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Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001+++++++++++
2Python News
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Skip Montanaro4a385832002-09-20 17:08:52 +00005(editors: check NEWS.help for information about editing NEWS using ReST.)
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Tim Petersaf8446f2001-12-21 21:36:50 +00007What's New in Python 2.3 alpha 1?
Tim Petersaf8446f2001-12-21 21:36:50 +00008=================================
9
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +000010*XXX Release date: DD-MMM-2002 XXX*
11
Tim Petersaf8446f2001-12-21 21:36:50 +000012Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +000013--------------------------------------------
Guido van Rossum8b1e74b2002-11-23 16:28:12 +000014
Michael W. Hudson96bc3b42002-11-26 14:48:23 +000015- One can now assign to __bases__ and __name__ of new-style classes.
16
Guido van Rossum8b1e74b2002-11-23 16:28:12 +000017- dict() now accepts keyword arguments so that dict(one=1, two=2)
18 is the equivalent of {"one": 1, "two": 2}. Accordingly,
Just van Rossuma797d812002-11-23 09:45:04 +000019 the existing (but undocumented) 'items' keyword argument has
Guido van Rossum8b1e74b2002-11-23 16:28:12 +000020 been eliminated. This means that dict(items=someMapping) now has
Just van Rossuma797d812002-11-23 09:45:04 +000021 a different meaning than before.
22
Walter Dörwaldf1715402002-11-19 20:49:15 +000023- int() now returns a long object if the argument is outside the
24 integer range, so int("4"*1000), int(1e200) and int(1L<<1000) will
25 all return long objects instead of raising an OverflowError.
Tim Petersaf8446f2001-12-21 21:36:50 +000026
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +000027- Assignment to __class__ is disallowed if either the old or the new
Guido van Rossume3438782002-08-12 03:42:03 +000028 class is a statically allocated type object (such as defined by an
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +000029 extension module). This prevents anomalies like 2.__class__ = bool.
Guido van Rossume3438782002-08-12 03:42:03 +000030
31- New-style object creation and deallocation have been sped up
32 significantly; they are now faster than classic instance creation
33 and deallocation.
34
35- The __slots__ variable can now mention "private" names, and the
36 right thing will happen (e.g. __slots__ = ["__foo"]).
37
38- The built-ins slice() and buffer() are now callable types. The
39 types classobj (formerly class), code, function, instance, and
40 instancemethod (formerly instance-method), which have no built-in
41 names but are accessible through the types module, are now also
42 callable. The type dict-proxy is renamed to dictproxy.
43
44- Cycles going through the __class__ link of a new-style instance are
45 now detected by the garbage collector.
46
47- Classes using __slots__ are now properly garbage collected.
48 [SF bug 519621]
49
50- Tightened the __slots__ rules: a slot name must be a valid Python
51 identifier.
52
53- The constructor for the module type now requires a name argument and
54 takes an optional docstring argument. Previously, this constructor
55 ignored its arguments. As a consequence, deriving a class from a
56 module (not from the module type) is now illegal; previously this
57 created an unnamed module, just like invoking the module type did.
58 [SF bug 563060]
59
60- A new type object, 'basestring', is added. This is a common base type
61 for 'str' and 'unicode', and can be used instead of
62 types.StringTypes, e.g. to test whether something is "a string":
63 isinstance(x, basestring) is True for Unicode and 8-bit strings. This
64 is an abstract base class and cannot be instantiated directly.
65
66- Changed new-style class instantiation so that when C's __new__
67 method returns something that's not a C instance, its __init__ is
68 not called. [SF bug #537450]
69
70- Fixed super() to work correctly with class methods. [SF bug #535444]
71
72- If you try to pickle an instance of a class that has __slots__ but
73 doesn't define or override __getstate__, a TypeError is now raised.
74 This is done by adding a bozo __getstate__ to the class that always
75 raises TypeError. (Before, this would appear to be pickled, but the
76 state of the slots would be lost.)
77
Tim Petersaf8446f2001-12-21 21:36:50 +000078Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +000079-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +000080
Guido van Rossuma3b89532002-12-30 22:59:32 +000081- Import from zipfiles is now supported. The name of a zipfile placed
82 on sys.path causes the import statement to look for importable
83 Python modules (with .py, pyc and .pyo extensions) and packages
84 inside the zipfile. To support this, several new variables have
85 been added to the sys module: sys.meta_path, sys.path_hooks, and
86 sys.path_importer_cache; these make extending the import statement
87 much more convenient than overriding the __import__ built-in
88 function. For a description of these, see PEP 302. The zipfile
89 import follows the specification (though not the sample
90 implementation) of PEP 273. The semantics of __path__ are
91 compatible with those that have been implemented in Jython since
92 Jython 2.1.
93
Michael W. Hudsoncfd38842002-12-17 16:15:34 +000094- A frame object's f_lineno attribute can now be written to from a
95 trace function to change which line will execute next. A command to
96 exploit this from pdb has been added. [SF patch #643835]
97
Marc-André Lemburg20b91352002-12-12 18:01:43 +000098- The _codecs support module for codecs.py was turned into a builtin
99 module to assure that at least the builtin codecs are available
100 to the Python parser for source code decoding according to PEP 263.
101
Walter Dörwaldd9a6ad32002-12-12 16:41:44 +0000102- issubclass now supports a tuple as the second argument, just like
103 isinstance does. ``issubclass(X, (A, B))`` is equivalent to
104 ``issubclass(X, A) or issubclass(X, B)``.
105
Tim Petersb9099c32002-11-12 22:08:10 +0000106- Thanks to Armin Rigo, the last known way to provoke a system crash
107 by cleverly arranging for a comparison function to mutate a list
108 during a list.sort() operation has been fixed. The effect of
109 attempting to mutate a list, or even to inspect its contents or
110 length, while a sort is in progress, is not defined by the language.
111 The C implementation of Python 2.3 attempts to detect mutations,
112 and raise ValueError if one occurs, but there's no guarantee that
113 all mutations will be caught, or that any will be caught across
114 releases or implementations.
115
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000116- Unicode file name processing for Windows (PEP 277) is implemented.
Mark Hammond8696ebc2002-10-08 02:44:31 +0000117 All platforms now have an os.path.supports_unicode_filenames attribute,
118 which is set to True on Windows NT/2000/XP, and False elsewhere.
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000119
Walter Dörwald3aeb6322002-09-02 13:14:32 +0000120- Codec error handling callbacks (PEP 293) are implemented.
121 Error handling in unicode.encode or str.decode can now be customized.
122
Guido van Rossum45ec02a2002-08-19 21:43:18 +0000123- A subtle change to the semantics of the built-in function intern():
124 interned strings are no longer immortal. You must keep a reference
125 to the return value intern() around to get the benefit.
126
Guido van Rossumf808b892002-08-16 03:38:10 +0000127- Use of 'None' as a variable, argument or attribute name now
128 issues a SyntaxWarning. In the future, None may become a keyword.
129
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000130- SET_LINENO is gone. co_lnotab is now consulted to determine when to
131 call the trace function. C code that accessed f_lineno should call
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000132 PyCode_Addr2Line instead (f_lineno is still there, but only kept up
133 to date when there is a trace function set).
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000134
Guido van Rossum9be89462002-08-14 16:11:30 +0000135- There's a new warning category, FutureWarning. This is used to warn
136 about a number of situations where the value or sign of an integer
137 result will change in Python 2.4 as a result of PEP 237 (integer
138 unification). The warnings implement stage B0 mentioned in that
139 PEP. The warnings are about the following situations:
140
141 - Octal and hex literals without 'L' prefix in the inclusive range
142 [0x80000000..0xffffffff]; these are currently negative ints, but
143 in Python 2.4 they will be positive longs with the same bit
144 pattern.
145
146 - Left shifts on integer values that cause the outcome to lose
147 bits or have a different sign than the left operand. To be
148 precise: x<<n where this currently doesn't yield the same value
149 as long(x)<<n; in Python 2.4, the outcome will be long(x)<<n.
150
151 - Conversions from ints to string that show negative values as
152 unsigned ints in the inclusive range [0x80000000..0xffffffff];
153 this affects the functions hex() and oct(), and the string
154 formatting codes %u, %o, %x, and %X. In Python 2.4, these will
155 show signed values (e.g. hex(-1) currently returns "0xffffffff";
156 in Python 2.4 it will return "-0x1").
157
Guido van Rossum9a2eda52002-12-31 02:12:42 +0000158- The bits manipulated under the cover by sys.setcheckinterval() have
159 been changed. Both the check interval and the ticker used to be
160 per-thread values. They are now just a pair of global variables.
161 In addition, the default check interval was boosted from 10 to 100
162 bytecode instructions. This may have some effect on systems that
163 relied on the old default value. In particular, in multi-threaded
164 applications which try to be highly responsive, response time will
165 increase by some (perhaps imperceptible) amount.
Skip Montanaro979c74b2002-09-03 21:25:14 +0000166
Tim Petersd64c1de2002-08-12 17:36:03 +0000167- When multiplying very large integers, a version of the so-called
168 Karatsuba algorithm is now used. This is most effective if the
169 inputs have roughly the same size. If they both have about N digits,
170 Karatsuba multiplication has O(N**1.58) runtime (the exponent is
171 log_base_2(3)) instead of the previous O(N**2). Measured results may
Tim Peters012c0a32002-08-16 03:40:07 +0000172 be better or worse than that, depending on platform quirks. Besides
173 the O() improvement in raw instruction count, the Karatsuba algorithm
174 appears to have much better cache behavior on extremely large integers
175 (starting in the ballpark of a million bits). Note that this is a
176 simple implementation, and there's no intent here to compete with,
177 e.g., GMP. It gives a very nice speedup when it applies, but a package
178 devoted to fast large-integer arithmetic should run circles around it.
Tim Peters5af4e6c2002-08-12 02:31:19 +0000179
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000180- u'%c' will now raise a ValueError in case the argument is an
181 integer outside the valid range of Unicode code point ordinals.
182
Guido van Rossumdeb09362002-08-09 17:16:30 +0000183- The tempfile module has been overhauled for enhanced security. The
184 mktemp() function is now deprecated; new, safe replacements are
185 mkstemp() (for files) and mkdtemp() (for directories), and the
186 higher-level functions NamedTemporaryFile() and TemporaryFile().
187 Use of some global variables in this module is also deprecated; the
188 new functions have keyword arguments to provide the same
189 functionality. All Lib, Tools and Demo modules that used the unsafe
190 interfaces have been updated to use the safe replacements. Thanks
191 to Zack Weinberg!
192
Guido van Rossumd81a9832002-08-09 15:57:34 +0000193- When x is an object whose class implements __mul__ and __rmul__,
194 1.0*x would correctly invoke __rmul__, but 1*x would erroneously
195 invoke __mul__. This was due to the sequence-repeat code in the int
196 type. This has been fixed now.
197
Barry Warsawd79f6832002-08-06 17:01:51 +0000198- Previously, "str1 in str2" required str1 to be a string of length 1.
199 This restriction has been relaxed to allow str1 to be a string of
200 any length. Thus "'el' in 'hello world'" returns True now.
201
Guido van Rossumb57089c2002-08-06 16:20:26 +0000202- File objects are now their own iterators. For a file f, iter(f) now
203 returns f (unless f is closed), and f.next() is similar to
204 f.readline() when EOF is not reached; however, f.next() uses a
205 readahead buffer that messes up the file position, so mixing
206 f.next() and f.readline() (or other methods) doesn't work right.
207 Calling f.seek() drops the readahead buffer, but other operations
208 don't. It so happens that this gives a nice additional speed boost
209 to "for line in file:"; the xreadlines method and corresponding
Guido van Rossumbffb2ef2002-08-09 17:17:07 +0000210 module are now obsolete. Thanks to Oren Tirosh!
Guido van Rossumb57089c2002-08-06 16:20:26 +0000211
Guido van Rossumde392d32002-08-05 14:17:20 +0000212- Encoding declarations (PEP 263, phase 1) have been implemented. A
213 comment of the form "# -*- coding: <encodingname> -*-" in the first
214 or second line of a Python source file indicates the encoding.
Martin v. Löwis00f1e3f2002-08-04 17:29:52 +0000215
Tim Petersf47630f2002-08-01 02:34:51 +0000216- list.sort() has a new implementation. While cross-platform results
217 may vary, and in data-dependent ways, this is much faster on many
218 kinds of partially ordered lists than the previous implementation,
219 and reported to be just as fast on randomly ordered lists on
220 several major platforms. This sort is also stable (if A==B and A
221 precedes B in the list at the start, A precedes B after the sort too),
222 although the language definition does not guarantee stability. A
223 potential drawback is that list.sort() may require temp space of
Skip Montanaroa2a07bc2002-09-30 15:23:01 +0000224 len(list)*2 bytes (``*4`` on a 64-bit machine). It's therefore possible
Tim Petersf47630f2002-08-01 02:34:51 +0000225 for list.sort() to raise MemoryError now, even if a comparison function
226 does not. See <http://www.python.org/sf/587076> for full details.
227
Guido van Rossum2d5389c2002-07-23 03:44:35 +0000228- All standard iterators now ensure that, once StopIteration has been
229 raised, all future calls to next() on the same iterator will also
230 raise StopIteration. There used to be various counterexamples to
231 this behavior, which could caused confusion or subtle program
232 breakage, without any benefits. (Note that this is still an
233 iterator's responsibility; the iterator framework does not enforce
234 this.)
235
Mark Hammondc0e35152002-07-16 01:32:30 +0000236- Ctrl+C handling on Windows has been made more consistent with
237 other platforms. KeyboardInterrupt can now reliably be caught,
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000238 and Ctrl+C at an interactive prompt no longer terminates the
Mark Hammondc0e35152002-07-16 01:32:30 +0000239 process under NT/2k/XP (it never did under Win9x). Ctrl+C will
Tim Peters5af4e6c2002-08-12 02:31:19 +0000240 interrupt time.sleep() in the main thread, and any child processes
241 created via the popen family (on win2k; we can't make win9x work
Mark Hammond8f3afc72002-08-10 06:26:31 +0000242 reliably) are also interrupted (as generally happens on for Linux/Unix.)
243 [SF bugs 231273, 439992 and 581232]
Mark Hammondc0e35152002-07-16 01:32:30 +0000244
Mark Hammond8696ebc2002-10-08 02:44:31 +0000245- sys.getwindowsversion() has been added on Windows. This
246 returns a tuple with information about the version of Windows
247 currently running.
248
Raymond Hettinger5a04aec2002-06-25 00:25:30 +0000249- Slices and repetitions of buffer objects now consistently return
250 a string. Formerly, strings would be returned most of the time,
251 but a buffer object would be returned when the repetition count
252 was one or when the slice range was all inclusive.
253
Walter Dörwald3430d702002-06-17 10:43:59 +0000254- Unicode objects in sys.path are no longer ignored but treated
255 as directory names.
256
Neal Norwitz1f68fc72002-06-14 00:50:42 +0000257- Fixed string.startswith and string.endswith builtin methods
258 so they accept negative indices. [SF bug 493951]
259
Guido van Rossumc5fe5eb2002-06-12 03:45:21 +0000260- Fixed a bug with a continue inside a try block and a yield in the
261 finally clause. [SF bug 567538]
262
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000263- Most builtin sequences now support "extended slices", i.e. slices
Guido van Rossum2e82e712002-06-13 11:41:07 +0000264 with a third "stride" parameter. For example, "hello world"[::-1]
265 gives "dlrow olleh".
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000266
Neal Norwitzd68f5172002-05-29 15:54:55 +0000267- A new warning PendingDeprecationWarning was added to provide
268 direction on features which are in the process of being deprecated.
269 The warning will not be printed by default. To see the pending
270 deprecations, use -Walways::PendingDeprecationWarning::
271 as a command line option or warnings.filterwarnings() in code.
272
Fred Draked0ba6362002-05-02 21:28:26 +0000273- Deprecated features of xrange objects have been removed as
274 promised. The start, stop, and step attributes and the tolist()
275 method no longer exist. xrange repetition and slicing have been
276 removed.
277
Guido van Rossum7dab2422002-04-26 19:40:56 +0000278- New builtin function enumerate(x), from PEP 279. Example:
279 enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
280 The argument can be an arbitrary iterable object.
281
Neil Schemenauer89e3ee02002-04-26 01:58:53 +0000282- The assert statement no longer tests __debug__ at runtime. This means
283 that assert statements cannot be disabled by assigning a false value
284 to __debug__.
285
Walter Dörwald068325e2002-04-15 13:36:47 +0000286- A method zfill() was added to str and unicode, that fills a numeric
287 string to the left with zeros. For example,
288 "+123".zfill(6) -> "+00123".
289
Guido van Rossum862fe3c2002-04-15 12:36:47 +0000290- Complex numbers supported divmod() and the // and % operators, but
291 these make no sense. Since this was documented, they're being
292 deprecated now.
293
Guido van Rossum26dd8302002-04-26 20:11:29 +0000294- String and unicode methods lstrip(), rstrip() and strip() now take
295 an optional argument that specifies the characters to strip. For
296 example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
Guido van Rossum49042042002-04-13 00:59:05 +0000297
Guido van Rossumc0d3f4e2002-11-27 13:10:40 +0000298- There's a new dictionary constructor (a class method of the dict
299 class), dict.fromkeys(iterable, value=None). It constructs a
300 dictionary with keys taken from the iterable and all values set to a
301 single value. It can be used for building sets and for removing
302 duplicates from sequences.
Raymond Hettingere33d3df2002-11-27 07:29:33 +0000303
Guido van Rossumc69343b2002-04-12 19:22:48 +0000304- Added a new dict method pop(key). This removes and returns the
305 value corresponding to key. [SF patch #539949]
306
Guido van Rossum47834462002-04-04 15:21:33 +0000307- A new built-in type, bool, has been added, as well as built-in
308 names for its two values, True and False. Comparisons and sundry
309 other operations that return a truth value have been changed to
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000310 return a bool instead. Read PEP 285 for an explanation of why this
Guido van Rossum47834462002-04-04 15:21:33 +0000311 is backward compatible.
312
Guido van Rossum95b62a62002-03-29 01:07:24 +0000313- Fixed two bugs reported as SF #535905: under certain conditions,
314 deallocating a deeply nested structure could cause a segfault in the
315 garbage collector, due to interaction with the "trashcan" code;
316 access to the current frame during destruction of a local variable
317 could access a pointer to freed memory.
318
Guido van Rossumfe0ca4a2002-06-18 21:20:13 +0000319- The optional object allocator ("pymalloc") has been enabled by
320 default. The recommended practice for memory allocation and
321 deallocation has been streamlined. A header file is included,
322 Misc/pymemcompat.h, which can be bundled with 3rd party extensions
323 and lets them use the same API with Python versions from 1.5.2
324 onwards.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000325
Martin v. Löwiscfeb3b62002-03-03 21:30:27 +0000326- PyErr_Display will provide file and line information for all exceptions
327 that have an attribute print_file_and_line, not just SyntaxErrors.
328
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000329- The UTF-8 codec will now encode and decode Unicode surrogates
330 correctly and without raising exceptions for unpaired ones.
331
Guido van Rossumadd88062002-08-15 14:01:14 +0000332- Universal newlines (PEP 278) is implemented. Briefly, using 'U'
333 instead of 'r' when opening a text file for reading changes the line
334 ending convention so that any of '\r', '\r\n', and '\n' is
335 recognized (even mixed in one file); all three are converted to
336 '\n', the standard Python line end character.
337
Neal Norwitz649b7592002-01-01 19:07:13 +0000338- file.xreadlines() now raises a ValueError if the file is closed:
339 Previously, an xreadlines object was returned which would raise
340 a ValueError when the xreadlines.next() method was called.
341
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000342- sys.exit() inadvertently allowed more than one argument.
Neal Norwitz0c766a02002-03-27 13:03:09 +0000343 An exception will now be raised if more than one argument is used.
344
Gustavo Niemeyer17c5a332002-12-16 14:09:22 +0000345- Changed evaluation order of dictionary literals to conform to the
346 general left to right evaluation order rule. Now {f1(): f2()} will
347 evaluate f1 first.
Gustavo Niemeyer78429a62002-12-16 13:54:02 +0000348
Gustavo Niemeyer786ddb22002-12-16 18:12:53 +0000349- Fixed bug #521782: when a file was in non-blocking mode, file.read()
350 could silently lose data or wrongly throw an unknown error.
351
Neil Schemenauerb983aa02002-12-30 20:22:23 +0000352- The sq_repeat, sq_inplace_repeat, sq_concat and sq_inplace_concat
353 slots are now always tried after trying the corresponding nb_* slots.
354 This fixes a number of minor bugs (see bug #624807).
355
Tim Petersaf8446f2001-12-21 21:36:50 +0000356Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000357-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000358
Guido van Rossuma3b89532002-12-30 22:59:32 +0000359- A module zipimport exists to support importing code from zip
360 archives.
361
Tim Peterse820cb62002-12-16 20:57:22 +0000362- The new datetime module supplies classes for manipulating dates and
363 times. The basic design came from the Zope "fishbowl process", and
364 favors practical commercial applications over calendar esoterica. See
365
366 http://www.zope.org/Members/fdrake/DateTimeWiki/FrontPage
367
Martin v. Löwisffad6332002-11-26 09:28:05 +0000368- _tkinter now returns Tcl objects, instead of strings. Objects which
369 have Python equivalents are converted to Python objects, other objects
370 are wrapped. This can be configured through the wantobjects method,
Martin v. Löwis8c8aa5d2002-11-26 21:39:48 +0000371 or Tkinter.wantobjects.
Martin v. Löwisffad6332002-11-26 09:28:05 +0000372
Barry Warsawc27f4bd2002-12-30 21:03:26 +0000373- The PyBSDDB wrapper around the Sleepycat Berkeley DB library has
374 been added as the package bsddb. The traditional bsddb module is
375 still available in source code, but not built automatically anymore,
376 and is now named bsddb185. This supports Berkeley DB versions from
377 3.0 to 4.1.
Martin v. Löwisef546b32002-11-19 08:12:57 +0000378
Martin v. Löwis677bde22002-11-23 22:08:15 +0000379- unicodedata was updated to Unicode 3.2. It supports normalization
380 and names for Hangul syllables and CJK unified ideographs.
Martin v. Löwis7d41e292002-11-23 12:22:32 +0000381
Neal Norwitz94a83fd2002-11-02 17:46:24 +0000382- resource.getrlimit() now returns longs instead of ints.
383
Martin v. Löwis080689c2002-10-26 14:42:02 +0000384- readline now dynamically adjusts its input/output stream if
385 sys.stdin/stdout changes.
386
Guido van Rossumba602972002-10-01 18:18:58 +0000387- The _tkinter module (and hence Tkinter) has dropped support for
388 Tcl/Tk 8.0 and 8.1. Only Tcl/Tk versions 8.2, 8.3 and 8.4 are
389 supported.
390
Martin v. Löwis658009a2002-09-16 17:26:24 +0000391- cPickle.BadPickleGet is now a class.
392
Martin v. Löwisa19bfe02002-10-16 18:28:36 +0000393- The time stamps in os.stat_result are floating point numbers
394 after stat_float_times has been called.
Martin v. Löwis94717ed2002-09-09 14:24:16 +0000395
Neal Norwitzb5673922002-09-05 21:48:07 +0000396- If the size passed to mmap.mmap() is larger than the length of the
397 file on non-Windows platforms, a ValueError is raised. [SF bug 585792]
398
Guido van Rossumb57089c2002-08-06 16:20:26 +0000399- The xreadlines module is slated for obsolescence.
400
Guido van Rossum79f0a102002-07-23 03:32:08 +0000401- The strptime function in the time module is now always available (a
402 Python implementation is used when the C library doesn't define it).
403
Guido van Rossum9562bcf2002-06-14 21:31:18 +0000404- The 'new' module is no longer an extension, but a Python module that
405 only exists for backwards compatibility. Its contents are no longer
406 functions but callable type objects.
407
Tim Peters81b92512002-04-29 01:37:32 +0000408- The bsddb.*open functions can now take 'None' as a filename.
Anthony Baxter83888952002-04-23 02:11:05 +0000409 This will create a temporary in-memory bsddb that won't be
Tim Peters81b92512002-04-29 01:37:32 +0000410 written to disk.
Anthony Baxter83888952002-04-23 02:11:05 +0000411
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +0000412- posix.lchown, posix.killpg, posix.mknod, and posix.getpgid have been
413 added where available.
Martin v. Löwis06a83e92002-04-14 10:19:44 +0000414
Martin v. Löwisf0a46682002-11-03 17:20:12 +0000415- The locale module now exposes the C library's gettext interface. It
416 also has a new function getpreferredencoding.
Martin v. Löwis2e64c342002-03-27 18:49:02 +0000417
Tim Petersfbf74f22002-03-14 19:06:01 +0000418- A security hole ("double free") was found in zlib-1.1.3, a popular
419 third party compression library used by some Python modules. The
420 hole was quickly plugged in zlib-1.1.4, and the Windows build of
421 Python now ships with zlib-1.1.4.
422
Martin v. Löwis688357e2002-04-08 21:28:20 +0000423- pwd, grp, and resource return enhanced tuples now, with symbolic
424 field names.
Martin v. Löwis29001ff2002-03-01 10:47:37 +0000425
Martin v. Löwis99866332002-03-01 10:27:01 +0000426- array.array is now a type object. A new format character
427 'u' indicates Py_UNICODE arrays. For those, .tounicode and
428 .fromunicode methods are available. Arrays now support __iadd__
429 and __imul__.
430
Neal Norwitze790eae2002-01-01 21:14:12 +0000431- dl now builds on every system that has dlfcn.h. Failure in case
Martin v. Löwis93227272002-01-01 20:18:30 +0000432 of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
433 is called.
434
Michael W. Hudson34f20ea2002-05-27 15:08:24 +0000435- signal.sigpending, signal.sigprocmask and signal.sigsuspend have
436 been added where available.
437
Skip Montanaro8e790e72002-09-03 13:25:17 +0000438- The sys module acquired a new attribute, api_version, which evaluates
439 to the value of the PYTHON_API_VERSION macro with which the
440 interpreter was compiled.
441
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000442- Fixed bug #470582: sre module would return a tuple (None, 'a', 'ab')
443 when applying the regular expression '^((a)c)?(ab)$' on 'ab'. It now
444 returns (None, None, 'ab'), as expected. Also fixed handling of
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +0000445 lastindex/lastgroup match attributes in similar cases. For example,
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000446 when running the expression r'(a)(b)?b' over 'ab', lastindex must be
447 1, not 2.
448
Gustavo Niemeyerc523b042002-11-07 03:28:56 +0000449- Fixed bug #581080: sre scanner was not checking the buffer limit
450 before increasing the current pointer. This was creating an infinite
451 loop in the search function, once the pointer exceeded the buffer
452 limit.
453
Thomas Heller95cb7e42002-11-07 16:23:55 +0000454- The os.fdopen function now enforces a file mode starting with the
455 letter 'r', 'w' or 'a', otherwise a ValueError is raised. This fixes
456 bug #623464.
457
Tim Petersaf8446f2001-12-21 21:36:50 +0000458Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000459-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000460
Raymond Hettingeraf72d522002-12-29 20:14:11 +0000461- unittest.py now has two additional methods called assertAlmostEqual()
462 and failIfAlmostEqual(). They implement an approximate comparision
463 by rounding the difference between the two arguments and comparing
464 the result to zero. Approximate comparision is essential for
465 unit tests of floating point results.
466
Raymond Hettingere11b5102002-12-25 16:37:19 +0000467- calendar.py now depends on the new datetime module rather than
468 the time module. As a result, the range of allowable dates
469 has been increased.
470
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000471- pdb has a new 'j(ump)' command to select the next line to be
472 executed.
473
Thomas Heller1b3b49d2002-12-12 19:13:44 +0000474- The distutils created windows installers now can run a
475 postinstallation script.
476
Martin v. Löwis4581cfa2002-11-22 08:23:09 +0000477- doctest.testmod can now be called without argument, which means to
478 test the current module.
479
Martin v. Löwisf86e8ef2002-11-22 08:08:44 +0000480- When cancelling a server that implemented threading with a keyboard
481 interrupt, the server would shut down but not terminate (waiting on
482 client threads). A new member variable, daemon_threads, was added to
483 the ThreadingMixIn class in SocketServer.py to make it explicit that
484 this behavior needs to be controlled.
485
Guido van Rossum545c2502002-11-15 13:19:58 +0000486- A new module, optparse, provides a fancy alternative to getopt for
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000487 command line parsing. It is a slightly modified version of Greg
Guido van Rossum545c2502002-11-15 13:19:58 +0000488 Ward's Optik package.
489
Raymond Hettinger79947162002-11-15 06:46:14 +0000490- UserDict.py now defines a DictMixin class which defines all dictionary
491 methods for classes that already have a minimum mapping interface.
492 This greatly simplifies writing classes that need to be substitutable
493 for dictionaries (such as the shelve module).
494
495- shelve.py now subclasses from UserDict.DictMixin. Now shelve supports
496 all dictionary methods. This eases the transition to persistent
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000497 storage for scripts originally written with dictionaries in mind.
Raymond Hettinger79947162002-11-15 06:46:14 +0000498
Skip Montanaro3bf99e32002-12-08 18:36:24 +0000499- shelve.open and the various classes in shelve.py now accept an optional
500 binary flag, which defaults to False. If True, the values stored in the
501 shelf are binary pickles.
502
Guido van Rossumfda06742002-11-13 16:29:18 +0000503- A new package, logging, implements the logging API defined by PEP
504 282. The code is written by Vinay Sajip.
505
Walter Dörwald4dbf1922002-11-06 16:53:44 +0000506- StreamReader, StreamReaderWriter and StreamRecoder in the codecs
507 modules are iterators now.
508
Tim Peters9288f952002-11-05 20:38:55 +0000509- gzip.py now handles files exceeding 2GB. Files over 4GB also work
510 now (provided the OS supports it, and Python is configured with large
511 file support), but in that case the underlying gzip file format can
512 record only the least-significant 32 bits of the file size, so that
513 some tools working with gzipped files may report an incorrect file
514 size.
Tim Petersfb0ea522002-11-04 19:50:11 +0000515
Martin v. Löwis74b51ac2002-10-26 14:50:45 +0000516- xml.sax.saxutils.unescape has been added, to replace entity references
517 with their entity value.
518
Martin v. Löwis77ac4292002-10-15 15:11:13 +0000519- Queue.Queue.{put,get} now support an optional timeout argument.
520
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000521- Various features of Tk 8.4 are exposed in Tkinter.py. The multiple
522 option of tkFileDialog is exposed as function askopenfile{,name}s.
Martin v. Löwis2ec36272002-10-13 10:22:08 +0000523
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000524- Various configure methods of Tkinter have been stream-lined, so that
525 tag_configure, image_configure, window_configure now return a
Tim Petersfb0ea522002-11-04 19:50:11 +0000526 dictionary when invoked with no argument.
Martin v. Löwis6ce13152002-10-10 14:36:13 +0000527
Guido van Rossum2b492b62002-10-09 21:40:48 +0000528- Importing the readline module now no longer has the side effect of
529 calling setlocale(LC_CTYPE, ""). The initial "C" locale, or
530 whatever locale is explicitly set by the user, is preserved. If you
531 want repr() of 8-bit strings in your preferred encoding to preserve
532 all printable characters of that encoding, you have to add the
533 following code to your $PYTHONSTARTUP file or to your application's
534 main():
535
536 import locale
537 locale.setlocale(locale.LC_CTYPE, "")
538
Martin v. Löwise9ce0b02002-10-07 13:23:24 +0000539- shutil.move was added. shutil.copytree now reports errors as an
540 exception at the end, instead of printing error messages.
541
Marc-André Lemburg97047e22002-10-04 11:55:21 +0000542- Encoding name normalization was generalized to not only
543 replace hyphens with underscores, but also all other non-alphanumeric
544 characters (with the exception of the dot which is used for Python
545 package names during lookup). The aliases.py mapping was updated
546 to the new standard.
547
Walter Dörwald5ccaf8f2002-09-06 16:15:58 +0000548- mimetypes has two new functions: guess_all_extensions() which
549 returns a list of all known extensions for a mime type, and
550 add_type() which adds one mapping between a mime type and
551 an extension to the database.
552
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000553- New module: sets, defines the class Set that implements a mutable
554 set type using the keys of a dict to represent the set. There's
555 also a class ImmutableSet which is useful when you need sets of sets
556 or when you need to use sets as dict keys, and a class BaseSet which
Raymond Hettingeref8b9c62002-12-09 08:56:06 +0000557 is the base class of the two.
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000558
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000559- Added operator.pow(a,b) which is equivalent to a**b.
560
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000561- Added random.sample(population,k) for random sampling without replacement.
Tim Petersb9099c32002-11-12 22:08:10 +0000562 Returns a k length list of unique elements chosen from the population.
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000563
Tim Peters012c0a32002-08-16 03:40:07 +0000564- random.randrange(-sys.maxint-1, sys.maxint) no longer raises
565 OverflowError. That is, it now accepts any combination of 'start'
566 and 'stop' arguments so long as each is in the range of Python's
567 bounded integers.
568
Raymond Hettinger40f62172002-12-29 23:03:38 +0000569- Thanks to Raymond Hettinger, random.random() now uses a new core
570 generator. The Mersenne Twister algorithm is implemented in C,
571 threadsafe, faster than the previous generator, has an astronomically
572 large period (2**19937-1), creates random floats to full 53-bit
573 precision, and may be the most widely tested random number generator
574 in existence.
575
576 The random.jumpahead(n) method has different semantics for the new
577 generator. Instead of jumping n steps ahead, it uses n and the
578 existing state to create a new state. This means that jumpahead()
579 continues to support multi-threaded code needing generators of
580 non-overlapping sequences. However, it will break code which relies
581 on jumpahead moving a specific number of steps forward.
582
583 The attributes random.whseed and random.__whseed have no meaning for
584 the new generator. Code using these attributes should switch to a
585 new class, random.WichmannHill which is provided for backward
586 compatibility and to make an alternate generator available.
587
Guido van Rossum4a57c332002-08-02 18:05:20 +0000588- New "algorithms" module: heapq, implements a heap queue. Thanks to
589 Kevin O'Connor for the code and François Pinard for an entertaining
590 write-up explaining the theory and practical uses of heaps.
591
Marc-André Lemburg58e2ff22002-07-12 14:40:04 +0000592- New encoding for the Palm OS character set: palmos.
593
Tim Peters943382c2002-07-07 03:59:34 +0000594- binascii.crc32() and the zipfile module had problems on some 64-bit
595 platforms. These have been fixed. On a platform with 8-byte C longs,
596 crc32() now returns a signed-extended 4-byte result, so that its value
597 as a Python int is equal to the value computed a 32-bit platform.
598
Martin v. Löwis7d650ca2002-06-30 15:05:00 +0000599- xml.dom.minidom.toxml and toprettyxml now take an optional encoding
600 argument.
601
Guido van Rossum9f7549b2002-06-10 21:39:42 +0000602- Some fixes in the copy module: when an object is copied through its
603 __reduce__ method, there was no check for a __setstate__ method on
604 the result [SF patch 565085]; deepcopy should treat instances of
605 custom metaclasses the same way it treats instances of type 'type'
606 [SF patch 560794].
607
Guido van Rossum5033c8e2002-06-07 12:40:52 +0000608- Sockets now support timeout mode. After s.settimeout(T), where T is
609 a float expressing seconds, subsequent operations raise an exception
610 if they cannot be completed within T seconds. To disable timeout
Guido van Rossum79f0a102002-07-23 03:32:08 +0000611 mode, use s.settimeout(None). There's also a module function,
612 socket.setdefaulttimeout(T), which sets the default for all sockets
613 created henceforth.
Guido van Rossum5033c8e2002-06-07 12:40:52 +0000614
615- getopt.gnu_getopt was added. This supports GNU-style option
616 processing, where options can be mixed with non-option arguments.
Martin v. Löwis446a25f2002-06-06 10:58:36 +0000617
Michael W. Hudsonb0dc1a32002-06-04 18:27:35 +0000618- Stop using strings for exceptions. String objects used for
619 exceptions are now classes deriving from Exception. The objects
620 changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
621 tabnanny.NannyNag, and xdrlib.Error.
Neal Norwitzb5b5a262002-06-04 17:14:07 +0000622
Walter Dörwald474458d2002-06-04 15:16:29 +0000623- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
624 BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
625 Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
626 big endian systems were added to the codecs module. The old names
627 BOM32_* and BOM64_* were off by a factor of 2.
628
Guido van Rossumf9257822002-06-18 20:43:18 +0000629- Added conversion functions math.degrees() and math.radians().
Raymond Hettinger87f59ee2002-05-13 04:17:32 +0000630
Raymond Hettinger866964c2002-12-14 19:51:34 +0000631- math.log() now takes an optional argument: math.log(x[, base]).
632
Raymond Hettinger9b1df1d2002-05-12 06:07:21 +0000633- ftplib.retrlines() now tests for callback is None rather than testing
634 for False. Was causing an error when given a callback object which
635 was callable but also returned len() as zero. The change may
636 create new breakage if the caller relied on the undocumented behavior
637 and called with callback set to [] or some other False value not
638 identical to None.
639
Tim Peters46c04e12002-05-05 20:40:00 +0000640- random.gauss() uses a piece of hidden state used by nothing else,
641 and the .seed() and .whseed() methods failed to reset it. In other
642 words, setting the seed didn't completely determine the sequence of
643 results produced by random.gauss(). It does now. Programs repeatedly
644 mixing calls to a seed method with calls to gauss() may see different
645 results now.
646
Fred Drake7f781c92002-05-01 20:33:53 +0000647- The pickle.Pickler class grew a clear_memo() method to mimic that
648 provided by cPickle.Pickler.
649
Tim Peters81b92512002-04-29 01:37:32 +0000650- difflib's SequenceMatcher class now does a dynamic analysis of
651 which elements are so frequent as to constitute noise. For
652 comparing files as sequences of lines, this generally works better
653 than the IS_LINE_JUNK function, and function ndiff's linejunk
654 argument defaults to None now as a result. A happy benefit is
655 that SequenceMatcher may run much faster now when applied
656 to large files with many duplicate lines (for example, C program
657 text with lots of repeated "}" and "return NULL;" lines).
658
Guido van Rossum256705b2002-04-23 13:29:43 +0000659- New Text.dump() method in Tkinter module.
660
Marc-André Lemburg1ec71ea2002-04-17 20:33:40 +0000661- New distutils commands for building packagers were added to
662 support pkgtool on Solaris and swinstall on HP-UX.
663
664- distutils now has a new abstract binary packager base class
665 command/bdist_packager, which simplifies writing packagers.
666 This will hopefully provide the missing bits to encourage
667 people to submit more packagers, e.g. for Debian, FreeBSD
668 and other systems.
669
Guido van Rossumf9257822002-06-18 20:43:18 +0000670- The UTF-16, -LE and -BE stream readers now raise a
671 NotImplementedError for all calls to .readline(). Previously, they
672 used to just produce garbage or fail with an encoding error --
673 UTF-16 is a 2-byte encoding and the C lib's line reading APIs don't
Marc-André Lemburg4179a012002-04-05 12:15:05 +0000674 work well with these.
675
Martin v. Löwis5c137c22002-03-18 12:44:08 +0000676- compileall now supports quiet operation.
677
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000678- The BaseHTTPServer now implements optional HTTP/1.1 persistent
Martin v. Löwis587c98c2002-03-17 18:37:22 +0000679 connections.
680
Marc-André Lemburga5d2b4c2002-02-16 18:23:30 +0000681- socket module: the SSL support was broken out of the main
682 _socket module C helper and placed into a new _ssl helper
683 which now gets imported by socket.py if available and working.
684
Marc-André Lemburg37aa5802002-02-10 21:42:47 +0000685- encodings package: added aliases for all supported IANA character
686 sets
687
Guido van Rossum606fe4e2001-12-28 20:57:14 +0000688- ftplib: to safeguard the user's privacy, anonymous login will use
689 "anonymous@" as default password, rather than the real user and host
690 name.
691
Fred Drake36736122002-01-10 13:50:31 +0000692- webbrowser: tightened up the command passed to os.system() so that
693 arbitrary shell code can't be executed because a bogus URL was
694 passed in.
695
Tim Peters11bd9942002-02-01 00:52:29 +0000696- gettext.translation has an optional fallback argument, and
Martin v. Löwisa55ffae2002-01-11 06:58:49 +0000697 gettext.find an optional all argument. Translations will now fallback
Martin v. Löwisd8996052002-11-21 21:45:32 +0000698 on a per-message basis. The module supports plural forms, by means
699 of gettext.[d]ngettext and Translation.[u]ngettext.
Martin v. Löwis1be64192002-01-11 06:33:28 +0000700
Martin v. Löwis9668b932002-01-12 11:27:42 +0000701- distutils bdist commands now offer a --skip-build option.
702
Walter Dörwaldb25c2b02002-03-21 10:38:40 +0000703- warnings.warn now accepts a Warning instance as first argument.
704
Fred Drakefed7e852002-04-04 19:36:15 +0000705- The xml.sax.expatreader.ExpatParser class will no longer create
706 circular references by using itself as the locator that gets passed
707 to the content handler implementation. [SF bug #535474]
708
Barry Warsaw47f3e2c2002-05-20 00:14:24 +0000709- The email.Parser.Parser class now properly parses strings regardless
710 of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
711 or CRLF). Also, the Header class's constructor default arguments
712 has changed slightly so that an explicit maxlinelen value is always
Barry Warsaw497e5c42002-12-30 19:27:08 +0000713 honored, and so unicode conversion error handling can be specified.
Barry Warsaw47f3e2c2002-05-20 00:14:24 +0000714
Gustavo Niemeyerf8ca8362002-11-05 16:50:05 +0000715- distutils' build_ext command now links c++ extensions with the c++
716 compiler available in the Makefile or CXX environment variable, if
717 running under *nix.
718
719- New module bz2: provides a comprehensive interface for the bz2 compression
720 library. It implements a complete file interface, one-shot (de)compression
721 functions, and types for sequential (de)compression.
722
Barry Warsaw5d8d6182002-11-05 22:41:33 +0000723- New pdb command `pp' which is like `p' except that it pretty-prints
724 the value of its expression argument.
725
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +0000726- Now bdist_rpm distutils command understands a verify_script option in
727 the config file, including the contents of the referred filename in
728 the "%verifyscript" section of the rpm spec file.
729
Gustavo Niemeyer1456fde2002-11-25 17:25:04 +0000730- Fixed bug #495695: webbrowser module would run graphic browsers in a
731 unix environment even if DISPLAY was not set. Also, support for
732 skipstone browser was included.
733
Gustavo Niemeyerd5ae01a2002-12-16 13:11:57 +0000734- Fixed bug #636769: rexec would run unallowed code if subclasses of
735 strings were used as parameters for certain functions.
736
Tim Petersaf8446f2001-12-21 21:36:50 +0000737Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000738-----------
Tim Petersaf8446f2001-12-21 21:36:50 +0000739
Martin v. Löwis0d1fdea2002-11-22 08:36:54 +0000740- pygettext.py now supports globbing on Windows, and accepts module
741 names in addition to accepting file names.
742
Guido van Rossum923e4ef2002-09-17 20:58:59 +0000743- The SGI demos (Demo/sgi) have been removed. Nobody thought they
744 were interesting any more. (The SGI library modules and extensions
745 are still there; it is believed that at least some of these are
746 still used and useful.)
747
Fred Drake40813b12002-08-05 15:24:19 +0000748- IDLE supports the new encoding declarations (PEP 263); it can also
749 deal with legacy 8-bit files if they use the locale's encoding. It
750 allows non-ASCII strings in the interactive shell and executes them
751 in the locale's encoding.
Martin v. Löwis98ce7b72002-08-05 15:11:26 +0000752
Marc-André Lemburg46260092002-04-04 16:17:11 +0000753- freeze.py now produces binaries which can import shared modules,
754 unlike before when this failed due to missing symbol exports in
755 the generated binary.
756
Tim Petersaf8446f2001-12-21 21:36:50 +0000757Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000758-----
Tim Petersaf8446f2001-12-21 21:36:50 +0000759
Guido van Rossumacd738f2002-12-30 21:04:23 +0000760- Makefile.pre.in now adds @CFLAGS@ and @CPPFLAGS@ to their respective
761 variable definitions.
762
Martin v. Löwisdc461752002-11-06 21:59:33 +0000763- On Unix, IDLE is now installed automatically.
764
Guido van Rossum6b3db552002-09-25 15:02:44 +0000765- The fpectl module is not built by default; it's dangerous or useless
766 except in the hands of experts.
767
Tim Petersf47630f2002-08-01 02:34:51 +0000768- The public Python C API will generally be declared using PyAPI_FUNC
Guido van Rossum6b3db552002-09-25 15:02:44 +0000769 and PyAPI_DATA macros, while Python extension module init functions
770 will be declared with PyMODINIT_FUNC. DL_EXPORT/DL_IMPORT macros
771 are deprecated.
Neal Norwitz1389f3e2002-07-22 13:21:10 +0000772
Tim Petersc6a3ff62002-07-08 22:11:52 +0000773- A bug was fixed that could cause COUNT_ALLOCS builds to segfault, or
774 get into infinite loops, when a new-style class got garbage-collected.
775 Unfortunately, to avoid this, the way COUNT_ALLOCS works requires
776 that new-style classes be immortal in COUNT_ALLOCS builds. Note that
777 COUNT_ALLOCS is not enabled by default, in either release or debug
778 builds, and that new-style classes are immortal only in COUNT_ALLOCS
779 builds.
780
Tim Peters943382c2002-07-07 03:59:34 +0000781- Compiling out the cyclic garbage collector is no longer an option.
782 The old symbol WITH_CYCLE_GC is now ignored, and Python.h arranges
783 that it's always defined (for the benefit of any extension modules
784 that may be conditionalizing on it). A bonus is that any extension
785 type participating in cyclic gc can choose to participate in the
786 Py_TRASHCAN mechanism now too; in the absence of cyclic gc, this used
787 to require editing the core to teach the trashcan mechanism about the
788 new type.
789
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +0000790- According to Annex F of the current C standard,
Tim Peters1de41bf2002-07-03 03:31:20 +0000791
792 The Standard C macro HUGE_VAL and its float and long double analogs,
793 HUGE_VALF and HUGE_VALL, expand to expressions whose values are
794 positive infinities.
795
796 Python only uses the double HUGE_VAL, and only to #define its own symbol
797 Py_HUGE_VAL. Some platforms have incorrect definitions for HUGE_VAL.
798 pyport.h used to try to worm around that, but the workarounds triggered
799 other bugs on other platforms, so we gave up. If your platform defines
800 HUGE_VAL incorrectly, you'll need to #define Py_HUGE_VAL to something
801 that works on your platform. The only instance of this I'm sure about
802 is on an unknown subset of Cray systems, described here:
803
804 http://www.cray.com/swpubs/manuals/SN-2194_2.0/html-SN-2194_2.0/x3138.htm
805
806 Presumably 2.3a1 breaks such systems. If anyone uses such a system, help!
807
Martin v. Löwisa3fb4f72002-06-09 13:33:54 +0000808- The configure option --without-doc-strings can be used to remove the
809 doc strings from the builtin functions and modules; this reduces the
810 size of the executable.
811
Guido van Rossumadd88062002-08-15 14:01:14 +0000812- The universal newlines option (PEP 278) is on by default. On Unix
813 it can be disabled by passing --without-universal-newlines to the
814 configure script. On other platforms, remove
815 WITH_UNIVERSAL_NEWLINES from pyconfig.h.
Tim Peters639295f2002-04-21 07:30:30 +0000816
Martin v. Löwis1142de32002-03-29 16:28:31 +0000817- On Unix, a shared libpython2.3.so can be created with --enable-shared.
818
Tim Peters8deda702002-03-30 10:06:07 +0000819- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
820 preprocessor symbols were eliminated. The internal decisions they
821 controlled stopped being experimental long ago.
Tim Peters1f7df352002-03-29 03:29:08 +0000822
Fred Drake7d28b732002-05-02 21:17:00 +0000823- The tools used to build the documentation now work under Cygwin as
824 well as Unix.
825
Skip Montanaro57454e52002-06-14 20:30:31 +0000826- The bsddb and dbm module builds have been changed to try and avoid version
827 skew problems and disable linkage with Berkeley DB 1.85 unless the
828 installer knows what s/he's doing. See the section on building these
829 modules in the README file for details.
830
Tim Petersaf8446f2001-12-21 21:36:50 +0000831C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000832-----
Tim Petersaf8446f2001-12-21 21:36:50 +0000833
Neil Schemenauer6c194762002-11-18 16:19:39 +0000834- PyNumber_Check() now returns true for string and unicode objects.
835 This is a result of these types having a partially defined
Guido van Rossum1d267402002-11-18 16:27:16 +0000836 tp_as_number slot. (This is not a feature, but an indication that
Walter Dörwalda1a61f92002-11-19 21:20:25 +0000837 PyNumber_Check() is not very useful to determine numeric behavior.
Guido van Rossum1d267402002-11-18 16:27:16 +0000838 It may be deprecated.)
Neil Schemenauer6c194762002-11-18 16:19:39 +0000839
Guido van Rossum45ec02a2002-08-19 21:43:18 +0000840- The string object's layout has changed: the pointer member
841 ob_sinterned has been replaced by an int member ob_sstate. On some
842 platforms (e.g. most 64-bit systems) this may change the offset of
843 the ob_sval member, so as a precaution the API_VERSION has been
844 incremented. The apparently unused feature of "indirect interned
845 strings", supported by the ob_sinterned member, is gone. Interned
846 strings are now usually mortal; theres a new API,
847 PyString_InternImmortal() that creates immortal interned strings.
848 (The ob_sstate member can only take three values; however, while
849 making it a char saves a few bytes per string object on average, in
850 it also slowed things down a bit because ob_sval was no longer
851 aligned.)
852
Guido van Rossumfdb86482002-08-14 21:20:32 +0000853- The Py_InitModule*() functions now accept NULL for the 'methods'
854 argument. Modules without global functions are becoming more common
855 now that factories can be types rather than functions.
856
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000857- New C API PyUnicode_FromOrdinal() which exposes unichr() at C
858 level.
859
Thomas Heller085358a2002-07-29 14:27:41 +0000860- New functions PyErr_SetExcFromWindowsErr() and
861 PyErr_SetExcFromWindowsErrWithFilename(). Similar to
862 PyErr_SetFromWindowsErrWithFilename() and
863 PyErr_SetFromWindowsErr(), but they allow to specify
864 the exception type to raise. Available on Windows.
865
Tim Peters7c321a82002-07-09 02:57:01 +0000866- Py_FatalError() is now declared as taking a const char* argument. It
867 was previously declared without const. This should not affect working
868 code.
869
Martin v. Löwis01f94bd2002-05-08 08:44:21 +0000870- Added new macro PySequence_ITEM(o, i) that directly calls
871 sq_item without rechecking that o is a sequence and without
872 adjusting for negative indices.
873
Fred Draked0ba6362002-05-02 21:28:26 +0000874- PyRange_New() now raises ValueError if the fourth argument is not 1.
875 This is part of the removal of deprecated features of the xrange
876 object.
877
Guido van Rossum517c7d42002-04-26 02:49:14 +0000878- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
879 coercion if both arguments have the same type but this type has the
880 CHECKTYPES flag set. This is to better support proxies.
881
Skip Montanaroa2a07bc2002-09-30 15:23:01 +0000882- The type of tp_free has been changed from "``void (*)(PyObject *)``" to
883 "``void (*)(void *)``".
Neil Schemenauer9344b142002-04-12 23:00:08 +0000884
885- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
886
Guido van Rossum0986d822002-04-08 01:38:42 +0000887- A type can now inherit its metatype from its base type. Previously,
888 when PyType_Ready() was called, if ob_type was found to be NULL, it
889 was always set to &PyType_Type; now it is set to base->ob_type,
890 where base is tp_base, defaulting to &PyObject_Type.
891
892- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
893
Neil Schemenauerc9abc1d2002-05-08 14:14:41 +0000894- The PyCore_* family of APIs have been removed.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000895
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000896- The "u#" parser marker will now pass through Unicode objects as-is
Marc-André Lemburg3e3eacb2002-01-09 16:21:27 +0000897 without going through the buffer API.
898
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000899- The enumerators of cmp_op have been renamed to use the prefix ``PyCmp_``.
Martin v. Löwis7198a522002-01-01 19:59:11 +0000900
Tim Peters10a3bb52001-12-25 19:07:38 +0000901- An old #define of ANY as void has been removed from pyport.h. This
902 hasn't been used since Python's pre-ANSI days, and the #define has
903 been marked as obsolete since then. SF bug 495548 says it created
904 conflicts with other packages, so keeping it around wasn't harmless.
905
Tim Petersaf8446f2001-12-21 21:36:50 +0000906- Because Python's magic number scheme broke on January 1st, we decided
907 to stop Python development. Thanks for all the fish!
908
Tim Petersfb05db22002-03-11 00:24:00 +0000909- Some of us don't like fish, so we changed Python's magic number
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000910 scheme to a new one. See Python/import.c for details.
911
Tim Petersaf8446f2001-12-21 21:36:50 +0000912New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000913-------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000914
Martin v. Löwis79acb9e2002-12-06 12:48:53 +0000915- OpenVMS is now supported.
916
Martin v. Löwisf90ae202002-06-11 06:22:31 +0000917- AtheOS is now supported.
918
Andrew MacIntyre161ad0e2002-08-04 07:25:58 +0000919- the EMX runtime environment on OS/2 is now supported.
920
Martin v. Löwisa6e97582002-01-01 18:41:33 +0000921- GNU/Hurd is now supported.
922
Tim Petersaf8446f2001-12-21 21:36:50 +0000923Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000924-----
925
Fred Drake4dd0f7e2002-11-26 21:44:56 +0000926- The regrtest.py script's -u option now provides a way to say "allow
927 all resources except this one." For example, to allow everything
928 except bsddb, give the option '-uall,-bsddb'.
Tim Petersaf8446f2001-12-21 21:36:50 +0000929
930Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000931-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000932
Tim Peters19cf4ee2002-11-23 03:49:08 +0000933- The Windows distribution now ships with version 4.0.14 of the
934 Sleepycat Berkeley database library. This should be a huge
935 improvement over the previous Berkeley DB 1.85, which had many
936 bugs.
937 XXX What are the licensing issues here?
Tim Peters84c7a3f2002-11-23 18:48:06 +0000938 XXX If a user has a database created with a previous verion of
939 XXX Python, what must they do to convert it?
940 XXX I'm still not sure how to link this thing (see PCbuild/readme.txt).
Tim Peters19cf4ee2002-11-23 03:49:08 +0000941 XXX The version # is likely to change before 2.3a1.
Tim Peterse820cb62002-12-16 20:57:22 +0000942
943- The Windows distribution now ships with a Secure Sockets Library (SLL)
Mark Hammondc3de0082002-12-03 06:16:08 +0000944 module (_ssl.pyd)
Tim Peters19cf4ee2002-11-23 03:49:08 +0000945
Tim Peters857fb4c2002-11-14 23:31:58 +0000946- The Windows distribution now ships with Tcl/Tk version 8.4.1 (it
947 previously shipped with Tcl/Tk 8.3.2).
948
Tim Peters37dfb012002-11-11 19:51:33 +0000949- When Python is built under a Microsoft compiler, sys.version now
950 includes the compiler version number (_MSC_VER). For example, under
951 MSVC 6, sys.version constains the substring "MSC v.1200 ". 1200 is
952 the value of _MSC_VER under MSVC 6.
953
Tim Peters08e72952002-04-16 20:48:01 +0000954- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
955 of that has been fixed in the installer (disabled Wise's "delete in-
956 use files" uninstall option).
957
Guido van Rossum181e41a2002-04-06 00:23:25 +0000958- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
959
Tim Peters33187922002-04-04 20:02:04 +0000960- The installer now installs Start menu shortcuts under (the local
961 equivalent of) "All Users" when doing an Admin install.
962
Tim Petersfb05db22002-03-11 00:24:00 +0000963- file.truncate([newsize]) now works on Windows for all newsize values.
964 It used to fail if newsize didn't fit in 32 bits, reflecting a
965 limitation of MS _chsize (which is no longer used).
966
Tim Petersab034fa2002-02-01 11:27:43 +0000967- os.waitpid() is now implemented for Windows, and can be used to block
968 until a specified process exits. This is similar to, but not exactly
969 the same as, os.waitpid() on POSIX systems. If you're waiting for
970 a specific process whose pid was obtained from one of the spawn()
971 functions, the same Python os.waitpid() code works across platforms.
Tim Peters33187922002-04-04 20:02:04 +0000972 See the docs for details. The docs were changed to clarify that
973 spawn functions return, and waitpid requires, a process handle on
974 Windows (not the same thing as a Windows process id).
Tim Petersab034fa2002-02-01 11:27:43 +0000975
Tim Peters11bd9942002-02-01 00:52:29 +0000976- New tempfile.TemporaryFile implementation for Windows: this doesn't
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000977 need a TemporaryFileWrapper wrapper anymore, and should be immune
Tim Peters11bd9942002-02-01 00:52:29 +0000978 to a nasty problem: before 2.3, if you got a temp file on Windows, it
979 got wrapped in an object whose close() method first closed the
980 underlying file, then deleted the file. This usually worked fine.
981 However, the spawn family of functions on Windows create (at a low C
982 level) the same set of open files in the spawned process Q as were
983 open in the spawning process P. If a temp file f was among them, then
984 doing f.close() in P first closed P's C-level file handle on f, but Q's
985 C-level file handle on f remained open, so the attempt in P to delete f
986 blew up with a "Permission denied" error (Windows doesn't allow
987 deleting open files). This was surprising, subtle, and difficult to
988 work around.
989
990- The os module now exports all the symbolic constants usable with the
991 low-level os.open() on Windows: the new constants in 2.3 are
992 O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
993 The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
994 O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
995 to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
996 (so specify both if you want both; note that neither is useful unless
997 specified with O_CREAT too).
998
Tim Petersaf8446f2001-12-21 21:36:50 +0000999Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001000----
1001
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001002- Mac/Relnotes is gone, the release notes are now here.
Tim Petersaf8446f2001-12-21 21:36:50 +00001003
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001004- The current naming convention for Python on the Macintosh is that MacPython
1005 refers to the unix-based OSX-only version, and MacPython-OS9 refers to the
1006 CFM-based version that runs on both OS9 and OSX.
1007
1008- All MacPython-OS9 functionality is now available in an OSX unix build,
1009 including the Carbon modules, the IDE, OSA support, etc. A lot of this
1010 will only work correctly in a framework build, though, because you cannot
1011 talk to the window manager unless your application is run from a .app
1012 bundle. There is a command line tool "pythonw" that runs your script
1013 with an interpreter living in such a .app bundle, this interpreter should
1014 be used to run any Python script using the window manager (including
1015 Tkinter or wxPython scripts).
Jack Jansen8bb80db2002-12-30 22:42:43 +00001016
1017- Most of Mac/Lib has moved to Lib/plat-mac, which is again used both in
1018 MacPython-OSX and MacPython-OS9. The only modules remaining in Mac/Lib
1019 are specifically for MacPython-OS9 (CFM support, preference resources, etc).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001020
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001021- A new utility PythonLauncher will start a Python interpreter when a .py or
1022 .pyw script is double-clicked in the Finder. By default .py scripts are
1023 run with a normal Python interpreter in a Terminal window and .pyw
1024 files are run with a window-aware pythonw interpreter without a Terminal
1025 window, but all this can be customized.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001026
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001027- MacPython-OS9 is now Carbon-only, so it runs on Mac OS 9 or Mac OS X and
1028 possibly on Mac OS 8.6 with the right CarbonLib installed, but not on earlier
1029 releases.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001030
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001031- Many tools such as BuildApplet.py and gensuitemodule.py now support a command
1032 line interface too.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001033
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001034- All the Carbon classes are now PEP253 compliant, meaning that you can
1035 subclass them from Python. Most of the attributes have gone, you should
1036 now use the accessor function call API, which is also what Apple's
1037 documentation uses. Some attributes such as grafport.visRgn are still
1038 available for convenience.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001039
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001040- New Carbon modules File (implementing the APIs in Files.h and Aliases.h)
1041 and Folder (APIs from Folders.h). The old macfs builtin module is
1042 gone, and replaced by a Python wrapper around the new modules.
1043
1044- Pathname handling should now be fully consistent: MacPython-OSX always uses
1045 unix pathnames and MacPython-OS9 always uses colon-separated Mac pathnames
1046 (also when running on Mac OS X).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001047
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001048- New Carbon modules Help and AH give access to the Carbon Help Manager.
1049 There are hooks in the IDE to allow accessing the Python documentation
1050 (and Apple's Carbon and Cocoa documentation) through the Help Viewer.
1051 See Mac/OSX/README for converting the Python documentation to a
1052 Help Viewer comaptible form and installing it.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001053
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001054- OSA support has been redesigned and the generated Python classes now
1055 mirror the inheritance defined by the underlying OSA classes.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001056
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001057- MacPython no longer maps both \r and \n to \n on input for any text file.
1058 This feature has been replaced by universal newline support (PEP278).
Tim Petersaf8446f2001-12-21 21:36:50 +00001059
Tim Peters909c0912001-12-14 23:16:18 +00001060What's New in Python 2.2 final?
Tim Peters909c0912001-12-14 23:16:18 +00001061===============================
1062
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001063*Release date: 21-Dec-2001*
1064
Tim Peters909c0912001-12-14 23:16:18 +00001065Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001066--------------------------------------------
Tim Peters909c0912001-12-14 23:16:18 +00001067
Barry Warsaw52acb492001-12-21 20:04:22 +00001068- pickle.py, cPickle: allow pickling instances of new-style classes
1069 with a custom metaclass.
1070
Tim Peters909c0912001-12-14 23:16:18 +00001071Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001072-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001073
Barry Warsaw52acb492001-12-21 20:04:22 +00001074- weakref proxy object: when comparing, unwrap both arguments if both
1075 are proxies.
1076
Tim Peters909c0912001-12-14 23:16:18 +00001077Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001078-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001079
Barry Warsaw52acb492001-12-21 20:04:22 +00001080- binascii.b2a_base64(): fix a potential buffer overrun when encoding
1081 very short strings.
1082
1083- cPickle: the obscure "fast" mode was suspected of causing stack
1084 overflows on the Mac. Hopefully fixed this by setting the recursion
1085 limit much smaller. If the limit is too low (it only affects
1086 performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
1087 when compiling cPickle.c (or in pyconfig.h).
1088
Tim Peters909c0912001-12-14 23:16:18 +00001089Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001090-------
Tim Peters909c0912001-12-14 23:16:18 +00001091
Barry Warsaw52acb492001-12-21 20:04:22 +00001092- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
1093 close or delete time).
1094
1095- rfc822.py: fixed a bug where the address '<>' was converted to None
1096 instead of an empty string (also fixes the email.Utils module).
1097
1098- xmlrpclib.py: version 1.0.0; uses precision for doubles.
1099
1100- test suite: the pickle and cPickle tests were not executing any code
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001101 when run from the standard regression test.
Barry Warsaw52acb492001-12-21 20:04:22 +00001102
Tim Peters909c0912001-12-14 23:16:18 +00001103Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001104-----------
Tim Peters909c0912001-12-14 23:16:18 +00001105
1106Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001107-----
Tim Peters909c0912001-12-14 23:16:18 +00001108
1109C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001110-----
Tim Peters909c0912001-12-14 23:16:18 +00001111
1112New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001113-------------
Tim Peters909c0912001-12-14 23:16:18 +00001114
1115Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001116-----
Tim Peters909c0912001-12-14 23:16:18 +00001117
1118Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001119-------
Tim Peters909c0912001-12-14 23:16:18 +00001120
Barry Warsaw52acb492001-12-21 20:04:22 +00001121- distutils package: fixed broken Windows installers (bdist_wininst).
1122
1123- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
1124 instances are deleted at process exit time.
1125
1126- socket.py: prevent mysterious warnings when socket instances are
1127 deleted at process exit time.
1128
1129- posixmodule.c: fix a Windows crash with stat() of a filename ending
1130 in backslash.
1131
Tim Peters909c0912001-12-14 23:16:18 +00001132Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001133----
Tim Peters909c0912001-12-14 23:16:18 +00001134
Barry Warsaw52acb492001-12-21 20:04:22 +00001135- The Carbon toolbox modules have been upgraded to Universal Headers
1136 3.4, and experimental CoreGraphics and CarbonEvents modules have
1137 been added. All only for framework-enabled MacOSX.
1138
Tim Peters909c0912001-12-14 23:16:18 +00001139
Tim Peters6272dfd2001-12-13 19:34:00 +00001140What's New in Python 2.2c1?
Tim Petersb3c9af12001-11-17 00:21:57 +00001141===========================
1142
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001143*Release date: 14-Dec-2001*
1144
Tim Petersb3c9af12001-11-17 00:21:57 +00001145Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001146--------------------------------------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001147
Barry Warsaw06557452001-12-14 20:47:12 +00001148- Guido's tutorial introduction to the new type/class features has
1149 been extensively updated. See
1150
1151 http://www.python.org/2.2/descrintro.html
1152
1153 That remains the primary documentation in this area.
1154
Guido van Rossum33bab012001-12-05 22:45:48 +00001155- Fixed a leak: instance variables declared with __slots__ were never
1156 deleted!
1157
Guido van Rossum4b800852001-12-03 00:54:52 +00001158- The "delete attribute" method of descriptor objects is called
1159 __delete__, not __del__. In previous releases, it was mistakenly
1160 called __del__, which created an unfortunate overloading condition
1161 with finalizers. (The "get attribute" and "set attribute" methods
1162 are still called __get__ and __set__, respectively.)
1163
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001164- Some subtle issues with the super built-in were fixed:
1165
1166 (a) When super itself is subclassed, its __get__ method would still
1167 return an instance of the base class (i.e., of super).
1168
1169 (b) super(C, C()).__class__ would return C rather than super. This
1170 is confusing. To fix this, I decided to change the semantics of
1171 super so that it only applies to code attributes, not to data
1172 attributes. After all, overriding data attributes is not
1173 supported anyway.
1174
1175 (c) The __get__ method didn't check whether the argument was an
1176 instance of the type used in creation of the super instance.
1177
Guido van Rossumcd7b7d62001-12-04 21:02:07 +00001178- Previously, hash() of an instance of a subclass of a mutable type
1179 (list or dictionary) would return some value, rather than raising
1180 TypeError. This has been fixed. Also, directly calling
1181 dict.__hash__ and list.__hash__ now raises the same TypeError
1182 (previously, these were the same as object.__hash__).
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001183
Guido van Rossumd331cb52001-12-05 19:46:42 +00001184- New-style objects now support deleting their __dict__. This is for
1185 all intents and purposes equivalent to assigning a brand new empty
1186 dictionary, but saves space if the object is not used further.
1187
Tim Petersb3c9af12001-11-17 00:21:57 +00001188Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001189-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001190
Tim Peters3caca232001-12-06 06:23:26 +00001191- -Qnew now works as documented in PEP 238: when -Qnew is passed on
1192 the command line, all occurrences of "/" use true division instead
1193 of classic division. See the PEP for details. Note that "all"
1194 means all instances in library and 3rd-party modules, as well as in
1195 your own code. As the PEP says, -Qnew is intended for use only in
1196 educational environments with control over the libraries in use.
Tim Petersbf72fe22001-12-11 21:43:14 +00001197 Note that test_coercion.py in the standard Python test suite fails
1198 under -Qnew; this is expected, and won't be repaired until true
1199 division becomes the default (in the meantime, test_coercion is
1200 testing the current rules).
Tim Peters3caca232001-12-06 06:23:26 +00001201
Fred Drake6c01e252001-12-14 17:08:12 +00001202- complex() now only allows the first argument to be a string
1203 argument, and raises TypeError if either the second arg is a string
1204 or if the second arg is specified when the first is a string.
1205
Tim Petersb3c9af12001-11-17 00:21:57 +00001206Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001207-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001208
Martin v. Löwis560da622001-11-24 09:24:51 +00001209- gc.get_referents was renamed to gc.get_referrers.
1210
Tim Petersb3c9af12001-11-17 00:21:57 +00001211Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001212-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001213
Tim Peters25059d32001-12-07 20:35:43 +00001214- Functions in the os.spawn() family now release the global interpreter
1215 lock around calling the platform spawn. They should always have done
1216 this, but did not before 2.2c1. Multithreaded programs calling
1217 an os.spawn function with P_WAIT will no longer block all Python threads
1218 until the spawned program completes. It's possible that some programs
1219 relies on blocking, although more likely by accident than by design.
1220
Martin v. Löwis3a89b2b2001-11-25 14:35:58 +00001221- webbrowser defaults to netscape.exe on OS/2 now.
1222
Martin v. Löwis652e1912001-11-25 14:50:56 +00001223- Tix.ResizeHandle exposes detach_widget, hide, and show.
1224
Martin v. Löwis714d2e22001-12-02 12:26:03 +00001225- The charset alias windows_1252 has been added.
1226
Barry Warsaw06557452001-12-14 20:47:12 +00001227- types.StringTypes is a tuple containing the defined string types;
1228 usually this will be (str, unicode), but if Python was compiled
1229 without Unicode support it will be just (str,).
1230
1231- The pulldom and minidom modules were synchronized to PyXML.
1232
Tim Petersb3c9af12001-11-17 00:21:57 +00001233Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001234-----------
Tim Petersb3c9af12001-11-17 00:21:57 +00001235
Barry Warsaw06557452001-12-14 20:47:12 +00001236- A new script called Tools/scripts/google.py was added, which fires
1237 off a search on Google.
1238
Tim Petersb3c9af12001-11-17 00:21:57 +00001239Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001240-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001241
Barry Warsaw06557452001-12-14 20:47:12 +00001242- Note that release builds of Python should arrange to define the
1243 preprocessor symbol NDEBUG on the command line (or equivalent).
1244 In the 2.2 pre-release series we tried to define this by magic in
1245 Python.h instead, but it proved to cause problems for extension
1246 authors. The Unix, Windows and Mac builds now all define NDEBUG in
1247 release builds via cmdline (or equivalent) instead. Ports to
1248 other platforms should do likewise.
1249
Jack Jansen1999ef42001-12-06 21:47:20 +00001250- It is no longer necessary to use --with-suffix when building on a
1251 case-insensitive file system (such as Mac OS X HFS+). In the build
1252 directory an extension is used, but not in the installed python.
1253
Tim Petersb3c9af12001-11-17 00:21:57 +00001254C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001255-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001256
Tim Petersf582b822001-12-11 18:51:08 +00001257- New function PyDict_MergeFromSeq2() exposes the builtin dict
1258 constructor's logic for updating a dictionary from an iterable object
1259 producing key-value pairs.
1260
Tim Peterscffed4b2001-11-29 03:26:37 +00001261- PyArg_ParseTupleAndKeywords() requires that the number of entries in
Tim Petersf582b822001-12-11 18:51:08 +00001262 the keyword list equal the number of argument specifiers. This
Tim Peterscffed4b2001-11-29 03:26:37 +00001263 wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
1264 dump core in some bad cases. This has been repaired. As a result,
1265 PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
1266 previously went unchallenged.
1267
Tim Petersb3c9af12001-11-17 00:21:57 +00001268New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001269-------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001270
1271Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001272-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001273
1274Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001275-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001276
1277Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001278----
Tim Petersb3c9af12001-11-17 00:21:57 +00001279
Jack Jansenffa260f2001-12-06 21:14:00 +00001280- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
1281 without any trailing digits.
Tim Petersb3c9af12001-11-17 00:21:57 +00001282
Barry Warsaw06557452001-12-14 20:47:12 +00001283- Changed logic for finding python home in Mac OS X framework Pythons.
1284 Now sys.executable points to the executable again, in stead of to
1285 the shared library. The latter is used only for locating the python
1286 home.
1287
1288
Tim Peters84362bc2001-10-19 17:55:30 +00001289What's New in Python 2.2b2?
Tim Peters84362bc2001-10-19 17:55:30 +00001290===========================
1291
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001292*Release date: 16-Nov-2001*
1293
Tim Peters84362bc2001-10-19 17:55:30 +00001294Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001295--------------------------------------------
Tim Peters84362bc2001-10-19 17:55:30 +00001296
Guido van Rossum3d27df02001-11-15 20:27:54 +00001297- Multiple inheritance mixing new-style and classic classes in the
1298 list of base classes is now allowed, so this works now:
Tim Peters76f7fe32001-11-15 20:02:21 +00001299
1300 class Classic: pass
Guido van Rossum3d27df02001-11-15 20:27:54 +00001301 class Mixed(Classic, object): pass
Tim Peters76f7fe32001-11-15 20:02:21 +00001302
1303 The MRO (method resolution order) for each base class is respected
1304 according to its kind, but the MRO for the derived class is computed
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001305 using new-style MRO rules if any base class is a new-style class.
Tim Peters76f7fe32001-11-15 20:02:21 +00001306 This needs to be documented.
1307
Tim Petersa427a2b2001-10-29 22:25:45 +00001308- The new builtin dictionary() constructor, and dictionary type, have
1309 been renamed to dict. This reflects a decade of common usage.
1310
Guido van Rossum3fc08d22001-11-15 20:33:10 +00001311- dict() now accepts an iterable object producing 2-sequences. For
1312 example, dict(d.items()) == d for any dictionary d. The argument,
1313 and the elements of the argument, can be any iterable objects.
1314
Guido van Rossum7ad2d1e2001-10-29 22:11:00 +00001315- New-style classes can now have a __del__ method, which is called
1316 when the instance is deleted (just like for classic classes).
1317
Guido van Rossum12d955c2001-10-26 14:56:06 +00001318- Assignment to object.__dict__ is now possible, for objects that are
1319 instances of new-style classes that have a __dict__ (unless the base
1320 class forbids it).
1321
Guido van Rossumc8e56452001-10-22 00:43:43 +00001322- Methods of built-in types now properly check for keyword arguments
1323 (formerly these were silently ignored). The only built-in methods
1324 that take keyword arguments are __call__, __init__ and __new__.
1325
Guido van Rossum86443212001-10-27 22:28:54 +00001326- The socket function has been converted to a type; see below.
1327
Tim Peters84362bc2001-10-19 17:55:30 +00001328Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001329-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001330
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001331- Assignment to __debug__ raises SyntaxError at compile-time. This
1332 was promised when 2.1c1 was released as "What's New in Python 2.1c1"
Barry Warsaw012852b2001-11-16 16:17:27 +00001333 (see below) says.
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001334
Guido van Rossum12d955c2001-10-26 14:56:06 +00001335- Clarified the error messages for unsupported operands to an operator
1336 (like 1 + '').
1337
Tim Peters84362bc2001-10-19 17:55:30 +00001338Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001339-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001340
Tim Peters5ebfd362001-11-13 23:11:19 +00001341- mmap has a new keyword argument, "access", allowing a uniform way for
1342 both Windows and Unix users to create read-only, write-through and
1343 copy-on-write memory mappings. This was previously possible only on
1344 Unix. A new keyword argument was required to support this in a
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001345 uniform way because the mmap() signatures had diverged across
Tim Peters5ebfd362001-11-13 23:11:19 +00001346 platforms. Thanks to Jay T Miller for repairing this!
1347
Tim Peters169ded02001-11-03 19:57:21 +00001348- By default, the gc.garbage list now contains only those instances in
1349 unreachable cycles that have __del__ methods; in 2.1 it contained all
1350 instances in unreachable cycles. "Instances" here has been generalized
1351 to include instances of both new-style and old-style classes.
1352
Guido van Rossum12d955c2001-10-26 14:56:06 +00001353- The socket module defines a new method for socket objects,
1354 sendall(). This is like send() but may make multiple calls to
Guido van Rossum86443212001-10-27 22:28:54 +00001355 send() until all data has been sent. Also, the socket function has
1356 been converted to a subclassable type, like list and tuple (etc.)
1357 before it; socket and SocketType are now the same thing.
Guido van Rossum12d955c2001-10-26 14:56:06 +00001358
1359- Various bugfixes to the curses module. There is now a test suite
1360 for the curses module (you have to run it manually).
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001361
Guido van Rossum692adf12001-10-30 03:03:03 +00001362- binascii.b2a_base64 no longer places an arbitrary restriction of 57
1363 bytes on its input.
1364
Tim Peters84362bc2001-10-19 17:55:30 +00001365Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001366-------
Tim Peters84362bc2001-10-19 17:55:30 +00001367
Tim Peters5ebfd362001-11-13 23:11:19 +00001368- tkFileDialog exposes a Directory class and askdirectory
Martin v. Löwis25ee87c2001-11-07 22:38:08 +00001369 convenience function.
1370
Tim Peters75335872001-11-03 19:35:43 +00001371- Symbolic group names in regular expressions must be unique. For
1372 example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
1373 single name can't mean both "group 1" and "group 2" simultaneously.
Barry Warsaw012852b2001-11-16 16:17:27 +00001374 Python 2.2 detects this error at regexp compilation time;
1375 previously, the error went undetected, and results were
1376 unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
1377 pattern.subn() methods have been rewritten in C. Also, an
1378 experimental function/method finditer() has been added, which works
1379 like findall() but returns an iterator.
Tim Peters75335872001-11-03 19:35:43 +00001380
Martin v. Löwisb7b32602001-11-02 23:48:20 +00001381- Tix exposes more commands through the classes DirSelectBox,
1382 DirSelectDialog, ListNoteBook, Meter, CheckList, and the
1383 methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
1384 tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
1385
Tim Peters98791af2001-10-23 01:59:54 +00001386- Traceback objects are now scanned by cyclic garbage collection, so
1387 cycles created by casual use of sys.exc_info() no longer cause
1388 permanent memory leaks (provided garbage collection is enabled).
1389
Guido van Rossum49192142001-10-24 20:51:44 +00001390- os.extsep -- a new variable needed by the RISCOS support. It is the
1391 separator used by extensions, and is '.' on all platforms except
1392 RISCOS, where it is '/'. There is no need to use this variable
1393 unless you have a masochistic desire to port your code to RISCOS.
1394
Barry Warsaw012852b2001-11-16 16:17:27 +00001395- mimetypes.py has optional support for non-standard, but commonly
1396 found types. guess_type() and guess_extension() now accept an
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001397 optional 'strict' flag, defaulting to true, which controls whether
Barry Warsaw012852b2001-11-16 16:17:27 +00001398 recognize non-standard types or not. A few non-standard types we
1399 know about have been added. Also, when run as a script, there are
1400 new -l and -e options.
1401
1402- statcache is now deprecated.
1403
1404- email.Utils.formatdate() now produces the preferred RFC 2822 style
1405 dates with numeric timezones (it used to produce obsolete dates
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001406 hard coded to "GMT" timezone). An optional 'localtime' flag is
Barry Warsaw012852b2001-11-16 16:17:27 +00001407 added to produce dates in the local timezone, with daylight savings
1408 time properly taken into account.
1409
1410- In pickle and cPickle, instead of masking errors in load() by
1411 transforming them into SystemError, we let the original exception
1412 propagate out. Also, implement support for __safe_for_unpickling__
1413 in pickle, as it already was supported in cPickle.
1414
Tim Peters84362bc2001-10-19 17:55:30 +00001415Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001416-----------
Tim Peters84362bc2001-10-19 17:55:30 +00001417
1418Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001419-----
Tim Peters84362bc2001-10-19 17:55:30 +00001420
Barry Warsaw012852b2001-11-16 16:17:27 +00001421- The dbm module is built using libdb1 if available. The bsddb module
1422 is built with libdb3 if available.
1423
1424- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
1425
Tim Peters84362bc2001-10-19 17:55:30 +00001426C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001427-----
Tim Peters84362bc2001-10-19 17:55:30 +00001428
Tim Peters1fc240e2001-10-26 05:06:50 +00001429- New function PySequence_Fast_GET_SIZE() returns the size of a non-
1430 NULL result from PySequence_Fast(), more quickly than calling
1431 PySequence_Size().
1432
Barry Warsaw012852b2001-11-16 16:17:27 +00001433- New argument unpacking function PyArg_UnpackTuple() added.
1434
1435- New functions PyObject_CallFunctionObjArgs() and
1436 PyObject_CallMethodObjArgs() have been added to make it more
1437 convenient and efficient to call functions and methods from C.
1438
1439- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
1440 possible that this will propagate errors it didn't before.
1441
1442- New function PyObject_CheckReadBuffer(), which returns true if its
1443 argument supports the single-segment readable buffer interface.
1444
Tim Peters84362bc2001-10-19 17:55:30 +00001445New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001446-------------
Tim Peters84362bc2001-10-19 17:55:30 +00001447
Guido van Rossum86443212001-10-27 22:28:54 +00001448- We've finally confirmed that this release builds on HP-UX 11.00,
1449 *with* threads, and passes the test suite.
1450
Tim Peters7a33d8b2001-11-05 02:51:07 +00001451- Thanks to a series of patches from Michael Muller, Python may build
1452 again under OS/2 Visual Age C++.
1453
Guido van Rossum49192142001-10-24 20:51:44 +00001454- Updated RISCOS port by Dietmar Schwertberger.
1455
Tim Peters84362bc2001-10-19 17:55:30 +00001456Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001457-----
Tim Peters84362bc2001-10-19 17:55:30 +00001458
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001459- Added a test script for the curses module. It isn't run automatically;
1460 regrtest.py must be run with '-u curses' to enable it.
1461
Tim Peters84362bc2001-10-19 17:55:30 +00001462Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001463-------
Tim Peters84362bc2001-10-19 17:55:30 +00001464
Barry Warsaw012852b2001-11-16 16:17:27 +00001465Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001466----
Barry Warsaw012852b2001-11-16 16:17:27 +00001467
1468- PythonScript has been moved to unsupported and is slated to be
1469 removed completely in the next release.
1470
1471- It should now be possible to build applets that work on both OS9 and
1472 OSX.
1473
1474- The core is now linked with CoreServices not Carbon; as a side
1475 result, default 8bit encoding on OSX is now ASCII.
1476
1477- Python should now build on OSX 10.1.1
1478
Tim Peters84362bc2001-10-19 17:55:30 +00001479
Tim Petersabf925f2001-09-28 21:53:42 +00001480What's New in Python 2.2b1?
Tim Petersabf925f2001-09-28 21:53:42 +00001481===========================
1482
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001483*Release date: 19-Oct-2001*
1484
Tim Petersabf925f2001-09-28 21:53:42 +00001485Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001486--------------------------------------------
Tim Petersabf925f2001-09-28 21:53:42 +00001487
Guido van Rossum687ae002001-10-15 22:03:32 +00001488- New-style classes are now always dynamic (except for built-in and
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001489 extension types). There is no longer a performance penalty, and I
Guido van Rossum687ae002001-10-15 22:03:32 +00001490 no longer see another reason to keep this baggage around. One relic
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001491 remains: the __dict__ of a new-style class is a read-only proxy; you
1492 must set the class's attribute to modify it. As a consequence, the
Guido van Rossum687ae002001-10-15 22:03:32 +00001493 __defined__ attribute of new-style types no longer exists, for lack
1494 of need: there is once again only one __dict__ (although in the
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001495 future a __cache__ may be resurrected with a similar function, if I
1496 can prove that it actually speeds things up).
Guido van Rossum50fda3b2001-10-04 19:46:06 +00001497
Tim Peters1c9ca872001-10-04 06:43:12 +00001498- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
1499 always returned None, even when there was a class docstring).
1500
1501- doctest now finds and runs docstrings attached to new-style classes,
1502 class methods, static methods, and properties.
1503
Guido van Rossum9074ef62001-10-16 21:34:49 +00001504Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001505-----------------
Tim Petersabf925f2001-09-28 21:53:42 +00001506
Guido van Rossuma8bcf802001-10-15 15:53:58 +00001507- A very subtle syntactical pitfall in list comprehensions was fixed.
1508 For example: [a+b for a in 'abc', for b in 'def']. The comma in
1509 this example is a mistake. Previously, this would silently let 'a'
1510 iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
1511 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
1512 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
1513 Note that [a for a in <singleton>] is a convoluted way to say
1514 [<singleton>] anyway, so it's not like any expressiveness is lost.
1515
Guido van Rossum9074ef62001-10-16 21:34:49 +00001516- getattr(obj, name, default) now only catches AttributeError, as
1517 documented, rather than returning the default value for all
1518 exceptions (which could mask bugs in a __getattr__ hook, for
1519 example).
1520
Fred Drakecb7a6b52001-10-22 18:41:51 +00001521- Weak reference objects are now part of the core and offer a C API.
Fred Drake934d2a42001-10-18 18:18:06 +00001522 A bug which could allow a core dump when binary operations involved
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001523 proxy reference has been fixed. weakref.ReferenceError is now a
Barry Warsawf6fb1712001-10-19 05:35:40 +00001524 built-in exception.
Fred Drake934d2a42001-10-18 18:18:06 +00001525
Guido van Rossum1c486092001-10-19 02:05:35 +00001526- unicode(obj) now behaves more like str(obj), accepting arbitrary
1527 objects, and calling a __unicode__ method if it exists.
1528 unicode(obj, encoding) and unicode(obj, encoding, errors) still
Marc-André Lemburgb5507ec2001-10-19 12:02:29 +00001529 require an 8-bit string or character buffer argument.
Guido van Rossum1c486092001-10-19 02:05:35 +00001530
Barry Warsawf6fb1712001-10-19 05:35:40 +00001531- isinstance() now allows any object as the first argument and a
1532 class, a type or something with a __bases__ tuple attribute for the
1533 second argument. The second argument may also be a tuple of a
1534 class, type, or something with __bases__, in which case isinstance()
1535 will return true if the first argument is an instance of any of the
1536 things contained in the second argument tuple. E.g.
1537
1538 isinstance(x, (A, B))
1539
1540 returns true if x is an instance of A or B.
1541
Guido van Rossum9074ef62001-10-16 21:34:49 +00001542Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001543-----------------
Guido van Rossum9074ef62001-10-16 21:34:49 +00001544
1545- thread.start_new_thread() now returns the thread ID (previously None).
1546
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001547- binascii has now two quopri support functions, a2b_qp and b2a_qp.
1548
Guido van Rossumc524d952001-10-19 01:31:59 +00001549- readline now supports setting the startup_hook and the
1550 pre_event_hook, and adds the add_history() function.
Martin v. Löwis0daad592001-09-30 21:09:59 +00001551
Guido van Rossumc524d952001-10-19 01:31:59 +00001552- os and posix supports chroot(), setgroups() and unsetenv() where
1553 available. The stat(), fstat(), statvfs() and fstatvfs() functions
1554 now return "pseudo-sequences" -- the various fields can now be
1555 accessed as attributes (e.g. os.stat("/").st_mtime) but for
1556 backwards compatibility they also behave as a fixed-length sequence.
1557 Some platform-specific fields (e.g. st_rdev) are only accessible as
Guido van Rossum98bf58f2001-10-18 20:34:25 +00001558 attributes.
1559
1560- time: localtime(), gmtime() and strptime() now return a
1561 pseudo-sequence similar to the os.stat() return value, with
1562 attributes like tm_year etc.
Martin v. Löwis16628c92001-10-04 22:46:41 +00001563
Guido van Rossum9074ef62001-10-16 21:34:49 +00001564- Decompression objects in the zlib module now accept an optional
1565 second parameter to decompress() that specifies the maximum amount
1566 of memory to use for the uncompressed data.
Tim Petersabf925f2001-09-28 21:53:42 +00001567
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001568- optional SSL support in the socket module now exports OpenSSL
1569 functions RAND_add(), RAND_egd(), and RAND_status(). These calls
1570 are useful on platforms like Solaris where OpenSSL does not
Barry Warsawf6fb1712001-10-19 05:35:40 +00001571 automatically seed its PRNG. Also, the keyfile and certfile
1572 arguments to socket.ssl() are now optional.
1573
1574- posixmodule (and by extension, the os module on POSIX platforms) now
1575 exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001576
Guido van Rossum9074ef62001-10-16 21:34:49 +00001577Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001578-------
Guido van Rossum3c288632001-10-16 21:13:49 +00001579
Tim Peters7402f792001-10-02 03:53:41 +00001580- doctest now excludes functions and classes not defined by the module
1581 being tested, thanks to Tim Hochberg.
1582
Fred Drakecb7a6b52001-10-22 18:41:51 +00001583- HotShot, a new profiler implemented using a C-based callback, has
1584 been added. This substantially reduces the overhead of profiling,
1585 but it is still quite preliminary. Support modules and
1586 documentation will be added in upcoming releases (before 2.2 final).
1587
Guido van Rossumc4b09b42001-10-04 10:19:00 +00001588- profile now produces correct output in situations where an exception
1589 raised in Python is cleared by C code (e.g. hasattr()). This used
1590 to cause wrong output, including spurious claims of recursive
1591 functions and attribution of time spent to the wrong function.
1592
Tim Peters0a1fc4e2001-10-07 03:12:08 +00001593 The code and documentation for the derived OldProfile and HotProfile
1594 profiling classes was removed. The code hasn't worked for years (if
1595 you tried to use them, they raised exceptions). OldProfile
1596 intended to reproduce the behavior of the profiler Python used more
1597 than 7 years ago, and isn't interesting anymore. HotProfile intended
1598 to provide a faster profiler (but producing less information), and
1599 that's a worthy goal we intend to meet via a different approach (but
1600 without losing information).
1601
Tim Peterscce092d2001-10-09 05:31:56 +00001602- Profile.calibrate() has a new implementation that should deliver
Tim Peters659a6032001-10-09 20:51:19 +00001603 a much better system-specific calibration constant. The constant can
1604 now be specified in an instance constructor, or as a Profile class or
1605 instance variable, instead of by editing profile.py's source code.
1606 Calibration must still be done manually (see the docs for the profile
1607 module).
1608
1609 Note that Profile.calibrate() must be overriden by subclasses.
1610 Improving the accuracy required exploiting detailed knowledge of
1611 profiler internals; the earlier method abstracted away the details
1612 and measured a simplified model instead, but consequently computed
1613 a constant too small by a factor of 2 on some modern machines.
Tim Peterscce092d2001-10-09 05:31:56 +00001614
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001615- quopri's encode and decode methods take an optional header parameter,
Jeremy Hylton6f543b62001-10-16 20:42:52 +00001616 which indicates whether output is intended for the header 'Q'
1617 encoding.
1618
Guido van Rossuma5343cc2001-10-18 18:02:07 +00001619- The SocketServer.ThreadingMixIn class now closes the request after
1620 finish_request() returns. (Not when it errors out though.)
1621
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001622- The nntplib module's NNTP.body() method has grown a 'file' argument
Barry Warsawf6fb1712001-10-19 05:35:40 +00001623 to allow saving the message body to a file.
1624
1625- The email package has added a class email.Parser.HeaderParser which
1626 only parses headers and does not recurse into the message's body.
1627 Also, the module/class MIMEAudio has been added for representing
1628 audio data (contributed by Anthony Baxter).
1629
1630- ftplib should be able to handle files > 2GB.
1631
1632- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
1633 ON, and OFF.
1634
Fred Drakecb7a6b52001-10-22 18:41:51 +00001635- xml.dom.minidom NodeList objects now support the length attribute
1636 and item() method as required by the DOM specifications.
1637
Guido van Rossumed554f62001-10-02 23:15:37 +00001638Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001639-----------
Guido van Rossumed554f62001-10-02 23:15:37 +00001640
1641- Demo/dns was removed. It no longer serves any purpose; a package
1642 derived from it is now maintained by Anthony Baxter, see
1643 http://PyDNS.SourceForge.net.
Tim Petersabf925f2001-09-28 21:53:42 +00001644
Barry Warsawf6fb1712001-10-19 05:35:40 +00001645- The freeze tool has been made more robust, and two new options have
1646 been added: -X and -E.
1647
Tim Petersabf925f2001-09-28 21:53:42 +00001648Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001649-----
Tim Petersabf925f2001-09-28 21:53:42 +00001650
Barry Warsawf6fb1712001-10-19 05:35:40 +00001651- configure will use CXX in LINKCC if CXX is used to build main() and
1652 the system requires to link a C++ main using the C++ compiler.
1653
Tim Petersabf925f2001-09-28 21:53:42 +00001654C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001655-----
Tim Petersabf925f2001-09-28 21:53:42 +00001656
Guido van Rossum6c4bce32001-10-18 19:20:25 +00001657- The documentation for the tp_compare slot is updated to require that
1658 the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
1659 not correct. This is not yet enforced but will be enforced in
1660 Python 2.3; even later, we may use -2 to indicate errors and +2 for
1661 "NotImplemented". Right now, -1 should be used for an error return.
1662
Tim Petersd38b1c72001-09-30 05:09:37 +00001663- PyLong_AsLongLong() now accepts int (as well as long) arguments.
1664 Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
1665 as long) arguments.
1666
Guido van Rossum3c288632001-10-16 21:13:49 +00001667- PyThread_start_new_thread() now returns a long int giving the thread
1668 ID, if one can be calculated; it returns -1 for error, 0 if no
1669 thread ID is calculated (this is an incompatible change, but only
1670 the thread module used this API). This code has only really been
1671 tested on Linux and Windows; other platforms please beware (and
1672 report any bugs or strange behavior).
1673
Guido van Rossum1c486092001-10-19 02:05:35 +00001674- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
1675 input.
1676
Tim Petersabf925f2001-09-28 21:53:42 +00001677New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001678-------------
Tim Petersabf925f2001-09-28 21:53:42 +00001679
1680Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001681-----
Tim Petersabf925f2001-09-28 21:53:42 +00001682
1683Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001684-------
Tim Petersabf925f2001-09-28 21:53:42 +00001685
Tim Peters04cf1d32001-10-09 22:39:40 +00001686- Installer: If you install IDLE, and don't disable file-extension
1687 registration, a new "Edit with IDLE" context (right-click) menu entry
1688 is created for .py and .pyw files.
1689
Tim Peters1ce3cf72001-10-01 17:58:40 +00001690- The signal module now supports SIGBREAK on Windows, thanks to Steven
1691 Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
1692 action remains to call Win32 ExitProcess(). This can be changed via
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00001693 signal.signal(). For example::
Tim Peters1ce3cf72001-10-01 17:58:40 +00001694
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001695 # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
1696 # (SIGINT) behavior.
1697 import signal
1698 signal.signal(signal.SIGBREAK, signal.default_int_handler)
Tim Peters1ce3cf72001-10-01 17:58:40 +00001699
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001700 try:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001701 while 1:
1702 pass
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001703 except KeyboardInterrupt:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001704 # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
1705 # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
1706 # program without the possibility for any Python-level cleanup).
1707 print "Clean exit"
Tim Peters1ce3cf72001-10-01 17:58:40 +00001708
Tim Petersabf925f2001-09-28 21:53:42 +00001709
Tim Petersb07352e2001-09-08 01:25:47 +00001710What's New in Python 2.2a4?
1711===========================
1712
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001713*Release date: 28-Sep-2001*
1714
Guido van Rossum808eea72001-09-25 04:15:41 +00001715Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001716--------------------------------------------
Guido van Rossum808eea72001-09-25 04:15:41 +00001717
1718- pydoc and inspect are now aware of new-style classes;
1719 e.g. help(list) at the interactive prompt now shows proper
1720 documentation for all operations on list objects.
1721
1722- Applications using Jim Fulton's ExtensionClass module can now safely
1723 be used with Python 2.2. In particular, Zope 2.4.1 now works with
1724 Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
1725 examples also work again. It is hoped that Gtk and Boost also work
1726 with 2.2a4 and beyond. (If you can confirm this, please write
1727 webmaster@python.org; if there are still problems, please open a bug
1728 report on SourceForge.)
Tim Petersb07352e2001-09-08 01:25:47 +00001729
Tim Peters66c1a522001-09-24 21:17:50 +00001730- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001731 These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
Tim Peters66c1a522001-09-24 21:17:50 +00001732 in the constructed property object. fget, fset and fdel weren't
1733 discoverable from Python in 2.2a3. __doc__ is new, and allows to
1734 associate a docstring with a property.
1735
Guido van Rossum808eea72001-09-25 04:15:41 +00001736- Comparison overloading is now more completely implemented. For
1737 example, a str subclass instance can properly be compared to a str
1738 instance, and it can properly overload comparison. Ditto for most
1739 other built-in object types.
1740
1741- The repr() of new-style classes has changed; instead of <type
1742 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
1743 *except* for built-in types, which are still rendered as <type
1744 'Foo'> (to avoid upsetting existing code that might parse or
1745 otherwise rely on repr() of certain type objects).
1746
1747- The repr() of new-style objects is now always <Foo object at XXX>;
1748 previously, it was sometimes <Foo instance at XXX>.
1749
1750- For new-style classes, what was previously called __getattr__ is now
1751 called __getattribute__. This method, if defined, is called for
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001752 *every* attribute access. A new __getattr__ hook more similar to the
Guido van Rossum808eea72001-09-25 04:15:41 +00001753 one in classic classes is defined which is called only if regular
1754 attribute access raises AttributeError; to catch *all* attribute
1755 access, you can use __getattribute__ (for new-style classes). If
1756 both are defined, __getattribute__ is called first, and if it raises
1757 AttributeError, __getattr__ is called.
1758
1759- The __class__ attribute of new-style objects can be assigned to.
1760 The new class must have the same C-level object layout as the old
1761 class.
1762
1763- The builtin file type can be subclassed now. In the usual pattern,
1764 "file" is the name of the builtin type, and file() is a new builtin
1765 constructor, with the same signature as the builtin open() function.
1766 file() is now the preferred way to open a file.
1767
1768- Previously, __new__ would only see sequential arguments passed to
1769 the type in a constructor call; __init__ would see both sequential
1770 and keyword arguments. This made no sense whatsoever any more, so
1771 now both __new__ and __init__ see all arguments.
1772
1773- Previously, hash() applied to an instance of a subclass of str or
1774 unicode always returned 0. This has been repaired.
1775
1776- Previously, an operation on an instance of a subclass of an
1777 immutable type (int, long, float, complex, tuple, str, unicode),
1778 where the subtype didn't override the operation (and so the
1779 operation was handled by the builtin type), could return that
1780 instance instead a value of the base type. For example, if s was of
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001781 a str subclass type, s[:] returned s as-is. Now it returns a str
Guido van Rossum808eea72001-09-25 04:15:41 +00001782 with the same value as s.
1783
Barry Warsaw86fbaf82001-09-28 15:26:12 +00001784- Provisional support for pickling new-style objects has been added.
1785
Guido van Rossum808eea72001-09-25 04:15:41 +00001786Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001787----
Guido van Rossum808eea72001-09-25 04:15:41 +00001788
Tim Peters2c9aa5e2001-09-23 04:06:05 +00001789- file.writelines() now accepts any iterable object producing strings.
1790
Marc-André Lemburgaefd7662001-09-20 12:59:37 +00001791- PyUnicode_FromEncodedObject() now works very much like
1792 PyObject_Str(obj) in that it tries to use __str__/tp_str
1793 on the object if the object is not a string or buffer. This
1794 makes unicode() behave like str() when applied to non-string/buffer
1795 objects.
1796
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001797- PyFile_WriteObject now passes Unicode objects to the file's write
1798 method. As a result, all file-like objects which may be the target
Martin v. Löwis2777c022001-09-19 13:47:32 +00001799 of a print statement must support Unicode objects, i.e. they must
1800 at least convert them into ASCII strings.
1801
Guido van Rossum624c8af2001-09-18 15:21:04 +00001802- Thread scheduling on Solaris should be improved; it is no longer
1803 necessary to insert a small sleep at the start of a thread in order
1804 to let other runnable threads be scheduled.
1805
Tim Petersb07352e2001-09-08 01:25:47 +00001806Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001807-------
Tim Petersb07352e2001-09-08 01:25:47 +00001808
Marc-André Lemburgbf990172001-09-27 14:17:33 +00001809- StringIO.StringIO instances and cStringIO.StringIO instances support
1810 read character buffer compatible objects for their .write() methods.
1811 These objects are converted to strings and then handled as such
1812 by the instances.
1813
Barry Warsaw2f600732001-09-24 04:28:10 +00001814- The "email" package has been added. This is basically a port of the
1815 mimelib package <http://sf.net/projects/mimelib> with API changes
1816 and some implementations updated to use iterators and generators.
1817
Tim Peters8a9c2842001-09-22 21:30:22 +00001818- difflib.ndiff() and difflib.Differ.compare() are generators now. This
1819 restores the ability of Tools/scripts/ndiff.py to start producing output
1820 before the entire comparison is complete.
1821
Barry Warsaw58b072d2001-09-22 04:44:21 +00001822- StringIO.StringIO instances and cStringIO.StringIO instances support
1823 iteration just like file objects (i.e. their .readline() method is
1824 called for each iteration until it returns an empty string).
1825
Marc-André Lemburg494f2ae2001-09-19 11:33:31 +00001826- The codecs module has grown four new helper APIs to access
1827 builtin codecs: getencoder(), getdecoder(), getreader(),
1828 getwriter().
1829
Guido van Rossum624c8af2001-09-18 15:21:04 +00001830- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
1831 simplifies writing XML RPC servers.
1832
Barry Warsaw647d5e82001-09-28 17:01:02 +00001833- os.path.realpath(): a new function that returns the absolute pathname
Guido van Rossum624c8af2001-09-18 15:21:04 +00001834 after interpretation of symbolic links. On non-Unix systems, this
1835 is an alias for os.path.abspath().
1836
Tim Peters16a77ad2001-09-08 04:00:12 +00001837- operator.indexOf() (PySequence_Index() in the C API) now works with any
1838 iterable object.
1839
Guido van Rossum624c8af2001-09-18 15:21:04 +00001840- smtplib now supports various authentication and security features of
1841 the SMTP protocol through the new login() and starttls() methods.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00001842
Guido van Rossum624c8af2001-09-18 15:21:04 +00001843- hmac: a new module implementing keyed hashing for message
1844 authentication.
1845
1846- mimetypes now recognizes more extensions and file types. At the
1847 same time, some mappings not sanctioned by IANA were removed.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00001848
Guido van Rossum624c8af2001-09-18 15:21:04 +00001849- The "compiler" package has been brought up to date to the state of
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00001850 Python 2.2 bytecode generation. It has also been promoted from a
1851 Tool to a standard library package. (Tools/compiler still exists as
1852 a sample driver.)
1853
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00001854Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001855-----
Guido van Rossum624c8af2001-09-18 15:21:04 +00001856
Tim Petersb07352e2001-09-08 01:25:47 +00001857Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001858-----
Tim Petersb07352e2001-09-08 01:25:47 +00001859
Guido van Rossum624c8af2001-09-18 15:21:04 +00001860- Large file support (LFS) is now automatic when the platform supports
1861 it; no more manual configuration tweaks are needed. On Linux, at
1862 least, it's possible to have a system whose C library supports large
1863 files but whose kernel doesn't; in this case, large file support is
1864 still enabled but doesn't do you any good unless you upgrade your
1865 kernel or share your Python executable with another system whose
1866 kernel has large file support.
1867
1868- The configure script now supplies plausible defaults in a
1869 cross-compilation environment. This doesn't mean that the supplied
1870 values are always correct, or that cross-compilation now works
1871 flawlessly -- but it's a first step (and it shuts up most of
1872 autoconf's warnings about AC_TRY_RUN).
1873
1874- The Unix build is now a bit less chatty, courtesy of the parser
1875 generator. The build is completely silent (except for errors) when
1876 using "make -s", thanks to a -q option to setup.py.
1877
Tim Petersb07352e2001-09-08 01:25:47 +00001878C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001879-----
Tim Petersb07352e2001-09-08 01:25:47 +00001880
Guido van Rossum624c8af2001-09-18 15:21:04 +00001881- The "structmember" API now supports some new flag bits to deny read
1882 and/or write access to attributes in restricted execution mode.
1883
Tim Petersb07352e2001-09-08 01:25:47 +00001884New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001885-------------
Tim Petersb07352e2001-09-08 01:25:47 +00001886
Guido van Rossum624c8af2001-09-18 15:21:04 +00001887- Compaq's iPAQ handheld, running the "familiar" Linux distribution
1888 (http://familiar.handhelds.org).
1889
Tim Petersb07352e2001-09-08 01:25:47 +00001890Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001891-----
Tim Petersb07352e2001-09-08 01:25:47 +00001892
Tim Peters8a9c2842001-09-22 21:30:22 +00001893- The "classic" standard tests, which work by comparing stdout to
1894 an expected-output file under Lib/test/output/, no longer stop at
1895 the first mismatch. Instead the test is run to completion, and a
1896 variant of ndiff-style comparison is used to report all differences.
1897 This is much easier to understand than the previous style of reporting.
1898
1899- The unittest-based standard tests now use regrtest's test_main()
1900 convention, instead of running as a side-effect of merely being
1901 imported. This allows these tests to be run in more natural and
1902 flexible ways as unittests, outside the regrtest framework.
1903
1904- regrtest.py is much better integrated with unittest and doctest now,
1905 especially in regard to reporting errors.
1906
Tim Petersb07352e2001-09-08 01:25:47 +00001907Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001908-------
Tim Petersb07352e2001-09-08 01:25:47 +00001909
Guido van Rossum624c8af2001-09-18 15:21:04 +00001910- Large file support now also works for files > 4GB, on filesystems
Tim Peters8a9c2842001-09-22 21:30:22 +00001911 that support it (NTFS under Windows 2000). See "What's New in
1912 Python 2.2a3" for more detail.
Guido van Rossum624c8af2001-09-18 15:21:04 +00001913
Tim Petersb07352e2001-09-08 01:25:47 +00001914
Tim Petersedc99312001-08-22 21:36:50 +00001915What's New in Python 2.2a3?
1916===========================
1917
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001918*Release Date: 07-Sep-2001*
1919
Tim Petersedc99312001-08-22 21:36:50 +00001920Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001921----
Tim Petersedc99312001-08-22 21:36:50 +00001922
Tim Peters9fffa3e2001-09-04 05:14:19 +00001923- Conversion of long to float now raises OverflowError if the long is too
1924 big to represent as a C double.
1925
Tim Peters32f453e2001-09-03 08:35:41 +00001926- The 3-argument builtin pow() no longer allows a third non-None argument
1927 if either of the first two arguments is a float, or if both are of
1928 integer types and the second argument is negative (in which latter case
1929 the arguments are converted to float, so this is really the same
1930 restriction).
1931
Tim Peters5d2b77c2001-09-03 05:47:38 +00001932- The builtin dir() now returns more information, and sometimes much
1933 more, generally naming all attributes of an object, and all attributes
1934 reachable from the object via its class, and from its class's base
1935 classes, and so on from them too. Example: in 2.2a2, dir([]) returned
1936 an empty list. In 2.2a3,
1937
1938 >>> dir([])
1939 ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
1940 '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
1941 '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
1942 '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
1943 '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
1944 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
1945 'reverse', 'sort']
1946
1947 dir(module) continues to return only the module's attributes, though.
1948
Tim Petersbdee63f2001-09-02 03:40:59 +00001949- Overflowing operations on plain ints now return a long int rather
Guido van Rossumae457142001-08-31 18:31:35 +00001950 than raising OverflowError. This is a partial implementation of PEP
1951 237. You can use -Wdefault::OverflowWarning to enable a warning for
1952 this situation, and -Werror::OverflowWarning to revert to the old
1953 OverflowError exception.
1954
Guido van Rossum61c345f2001-09-04 03:26:15 +00001955- A new command line option, -Q<arg>, is added to control run-time
Guido van Rossumae457142001-08-31 18:31:35 +00001956 warnings for the use of classic division. (See PEP 238.) Possible
Barry Warsawd6c8ca62001-09-07 18:13:44 +00001957 values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
1958 -Qold, meaning the / operator has its classic meaning and no
1959 warnings are issued. Using -Qwarn issues a run-time warning about
1960 all uses of classic division for int and long arguments; -Qwarnall
1961 also warns about classic division for float and complex arguments
Tim Peters3caca232001-12-06 06:23:26 +00001962 (for use with fixdiv.py).
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001963 [Note: the remainder of this item (preserved below) became
1964 obsolete in 2.2c1 -- -Qnew has global effect in 2.2] ::
1965
1966 Using -Qnew is questionable; it turns on new division by default, but
1967 only in the __main__ module. You can usefully combine -Qwarn or
1968 -Qwarnall and -Qnew: this gives the __main__ module new division, and
1969 warns about classic division everywhere else.
Guido van Rossumae457142001-08-31 18:31:35 +00001970
Tim Petersbdee63f2001-09-02 03:40:59 +00001971- Many built-in types can now be subclassed. This applies to int,
Guido van Rossumae457142001-08-31 18:31:35 +00001972 long, float, str, unicode, and tuple. (The types complex, list and
1973 dictionary can also be subclassed; this was introduced earlier.)
1974 Note that restrictions apply when subclassing immutable built-in
1975 types: you can only affect the value of the instance by overloading
1976 __new__. You can add mutable attributes, and the subclass instances
1977 will have a __dict__ attribute, but you cannot change the "value"
1978 (as implemented by the base class) of an immutable subclass instance
1979 once it is created.
1980
Guido van Rossumaaf80c82001-09-02 13:44:35 +00001981- The dictionary constructor now takes an optional argument, a
1982 mapping-like object, and initializes the dictionary from its
1983 (key, value) pairs.
1984
Tim Petersbdee63f2001-09-02 03:40:59 +00001985- A new built-in type, super, has been added. This facilitates making
Guido van Rossumae457142001-08-31 18:31:35 +00001986 "cooperative super calls" in a multiple inheritance setting. For an
1987 explanation, see http://www.python.org/2.2/descrintro.html#cooperation
1988
Guido van Rossum8d7234d2001-09-06 22:02:58 +00001989- A new built-in type, property, has been added. This enables the
1990 creation of "properties". These are attributes implemented by
1991 getter and setter functions (or only one of these for read-only or
1992 write-only attributes), without the need to override __getattr__.
1993 See http://www.python.org/2.2/descrintro.html#property
Guido van Rossumae457142001-08-31 18:31:35 +00001994
Tim Petersbdee63f2001-09-02 03:40:59 +00001995- The syntax of floating-point and imaginary literals has been
Tim Petersd507dab2001-08-30 20:51:59 +00001996 liberalized, to allow leading zeroes. Examples of literals now
1997 legal that were SyntaxErrors before:
1998
1999 00.0 0e3 0100j 07.5 00000000000000000008.
2000
Tim Petersbdee63f2001-09-02 03:40:59 +00002001- An old tokenizer bug allowed floating point literals with an incomplete
Tim Petersc6d95812001-08-28 20:56:27 +00002002 exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
2003
Tim Petersedc99312001-08-22 21:36:50 +00002004Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002005-------
Tim Petersedc99312001-08-22 21:36:50 +00002006
Martin v. Löwiscb227c92001-09-06 08:54:16 +00002007- telnetlib includes symbolic names for the options, and support for
Martin v. Löwis1da9c572002-11-04 09:56:00 +00002008 setting an option negotiation callback. It also supports processing
2009 of suboptions.
Martin v. Löwiscb227c92001-09-06 08:54:16 +00002010
Tim Petersa40c7932001-09-05 22:36:56 +00002011- The new C standard no longer requires that math libraries set errno to
2012 ERANGE on overflow. For platform libraries that exploit this new
2013 freedom, Python's overflow-checking was wholly broken. A new overflow-
2014 checking scheme attempts to repair that, but may not be reliable on all
2015 platforms (C doesn't seem to provide anything both useful and portable
2016 in this area anymore).
2017
Martin v. Löwis44f86962001-09-05 13:44:54 +00002018- Asynchronous timeout actions are available through the new class
2019 threading.Timer.
2020
Tim Peters78526162001-09-05 00:53:45 +00002021- math.log and math.log10 now return sensible results for even huge
2022 long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
2023
Tim Petersbdee63f2001-09-02 03:40:59 +00002024- A new function, imp.lock_held(), returns 1 when the import lock is
Tim Peters69232342001-08-30 05:16:13 +00002025 currently held. See the docs for the imp module.
2026
Tim Petersbdee63f2001-09-02 03:40:59 +00002027- pickle, cPickle and marshal on 32-bit platforms can now correctly read
Tim Peters82112372001-08-29 02:28:42 +00002028 dumps containing ints written on platforms where Python ints are 8 bytes.
2029 When read on a box where Python ints are 4 bytes, such values are
2030 converted to Python longs.
2031
Tim Petersbdee63f2001-09-02 03:40:59 +00002032- In restricted execution mode (using the rexec module), unmarshalling
Guido van Rossumae457142001-08-31 18:31:35 +00002033 code objects is no longer allowed. This plugs a security hole.
2034
Steve Purcell6091cd62001-09-06 16:05:17 +00002035- unittest.TestResult instances no longer store references to tracebacks
2036 generated by test failures. This prevents unexpected dangling references
2037 to objects that should be garbage collected between tests.
2038
Tim Petersedc99312001-08-22 21:36:50 +00002039Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002040-----
Tim Petersedc99312001-08-22 21:36:50 +00002041
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002042- Tools/scripts/fixdiv.py has been added which can be used to fix
2043 division operators as per PEP 238.
2044
Tim Petersedc99312001-08-22 21:36:50 +00002045Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002046-----
Tim Petersedc99312001-08-22 21:36:50 +00002047
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002048- If you are an adventurous person using Mac OS X you may want to look at
2049 Mac/OSX. There is a Makefile there that will build Python as a real Mac
2050 application, which can be used for experimenting with Carbon or Cocoa.
2051 Discussion of this on pythonmac-sig, please.
2052
Tim Peters7eea37e2001-09-04 22:08:56 +00002053C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002054-----
Tim Peters7eea37e2001-09-04 22:08:56 +00002055
2056- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
Tim Peters69232342001-08-30 05:16:13 +00002057
Tim Peters9fffa3e2001-09-04 05:14:19 +00002058- Note that PyLong_AsDouble can fail! This has always been true, but no
2059 callers checked for it. It's more likely to fail now, because overflow
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002060 errors are properly detected now. The proper way to check::
Tim Peters9fffa3e2001-09-04 05:14:19 +00002061
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002062 double x = PyLong_AsDouble(some_long_object);
2063 if (x == -1.0 && PyErr_Occurred()) {
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002064 /* The conversion failed. */
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002065 }
Tim Peters9fffa3e2001-09-04 05:14:19 +00002066
Tim Petersbdee63f2001-09-02 03:40:59 +00002067- The GC API has been changed. Extensions that use the old API will still
Neil Schemenauer4042c692001-08-30 15:38:01 +00002068 compile but will not participate in GC. To upgrade an extension
2069 module:
2070
2071 - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
Tim Petersd507dab2001-08-30 20:51:59 +00002072
Neil Schemenauer4042c692001-08-30 15:38:01 +00002073 - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
2074 PyObject_GC_Del to deallocate them
Tim Petersd507dab2001-08-30 20:51:59 +00002075
Neil Schemenauer4042c692001-08-30 15:38:01 +00002076 - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
2077 to PyObject_GC_UnTrack
Tim Petersd507dab2001-08-30 20:51:59 +00002078
Neil Schemenauer4042c692001-08-30 15:38:01 +00002079 - remove PyGC_HEAD_SIZE from object size calculations
2080
2081 - remove calls to PyObject_AS_GC and PyObject_FROM_GC
2082
Tim Petersbdee63f2001-09-02 03:40:59 +00002083- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
Guido van Rossumae457142001-08-31 18:31:35 +00002084 These can be used safely to construct string objects from a
2085 sprintf-style format string (similar to the format string supported
2086 by PyErr_Format()).
Tim Peters69232342001-08-30 05:16:13 +00002087
Tim Petersedc99312001-08-22 21:36:50 +00002088New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002089-------------
Tim Petersedc99312001-08-22 21:36:50 +00002090
Tim Petersb7da0902001-09-02 23:01:43 +00002091- Stephen Hansen contributed patches sufficient to get a clean compile
2092 under Borland C (Windows), but he reports problems running it and ran
2093 out of time to complete the port. Volunteers? Expect a MemoryError
2094 when importing the types module; this is probably shallow, and
2095 causing later failures too.
Tim Petersbdee63f2001-09-02 03:40:59 +00002096
Tim Petersedc99312001-08-22 21:36:50 +00002097Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002098-----
Tim Petersedc99312001-08-22 21:36:50 +00002099
2100Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002101-------
Tim Petersedc99312001-08-22 21:36:50 +00002102
Tim Peters6e13a562001-09-06 00:32:15 +00002103- Large file support is now enabled on Win32 platforms as well as on
2104 Win64. This means that, for example, you can use f.tell() and f.seek()
2105 to manipulate files larger than 2 gigabytes (provided you have enough
2106 disk space, and are using a Windows filesystem that supports large
Tim Peters9a9471c2001-09-11 23:18:51 +00002107 partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
2108 filesize limit, and large file support makes no difference there.
2109 FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
2110 NTFS has no practical limit on file size, and files of any size can be
2111 used from Python now.
Tim Peters6e13a562001-09-06 00:32:15 +00002112
Tim Petersbdee63f2001-09-02 03:40:59 +00002113- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
Tim Peters402d5982001-08-27 06:37:48 +00002114 points to command.com (patch from Brian Quinlan).
2115
Tim Petersedc99312001-08-22 21:36:50 +00002116
Tim Peters20f51a72001-07-21 02:31:40 +00002117What's New in Python 2.2a2?
2118===========================
2119
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002120*Release Date: 22-Aug-2001*
2121
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002122Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002123-----
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002124
Barry Warsaw18b2ecf2001-08-22 20:26:56 +00002125- Tim Peters developed a brand new Windows installer using Wise 8.1,
2126 generously donated to us by Wise Solutions.
2127
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002128- configure supports a new option --enable-unicode, with the values
2129 ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
2130 type and supporting code is completely removed from the interpreter.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002131
Jack Jansen32ce0cd2001-08-21 19:28:20 +00002132- A new configure option --enable-framework builds a Mac OS X framework,
2133 which "make frameworkinstall" will install. This provides a starting
2134 point for more mac-like functionality, join pythonmac-sig@python.org
2135 if you are interested in helping.
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002136
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002137- The NeXT platform is no longer supported.
2138
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002139- The 'new' module is now statically linked.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002140
Tim Peters0afb6092001-08-15 06:06:44 +00002141Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002142-----
Tim Peters0afb6092001-08-15 06:06:44 +00002143
2144- The new Tools/scripts/cleanfuture.py can be used to automatically
Andrew M. Kuchlingb0532092001-08-15 15:54:56 +00002145 edit out obsolete future statements from Python source code. See
Tim Peters0afb6092001-08-15 06:06:44 +00002146 the module docstring for details.
2147
Tim Peters20f51a72001-07-21 02:31:40 +00002148Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002149-----
Tim Peters20f51a72001-07-21 02:31:40 +00002150
Tim Peters5e824c32001-08-12 22:25:01 +00002151- regrtest.py now knows which tests are expected to be skipped on some
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002152 platforms, allowing to give clearer test result output. regrtest
2153 also has optional --use/-u switch to run normally disabled tests
2154 which require network access or consume significant disk resources.
Tim Peters5e824c32001-08-12 22:25:01 +00002155
Tim Peters20f51a72001-07-21 02:31:40 +00002156- Several new tests in the standard test suite, with special thanks to
2157 Nick Mathewson.
2158
2159Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002160----
Tim Peters20f51a72001-07-21 02:31:40 +00002161
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002162- The floor division operator // has been added as outlined in PEP
2163 238. The / operator still provides classic division (and will until
2164 Python 3.0) unless "from __future__ import division" is included, in
2165 which case the / operator will provide true division. The operator
2166 module provides truediv() and floordiv() functions. Augmented
2167 assignment variants are included, as are the equivalent overloadable
2168 methods and C API methods. See the PEP for a full discussion:
2169 <http://python.sf.net/peps/pep-0238.html>
2170
Tim Peters6cd6a822001-08-17 22:11:27 +00002171- Future statements are now effective in simulated interactive shells
2172 (like IDLE). This should "just work" by magic, but read Michael
2173 Hudson's "Future statements in simulated shells" PEP 264 for full
2174 details: <http://python.sf.net/peps/pep-0264.html>.
2175
Guido van Rossumf86ddd22001-08-17 21:21:04 +00002176- The type/class unification (PEP 252-253) was integrated into the
2177 trunk and is not so tentative any more (the exact specification of
2178 some features is still tentative). A lot of work has done on fixing
2179 bugs and adding robustness and features (performance still has to
2180 come a long way).
2181
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002182- Warnings about a mismatch in the Python API during extension import
2183 now use the Python warning framework (which makes it possible to
2184 write filters for these warnings).
2185
Barry Warsaw9b3be7f2001-08-14 18:35:02 +00002186- A function's __dict__ (aka func_dict) will now always be a
2187 dictionary. It used to be possible to delete it or set it to None,
2188 but now both actions raise TypeErrors. It is still legal to set it
2189 to a dictionary object. Getting func.__dict__ before any attributes
2190 have been assigned now returns an empty dictionary instead of None.
2191
Guido van Rossum32aa5d22001-09-05 18:43:35 +00002192- A new command line option, -E, was added which disables the use of
2193 all environment variables, or at least those that are specifically
2194 significant to Python. Usually those have a name starting with
2195 "PYTHON". This was used to fix a problem where the tests fail if
2196 the user happens to have PYTHONHOME or PYTHONPATH pointing to an
2197 older distribution.
2198
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002199Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002200-------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002201
Tim Peters5e824c32001-08-12 22:25:01 +00002202- New class Differ and new functions ndiff() and restore() in difflib.py.
2203 These package the algorithms used by the popular Tools/scripts/ndiff.py,
Tim Peters0afb6092001-08-15 06:06:44 +00002204 for programmatic reuse.
Tim Peters5e824c32001-08-12 22:25:01 +00002205
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002206- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
2207 value using the minimal quoting required for the value; more
2208 reliable than using xml.sax.saxutils.escape() for attribute values.
2209
2210- Readline completion support for cmd.Cmd was added.
2211
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002212- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
2213
2214- Added function threading.BoundedSemaphore()
2215
2216- Added Ka-Ping Yee's cgitb.py module.
2217
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002218- The 'new' module now exposes the CO_xxx flags.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002219
Martin v. Löwis560da622001-11-24 09:24:51 +00002220- The gc module offers the get_referents function.
2221
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002222New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002223-------------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002224
2225C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002226-----
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002227
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002228- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
2229 which provide a cross-platform implementations for the
2230 relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
2231 the standard sprintf() and vsprintf() C lib APIs, these versions
2232 apply bounds checking on the used buffer which enhances protection
2233 against buffer overruns.
2234
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002235- Unicode APIs now use name mangling to assure that mixing interpreters
Tim Petersc1731372001-08-04 08:12:36 +00002236 and extensions using different Unicode widths is rendered next to
2237 impossible. Trying to import an incompatible Unicode-aware extension
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002238 will result in an ImportError. Unicode extensions writers must make
2239 sure to check the Unicode width compatibility in their extensions by
2240 using at least one of the mangled Unicode APIs in the extension.
2241
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002242- Two new flags METH_NOARGS and METH_O are available in method definition
2243 tables to simplify implementation of methods with no arguments and a
2244 single untyped argument. Calling such methods is more efficient than
2245 calling corresponding METH_VARARGS methods. METH_OLDARGS is now
2246 deprecated.
2247
Tim Petersc1731372001-08-04 08:12:36 +00002248Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002249-------
Tim Petersc1731372001-08-04 08:12:36 +00002250
2251- "import module" now compiles module.pyw if it exists and nothing else
2252 relevant is found.
2253
Tim Peters20f51a72001-07-21 02:31:40 +00002254
Guido van Rossum55a78992001-07-17 17:22:32 +00002255What's New in Python 2.2a1?
Tim Petersf553f892001-05-01 20:45:31 +00002256===========================
2257
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002258*Release date: 18-Jul-2001*
2259
Tim Petersf553f892001-05-01 20:45:31 +00002260Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002261----
Tim Petersa814db52001-05-14 07:05:58 +00002262
Tim Peters6d6c1a32001-08-02 04:15:00 +00002263- TENTATIVELY, a large amount of code implementing much of what's
2264 described in PEP 252 (Making Types Look More Like Classes) and PEP
2265 253 (Subtyping Built-in Types) was added. This will be released
2266 with Python 2.2a1. Documentation will be provided separately
2267 through http://www.python.org/2.2/. The purpose of releasing this
2268 with Python 2.2a1 is to test backwards compatibility. It is
2269 possible, though not likely, that a decision is made not to release
2270 this code as part of 2.2 final, if any serious backwards
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002271 incompatibilities are found during alpha testing that cannot be
Tim Peters6d6c1a32001-08-02 04:15:00 +00002272 repaired.
2273
Guido van Rossum55a78992001-07-17 17:22:32 +00002274- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +00002275 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +00002276 more 'yield' statements. See PEP 255. Since this adds a new
2277 keyword to the language, this feature must be enabled by including a
2278 future statement: "from __future__ import generators" (see PEP 236).
2279 Generators will become a standard feature in a future release
2280 (probably 2.3). Without this future statement, 'yield' remains an
2281 ordinary identifier, but a warning is issued each time it is used.
2282 (These warnings currently don't conform to the warnings framework of
2283 PEP 230; we intend to fix this in 2.2a2.)
2284
Marc-André Lemburg12e74b32001-05-22 08:58:23 +00002285- The UTF-16 codec was modified to be more RFC compliant. It will now
2286 only remove BOM characters at the start of the string and then
2287 only if running in native mode (UTF-16-LE and -BE won't remove a
2288 leading BMO character).
2289
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002290- Strings now have a new method .decode() to complement the already
2291 existing .encode() method. These two methods provide direct access
2292 to the corresponding decoders and encoders of the registered codecs.
2293
2294 To enhance the usability of the .encode() method, the special
2295 casing of Unicode object return values was dropped (Unicode objects
2296 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +00002297
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002298 Both methods will now return whatever the codec in charge of the
2299 requested encoding returns as object, e.g. Unicode codecs will
2300 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
2301 will return u"äöü"). This enables codec writer to create codecs
2302 for various simple to use conversions.
2303
2304 New codecs were added to demonstrate these new features (the .encode()
2305 and .decode() columns indicate the type of the returned objects):
2306
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002307 +---------+-----------+-----------+-----------------------------+
2308 |Name | .encode() | .decode() | Description |
2309 +=========+===========+===========+=============================+
2310 |uu | string | string | UU codec (e.g. for email) |
2311 +---------+-----------+-----------+-----------------------------+
2312 |base64 | string | string | base64 codec |
2313 +---------+-----------+-----------+-----------------------------+
2314 |quopri | string | string | quoted-printable codec |
2315 +---------+-----------+-----------+-----------------------------+
2316 |zlib | string | string | zlib compression |
2317 +---------+-----------+-----------+-----------------------------+
2318 |hex | string | string | 2-byte hex codec |
2319 +---------+-----------+-----------+-----------------------------+
2320 |rot-13 | string | Unicode | ROT-13 Unicode charmap codec|
2321 +---------+-----------+-----------+-----------------------------+
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002322
Mark Hammond2a0af792001-05-14 03:09:36 +00002323- Some operating systems now support the concept of a default Unicode
2324 encoding for file system operations. Notably, Windows supports 'mbcs'
2325 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002326 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +00002327 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002328
2329 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +00002330 functions that return filenames (such as os.listdir()) to return Python
2331 string objects pre-encoded using the default file system encoding for
2332 the platform. As this encoding is likely to be different from Python's
2333 default encoding, converting this name to a Unicode object before passing
2334 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +00002335 would attempt to use its default encoding (generally ASCII) rather than
2336 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002337
Tim Petersa814db52001-05-14 07:05:58 +00002338 In general, this change simply removes surprises when working with
2339 Unicode and the file system, making these operations work as you expect,
2340 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +00002341 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +00002342
Tim Peters61dff2b2001-05-08 15:43:37 +00002343- Float (and complex) literals in source code were evaluated to full
2344 precision only when running from a .py file; the same code loaded from a
2345 .pyc (or .pyo) file could suffer numeric differences starting at about the
2346 12th significant decimal digit. For example, on a machine with IEEE-754
2347 floating arithmetic,
2348
2349 x = 9007199254740992.0
2350 print long(x)
2351
2352 printed 9007199254740992 if run directly from .py, but 9007199254740000
2353 if from a compiled (.pyc or .pyo) file. This was due to marshal using
2354 str(float) instead of repr(float) when building code objects. marshal
2355 now uses repr(float) instead, which should reproduce floats to full
2356 machine precision (assuming the platform C float<->string I/O conversion
2357 functions are of good quality).
2358
2359 This may cause floating-point results to change in some cases, and
2360 usually for the better, but may also cause numerically unstable
2361 algorithms to break.
2362
Tim Peters2f228e72001-05-13 00:19:31 +00002363- The implementation of dicts suffers fewer collisions, which has speed
2364 benefits. However, the order in which dict entries appear in dict.keys(),
2365 dict.values() and dict.items() may differ from previous releases for a
2366 given dict. Nothing is defined about this order, so no program should
2367 rely on it. Nevertheless, it's easy to write test cases that rely on the
2368 order by accident, typically because of printing the str() or repr() of a
2369 dict to an "expected results" file. See Lib/test/test_support.py's new
2370 sortdict(dict) function for a simple way to display a dict in sorted
2371 order.
2372
Tim Peters7a3bfc32001-06-12 01:22:22 +00002373- Many other small changes to dicts were made, resulting in faster
2374 operation along the most common code paths.
2375
Guido van Rossum10315822001-05-01 20:54:30 +00002376- Dictionary objects now support the "in" operator: "x in dict" means
2377 the same as dict.has_key(x).
2378
Barry Warsaw51acc8d2001-06-26 20:12:50 +00002379- The update() method of dictionaries now accepts generic mapping
2380 objects. Specifically the argument object must support the .keys()
2381 and __getitem__() methods. This allows you to say, for example,
2382 {}.update(UserDict())
2383
Guido van Rossum10315822001-05-01 20:54:30 +00002384- Iterators were added; this is a generalized way of providing values
2385 to a for loop. See PEP 234. There's a new built-in function iter()
2386 to return an iterator. There's a new protocol to get the next value
2387 from an iterator using the next() method (in Python) or the
2388 tp_iternext slot (in C). There's a new protocol to get iterators
2389 using the __iter__() method (in Python) or the tp_iter slot (in C).
2390 Iterating (i.e. a for loop) over a dictionary generates its keys.
2391 Iterating over a file generates its lines.
2392
Tim Petersf553f892001-05-01 20:45:31 +00002393- The following functions were generalized to work nicely with iterator
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002394 arguments::
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002395
Tim Peterse63415e2001-05-08 04:38:29 +00002396 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +00002397 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
2398 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +00002399 join() method of strings
2400 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +00002401 'x in y' and 'x not in y' (PySequence_Contains() in C API)
2402 operator.countOf() (PySequence_Count() in C API)
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002403 right-hand side of assignment statements with multiple targets, such as ::
Tim Petersd6d010b2001-06-21 02:49:55 +00002404 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +00002405
Tim Petersd85e1022001-05-11 21:51:48 +00002406- Accessing module attributes is significantly faster (for example,
2407 random.random or os.path or yourPythonModule.yourAttribute).
2408
Tim Peterse63415e2001-05-08 04:38:29 +00002409- Comparing dictionary objects via == and != is faster, and now works even
2410 if the keys and values don't support comparisons other than ==.
2411
Tim Peters95bf9392001-05-10 08:32:44 +00002412- Comparing dictionaries in ways other than == and != is slower: there were
2413 insecurities in the dict comparison implementation that could cause Python
2414 to crash if the element comparison routines for the dict keys and/or
2415 values mutated the dicts. Making the code bulletproof slowed it down.
2416
Tim Peterseb28ef22001-06-02 05:27:19 +00002417- Collisions in dicts are resolved via a new approach, which can help
2418 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +00002419 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +00002420 faster now. Thanks to Christian Tismer for pointing out the cause and
2421 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +00002422
Tim Peters52e155e2001-06-16 05:42:57 +00002423- repr() is much faster for large containers (dict, list, tuple).
2424
2425
Tim Petersa814db52001-05-14 07:05:58 +00002426Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002427-------
Tim Petersa814db52001-05-14 07:05:58 +00002428
Fred Drake960fdf92001-07-20 18:38:26 +00002429- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002430 were added to the string module. These a locale-independent
Fred Drake960fdf92001-07-20 18:38:26 +00002431 constants, unlike letters, lowercase, and uppercase. These are now
2432 use in appropriate locations in the standard library.
2433
Martin v. Löwisf0473d52001-07-18 16:17:16 +00002434- The flags used in dlopen calls can now be configured using
2435 sys.setdlopenflags and queried using sys.getdlopenflags.
2436
Guido van Rossumc7e4aca2001-07-12 11:54:37 +00002437- Fredrik Lundh's xmlrpclib is now a standard library module. This
2438 provides full client-side XML-RPC support. In addition,
2439 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
2440 one asyncore-based). Thanks to Eric Raymond for the documentation.
2441
Guido van Rossum643d3912001-07-05 14:46:25 +00002442- The xrange() object is simplified: it no longer supports slicing,
2443 repetition, comparisons, efficient 'in' checking, the tolist()
2444 method, or the start, stop and step attributes. See PEP 260.
2445
Martin v. Löwisebf94db2001-06-06 06:25:40 +00002446- A new function fnmatch.filter to filter lists of file names was added.
2447
Barry Warsawffd674d2001-05-22 16:00:10 +00002448- calendar.py uses month and day names based on the current locale.
2449
Guido van Rossum2e0a6542001-05-15 02:14:44 +00002450- strop is now *really* obsolete (this was announced before with 1.6),
2451 and issues DeprecationWarning when used (except for the four items
2452 that are still imported into string.py).
2453
Tim Petersa814db52001-05-14 07:05:58 +00002454- Cookie.py now sorts key+value pairs by key in output strings.
2455
2456- pprint.isrecursive(object) didn't correctly identify recursive objects.
2457 Now it does.
2458
Tim Peters95b3f782001-05-14 18:39:41 +00002459- pprint functions now much faster for large containers (tuple, list, dict).
2460
Tim Peters7b9542a2001-06-10 23:40:19 +00002461- New 'q' and 'Q' format codes in the struct module, corresponding to C
2462 types "long long" and "unsigned long long" (on Windows, __int64). In
2463 native mode, these can be used only when the platform C compiler supports
2464 these types (when HAVE_LONG_LONG is #define'd by the Python config
2465 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +00002466 In standard mode, 'q' and 'Q' are supported on all platforms, and are
2467 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +00002468
Guido van Rossum83213cc2001-06-12 16:48:52 +00002469- The site module installs a new built-in function 'help' that invokes
2470 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
2471 it displays a message reminding the user to use 'help()' or
2472 'help(object)'.
2473
Tim Petersa814db52001-05-14 07:05:58 +00002474Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002475-----
Tim Petersa814db52001-05-14 07:05:58 +00002476
2477- New test_mutants.py runs dict comparisons where the key and value
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002478 comparison operators mutate the dicts randomly during comparison. This
Tim Petersa814db52001-05-14 07:05:58 +00002479 rapidly causes Python to crash under earlier releases (not for the faint
2480 of heart: it can also cause Win9x to freeze or reboot!).
2481
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002482- New test_pprint.py verifies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +00002483 pprint.isreadable() return sensible results. Also verifies that simple
2484 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +00002485
Tim Peters4324aa32001-05-28 22:30:08 +00002486C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002487-----
Tim Peters4324aa32001-05-28 22:30:08 +00002488
2489- Removed the unused last_is_sticky argument from the internal
2490 _PyTuple_Resize(). If this affects you, you were cheating.
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002491
2492----
2493
2494**(For information about older versions, consult the HISTORY file.)**