringIO that occurred when the file position was not
1963 at the end of the file and write() was called with enough data to
1964 extend past the end of the file.
1965
1966- Fixed a bug that caused Tkinter error messages to get lost on
1967 Windows. The bug was fixed by replacing direct use of
1968 interp->result with Tcl_GetStringResult(interp).
1969
1970- Fixed bug in urllib2 that caused it to fail when it received an HTTP
1971 redirect response.
1972
1973- Several changes were made to distutils: Some debugging code was
1974 removed from util. Fixed the installer used when an external zip
1975 program (like WinZip) is not found; the source code for this
1976 installer is in Misc/distutils. check_lib() was modified to behave
1977 more like AC_CHECK_LIB by add other_libraries() as a parameter. The
1978 test for whether installed modules are on sys.path was changed to
1979 use both normcase() and normpath().
1980
Jeremy Hyltond867a2c2000-10-16 20:41:38 +00001981- Several minor bugs were fixed in the xml package (the minidom,
1982 pulldom, expatreader, and saxutils modules).
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001983
1984- The regression test driver (regrtest.py) behavior when invoked with
1985 -l changed: It now reports a count of objects that are recognized as
1986 garbage but not freed by the garbage collector.
1987
Tim Peters989b7b92000-10-16 20:24:53 +00001988- The regression test for the math module was changed to test
1989 exceptional behavior when the test is run in verbose mode. Python
1990 cannot yet guarantee consistent exception behavior across platforms,
1991 so the exception part of test_math is run only in verbose mode, and
1992 may fail on your platform.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00001993
1994Internals
1995
1996- PyOS_CheckStack() has been disabled on Win64, where it caused
1997 test_sre to fail.
1998
1999Build issues
2000
2001- Changed compiler flags, so that gcc is always invoked with -Wall and
2002 -Wstrict-prototypes. Users compiling Python with GCC should see
2003 exactly one warning, except if they have passed configure the
Tim Peters989b7b92000-10-16 20:24:53 +00002004 --with-pydebug flag. The expected warning is for getopt() in
Tim Petersadfb94f2000-10-16 20:51:33 +00002005 Modules/main.c. This warning will be fixed for Python 2.1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002006
Tim Petersa3a3a032000-11-30 05:22:44 +00002007- Fixed configure to add -threads argument during linking on OSF1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002008
2009Tools and other miscellany
2010
2011- The compiler in Tools/compiler was updated to support the new
2012 language features introduced in 2.0: extended print statement, list
2013 comprehensions, and augmented assignments. The new compiler should
2014 also be backwards compatible with Python 1.5.2; the compiler will
2015 always generate code for the version of the interpreter it runs
Tim Petersa3a3a032000-11-30 05:22:44 +00002016 under.
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002017
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002018What's new in 2.0 release candidate 1 (since beta 2)?
2019=====================================================
2020
Jeremy Hylton6040aaa2000-10-09 21:27:22 +00002021What is release candidate 1?
2022
2023We believe that release candidate 1 will fix all known bugs that we
2024intend to fix for the 2.0 final release. This release should be a bit
2025more stable than the previous betas. We would like to see even more
2026widespread testing before the final release, so we are producing this
2027release candidate. The final release will be exactly the same unless
2028any show-stopping (or brown bag) bugs are found by testers of the
2029release candidate.
2030
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002031All the changes since the last beta release are bug fixes or changes
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002032to support building Python for specific platforms.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002033
2034Core language, builtins, and interpreter
2035
2036- A bug that caused crashes when __coerce__ was used with augmented
2037 assignment, e.g. +=, was fixed.
2038
2039- Raise ZeroDivisionError when raising zero to a negative number,
2040 e.g. 0.0 ** -2.0. Note that math.pow is unrelated to the builtin
2041 power operator and the result of math.pow(0.0, -2.0) will vary by
2042 platform. On Linux, it raises a ValueError.
2043
2044- A bug in Unicode string interpolation was fixed that occasionally
2045 caused errors with formats including "%%". For example, the
2046 following expression "%% %s" % u"abc" no longer raises a TypeError.
2047
2048- Compilation of deeply nested expressions raises MemoryError instead
2049 of SyntaxError, e.g. eval("[" * 50 + "]" * 50).
2050
2051- In 2.0b2 on Windows, the interpreter wrote .pyc files in text mode,
2052 rendering them useless. They are now written in binary mode again.
2053
2054Standard library
2055
2056- Keyword arguments are now accepted for most pattern and match object
2057 methods in SRE, the standard regular expression engine.
2058
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002059- In SRE, fixed error with negative lookahead and lookbehind that
Jeremy Hylton32e20ff2000-10-09 19:48:11 +00002060 manifested itself as a runtime error in patterns like "(?<!abc)(def)".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002061
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002062- Several bugs in the Unicode handling and error handling in _tkinter
2063 were fixed.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002064
2065- Fix memory management errors in Merge() and Tkapp_Call() routines.
2066
2067- Several changes were made to cStringIO to make it compatible with
2068 the file-like object interface and with StringIO. If operations are
2069 performed on a closed object, an exception is raised. The truncate
2070 method now accepts a position argument and readline accepts a size
Tim Petersa3a3a032000-11-30 05:22:44 +00002071 argument.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002072
2073- There were many changes made to the linuxaudiodev module and its
2074 test suite; as a result, a short, unexpected audio sample should now
Tim Petersa3a3a032000-11-30 05:22:44 +00002075 play when the regression test is run.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002076
2077 Note that this module is named poorly, because it should work
2078 correctly on any platform that supports the Open Sound System
Tim Petersa3a3a032000-11-30 05:22:44 +00002079 (OSS).
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002080
2081 The module now raises exceptions when errors occur instead of
2082 crashing. It also defines the AFMT_A_LAW format (logarithmic A-law
2083 audio) and defines a getptr() method that calls the
2084 SNDCTL_DSP_GETxPTR ioctl defined in the OSS Programmer's Guide.
2085
2086- The library_version attribute, introduced in an earlier beta, was
2087 removed because it can not be supported with early versions of the C
2088 readline library, which provides no way to determine the version at
2089 compile-time.
2090
2091- The binascii module is now enabled on Win64.
2092
Tim Peters46446d62000-10-09 21:19:31 +00002093- tokenize.py no longer suffers "recursion depth" errors when parsing
2094 programs with very long string literals.
2095
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002096Internals
2097
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002098- Fixed several buffer overflow vulnerabilities in calculate_path(),
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002099 which is called when the interpreter starts up to determine where
2100 the standard library is installed. These vulnerabilities affect all
2101 previous versions of Python and can be exploited by setting very
2102 long values for PYTHONHOME or argv[0]. The risk is greatest for a
2103 setuid Python script, although use of the wrapper in
2104 Misc/setuid-prog.c will eliminate the vulnerability.
2105
2106- Fixed garbage collection bugs in instance creation that were
2107 triggered when errors occurred during initialization. The solution,
2108 applied in cPickle and in PyInstance_New(), is to call
2109 PyObject_GC_Init() after the initialization of the object's
2110 container attributes is complete.
2111
2112- pyexpat adds definitions of PyModule_AddStringConstant and
2113 PyModule_AddObject if the Python version is less than 2.0, which
2114 provides compatibility with PyXML on Python 1.5.2.
2115
2116- If the platform has a bogus definition for LONG_BIT (the number of
2117 bits in a long), an error will be reported at compile time.
2118
2119- Fix bugs in _PyTuple_Resize() which caused hard-to-interpret garbage
2120 collection crashes and possibly other, unreported crashes.
2121
2122- Fixed a memory leak in _PyUnicode_Fini().
2123
2124Build issues
2125
2126- configure now accepts a --with-suffix option that specifies the
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002127 executable suffix. This is useful for builds on Cygwin and Mac OS
Tim Petersa3a3a032000-11-30 05:22:44 +00002128 X, for example.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002129
2130- The mmap.PAGESIZE constant is now initialized using sysconf when
2131 possible, which eliminates a dependency on -lucb for Reliant UNIX.
2132
2133- The md5 file should now compile on all platforms.
2134
2135- The select module now compiles on platforms that do not define
2136 POLLRDNORM and related constants.
2137
2138- Darwin (Mac OS X): Initial support for static builds on this
Tim Petersa3a3a032000-11-30 05:22:44 +00002139 platform.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002140
Jeremy Hylton10921202000-10-09 18:34:12 +00002141- BeOS: A number of changes were made to the build and installation
2142 process. ar-fake now operates on a directory of object files.
2143 dl_export.h is gone, and its macros now appear on the mwcc command
2144 line during build on PPC BeOS.
2145
Jeremy Hyltond6e20232000-10-16 20:08:38 +00002146- Platform directory in lib/python2.0 is "plat-beos5" (or
Jeremy Hylton10921202000-10-09 18:34:12 +00002147 "plat-beos4", if building on BeOS 4.5), rather than "plat-beos".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +00002148
2149- Cygwin: Support for shared libraries, Tkinter, and sockets.
2150
2151- SunOS 4.1.4_JL: Fix test for directory existence in configure.
2152
2153Tools and other miscellany
2154
2155- Removed debugging prints from main used with freeze.
2156
Tim Peters46446d62000-10-09 21:19:31 +00002157- IDLE auto-indent no longer crashes when it encounters Unicode
2158 characters.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002159
2160What's new in 2.0 beta 2 (since beta 1)?
2161========================================
2162
2163Core language, builtins, and interpreter
2164
Tim Peters482c0212000-09-26 06:33:09 +00002165- Add support for unbounded ints in %d,i,u,x,X,o formats; for example
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002166 "%d" % 2L**64 == "18446744073709551616".
Jeremy Hylton1b618592000-09-26 05:32:36 +00002167
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002168- Add -h and -V command line options to print the usage message and
2169 Python version number and exit immediately.
2170
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002171- eval() and exec accept Unicode objects as code parameters.
2172
2173- getattr() and setattr() now also accept Unicode objects for the
2174 attribute name, which are converted to strings using the default
2175 encoding before lookup.
2176
2177- Multiplication on string and Unicode now does proper bounds
2178 checking; e.g. 'a' * 65536 * 65536 will raise ValueError, "repeated
2179 string is too long."
2180
2181- Better error message when continue is found in try statement in a
Tim Petersa3a3a032000-11-30 05:22:44 +00002182 loop.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002183
Jeremy Hylton1b618592000-09-26 05:32:36 +00002184
2185Standard library and extensions
2186
Guido van Rossum5b08f132001-04-16 02:05:23 +00002187- socket module: the OpenSSL code now adds support for RAND_status()
2188 and EGD (Entropy Gathering Device).
2189
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002190- array: reverse() method of array now works. buffer_info() now does
Jeremy Hylton1b618592000-09-26 05:32:36 +00002191 argument checking; it still takes no arguments.
2192
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002193- asyncore/asynchat: Included most recent version from Sam Rushing.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002194
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002195- cgi: Accept '&' or ';' as separator characters when parsing form data.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002196
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002197- CGIHTTPServer: Now works on Windows (and perhaps even Mac).
Jeremy Hylton1b618592000-09-26 05:32:36 +00002198
2199- ConfigParser: When reading the file, options spelled in upper case
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002200 letters are now correctly converted to lowercase.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002201
2202- copy: Copy Unicode objects atomically.
2203
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002204- cPickle: Fail gracefully when copy_reg can't be imported.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002205
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002206- cStringIO: Implemented readlines() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002207
Fred Drake67233bc2000-09-26 16:40:27 +00002208- dbm: Add get() and setdefault() methods to dbm object. Add constant
2209 `library' to module that names the library used. Added doc strings
2210 and method names to error messages. Uses configure to determine
2211 which ndbm.h file to include; Berkeley DB's nbdm and GDBM's ndbm is
2212 now available options.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002213
2214- distutils: Update to version 0.9.3.
2215
2216- dl: Add several dl.RTLD_ constants.
2217
2218- fpectl: Now supported on FreeBSD.
2219
2220- gc: Add DEBUG_SAVEALL option. When enabled all garbage objects
2221 found by the collector will be saved in gc.garbage. This is useful
2222 for debugging a program that creates reference cycles.
2223
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002224- httplib: Three changes: Restore support for set_debuglevel feature
Jeremy Hylton1b618592000-09-26 05:32:36 +00002225 of HTTP class. Do not close socket on zero-length response. Do not
2226 crash when server sends invalid content-length header.
2227
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002228- mailbox: Mailbox class conforms better to qmail specifications.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002229
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002230- marshal: When reading a short, sign-extend on platforms where shorts
2231 are bigger than 16 bits. When reading a long, repair the unportable
2232 sign extension that was being done for 64-bit machines. (It assumed
2233 that signed right shift sign-extends.)
2234
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002235- operator: Add contains(), invert(), __invert__() as aliases for
2236 __contains__(), inv(), and __inv__() respectively.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002237
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002238- os: Add support for popen2() and popen3() on all platforms where
2239 fork() exists. (popen4() is still in the works.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00002240
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002241- os: (Windows only:) Add startfile() function that acts like double-
Tim Peters482c0212000-09-26 06:33:09 +00002242 clicking on a file in Explorer (or passing the file name to the
2243 DOS "start" command).
Jeremy Hylton1b618592000-09-26 05:32:36 +00002244
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002245- os.path: (Windows, DOS:) Treat trailing colon correctly in
Tim Peters482c0212000-09-26 06:33:09 +00002246 os.path.join. os.path.join("a:", "b") yields "a:b".
Jeremy Hylton1b618592000-09-26 05:32:36 +00002247
2248- pickle: Now raises ValueError when an invalid pickle that contains
2249 a non-string repr where a string repr was expected. This behavior
2250 matches cPickle.
2251
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002252- posixfile: Remove broken __del__() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002253
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002254- py_compile: support CR+LF line terminators in source file.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002255
2256- readline: Does not immediately exit when ^C is hit when readline and
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002257 threads are configured. Adds definition of rl_library_version. (The
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002258 latter addition requires GNU readline 2.2 or later.)
Jeremy Hylton1b618592000-09-26 05:32:36 +00002259
2260- rfc822: Domain literals returned by AddrlistClass method
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002261 getdomainliteral() are now properly wrapped in brackets.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002262
2263- site: sys.setdefaultencoding() should only be called in case the
Tim Peters482c0212000-09-26 06:33:09 +00002264 standard default encoding ("ascii") is changed. This saves quite a
Jeremy Hylton1b618592000-09-26 05:32:36 +00002265 few cycles during startup since the first call to
2266 setdefaultencoding() will initialize the codec registry and the
2267 encodings package.
2268
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002269- socket: Support for size hint in readlines() method of object returned
2270 by makefile().
Jeremy Hylton1b618592000-09-26 05:32:36 +00002271
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002272- sre: Added experimental expand() method to match objects. Does not
Jeremy Hylton625915e2000-10-02 13:43:33 +00002273 use buffer interface on Unicode strings. Does not hang if group id
Jeremy Hylton1b618592000-09-26 05:32:36 +00002274 is followed by whitespace.
2275
Tim Petersa3a3a032000-11-30 05:22:44 +00002276- StringIO: Size hint in readlines() is now supported as documented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002277
2278- struct: Check ranges for bytes and shorts.
2279
2280- urllib: Improved handling of win32 proxy settings. Fixed quote and
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002281 quote_plus functions so that the always encode a comma.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002282
2283- Tkinter: Image objects are now guaranteed to have unique ids. Set
2284 event.delta to zero if Tk version doesn't support mousewheel.
2285 Removed some debugging prints.
2286
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002287- UserList: now implements __contains__().
Jeremy Hylton1b618592000-09-26 05:32:36 +00002288
Fred Drake67233bc2000-09-26 16:40:27 +00002289- webbrowser: On Windows, use os.startfile() instead of os.popen(),
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002290 which works around a bug in Norton AntiVirus 2000 that leads directly
2291 to a Blue Screen freeze.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002292
2293- xml: New version detection code allows PyXML to override standard
2294 XML package if PyXML version is greater than 0.6.1.
2295
Fred Drake64bb3802000-09-26 16:21:35 +00002296- xml.dom: DOM level 1 support for basic XML. Includes xml.dom.minidom
2297 (conventional DOM), and xml.dom.pulldom, which allows building the DOM
2298 tree only for nodes which are sufficiently interesting to a specific
2299 application. Does not provide the HTML-specific extensions. Still
2300 undocumented.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002301
Fred Drake64bb3802000-09-26 16:21:35 +00002302- xml.sax: SAX 2 support for Python, including all the handler
2303 interfaces needed to process XML 1.0 compliant XML. Some
2304 documentation is already available.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002305
Fred Drake64bb3802000-09-26 16:21:35 +00002306- pyexpat: Renamed to xml.parsers.expat since this is part of the new,
2307 packagized XML support.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002308
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002309
Jeremy Hylton1b618592000-09-26 05:32:36 +00002310C API
2311
2312- Add three new convenience functions for module initialization --
2313 PyModule_AddObject(), PyModule_AddIntConstant(), and
2314 PyModule_AddStringConstant().
2315
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002316- Cleaned up definition of NULL in C source code; all definitions were
Jeremy Hylton1b618592000-09-26 05:32:36 +00002317 removed and add #error to Python.h if NULL isn't defined after
2318 #include of stdio.h.
2319
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002320- Py_PROTO() macros that were removed in 2.0b1 have been restored for
Jeremy Hylton1b618592000-09-26 05:32:36 +00002321 backwards compatibility (at the source level) with old extensions.
2322
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002323- A wrapper API was added for signal() and sigaction(). Instead of
2324 either function, always use PyOS_getsig() to get a signal handler
2325 and PyOS_setsig() to set one. A new convenience typedef
2326 PyOS_sighandler_t is defined for the type of signal handlers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002327
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002328- Add PyString_AsStringAndSize() function that provides access to the
Jeremy Hylton1b618592000-09-26 05:32:36 +00002329 internal data buffer and size of a string object -- or the default
2330 encoded version of a Unicode object.
2331
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002332- PyString_Size() and PyString_AsString() accept Unicode objects.
2333
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002334- The standard header <limits.h> is now included by Python.h (if it
Fred Drake64bb3802000-09-26 16:21:35 +00002335 exists). INT_MAX and LONG_MAX will always be defined, even if
2336 <limits.h> is not available.
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002337
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002338- PyFloat_FromString takes a second argument, pend, that was
2339 effectively useless. It is now officially useless but preserved for
2340 backwards compatibility. If the pend argument is not NULL, *pend is
2341 set to NULL.
2342
2343- PyObject_GetAttr() and PyObject_SetAttr() now accept Unicode objects
2344 for the attribute name. See note on getattr() above.
2345
2346- A few bug fixes to argument processing for Unicode.
2347 PyArg_ParseTupleAndKeywords() now accepts "es#" and "es".
2348 PyArg_Parse() special cases "s#" for Unicode objects; it returns a
2349 pointer to the default encoded string data instead of to the raw
Tim Petersa3a3a032000-11-30 05:22:44 +00002350 UTF-16.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002351
2352- Py_BuildValue accepts B format (for bgen-generated code).
2353
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002354
Jeremy Hylton1b618592000-09-26 05:32:36 +00002355Internals
2356
2357- On Unix, fix code for finding Python installation directory so that
2358 it works when argv[0] is a relative path.
2359
Andrew M. Kuchlinga1099be2000-12-15 01:16:43 +00002360- Added a true unicode_internal_encode() function and fixed the
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002361 unicode_internal_decode function() to support Unicode objects directly
Jeremy Hylton1b618592000-09-26 05:32:36 +00002362 rather than by generating a copy of the object.
2363
Tim Peters482c0212000-09-26 06:33:09 +00002364- Several of the internal Unicode tables are much smaller now, and
2365 the source code should be much friendlier to weaker compilers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002366
Jeremy Hylton97693b02000-09-26 17:42:51 +00002367- In the garbage collector: Fixed bug in collection of tuples. Fixed
2368 bug that caused some instances to be removed from the container set
2369 while they were still live. Fixed parsing in gc.set_debug() for
2370 platforms where sizeof(long) > sizeof(int).
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002371
2372- Fixed refcount problem in instance deallocation that only occurred
2373 when Py_REF_DEBUG was defined and Py_TRACE_REFS was not.
2374
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002375- On Windows, getpythonregpath is now protected against null data in
2376 registry key.
2377
2378- On Unix, create .pyc/.pyo files with O_EXCL flag to avoid a race
Tim Petersa3a3a032000-11-30 05:22:44 +00002379 condition.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002380
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002381
Jeremy Hylton1b618592000-09-26 05:32:36 +00002382Build and platform-specific issues
2383
2384- Better support of GNU Pth via --with-pth configure option.
2385
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002386- Python/C API now properly exposed to dynamically-loaded extension
2387 modules on Reliant UNIX.
Jeremy Hylton1b618592000-09-26 05:32:36 +00002388
2389- Changes for the benefit of SunOS 4.1.4 (really!). mmapmodule.c:
2390 Don't define MS_SYNC to be zero when it is undefined. Added missing
2391 prototypes in posixmodule.c.
2392
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002393- Improved support for HP-UX build. Threads should now be correctly
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002394 configured (on HP-UX 10.20 and 11.00).
Jeremy Hylton1b618592000-09-26 05:32:36 +00002395
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002396- Fix largefile support on older NetBSD systems and OpenBSD by adding
2397 define for TELL64.
2398
2399
2400Tools and other miscellany
2401
2402- ftpmirror: Call to main() is wrapped in if __name__ == "__main__".
2403
2404- freeze: The modulefinder now works with 2.0 opcodes.
2405
Tim Petersa3a3a032000-11-30 05:22:44 +00002406- IDLE:
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00002407 Move hackery of sys.argv until after the Tk instance has been
2408 created, which allows the application-specific Tkinter
2409 initialization to be executed if present; also pass an explicit
2410 className parameter to the Tk() constructor.
Fred Drake64bb3802000-09-26 16:21:35 +00002411
Jeremy Hylton1b618592000-09-26 05:32:36 +00002412
2413What's new in 2.0 beta 1?
2414=========================
2415
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002416Source Incompatibilities
2417------------------------
2418
2419None. Note that 1.6 introduced several incompatibilities with 1.5.2,
2420such as single-argument append(), connect() and bind(), and changes to
2421str(long) and repr(float).
2422
2423
2424Binary Incompatibilities
2425------------------------
2426
2427- Third party extensions built for Python 1.5.x or 1.6 cannot be used
2428with Python 2.0; these extensions will have to be rebuilt for Python
24292.0.
2430
2431- On Windows, attempting to import a third party extension built for
2432Python 1.5.x or 1.6 results in an immediate crash; there's not much we
2433can do about this. Check your PYTHONPATH environment variable!
2434
2435- Python bytecode files (*.pyc and *.pyo) are not compatible between
2436releases.
2437
2438
2439Overview of Changes Since 1.6
2440-----------------------------
2441
2442There are many new modules (including brand new XML support through
2443the xml package, and i18n support through the gettext module); a list
2444of all new modules is included below. Lots of bugs have been fixed.
2445
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002446The process for making major new changes to the language has changed
2447since Python 1.6. Enhancements must now be documented by a Python
2448Enhancement Proposal (PEP) before they can be accepted.
2449
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002450There are several important syntax enhancements, described in more
2451detail below:
2452
2453 - Augmented assignment, e.g. x += 1
2454
2455 - List comprehensions, e.g. [x**2 for x in range(10)]
2456
2457 - Extended import statement, e.g. import Module as Name
2458
2459 - Extended print statement, e.g. print >> file, "Hello"
2460
2461Other important changes:
2462
2463 - Optional collection of cyclical garbage
2464
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002465Python Enhancement Proposal (PEP)
2466---------------------------------
2467
2468PEP stands for Python Enhancement Proposal. A PEP is a design
2469document providing information to the Python community, or describing
2470a new feature for Python. The PEP should provide a concise technical
2471specification of the feature and a rationale for the feature.
2472
2473We intend PEPs to be the primary mechanisms for proposing new
2474features, for collecting community input on an issue, and for
2475documenting the design decisions that have gone into Python. The PEP
2476author is responsible for building consensus within the community and
2477documenting dissenting opinions.
2478
2479The PEPs are available at http://python.sourceforge.net/peps/.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002480
2481Augmented Assignment
2482--------------------
2483
2484This must have been the most-requested feature of the past years!
2485Eleven new assignment operators were added:
2486
Guido van Rossume905e952000-09-05 12:42:46 +00002487 += -= *= /= %= **= <<= >>= &= ^= |=
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002488
2489For example,
2490
2491 A += B
2492
2493is similar to
2494
2495 A = A + B
2496
2497except that A is evaluated only once (relevant when A is something
2498like dict[index].attr).
2499
2500However, if A is a mutable object, A may be modified in place. Thus,
2501if A is a number or a string, A += B has the same effect as A = A+B
2502(except A is only evaluated once); but if a is a list, A += B has the
2503same effect as A.extend(B)!
2504
2505Classes and built-in object types can override the new operators in
2506order to implement the in-place behavior; the not-in-place behavior is
2507used automatically as a fallback when an object doesn't implement the
2508in-place behavior. For classes, the method name is derived from the
2509method name for the corresponding not-in-place operator by inserting
2510an 'i' in front of the name, e.g. __iadd__ implements in-place
2511__add__.
2512
2513Augmented assignment was implemented by Thomas Wouters.
2514
2515
2516List Comprehensions
2517-------------------
2518
2519This is a flexible new notation for lists whose elements are computed
2520from another list (or lists). The simplest form is:
2521
2522 [<expression> for <variable> in <sequence>]
2523
Guido van Rossum56db0952000-09-06 23:34:25 +00002524For example, [i**2 for i in range(4)] yields the list [0, 1, 4, 9].
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002525This is more efficient than a for loop with a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002526
2527You can also add a condition:
2528
2529 [<expression> for <variable> in <sequence> if <condition>]
2530
2531For example, [w for w in words if w == w.lower()] would yield the list
2532of words that contain no uppercase characters. This is more efficient
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002533than a for loop with an if statement and a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002534
2535You can also have nested for loops and more than one 'if' clause. For
2536example, here's a function that flattens a sequence of sequences::
2537
2538 def flatten(seq):
2539 return [x for subseq in seq for x in subseq]
2540
2541 flatten([[0], [1,2,3], [4,5], [6,7,8,9], []])
2542
2543This prints
2544
2545 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
2546
2547List comprehensions originated as a patch set from Greg Ewing; Skip
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002548Montanaro and Thomas Wouters also contributed. Described by PEP 202.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002549
2550
2551Extended Import Statement
2552-------------------------
2553
2554Many people have asked for a way to import a module under a different
2555name. This can be accomplished like this:
2556
2557 import foo
2558 bar = foo
2559 del foo
2560
2561but this common idiom gets old quickly. A simple extension of the
2562import statement now allows this to be written as follows:
2563
2564 import foo as bar
2565
2566There's also a variant for 'from ... import':
2567
2568 from foo import bar as spam
2569
2570This also works with packages; e.g. you can write this:
2571
2572 import test.regrtest as regrtest
2573
2574Note that 'as' is not a new keyword -- it is recognized only in this
2575context (this is only possible because the syntax for the import
2576statement doesn't involve expressions).
2577
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002578Implemented by Thomas Wouters. Described by PEP 221.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002579
2580
2581Extended Print Statement
2582------------------------
2583
2584Easily the most controversial new feature, this extension to the print
2585statement adds an option to make the output go to a different file
2586than the default sys.stdout.
2587
2588For example, to write an error message to sys.stderr, you can now
2589write:
2590
2591 print >> sys.stderr, "Error: bad dog!"
2592
2593As a special feature, if the expression used to indicate the file
Fred Drake45888ff2000-09-29 17:09:11 +00002594evaluates to None, the current value of sys.stdout is used. Thus:
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002595
2596 print >> None, "Hello world"
2597
2598is equivalent to
2599
2600 print "Hello world"
2601
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002602Design and implementation by Barry Warsaw. Described by PEP 214.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002603
2604
2605Optional Collection of Cyclical Garbage
2606---------------------------------------
2607
2608Python is now equipped with a garbage collector that can hunt down
2609cyclical references between Python objects. It's no replacement for
2610reference counting; in fact, it depends on the reference counts being
2611correct, and decides that a set of objects belong to a cycle if all
2612their reference counts can be accounted for from their references to
2613each other. This devious scheme was first proposed by Eric Tiedemann,
2614and brought to implementation by Neil Schemenauer.
2615
2616There's a module "gc" that lets you control some parameters of the
2617garbage collection. There's also an option to the configure script
2618that lets you enable or disable the garbage collection. In 2.0b1,
2619it's on by default, so that we (hopefully) can collect decent user
2620experience with this new feature. There are some questions about its
Fred Drake9f11cf82000-09-29 17:54:40 +00002621performance. If it proves to be too much of a problem, we'll turn it
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002622off by default in the final 2.0 release.
2623
2624
2625Smaller Changes
2626---------------
2627
2628A new function zip() was added. zip(seq1, seq2, ...) is equivalent to
2629map(None, seq1, seq2, ...) when the sequences have the same length;
2630i.e. zip([1,2,3], [10,20,30]) returns [(1,10), (2,20), (3,30)]. When
2631the lists are not all the same length, the shortest list wins:
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002632zip([1,2,3], [10,20]) returns [(1,10), (2,20)]. See PEP 201.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002633
2634sys.version_info is a tuple (major, minor, micro, level, serial).
2635
2636Dictionaries have an odd new method, setdefault(key, default).
2637dict.setdefault(key, default) returns dict[key] if it exists; if not,
2638it sets dict[key] to default and returns that value. Thus:
2639
2640 dict.setdefault(key, []).append(item)
2641
2642does the same work as this common idiom:
2643
2644 if not dict.has_key(key):
2645 dict[key] = []
2646 dict[key].append(item)
2647
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002648There are two new variants of SyntaxError that are raised for
2649indentation-related errors: IndentationError and TabError.
2650
2651Changed \x to consume exactly two hex digits; see PEP 223. Added \U
2652escape that consumes exactly eight hex digits.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002653
2654The limits on the size of expressions and file in Python source code
2655have been raised from 2**16 to 2**32. Previous versions of Python
2656were limited because the maximum argument size the Python VM accepted
2657was 2**16. This limited the size of object constructor expressions,
2658e.g. [1,2,3] or {'a':1, 'b':2}, and the size of source files. This
2659limit was raised thanks to a patch by Charles Waldman that effectively
2660fixes the problem. It is now much more likely that you will be
2661limited by available memory than by an arbitrary limit in Python.
2662
2663The interpreter's maximum recursion depth can be modified by Python
2664programs using sys.getrecursionlimit and sys.setrecursionlimit. This
2665limit is the maximum number of recursive calls that can be made by
2666Python code. The limit exists to prevent infinite recursion from
2667overflowing the C stack and causing a core dump. The default value is
26681000. The maximum safe value for a particular platform can be found
2669by running Misc/find_recursionlimit.py.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002670
2671New Modules and Packages
2672------------------------
2673
2674atexit - for registering functions to be called when Python exits.
2675
2676imputil - Greg Stein's alternative API for writing custom import
2677hooks.
2678
2679pyexpat - an interface to the Expat XML parser, contributed by Paul
2680Prescod.
2681
2682xml - a new package with XML support code organized (so far) in three
2683subpackages: xml.dom, xml.sax, and xml.parsers. Describing these
2684would fill a volume. There's a special feature whereby a
2685user-installed package named _xmlplus overrides the standard
2686xmlpackage; this is intended to give the XML SIG a hook to distribute
2687backwards-compatible updates to the standard xml package.
2688
2689webbrowser - a platform-independent API to launch a web browser.
2690
2691
Guido van Rossume905e952000-09-05 12:42:46 +00002692Changed Modules
2693---------------
2694
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002695array -- new methods for array objects: count, extend, index, pop, and
2696remove
2697
2698binascii -- new functions b2a_hex and a2b_hex that convert between
2699binary data and its hex representation
2700
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002701calendar -- Many new functions that support features including control
2702over which day of the week is the first day, returning strings instead
2703of printing them. Also new symbolic constants for days of week,
2704e.g. MONDAY, ..., SUNDAY.
2705
2706cgi -- FieldStorage objects have a getvalue method that works like a
2707dictionary's get method and returns the value attribute of the object.
2708
2709ConfigParser -- The parser object has new methods has_option,
2710remove_section, remove_option, set, and write. They allow the module
2711to be used for writing config files as well as reading them.
2712
2713ftplib -- ntransfercmd(), transfercmd(), and retrbinary() all now
Guido van Rossume905e952000-09-05 12:42:46 +00002714optionally support the RFC 959 REST command.
2715
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002716gzip -- readline and readlines now accept optional size arguments
Guido van Rossume905e952000-09-05 12:42:46 +00002717
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002718httplib -- New interfaces and support for HTTP/1.1 by Greg Stein. See
2719the module doc strings for details.
Guido van Rossum830ca2a2000-09-05 15:34:16 +00002720
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002721locale -- implement getdefaultlocale for Win32 and Macintosh
2722
2723marshal -- no longer dumps core when marshaling deeply nested or
2724recursive data structures
2725
2726os -- new functions isatty, seteuid, setegid, setreuid, setregid
2727
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002728os/popen2 -- popen2/popen3/popen4 support under Windows. popen2/popen3
2729support under Unix.
2730
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002731os/pty -- support for openpty and forkpty
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002732
2733os.path -- fix semantics of os.path.commonprefix
2734
2735smtplib -- support for sending very long messages
2736
2737socket -- new function getfqdn()
2738
2739readline -- new functions to read, write and truncate history files.
2740The readline section of the library reference manual contains an
2741example.
2742
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002743select -- add interface to poll system call
2744
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002745shutil -- new copyfileobj function
2746
2747SimpleHTTPServer, CGIHTTPServer -- Fix problems with buffering in the
2748HTTP server.
2749
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002750Tkinter -- optimization of function flatten
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002751
2752urllib -- scans environment variables for proxy configuration,
Tim Peters8b092332000-09-05 20:15:25 +00002753e.g. http_proxy.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002754
2755whichdb -- recognizes dumbdbm format
Guido van Rossume905e952000-09-05 12:42:46 +00002756
2757
2758Obsolete Modules
2759----------------
2760
2761None. However note that 1.6 made a whole slew of modules obsolete:
2762stdwin, soundex, cml, cmpcache, dircache, dump, find, grep, packmail,
2763poly, zmod, strop, util, whatsound.
2764
2765
2766Changed, New, Obsolete Tools
2767----------------------------
2768
Tim Peters8b092332000-09-05 20:15:25 +00002769None.
Guido van Rossume905e952000-09-05 12:42:46 +00002770
2771
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002772C-level Changes
2773---------------
2774
2775Several cleanup jobs were carried out throughout the source code.
2776
2777All C code was converted to ANSI C; we got rid of all uses of the
2778Py_PROTO() macro, which makes the header files a lot more readable.
2779
2780Most of the portability hacks were moved to a new header file,
2781pyport.h; several other new header files were added and some old
2782header files were removed, in an attempt to create a more rational set
2783of header files. (Few of these ever need to be included explicitly;
2784they are all included by Python.h.)
2785
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002786Trent Mick ensured portability to 64-bit platforms, under both Linux
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002787and Win64, especially for the new Intel Itanium processor. Mick also
2788added large file support for Linux64 and Win64.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00002789
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002790The C APIs to return an object's size have been update to consistently
2791use the form PyXXX_Size, e.g. PySequence_Size and PyDict_Size. In
2792previous versions, the abstract interfaces used PyXXX_Length and the
2793concrete interfaces used PyXXX_Size. The old names,
2794e.g. PyObject_Length, are still available for backwards compatibility
2795at the API level, but are deprecated.
2796
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002797The PyOS_CheckStack function has been implemented on Windows by
2798Fredrik Lundh. It prevents Python from failing with a stack overflow
2799on Windows.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002800
2801The GC changes resulted in creation of two new slots on object,
2802tp_traverse and tp_clear. The augmented assignment changes result in
Guido van Rossum4338a282000-09-06 13:02:08 +00002803the creation of a new slot for each in-place operator.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002804
2805The GC API creates new requirements for container types implemented in
Guido van Rossum4338a282000-09-06 13:02:08 +00002806C extension modules. See Include/objimpl.h for details.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002807
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002808PyErr_Format has been updated to automatically calculate the size of
2809the buffer needed to hold the formatted result string. This change
2810prevents crashes caused by programmer error.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00002811
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002812New C API calls: PyObject_AsFileDescriptor, PyErr_WriteUnraisable.
Guido van Rossume905e952000-09-05 12:42:46 +00002813
Jeremy Hylton24c3d602000-09-05 19:36:26 +00002814PyRun_AnyFileEx, PyRun_SimpleFileEx, PyRun_FileEx -- New functions
2815that are the same as their non-Ex counterparts except they take an
2816extra flag argument that tells them to close the file when done.
2817
2818XXX There were other API changes that should be fleshed out here.
Guido van Rossumab9d6f01998-08-10 22:01:13 +00002819
Tim Peters8b092332000-09-05 20:15:25 +00002820
2821Windows Changes
2822---------------
2823
2824New popen2/popen3/peopen4 in os module (see Changed Modules above).
2825
2826os.popen is much more usable on Windows 95 and 98. See Microsoft
2827Knowledge Base article Q150956. The Win9x workaround described there
2828is implemented by the new w9xpopen.exe helper in the root of your
2829Python installation. Note that Python uses this internally; it is not
2830a standalone program.
2831
2832Administrator privileges are no longer required to install Python
2833on Windows NT or Windows 2000. If you have administrator privileges,
2834Python's registry info will be written under HKEY_LOCAL_MACHINE.
2835Otherwise the installer backs off to writing Python's registry info
Guido van Rossum4338a282000-09-06 13:02:08 +00002836under HKEY_CURRENT_USER. The latter is sufficient for all "normal"
Tim Peters8b092332000-09-05 20:15:25 +00002837uses of Python, but will prevent some advanced uses from working
2838(for example, running a Python script as an NT service, or possibly
2839from CGI).
2840
2841[This was new in 1.6] The installer no longer runs a separate Tcl/Tk
2842installer; instead, it installs the needed Tcl/Tk files directly in the
2843Python directory. If you already have a Tcl/Tk installation, this
2844wastes some disk space (about 4 Megs) but avoids problems with
2845conflicting Tcl/Tk installations, and makes it much easier for Python
2846to ensure that Tcl/Tk can find all its files.
2847
2848[This was new in 1.6] The Windows installer now installs by default in
2849\Python20\ on the default volume, instead of \Program Files\Python-2.0\.
2850
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00002851
2852Updates to the changes between 1.5.2 and 1.6
2853--------------------------------------------
2854
2855The 1.6 NEWS file can't be changed after the release is done, so here
2856is some late-breaking news:
2857
2858New APIs in locale.py: normalize(), getdefaultlocale(), resetlocale(),
2859and changes to getlocale() and setlocale().
2860
2861The new module is now enabled per default.
2862
2863It is not true that the encodings codecs cannot be used for normal
2864strings: the string.encode() (which is also present on 8-bit strings
2865!) allows using them for 8-bit strings too, e.g. to convert files from
2866cp1252 (Windows) to latin-1 or vice-versa.
2867
2868Japanese codecs are available from Tamito KAJIYAMA:
2869http://pseudo.grad.sccs.chukyo-u.ac.jp/~kajiyama/python/
2870
2871
Guido van Rossumab9d6f01998-08-10 22:01:13 +00002872======================================================================