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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
Michael W. Hudsoncfd38842002-12-17 16:15:34 +000081- A frame object's f_lineno attribute can now be written to from a
82 trace function to change which line will execute next. A command to
83 exploit this from pdb has been added. [SF patch #643835]
84
Marc-André Lemburg20b91352002-12-12 18:01:43 +000085- The _codecs support module for codecs.py was turned into a builtin
86 module to assure that at least the builtin codecs are available
87 to the Python parser for source code decoding according to PEP 263.
88
Walter Dörwaldd9a6ad32002-12-12 16:41:44 +000089- issubclass now supports a tuple as the second argument, just like
90 isinstance does. ``issubclass(X, (A, B))`` is equivalent to
91 ``issubclass(X, A) or issubclass(X, B)``.
92
Tim Petersb9099c32002-11-12 22:08:10 +000093- Thanks to Armin Rigo, the last known way to provoke a system crash
94 by cleverly arranging for a comparison function to mutate a list
95 during a list.sort() operation has been fixed. The effect of
96 attempting to mutate a list, or even to inspect its contents or
97 length, while a sort is in progress, is not defined by the language.
98 The C implementation of Python 2.3 attempts to detect mutations,
99 and raise ValueError if one occurs, but there's no guarantee that
100 all mutations will be caught, or that any will be caught across
101 releases or implementations.
102
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000103- Unicode file name processing for Windows (PEP 277) is implemented.
Mark Hammond8696ebc2002-10-08 02:44:31 +0000104 All platforms now have an os.path.supports_unicode_filenames attribute,
105 which is set to True on Windows NT/2000/XP, and False elsewhere.
Martin v. Löwisa844f2d2002-10-05 09:46:48 +0000106
Walter Dörwald3aeb6322002-09-02 13:14:32 +0000107- Codec error handling callbacks (PEP 293) are implemented.
108 Error handling in unicode.encode or str.decode can now be customized.
109
Guido van Rossum45ec02a2002-08-19 21:43:18 +0000110- A subtle change to the semantics of the built-in function intern():
111 interned strings are no longer immortal. You must keep a reference
112 to the return value intern() around to get the benefit.
113
Guido van Rossumf808b892002-08-16 03:38:10 +0000114- Use of 'None' as a variable, argument or attribute name now
115 issues a SyntaxWarning. In the future, None may become a keyword.
116
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000117- SET_LINENO is gone. co_lnotab is now consulted to determine when to
118 call the trace function. C code that accessed f_lineno should call
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000119 PyCode_Addr2Line instead (f_lineno is still there, but only kept up
120 to date when there is a trace function set).
Michael W. Hudsondd32a912002-08-15 14:59:02 +0000121
Guido van Rossum9be89462002-08-14 16:11:30 +0000122- There's a new warning category, FutureWarning. This is used to warn
123 about a number of situations where the value or sign of an integer
124 result will change in Python 2.4 as a result of PEP 237 (integer
125 unification). The warnings implement stage B0 mentioned in that
126 PEP. The warnings are about the following situations:
127
128 - Octal and hex literals without 'L' prefix in the inclusive range
129 [0x80000000..0xffffffff]; these are currently negative ints, but
130 in Python 2.4 they will be positive longs with the same bit
131 pattern.
132
133 - Left shifts on integer values that cause the outcome to lose
134 bits or have a different sign than the left operand. To be
135 precise: x<<n where this currently doesn't yield the same value
136 as long(x)<<n; in Python 2.4, the outcome will be long(x)<<n.
137
138 - Conversions from ints to string that show negative values as
139 unsigned ints in the inclusive range [0x80000000..0xffffffff];
140 this affects the functions hex() and oct(), and the string
141 formatting codes %u, %o, %x, and %X. In Python 2.4, these will
142 show signed values (e.g. hex(-1) currently returns "0xffffffff";
143 in Python 2.4 it will return "-0x1").
144
Skip Montanaro979c74b2002-09-03 21:25:14 +0000145 - The bits manipulated under the cover by sys.setcheckinterval() have
146 been changed. Both the check interval and the ticker used to be
147 per-thread values. They are now just a pair of global variables. In
148 addition, the default check interval was boosted from 10 to 100
Neal Norwitz7165af22002-09-05 21:42:24 +0000149 bytecode instructions. This may have some effect on systems that
150 relied on the old default value. In particular, in multi-threaded
151 applications which try to be highly responsive, response time will
152 increase by some (perhaps imperceptible) amount.
Skip Montanaro979c74b2002-09-03 21:25:14 +0000153
Tim Petersd64c1de2002-08-12 17:36:03 +0000154- When multiplying very large integers, a version of the so-called
155 Karatsuba algorithm is now used. This is most effective if the
156 inputs have roughly the same size. If they both have about N digits,
157 Karatsuba multiplication has O(N**1.58) runtime (the exponent is
158 log_base_2(3)) instead of the previous O(N**2). Measured results may
Tim Peters012c0a32002-08-16 03:40:07 +0000159 be better or worse than that, depending on platform quirks. Besides
160 the O() improvement in raw instruction count, the Karatsuba algorithm
161 appears to have much better cache behavior on extremely large integers
162 (starting in the ballpark of a million bits). Note that this is a
163 simple implementation, and there's no intent here to compete with,
164 e.g., GMP. It gives a very nice speedup when it applies, but a package
165 devoted to fast large-integer arithmetic should run circles around it.
Tim Peters5af4e6c2002-08-12 02:31:19 +0000166
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000167- u'%c' will now raise a ValueError in case the argument is an
168 integer outside the valid range of Unicode code point ordinals.
169
Guido van Rossumdeb09362002-08-09 17:16:30 +0000170- The tempfile module has been overhauled for enhanced security. The
171 mktemp() function is now deprecated; new, safe replacements are
172 mkstemp() (for files) and mkdtemp() (for directories), and the
173 higher-level functions NamedTemporaryFile() and TemporaryFile().
174 Use of some global variables in this module is also deprecated; the
175 new functions have keyword arguments to provide the same
176 functionality. All Lib, Tools and Demo modules that used the unsafe
177 interfaces have been updated to use the safe replacements. Thanks
178 to Zack Weinberg!
179
Guido van Rossumd81a9832002-08-09 15:57:34 +0000180- When x is an object whose class implements __mul__ and __rmul__,
181 1.0*x would correctly invoke __rmul__, but 1*x would erroneously
182 invoke __mul__. This was due to the sequence-repeat code in the int
183 type. This has been fixed now.
184
Barry Warsawd79f6832002-08-06 17:01:51 +0000185- Previously, "str1 in str2" required str1 to be a string of length 1.
186 This restriction has been relaxed to allow str1 to be a string of
187 any length. Thus "'el' in 'hello world'" returns True now.
188
Guido van Rossumb57089c2002-08-06 16:20:26 +0000189- File objects are now their own iterators. For a file f, iter(f) now
190 returns f (unless f is closed), and f.next() is similar to
191 f.readline() when EOF is not reached; however, f.next() uses a
192 readahead buffer that messes up the file position, so mixing
193 f.next() and f.readline() (or other methods) doesn't work right.
194 Calling f.seek() drops the readahead buffer, but other operations
195 don't. It so happens that this gives a nice additional speed boost
196 to "for line in file:"; the xreadlines method and corresponding
Guido van Rossumbffb2ef2002-08-09 17:17:07 +0000197 module are now obsolete. Thanks to Oren Tirosh!
Guido van Rossumb57089c2002-08-06 16:20:26 +0000198
Guido van Rossumde392d32002-08-05 14:17:20 +0000199- Encoding declarations (PEP 263, phase 1) have been implemented. A
200 comment of the form "# -*- coding: <encodingname> -*-" in the first
201 or second line of a Python source file indicates the encoding.
Martin v. Löwis00f1e3f2002-08-04 17:29:52 +0000202
Tim Petersf47630f2002-08-01 02:34:51 +0000203- list.sort() has a new implementation. While cross-platform results
204 may vary, and in data-dependent ways, this is much faster on many
205 kinds of partially ordered lists than the previous implementation,
206 and reported to be just as fast on randomly ordered lists on
207 several major platforms. This sort is also stable (if A==B and A
208 precedes B in the list at the start, A precedes B after the sort too),
209 although the language definition does not guarantee stability. A
210 potential drawback is that list.sort() may require temp space of
Skip Montanaroa2a07bc2002-09-30 15:23:01 +0000211 len(list)*2 bytes (``*4`` on a 64-bit machine). It's therefore possible
Tim Petersf47630f2002-08-01 02:34:51 +0000212 for list.sort() to raise MemoryError now, even if a comparison function
213 does not. See <http://www.python.org/sf/587076> for full details.
214
Guido van Rossum2d5389c2002-07-23 03:44:35 +0000215- All standard iterators now ensure that, once StopIteration has been
216 raised, all future calls to next() on the same iterator will also
217 raise StopIteration. There used to be various counterexamples to
218 this behavior, which could caused confusion or subtle program
219 breakage, without any benefits. (Note that this is still an
220 iterator's responsibility; the iterator framework does not enforce
221 this.)
222
Mark Hammondc0e35152002-07-16 01:32:30 +0000223- Ctrl+C handling on Windows has been made more consistent with
224 other platforms. KeyboardInterrupt can now reliably be caught,
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000225 and Ctrl+C at an interactive prompt no longer terminates the
Mark Hammondc0e35152002-07-16 01:32:30 +0000226 process under NT/2k/XP (it never did under Win9x). Ctrl+C will
Tim Peters5af4e6c2002-08-12 02:31:19 +0000227 interrupt time.sleep() in the main thread, and any child processes
228 created via the popen family (on win2k; we can't make win9x work
Mark Hammond8f3afc72002-08-10 06:26:31 +0000229 reliably) are also interrupted (as generally happens on for Linux/Unix.)
230 [SF bugs 231273, 439992 and 581232]
Mark Hammondc0e35152002-07-16 01:32:30 +0000231
Mark Hammond8696ebc2002-10-08 02:44:31 +0000232- sys.getwindowsversion() has been added on Windows. This
233 returns a tuple with information about the version of Windows
234 currently running.
235
Raymond Hettinger5a04aec2002-06-25 00:25:30 +0000236- Slices and repetitions of buffer objects now consistently return
237 a string. Formerly, strings would be returned most of the time,
238 but a buffer object would be returned when the repetition count
239 was one or when the slice range was all inclusive.
240
Walter Dörwald3430d702002-06-17 10:43:59 +0000241- Unicode objects in sys.path are no longer ignored but treated
242 as directory names.
243
Neal Norwitz1f68fc72002-06-14 00:50:42 +0000244- Fixed string.startswith and string.endswith builtin methods
245 so they accept negative indices. [SF bug 493951]
246
Guido van Rossumc5fe5eb2002-06-12 03:45:21 +0000247- Fixed a bug with a continue inside a try block and a yield in the
248 finally clause. [SF bug 567538]
249
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000250- Most builtin sequences now support "extended slices", i.e. slices
Guido van Rossum2e82e712002-06-13 11:41:07 +0000251 with a third "stride" parameter. For example, "hello world"[::-1]
252 gives "dlrow olleh".
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000253
Neal Norwitzd68f5172002-05-29 15:54:55 +0000254- A new warning PendingDeprecationWarning was added to provide
255 direction on features which are in the process of being deprecated.
256 The warning will not be printed by default. To see the pending
257 deprecations, use -Walways::PendingDeprecationWarning::
258 as a command line option or warnings.filterwarnings() in code.
259
Fred Draked0ba6362002-05-02 21:28:26 +0000260- Deprecated features of xrange objects have been removed as
261 promised. The start, stop, and step attributes and the tolist()
262 method no longer exist. xrange repetition and slicing have been
263 removed.
264
Guido van Rossum7dab2422002-04-26 19:40:56 +0000265- New builtin function enumerate(x), from PEP 279. Example:
266 enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
267 The argument can be an arbitrary iterable object.
268
Neil Schemenauer89e3ee02002-04-26 01:58:53 +0000269- The assert statement no longer tests __debug__ at runtime. This means
270 that assert statements cannot be disabled by assigning a false value
271 to __debug__.
272
Walter Dörwald068325e2002-04-15 13:36:47 +0000273- A method zfill() was added to str and unicode, that fills a numeric
274 string to the left with zeros. For example,
275 "+123".zfill(6) -> "+00123".
276
Guido van Rossum862fe3c2002-04-15 12:36:47 +0000277- Complex numbers supported divmod() and the // and % operators, but
278 these make no sense. Since this was documented, they're being
279 deprecated now.
280
Guido van Rossum26dd8302002-04-26 20:11:29 +0000281- String and unicode methods lstrip(), rstrip() and strip() now take
282 an optional argument that specifies the characters to strip. For
283 example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
Guido van Rossum49042042002-04-13 00:59:05 +0000284
Guido van Rossumc0d3f4e2002-11-27 13:10:40 +0000285- There's a new dictionary constructor (a class method of the dict
286 class), dict.fromkeys(iterable, value=None). It constructs a
287 dictionary with keys taken from the iterable and all values set to a
288 single value. It can be used for building sets and for removing
289 duplicates from sequences.
Raymond Hettingere33d3df2002-11-27 07:29:33 +0000290
Guido van Rossumc69343b2002-04-12 19:22:48 +0000291- Added a new dict method pop(key). This removes and returns the
292 value corresponding to key. [SF patch #539949]
293
Guido van Rossum47834462002-04-04 15:21:33 +0000294- A new built-in type, bool, has been added, as well as built-in
295 names for its two values, True and False. Comparisons and sundry
296 other operations that return a truth value have been changed to
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000297 return a bool instead. Read PEP 285 for an explanation of why this
Guido van Rossum47834462002-04-04 15:21:33 +0000298 is backward compatible.
299
Guido van Rossum95b62a62002-03-29 01:07:24 +0000300- Fixed two bugs reported as SF #535905: under certain conditions,
301 deallocating a deeply nested structure could cause a segfault in the
302 garbage collector, due to interaction with the "trashcan" code;
303 access to the current frame during destruction of a local variable
304 could access a pointer to freed memory.
305
Guido van Rossumfe0ca4a2002-06-18 21:20:13 +0000306- The optional object allocator ("pymalloc") has been enabled by
307 default. The recommended practice for memory allocation and
308 deallocation has been streamlined. A header file is included,
309 Misc/pymemcompat.h, which can be bundled with 3rd party extensions
310 and lets them use the same API with Python versions from 1.5.2
311 onwards.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000312
Martin v. Löwiscfeb3b62002-03-03 21:30:27 +0000313- PyErr_Display will provide file and line information for all exceptions
314 that have an attribute print_file_and_line, not just SyntaxErrors.
315
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000316- The UTF-8 codec will now encode and decode Unicode surrogates
317 correctly and without raising exceptions for unpaired ones.
318
Guido van Rossumadd88062002-08-15 14:01:14 +0000319- Universal newlines (PEP 278) is implemented. Briefly, using 'U'
320 instead of 'r' when opening a text file for reading changes the line
321 ending convention so that any of '\r', '\r\n', and '\n' is
322 recognized (even mixed in one file); all three are converted to
323 '\n', the standard Python line end character.
324
Neal Norwitz649b7592002-01-01 19:07:13 +0000325- file.xreadlines() now raises a ValueError if the file is closed:
326 Previously, an xreadlines object was returned which would raise
327 a ValueError when the xreadlines.next() method was called.
328
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000329- sys.exit() inadvertently allowed more than one argument.
Neal Norwitz0c766a02002-03-27 13:03:09 +0000330 An exception will now be raised if more than one argument is used.
331
Gustavo Niemeyer17c5a332002-12-16 14:09:22 +0000332- Changed evaluation order of dictionary literals to conform to the
333 general left to right evaluation order rule. Now {f1(): f2()} will
334 evaluate f1 first.
Gustavo Niemeyer78429a62002-12-16 13:54:02 +0000335
Gustavo Niemeyer786ddb22002-12-16 18:12:53 +0000336- Fixed bug #521782: when a file was in non-blocking mode, file.read()
337 could silently lose data or wrongly throw an unknown error.
338
Neil Schemenauerb983aa02002-12-30 20:22:23 +0000339- The sq_repeat, sq_inplace_repeat, sq_concat and sq_inplace_concat
340 slots are now always tried after trying the corresponding nb_* slots.
341 This fixes a number of minor bugs (see bug #624807).
342
Tim Petersaf8446f2001-12-21 21:36:50 +0000343Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000344-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000345
Tim Peterse820cb62002-12-16 20:57:22 +0000346- The new datetime module supplies classes for manipulating dates and
347 times. The basic design came from the Zope "fishbowl process", and
348 favors practical commercial applications over calendar esoterica. See
349
350 http://www.zope.org/Members/fdrake/DateTimeWiki/FrontPage
351
Martin v. Löwisffad6332002-11-26 09:28:05 +0000352- _tkinter now returns Tcl objects, instead of strings. Objects which
353 have Python equivalents are converted to Python objects, other objects
354 are wrapped. This can be configured through the wantobjects method,
Martin v. Löwis8c8aa5d2002-11-26 21:39:48 +0000355 or Tkinter.wantobjects.
Martin v. Löwisffad6332002-11-26 09:28:05 +0000356
Barry Warsawc27f4bd2002-12-30 21:03:26 +0000357- The PyBSDDB wrapper around the Sleepycat Berkeley DB library has
358 been added as the package bsddb. The traditional bsddb module is
359 still available in source code, but not built automatically anymore,
360 and is now named bsddb185. This supports Berkeley DB versions from
361 3.0 to 4.1.
Martin v. Löwisef546b32002-11-19 08:12:57 +0000362
Martin v. Löwis677bde22002-11-23 22:08:15 +0000363- unicodedata was updated to Unicode 3.2. It supports normalization
364 and names for Hangul syllables and CJK unified ideographs.
Martin v. Löwis7d41e292002-11-23 12:22:32 +0000365
Neal Norwitz94a83fd2002-11-02 17:46:24 +0000366- resource.getrlimit() now returns longs instead of ints.
367
Martin v. Löwis080689c2002-10-26 14:42:02 +0000368- readline now dynamically adjusts its input/output stream if
369 sys.stdin/stdout changes.
370
Guido van Rossumba602972002-10-01 18:18:58 +0000371- The _tkinter module (and hence Tkinter) has dropped support for
372 Tcl/Tk 8.0 and 8.1. Only Tcl/Tk versions 8.2, 8.3 and 8.4 are
373 supported.
374
Martin v. Löwis658009a2002-09-16 17:26:24 +0000375- cPickle.BadPickleGet is now a class.
376
Martin v. Löwisa19bfe02002-10-16 18:28:36 +0000377- The time stamps in os.stat_result are floating point numbers
378 after stat_float_times has been called.
Martin v. Löwis94717ed2002-09-09 14:24:16 +0000379
Neal Norwitzb5673922002-09-05 21:48:07 +0000380- If the size passed to mmap.mmap() is larger than the length of the
381 file on non-Windows platforms, a ValueError is raised. [SF bug 585792]
382
Guido van Rossumb57089c2002-08-06 16:20:26 +0000383- The xreadlines module is slated for obsolescence.
384
Guido van Rossum79f0a102002-07-23 03:32:08 +0000385- The strptime function in the time module is now always available (a
386 Python implementation is used when the C library doesn't define it).
387
Guido van Rossum9562bcf2002-06-14 21:31:18 +0000388- The 'new' module is no longer an extension, but a Python module that
389 only exists for backwards compatibility. Its contents are no longer
390 functions but callable type objects.
391
Tim Peters81b92512002-04-29 01:37:32 +0000392- The bsddb.*open functions can now take 'None' as a filename.
Anthony Baxter83888952002-04-23 02:11:05 +0000393 This will create a temporary in-memory bsddb that won't be
Tim Peters81b92512002-04-29 01:37:32 +0000394 written to disk.
Anthony Baxter83888952002-04-23 02:11:05 +0000395
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +0000396- posix.lchown, posix.killpg, posix.mknod, and posix.getpgid have been
397 added where available.
Martin v. Löwis06a83e92002-04-14 10:19:44 +0000398
Martin v. Löwisf0a46682002-11-03 17:20:12 +0000399- The locale module now exposes the C library's gettext interface. It
400 also has a new function getpreferredencoding.
Martin v. Löwis2e64c342002-03-27 18:49:02 +0000401
Tim Petersfbf74f22002-03-14 19:06:01 +0000402- A security hole ("double free") was found in zlib-1.1.3, a popular
403 third party compression library used by some Python modules. The
404 hole was quickly plugged in zlib-1.1.4, and the Windows build of
405 Python now ships with zlib-1.1.4.
406
Martin v. Löwis688357e2002-04-08 21:28:20 +0000407- pwd, grp, and resource return enhanced tuples now, with symbolic
408 field names.
Martin v. Löwis29001ff2002-03-01 10:47:37 +0000409
Martin v. Löwis99866332002-03-01 10:27:01 +0000410- array.array is now a type object. A new format character
411 'u' indicates Py_UNICODE arrays. For those, .tounicode and
412 .fromunicode methods are available. Arrays now support __iadd__
413 and __imul__.
414
Neal Norwitze790eae2002-01-01 21:14:12 +0000415- dl now builds on every system that has dlfcn.h. Failure in case
Martin v. Löwis93227272002-01-01 20:18:30 +0000416 of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
417 is called.
418
Michael W. Hudson34f20ea2002-05-27 15:08:24 +0000419- signal.sigpending, signal.sigprocmask and signal.sigsuspend have
420 been added where available.
421
Skip Montanaro8e790e72002-09-03 13:25:17 +0000422- The sys module acquired a new attribute, api_version, which evaluates
423 to the value of the PYTHON_API_VERSION macro with which the
424 interpreter was compiled.
425
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000426- Fixed bug #470582: sre module would return a tuple (None, 'a', 'ab')
427 when applying the regular expression '^((a)c)?(ab)$' on 'ab'. It now
428 returns (None, None, 'ab'), as expected. Also fixed handling of
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +0000429 lastindex/lastgroup match attributes in similar cases. For example,
Gustavo Niemeyer4e7be062002-11-06 14:06:53 +0000430 when running the expression r'(a)(b)?b' over 'ab', lastindex must be
431 1, not 2.
432
Gustavo Niemeyerc523b042002-11-07 03:28:56 +0000433- Fixed bug #581080: sre scanner was not checking the buffer limit
434 before increasing the current pointer. This was creating an infinite
435 loop in the search function, once the pointer exceeded the buffer
436 limit.
437
Thomas Heller95cb7e42002-11-07 16:23:55 +0000438- The os.fdopen function now enforces a file mode starting with the
439 letter 'r', 'w' or 'a', otherwise a ValueError is raised. This fixes
440 bug #623464.
441
Tim Petersaf8446f2001-12-21 21:36:50 +0000442Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000443-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000444
Raymond Hettingeraf72d522002-12-29 20:14:11 +0000445- unittest.py now has two additional methods called assertAlmostEqual()
446 and failIfAlmostEqual(). They implement an approximate comparision
447 by rounding the difference between the two arguments and comparing
448 the result to zero. Approximate comparision is essential for
449 unit tests of floating point results.
450
Raymond Hettingere11b5102002-12-25 16:37:19 +0000451- calendar.py now depends on the new datetime module rather than
452 the time module. As a result, the range of allowable dates
453 has been increased.
454
Michael W. Hudsoncfd38842002-12-17 16:15:34 +0000455- pdb has a new 'j(ump)' command to select the next line to be
456 executed.
457
Thomas Heller1b3b49d2002-12-12 19:13:44 +0000458- The distutils created windows installers now can run a
459 postinstallation script.
460
Martin v. Löwis4581cfa2002-11-22 08:23:09 +0000461- doctest.testmod can now be called without argument, which means to
462 test the current module.
463
Martin v. Löwisf86e8ef2002-11-22 08:08:44 +0000464- When cancelling a server that implemented threading with a keyboard
465 interrupt, the server would shut down but not terminate (waiting on
466 client threads). A new member variable, daemon_threads, was added to
467 the ThreadingMixIn class in SocketServer.py to make it explicit that
468 this behavior needs to be controlled.
469
Guido van Rossum545c2502002-11-15 13:19:58 +0000470- A new module, optparse, provides a fancy alternative to getopt for
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000471 command line parsing. It is a slightly modified version of Greg
Guido van Rossum545c2502002-11-15 13:19:58 +0000472 Ward's Optik package.
473
Raymond Hettinger79947162002-11-15 06:46:14 +0000474- UserDict.py now defines a DictMixin class which defines all dictionary
475 methods for classes that already have a minimum mapping interface.
476 This greatly simplifies writing classes that need to be substitutable
477 for dictionaries (such as the shelve module).
478
479- shelve.py now subclasses from UserDict.DictMixin. Now shelve supports
480 all dictionary methods. This eases the transition to persistent
Andrew M. Kuchlinge0373f82002-11-15 14:42:34 +0000481 storage for scripts originally written with dictionaries in mind.
Raymond Hettinger79947162002-11-15 06:46:14 +0000482
Skip Montanaro3bf99e32002-12-08 18:36:24 +0000483- shelve.open and the various classes in shelve.py now accept an optional
484 binary flag, which defaults to False. If True, the values stored in the
485 shelf are binary pickles.
486
Guido van Rossumfda06742002-11-13 16:29:18 +0000487- A new package, logging, implements the logging API defined by PEP
488 282. The code is written by Vinay Sajip.
489
Walter Dörwald4dbf1922002-11-06 16:53:44 +0000490- StreamReader, StreamReaderWriter and StreamRecoder in the codecs
491 modules are iterators now.
492
Tim Peters9288f952002-11-05 20:38:55 +0000493- gzip.py now handles files exceeding 2GB. Files over 4GB also work
494 now (provided the OS supports it, and Python is configured with large
495 file support), but in that case the underlying gzip file format can
496 record only the least-significant 32 bits of the file size, so that
497 some tools working with gzipped files may report an incorrect file
498 size.
Tim Petersfb0ea522002-11-04 19:50:11 +0000499
Martin v. Löwis74b51ac2002-10-26 14:50:45 +0000500- xml.sax.saxutils.unescape has been added, to replace entity references
501 with their entity value.
502
Martin v. Löwis77ac4292002-10-15 15:11:13 +0000503- Queue.Queue.{put,get} now support an optional timeout argument.
504
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000505- Various features of Tk 8.4 are exposed in Tkinter.py. The multiple
506 option of tkFileDialog is exposed as function askopenfile{,name}s.
Martin v. Löwis2ec36272002-10-13 10:22:08 +0000507
Martin v. Löwisb24e3472002-10-13 10:28:04 +0000508- Various configure methods of Tkinter have been stream-lined, so that
509 tag_configure, image_configure, window_configure now return a
Tim Petersfb0ea522002-11-04 19:50:11 +0000510 dictionary when invoked with no argument.
Martin v. Löwis6ce13152002-10-10 14:36:13 +0000511
Guido van Rossum2b492b62002-10-09 21:40:48 +0000512- Importing the readline module now no longer has the side effect of
513 calling setlocale(LC_CTYPE, ""). The initial "C" locale, or
514 whatever locale is explicitly set by the user, is preserved. If you
515 want repr() of 8-bit strings in your preferred encoding to preserve
516 all printable characters of that encoding, you have to add the
517 following code to your $PYTHONSTARTUP file or to your application's
518 main():
519
520 import locale
521 locale.setlocale(locale.LC_CTYPE, "")
522
Martin v. Löwise9ce0b02002-10-07 13:23:24 +0000523- shutil.move was added. shutil.copytree now reports errors as an
524 exception at the end, instead of printing error messages.
525
Marc-André Lemburg97047e22002-10-04 11:55:21 +0000526- Encoding name normalization was generalized to not only
527 replace hyphens with underscores, but also all other non-alphanumeric
528 characters (with the exception of the dot which is used for Python
529 package names during lookup). The aliases.py mapping was updated
530 to the new standard.
531
Walter Dörwald5ccaf8f2002-09-06 16:15:58 +0000532- mimetypes has two new functions: guess_all_extensions() which
533 returns a list of all known extensions for a mime type, and
534 add_type() which adds one mapping between a mime type and
535 an extension to the database.
536
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000537- New module: sets, defines the class Set that implements a mutable
538 set type using the keys of a dict to represent the set. There's
539 also a class ImmutableSet which is useful when you need sets of sets
540 or when you need to use sets as dict keys, and a class BaseSet which
Raymond Hettingeref8b9c62002-12-09 08:56:06 +0000541 is the base class of the two.
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000542
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000543- Added operator.pow(a,b) which is equivalent to a**b.
544
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000545- Added random.sample(population,k) for random sampling without replacement.
Tim Petersb9099c32002-11-12 22:08:10 +0000546 Returns a k length list of unique elements chosen from the population.
Raymond Hettingerf24eb352002-11-12 17:41:57 +0000547
Tim Peters012c0a32002-08-16 03:40:07 +0000548- random.randrange(-sys.maxint-1, sys.maxint) no longer raises
549 OverflowError. That is, it now accepts any combination of 'start'
550 and 'stop' arguments so long as each is in the range of Python's
551 bounded integers.
552
Raymond Hettinger40f62172002-12-29 23:03:38 +0000553- Thanks to Raymond Hettinger, random.random() now uses a new core
554 generator. The Mersenne Twister algorithm is implemented in C,
555 threadsafe, faster than the previous generator, has an astronomically
556 large period (2**19937-1), creates random floats to full 53-bit
557 precision, and may be the most widely tested random number generator
558 in existence.
559
560 The random.jumpahead(n) method has different semantics for the new
561 generator. Instead of jumping n steps ahead, it uses n and the
562 existing state to create a new state. This means that jumpahead()
563 continues to support multi-threaded code needing generators of
564 non-overlapping sequences. However, it will break code which relies
565 on jumpahead moving a specific number of steps forward.
566
567 The attributes random.whseed and random.__whseed have no meaning for
568 the new generator. Code using these attributes should switch to a
569 new class, random.WichmannHill which is provided for backward
570 compatibility and to make an alternate generator available.
571
Guido van Rossum4a57c332002-08-02 18:05:20 +0000572- New "algorithms" module: heapq, implements a heap queue. Thanks to
573 Kevin O'Connor for the code and François Pinard for an entertaining
574 write-up explaining the theory and practical uses of heaps.
575
Marc-André Lemburg58e2ff22002-07-12 14:40:04 +0000576- New encoding for the Palm OS character set: palmos.
577
Tim Peters943382c2002-07-07 03:59:34 +0000578- binascii.crc32() and the zipfile module had problems on some 64-bit
579 platforms. These have been fixed. On a platform with 8-byte C longs,
580 crc32() now returns a signed-extended 4-byte result, so that its value
581 as a Python int is equal to the value computed a 32-bit platform.
582
Martin v. Löwis7d650ca2002-06-30 15:05:00 +0000583- xml.dom.minidom.toxml and toprettyxml now take an optional encoding
584 argument.
585
Guido van Rossum9f7549b2002-06-10 21:39:42 +0000586- Some fixes in the copy module: when an object is copied through its
587 __reduce__ method, there was no check for a __setstate__ method on
588 the result [SF patch 565085]; deepcopy should treat instances of
589 custom metaclasses the same way it treats instances of type 'type'
590 [SF patch 560794].
591
Guido van Rossum5033c8e2002-06-07 12:40:52 +0000592- Sockets now support timeout mode. After s.settimeout(T), where T is
593 a float expressing seconds, subsequent operations raise an exception
594 if they cannot be completed within T seconds. To disable timeout
Guido van Rossum79f0a102002-07-23 03:32:08 +0000595 mode, use s.settimeout(None). There's also a module function,
596 socket.setdefaulttimeout(T), which sets the default for all sockets
597 created henceforth.
Guido van Rossum5033c8e2002-06-07 12:40:52 +0000598
599- getopt.gnu_getopt was added. This supports GNU-style option
600 processing, where options can be mixed with non-option arguments.
Martin v. Löwis446a25f2002-06-06 10:58:36 +0000601
Michael W. Hudsonb0dc1a32002-06-04 18:27:35 +0000602- Stop using strings for exceptions. String objects used for
603 exceptions are now classes deriving from Exception. The objects
604 changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
605 tabnanny.NannyNag, and xdrlib.Error.
Neal Norwitzb5b5a262002-06-04 17:14:07 +0000606
Walter Dörwald474458d2002-06-04 15:16:29 +0000607- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
608 BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
609 Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
610 big endian systems were added to the codecs module. The old names
611 BOM32_* and BOM64_* were off by a factor of 2.
612
Guido van Rossumf9257822002-06-18 20:43:18 +0000613- Added conversion functions math.degrees() and math.radians().
Raymond Hettinger87f59ee2002-05-13 04:17:32 +0000614
Raymond Hettinger866964c2002-12-14 19:51:34 +0000615- math.log() now takes an optional argument: math.log(x[, base]).
616
Raymond Hettinger9b1df1d2002-05-12 06:07:21 +0000617- ftplib.retrlines() now tests for callback is None rather than testing
618 for False. Was causing an error when given a callback object which
619 was callable but also returned len() as zero. The change may
620 create new breakage if the caller relied on the undocumented behavior
621 and called with callback set to [] or some other False value not
622 identical to None.
623
Tim Peters46c04e12002-05-05 20:40:00 +0000624- random.gauss() uses a piece of hidden state used by nothing else,
625 and the .seed() and .whseed() methods failed to reset it. In other
626 words, setting the seed didn't completely determine the sequence of
627 results produced by random.gauss(). It does now. Programs repeatedly
628 mixing calls to a seed method with calls to gauss() may see different
629 results now.
630
Fred Drake7f781c92002-05-01 20:33:53 +0000631- The pickle.Pickler class grew a clear_memo() method to mimic that
632 provided by cPickle.Pickler.
633
Tim Peters81b92512002-04-29 01:37:32 +0000634- difflib's SequenceMatcher class now does a dynamic analysis of
635 which elements are so frequent as to constitute noise. For
636 comparing files as sequences of lines, this generally works better
637 than the IS_LINE_JUNK function, and function ndiff's linejunk
638 argument defaults to None now as a result. A happy benefit is
639 that SequenceMatcher may run much faster now when applied
640 to large files with many duplicate lines (for example, C program
641 text with lots of repeated "}" and "return NULL;" lines).
642
Guido van Rossum256705b2002-04-23 13:29:43 +0000643- New Text.dump() method in Tkinter module.
644
Marc-André Lemburg1ec71ea2002-04-17 20:33:40 +0000645- New distutils commands for building packagers were added to
646 support pkgtool on Solaris and swinstall on HP-UX.
647
648- distutils now has a new abstract binary packager base class
649 command/bdist_packager, which simplifies writing packagers.
650 This will hopefully provide the missing bits to encourage
651 people to submit more packagers, e.g. for Debian, FreeBSD
652 and other systems.
653
Guido van Rossumf9257822002-06-18 20:43:18 +0000654- The UTF-16, -LE and -BE stream readers now raise a
655 NotImplementedError for all calls to .readline(). Previously, they
656 used to just produce garbage or fail with an encoding error --
657 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 +0000658 work well with these.
659
Martin v. Löwis5c137c22002-03-18 12:44:08 +0000660- compileall now supports quiet operation.
661
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000662- The BaseHTTPServer now implements optional HTTP/1.1 persistent
Martin v. Löwis587c98c2002-03-17 18:37:22 +0000663 connections.
664
Marc-André Lemburga5d2b4c2002-02-16 18:23:30 +0000665- socket module: the SSL support was broken out of the main
666 _socket module C helper and placed into a new _ssl helper
667 which now gets imported by socket.py if available and working.
668
Marc-André Lemburg37aa5802002-02-10 21:42:47 +0000669- encodings package: added aliases for all supported IANA character
670 sets
671
Guido van Rossum606fe4e2001-12-28 20:57:14 +0000672- ftplib: to safeguard the user's privacy, anonymous login will use
673 "anonymous@" as default password, rather than the real user and host
674 name.
675
Fred Drake36736122002-01-10 13:50:31 +0000676- webbrowser: tightened up the command passed to os.system() so that
677 arbitrary shell code can't be executed because a bogus URL was
678 passed in.
679
Tim Peters11bd9942002-02-01 00:52:29 +0000680- gettext.translation has an optional fallback argument, and
Martin v. Löwisa55ffae2002-01-11 06:58:49 +0000681 gettext.find an optional all argument. Translations will now fallback
Martin v. Löwisd8996052002-11-21 21:45:32 +0000682 on a per-message basis. The module supports plural forms, by means
683 of gettext.[d]ngettext and Translation.[u]ngettext.
Martin v. Löwis1be64192002-01-11 06:33:28 +0000684
Martin v. Löwis9668b932002-01-12 11:27:42 +0000685- distutils bdist commands now offer a --skip-build option.
686
Walter Dörwaldb25c2b02002-03-21 10:38:40 +0000687- warnings.warn now accepts a Warning instance as first argument.
688
Fred Drakefed7e852002-04-04 19:36:15 +0000689- The xml.sax.expatreader.ExpatParser class will no longer create
690 circular references by using itself as the locator that gets passed
691 to the content handler implementation. [SF bug #535474]
692
Barry Warsaw47f3e2c2002-05-20 00:14:24 +0000693- The email.Parser.Parser class now properly parses strings regardless
694 of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
695 or CRLF). Also, the Header class's constructor default arguments
696 has changed slightly so that an explicit maxlinelen value is always
Barry Warsaw497e5c42002-12-30 19:27:08 +0000697 honored, and so unicode conversion error handling can be specified.
Barry Warsaw47f3e2c2002-05-20 00:14:24 +0000698
Gustavo Niemeyerf8ca8362002-11-05 16:50:05 +0000699- distutils' build_ext command now links c++ extensions with the c++
700 compiler available in the Makefile or CXX environment variable, if
701 running under *nix.
702
703- New module bz2: provides a comprehensive interface for the bz2 compression
704 library. It implements a complete file interface, one-shot (de)compression
705 functions, and types for sequential (de)compression.
706
Barry Warsaw5d8d6182002-11-05 22:41:33 +0000707- New pdb command `pp' which is like `p' except that it pretty-prints
708 the value of its expression argument.
709
Gustavo Niemeyerfbceb012002-11-06 18:44:26 +0000710- Now bdist_rpm distutils command understands a verify_script option in
711 the config file, including the contents of the referred filename in
712 the "%verifyscript" section of the rpm spec file.
713
Gustavo Niemeyer1456fde2002-11-25 17:25:04 +0000714- Fixed bug #495695: webbrowser module would run graphic browsers in a
715 unix environment even if DISPLAY was not set. Also, support for
716 skipstone browser was included.
717
Gustavo Niemeyerd5ae01a2002-12-16 13:11:57 +0000718- Fixed bug #636769: rexec would run unallowed code if subclasses of
719 strings were used as parameters for certain functions.
720
Tim Petersaf8446f2001-12-21 21:36:50 +0000721Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000722-----------
Tim Petersaf8446f2001-12-21 21:36:50 +0000723
Martin v. Löwis0d1fdea2002-11-22 08:36:54 +0000724- pygettext.py now supports globbing on Windows, and accepts module
725 names in addition to accepting file names.
726
Guido van Rossum923e4ef2002-09-17 20:58:59 +0000727- The SGI demos (Demo/sgi) have been removed. Nobody thought they
728 were interesting any more. (The SGI library modules and extensions
729 are still there; it is believed that at least some of these are
730 still used and useful.)
731
Fred Drake40813b12002-08-05 15:24:19 +0000732- IDLE supports the new encoding declarations (PEP 263); it can also
733 deal with legacy 8-bit files if they use the locale's encoding. It
734 allows non-ASCII strings in the interactive shell and executes them
735 in the locale's encoding.
Martin v. Löwis98ce7b72002-08-05 15:11:26 +0000736
Marc-André Lemburg46260092002-04-04 16:17:11 +0000737- freeze.py now produces binaries which can import shared modules,
738 unlike before when this failed due to missing symbol exports in
739 the generated binary.
740
Tim Petersaf8446f2001-12-21 21:36:50 +0000741Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000742-----
Tim Petersaf8446f2001-12-21 21:36:50 +0000743
Guido van Rossumacd738f2002-12-30 21:04:23 +0000744- Makefile.pre.in now adds @CFLAGS@ and @CPPFLAGS@ to their respective
745 variable definitions.
746
Martin v. Löwisdc461752002-11-06 21:59:33 +0000747- On Unix, IDLE is now installed automatically.
748
Guido van Rossum6b3db552002-09-25 15:02:44 +0000749- The fpectl module is not built by default; it's dangerous or useless
750 except in the hands of experts.
751
Tim Petersf47630f2002-08-01 02:34:51 +0000752- The public Python C API will generally be declared using PyAPI_FUNC
Guido van Rossum6b3db552002-09-25 15:02:44 +0000753 and PyAPI_DATA macros, while Python extension module init functions
754 will be declared with PyMODINIT_FUNC. DL_EXPORT/DL_IMPORT macros
755 are deprecated.
Neal Norwitz1389f3e2002-07-22 13:21:10 +0000756
Tim Petersc6a3ff62002-07-08 22:11:52 +0000757- A bug was fixed that could cause COUNT_ALLOCS builds to segfault, or
758 get into infinite loops, when a new-style class got garbage-collected.
759 Unfortunately, to avoid this, the way COUNT_ALLOCS works requires
760 that new-style classes be immortal in COUNT_ALLOCS builds. Note that
761 COUNT_ALLOCS is not enabled by default, in either release or debug
762 builds, and that new-style classes are immortal only in COUNT_ALLOCS
763 builds.
764
Tim Peters943382c2002-07-07 03:59:34 +0000765- Compiling out the cyclic garbage collector is no longer an option.
766 The old symbol WITH_CYCLE_GC is now ignored, and Python.h arranges
767 that it's always defined (for the benefit of any extension modules
768 that may be conditionalizing on it). A bonus is that any extension
769 type participating in cyclic gc can choose to participate in the
770 Py_TRASHCAN mechanism now too; in the absence of cyclic gc, this used
771 to require editing the core to teach the trashcan mechanism about the
772 new type.
773
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +0000774- According to Annex F of the current C standard,
Tim Peters1de41bf2002-07-03 03:31:20 +0000775
776 The Standard C macro HUGE_VAL and its float and long double analogs,
777 HUGE_VALF and HUGE_VALL, expand to expressions whose values are
778 positive infinities.
779
780 Python only uses the double HUGE_VAL, and only to #define its own symbol
781 Py_HUGE_VAL. Some platforms have incorrect definitions for HUGE_VAL.
782 pyport.h used to try to worm around that, but the workarounds triggered
783 other bugs on other platforms, so we gave up. If your platform defines
784 HUGE_VAL incorrectly, you'll need to #define Py_HUGE_VAL to something
785 that works on your platform. The only instance of this I'm sure about
786 is on an unknown subset of Cray systems, described here:
787
788 http://www.cray.com/swpubs/manuals/SN-2194_2.0/html-SN-2194_2.0/x3138.htm
789
790 Presumably 2.3a1 breaks such systems. If anyone uses such a system, help!
791
Martin v. Löwisa3fb4f72002-06-09 13:33:54 +0000792- The configure option --without-doc-strings can be used to remove the
793 doc strings from the builtin functions and modules; this reduces the
794 size of the executable.
795
Guido van Rossumadd88062002-08-15 14:01:14 +0000796- The universal newlines option (PEP 278) is on by default. On Unix
797 it can be disabled by passing --without-universal-newlines to the
798 configure script. On other platforms, remove
799 WITH_UNIVERSAL_NEWLINES from pyconfig.h.
Tim Peters639295f2002-04-21 07:30:30 +0000800
Martin v. Löwis1142de32002-03-29 16:28:31 +0000801- On Unix, a shared libpython2.3.so can be created with --enable-shared.
802
Tim Peters8deda702002-03-30 10:06:07 +0000803- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
804 preprocessor symbols were eliminated. The internal decisions they
805 controlled stopped being experimental long ago.
Tim Peters1f7df352002-03-29 03:29:08 +0000806
Fred Drake7d28b732002-05-02 21:17:00 +0000807- The tools used to build the documentation now work under Cygwin as
808 well as Unix.
809
Skip Montanaro57454e52002-06-14 20:30:31 +0000810- The bsddb and dbm module builds have been changed to try and avoid version
811 skew problems and disable linkage with Berkeley DB 1.85 unless the
812 installer knows what s/he's doing. See the section on building these
813 modules in the README file for details.
814
Tim Petersaf8446f2001-12-21 21:36:50 +0000815C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000816-----
Tim Petersaf8446f2001-12-21 21:36:50 +0000817
Neil Schemenauer6c194762002-11-18 16:19:39 +0000818- PyNumber_Check() now returns true for string and unicode objects.
819 This is a result of these types having a partially defined
Guido van Rossum1d267402002-11-18 16:27:16 +0000820 tp_as_number slot. (This is not a feature, but an indication that
Walter Dörwalda1a61f92002-11-19 21:20:25 +0000821 PyNumber_Check() is not very useful to determine numeric behavior.
Guido van Rossum1d267402002-11-18 16:27:16 +0000822 It may be deprecated.)
Neil Schemenauer6c194762002-11-18 16:19:39 +0000823
Guido van Rossum45ec02a2002-08-19 21:43:18 +0000824- The string object's layout has changed: the pointer member
825 ob_sinterned has been replaced by an int member ob_sstate. On some
826 platforms (e.g. most 64-bit systems) this may change the offset of
827 the ob_sval member, so as a precaution the API_VERSION has been
828 incremented. The apparently unused feature of "indirect interned
829 strings", supported by the ob_sinterned member, is gone. Interned
830 strings are now usually mortal; theres a new API,
831 PyString_InternImmortal() that creates immortal interned strings.
832 (The ob_sstate member can only take three values; however, while
833 making it a char saves a few bytes per string object on average, in
834 it also slowed things down a bit because ob_sval was no longer
835 aligned.)
836
Guido van Rossumfdb86482002-08-14 21:20:32 +0000837- The Py_InitModule*() functions now accept NULL for the 'methods'
838 argument. Modules without global functions are becoming more common
839 now that factories can be types rather than functions.
840
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000841- New C API PyUnicode_FromOrdinal() which exposes unichr() at C
842 level.
843
Thomas Heller085358a2002-07-29 14:27:41 +0000844- New functions PyErr_SetExcFromWindowsErr() and
845 PyErr_SetExcFromWindowsErrWithFilename(). Similar to
846 PyErr_SetFromWindowsErrWithFilename() and
847 PyErr_SetFromWindowsErr(), but they allow to specify
848 the exception type to raise. Available on Windows.
849
Tim Peters7c321a82002-07-09 02:57:01 +0000850- Py_FatalError() is now declared as taking a const char* argument. It
851 was previously declared without const. This should not affect working
852 code.
853
Martin v. Löwis01f94bd2002-05-08 08:44:21 +0000854- Added new macro PySequence_ITEM(o, i) that directly calls
855 sq_item without rechecking that o is a sequence and without
856 adjusting for negative indices.
857
Fred Draked0ba6362002-05-02 21:28:26 +0000858- PyRange_New() now raises ValueError if the fourth argument is not 1.
859 This is part of the removal of deprecated features of the xrange
860 object.
861
Guido van Rossum517c7d42002-04-26 02:49:14 +0000862- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
863 coercion if both arguments have the same type but this type has the
864 CHECKTYPES flag set. This is to better support proxies.
865
Skip Montanaroa2a07bc2002-09-30 15:23:01 +0000866- The type of tp_free has been changed from "``void (*)(PyObject *)``" to
867 "``void (*)(void *)``".
Neil Schemenauer9344b142002-04-12 23:00:08 +0000868
869- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
870
Guido van Rossum0986d822002-04-08 01:38:42 +0000871- A type can now inherit its metatype from its base type. Previously,
872 when PyType_Ready() was called, if ob_type was found to be NULL, it
873 was always set to &PyType_Type; now it is set to base->ob_type,
874 where base is tp_base, defaulting to &PyObject_Type.
875
876- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
877
Neil Schemenauerc9abc1d2002-05-08 14:14:41 +0000878- The PyCore_* family of APIs have been removed.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000879
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000880- The "u#" parser marker will now pass through Unicode objects as-is
Marc-André Lemburg3e3eacb2002-01-09 16:21:27 +0000881 without going through the buffer API.
882
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000883- The enumerators of cmp_op have been renamed to use the prefix ``PyCmp_``.
Martin v. Löwis7198a522002-01-01 19:59:11 +0000884
Tim Peters10a3bb52001-12-25 19:07:38 +0000885- An old #define of ANY as void has been removed from pyport.h. This
886 hasn't been used since Python's pre-ANSI days, and the #define has
887 been marked as obsolete since then. SF bug 495548 says it created
888 conflicts with other packages, so keeping it around wasn't harmless.
889
Tim Petersaf8446f2001-12-21 21:36:50 +0000890- Because Python's magic number scheme broke on January 1st, we decided
891 to stop Python development. Thanks for all the fish!
892
Tim Petersfb05db22002-03-11 00:24:00 +0000893- Some of us don't like fish, so we changed Python's magic number
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000894 scheme to a new one. See Python/import.c for details.
895
Tim Petersaf8446f2001-12-21 21:36:50 +0000896New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000897-------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000898
Martin v. Löwis79acb9e2002-12-06 12:48:53 +0000899- OpenVMS is now supported.
900
Martin v. Löwisf90ae202002-06-11 06:22:31 +0000901- AtheOS is now supported.
902
Andrew MacIntyre161ad0e2002-08-04 07:25:58 +0000903- the EMX runtime environment on OS/2 is now supported.
904
Martin v. Löwisa6e97582002-01-01 18:41:33 +0000905- GNU/Hurd is now supported.
906
Tim Petersaf8446f2001-12-21 21:36:50 +0000907Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000908-----
909
Fred Drake4dd0f7e2002-11-26 21:44:56 +0000910- The regrtest.py script's -u option now provides a way to say "allow
911 all resources except this one." For example, to allow everything
912 except bsddb, give the option '-uall,-bsddb'.
Tim Petersaf8446f2001-12-21 21:36:50 +0000913
914Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000915-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000916
Tim Peters19cf4ee2002-11-23 03:49:08 +0000917- The Windows distribution now ships with version 4.0.14 of the
918 Sleepycat Berkeley database library. This should be a huge
919 improvement over the previous Berkeley DB 1.85, which had many
920 bugs.
921 XXX What are the licensing issues here?
Tim Peters84c7a3f2002-11-23 18:48:06 +0000922 XXX If a user has a database created with a previous verion of
923 XXX Python, what must they do to convert it?
924 XXX I'm still not sure how to link this thing (see PCbuild/readme.txt).
Tim Peters19cf4ee2002-11-23 03:49:08 +0000925 XXX The version # is likely to change before 2.3a1.
Tim Peterse820cb62002-12-16 20:57:22 +0000926
927- The Windows distribution now ships with a Secure Sockets Library (SLL)
Mark Hammondc3de0082002-12-03 06:16:08 +0000928 module (_ssl.pyd)
Tim Peters19cf4ee2002-11-23 03:49:08 +0000929
Tim Peters857fb4c2002-11-14 23:31:58 +0000930- The Windows distribution now ships with Tcl/Tk version 8.4.1 (it
931 previously shipped with Tcl/Tk 8.3.2).
932
Tim Peters37dfb012002-11-11 19:51:33 +0000933- When Python is built under a Microsoft compiler, sys.version now
934 includes the compiler version number (_MSC_VER). For example, under
935 MSVC 6, sys.version constains the substring "MSC v.1200 ". 1200 is
936 the value of _MSC_VER under MSVC 6.
937
Tim Peters08e72952002-04-16 20:48:01 +0000938- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
939 of that has been fixed in the installer (disabled Wise's "delete in-
940 use files" uninstall option).
941
Guido van Rossum181e41a2002-04-06 00:23:25 +0000942- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
943
Tim Peters33187922002-04-04 20:02:04 +0000944- The installer now installs Start menu shortcuts under (the local
945 equivalent of) "All Users" when doing an Admin install.
946
Tim Petersfb05db22002-03-11 00:24:00 +0000947- file.truncate([newsize]) now works on Windows for all newsize values.
948 It used to fail if newsize didn't fit in 32 bits, reflecting a
949 limitation of MS _chsize (which is no longer used).
950
Tim Petersab034fa2002-02-01 11:27:43 +0000951- os.waitpid() is now implemented for Windows, and can be used to block
952 until a specified process exits. This is similar to, but not exactly
953 the same as, os.waitpid() on POSIX systems. If you're waiting for
954 a specific process whose pid was obtained from one of the spawn()
955 functions, the same Python os.waitpid() code works across platforms.
Tim Peters33187922002-04-04 20:02:04 +0000956 See the docs for details. The docs were changed to clarify that
957 spawn functions return, and waitpid requires, a process handle on
958 Windows (not the same thing as a Windows process id).
Tim Petersab034fa2002-02-01 11:27:43 +0000959
Tim Peters11bd9942002-02-01 00:52:29 +0000960- New tempfile.TemporaryFile implementation for Windows: this doesn't
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000961 need a TemporaryFileWrapper wrapper anymore, and should be immune
Tim Peters11bd9942002-02-01 00:52:29 +0000962 to a nasty problem: before 2.3, if you got a temp file on Windows, it
963 got wrapped in an object whose close() method first closed the
964 underlying file, then deleted the file. This usually worked fine.
965 However, the spawn family of functions on Windows create (at a low C
966 level) the same set of open files in the spawned process Q as were
967 open in the spawning process P. If a temp file f was among them, then
968 doing f.close() in P first closed P's C-level file handle on f, but Q's
969 C-level file handle on f remained open, so the attempt in P to delete f
970 blew up with a "Permission denied" error (Windows doesn't allow
971 deleting open files). This was surprising, subtle, and difficult to
972 work around.
973
974- The os module now exports all the symbolic constants usable with the
975 low-level os.open() on Windows: the new constants in 2.3 are
976 O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
977 The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
978 O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
979 to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
980 (so specify both if you want both; note that neither is useful unless
981 specified with O_CREAT too).
982
Tim Petersaf8446f2001-12-21 21:36:50 +0000983Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000984----
985
Jack Jansenae3cb6c2002-12-23 11:25:49 +0000986- Mac/Relnotes is gone, the release notes are now here.
Tim Petersaf8446f2001-12-21 21:36:50 +0000987
Jack Jansenae3cb6c2002-12-23 11:25:49 +0000988- The current naming convention for Python on the Macintosh is that MacPython
989 refers to the unix-based OSX-only version, and MacPython-OS9 refers to the
990 CFM-based version that runs on both OS9 and OSX.
991
992- All MacPython-OS9 functionality is now available in an OSX unix build,
993 including the Carbon modules, the IDE, OSA support, etc. A lot of this
994 will only work correctly in a framework build, though, because you cannot
995 talk to the window manager unless your application is run from a .app
996 bundle. There is a command line tool "pythonw" that runs your script
997 with an interpreter living in such a .app bundle, this interpreter should
998 be used to run any Python script using the window manager (including
999 Tkinter or wxPython scripts).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001000
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001001- A new utility PythonLauncher will start a Python interpreter when a .py or
1002 .pyw script is double-clicked in the Finder. By default .py scripts are
1003 run with a normal Python interpreter in a Terminal window and .pyw
1004 files are run with a window-aware pythonw interpreter without a Terminal
1005 window, but all this can be customized.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001006
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001007- MacPython-OS9 is now Carbon-only, so it runs on Mac OS 9 or Mac OS X and
1008 possibly on Mac OS 8.6 with the right CarbonLib installed, but not on earlier
1009 releases.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001010
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001011- Many tools such as BuildApplet.py and gensuitemodule.py now support a command
1012 line interface too.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001013
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001014- All the Carbon classes are now PEP253 compliant, meaning that you can
1015 subclass them from Python. Most of the attributes have gone, you should
1016 now use the accessor function call API, which is also what Apple's
1017 documentation uses. Some attributes such as grafport.visRgn are still
1018 available for convenience.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001019
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001020- New Carbon modules File (implementing the APIs in Files.h and Aliases.h)
1021 and Folder (APIs from Folders.h). The old macfs builtin module is
1022 gone, and replaced by a Python wrapper around the new modules.
1023
1024- Pathname handling should now be fully consistent: MacPython-OSX always uses
1025 unix pathnames and MacPython-OS9 always uses colon-separated Mac pathnames
1026 (also when running on Mac OS X).
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001027
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001028- New Carbon modules Help and AH give access to the Carbon Help Manager.
1029 There are hooks in the IDE to allow accessing the Python documentation
1030 (and Apple's Carbon and Cocoa documentation) through the Help Viewer.
1031 See Mac/OSX/README for converting the Python documentation to a
1032 Help Viewer comaptible form and installing it.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001033
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001034- OSA support has been redesigned and the generated Python classes now
1035 mirror the inheritance defined by the underlying OSA classes.
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001036
Jack Jansenae3cb6c2002-12-23 11:25:49 +00001037- MacPython no longer maps both \r and \n to \n on input for any text file.
1038 This feature has been replaced by universal newline support (PEP278).
Tim Petersaf8446f2001-12-21 21:36:50 +00001039
Tim Peters909c0912001-12-14 23:16:18 +00001040What's New in Python 2.2 final?
Tim Peters909c0912001-12-14 23:16:18 +00001041===============================
1042
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001043*Release date: 21-Dec-2001*
1044
Tim Peters909c0912001-12-14 23:16:18 +00001045Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001046--------------------------------------------
Tim Peters909c0912001-12-14 23:16:18 +00001047
Barry Warsaw52acb492001-12-21 20:04:22 +00001048- pickle.py, cPickle: allow pickling instances of new-style classes
1049 with a custom metaclass.
1050
Tim Peters909c0912001-12-14 23:16:18 +00001051Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001052-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001053
Barry Warsaw52acb492001-12-21 20:04:22 +00001054- weakref proxy object: when comparing, unwrap both arguments if both
1055 are proxies.
1056
Tim Peters909c0912001-12-14 23:16:18 +00001057Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001058-----------------
Tim Peters909c0912001-12-14 23:16:18 +00001059
Barry Warsaw52acb492001-12-21 20:04:22 +00001060- binascii.b2a_base64(): fix a potential buffer overrun when encoding
1061 very short strings.
1062
1063- cPickle: the obscure "fast" mode was suspected of causing stack
1064 overflows on the Mac. Hopefully fixed this by setting the recursion
1065 limit much smaller. If the limit is too low (it only affects
1066 performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
1067 when compiling cPickle.c (or in pyconfig.h).
1068
Tim Peters909c0912001-12-14 23:16:18 +00001069Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001070-------
Tim Peters909c0912001-12-14 23:16:18 +00001071
Barry Warsaw52acb492001-12-21 20:04:22 +00001072- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
1073 close or delete time).
1074
1075- rfc822.py: fixed a bug where the address '<>' was converted to None
1076 instead of an empty string (also fixes the email.Utils module).
1077
1078- xmlrpclib.py: version 1.0.0; uses precision for doubles.
1079
1080- test suite: the pickle and cPickle tests were not executing any code
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001081 when run from the standard regression test.
Barry Warsaw52acb492001-12-21 20:04:22 +00001082
Tim Peters909c0912001-12-14 23:16:18 +00001083Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001084-----------
Tim Peters909c0912001-12-14 23:16:18 +00001085
1086Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001087-----
Tim Peters909c0912001-12-14 23:16:18 +00001088
1089C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001090-----
Tim Peters909c0912001-12-14 23:16:18 +00001091
1092New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001093-------------
Tim Peters909c0912001-12-14 23:16:18 +00001094
1095Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001096-----
Tim Peters909c0912001-12-14 23:16:18 +00001097
1098Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001099-------
Tim Peters909c0912001-12-14 23:16:18 +00001100
Barry Warsaw52acb492001-12-21 20:04:22 +00001101- distutils package: fixed broken Windows installers (bdist_wininst).
1102
1103- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
1104 instances are deleted at process exit time.
1105
1106- socket.py: prevent mysterious warnings when socket instances are
1107 deleted at process exit time.
1108
1109- posixmodule.c: fix a Windows crash with stat() of a filename ending
1110 in backslash.
1111
Tim Peters909c0912001-12-14 23:16:18 +00001112Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001113----
Tim Peters909c0912001-12-14 23:16:18 +00001114
Barry Warsaw52acb492001-12-21 20:04:22 +00001115- The Carbon toolbox modules have been upgraded to Universal Headers
1116 3.4, and experimental CoreGraphics and CarbonEvents modules have
1117 been added. All only for framework-enabled MacOSX.
1118
Tim Peters909c0912001-12-14 23:16:18 +00001119
Tim Peters6272dfd2001-12-13 19:34:00 +00001120What's New in Python 2.2c1?
Tim Petersb3c9af12001-11-17 00:21:57 +00001121===========================
1122
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001123*Release date: 14-Dec-2001*
1124
Tim Petersb3c9af12001-11-17 00:21:57 +00001125Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001126--------------------------------------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001127
Barry Warsaw06557452001-12-14 20:47:12 +00001128- Guido's tutorial introduction to the new type/class features has
1129 been extensively updated. See
1130
1131 http://www.python.org/2.2/descrintro.html
1132
1133 That remains the primary documentation in this area.
1134
Guido van Rossum33bab012001-12-05 22:45:48 +00001135- Fixed a leak: instance variables declared with __slots__ were never
1136 deleted!
1137
Guido van Rossum4b800852001-12-03 00:54:52 +00001138- The "delete attribute" method of descriptor objects is called
1139 __delete__, not __del__. In previous releases, it was mistakenly
1140 called __del__, which created an unfortunate overloading condition
1141 with finalizers. (The "get attribute" and "set attribute" methods
1142 are still called __get__ and __set__, respectively.)
1143
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001144- Some subtle issues with the super built-in were fixed:
1145
1146 (a) When super itself is subclassed, its __get__ method would still
1147 return an instance of the base class (i.e., of super).
1148
1149 (b) super(C, C()).__class__ would return C rather than super. This
1150 is confusing. To fix this, I decided to change the semantics of
1151 super so that it only applies to code attributes, not to data
1152 attributes. After all, overriding data attributes is not
1153 supported anyway.
1154
1155 (c) The __get__ method didn't check whether the argument was an
1156 instance of the type used in creation of the super instance.
1157
Guido van Rossumcd7b7d62001-12-04 21:02:07 +00001158- Previously, hash() of an instance of a subclass of a mutable type
1159 (list or dictionary) would return some value, rather than raising
1160 TypeError. This has been fixed. Also, directly calling
1161 dict.__hash__ and list.__hash__ now raises the same TypeError
1162 (previously, these were the same as object.__hash__).
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +00001163
Guido van Rossumd331cb52001-12-05 19:46:42 +00001164- New-style objects now support deleting their __dict__. This is for
1165 all intents and purposes equivalent to assigning a brand new empty
1166 dictionary, but saves space if the object is not used further.
1167
Tim Petersb3c9af12001-11-17 00:21:57 +00001168Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001169-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001170
Tim Peters3caca232001-12-06 06:23:26 +00001171- -Qnew now works as documented in PEP 238: when -Qnew is passed on
1172 the command line, all occurrences of "/" use true division instead
1173 of classic division. See the PEP for details. Note that "all"
1174 means all instances in library and 3rd-party modules, as well as in
1175 your own code. As the PEP says, -Qnew is intended for use only in
1176 educational environments with control over the libraries in use.
Tim Petersbf72fe22001-12-11 21:43:14 +00001177 Note that test_coercion.py in the standard Python test suite fails
1178 under -Qnew; this is expected, and won't be repaired until true
1179 division becomes the default (in the meantime, test_coercion is
1180 testing the current rules).
Tim Peters3caca232001-12-06 06:23:26 +00001181
Fred Drake6c01e252001-12-14 17:08:12 +00001182- complex() now only allows the first argument to be a string
1183 argument, and raises TypeError if either the second arg is a string
1184 or if the second arg is specified when the first is a string.
1185
Tim Petersb3c9af12001-11-17 00:21:57 +00001186Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001187-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001188
Martin v. Löwis560da622001-11-24 09:24:51 +00001189- gc.get_referents was renamed to gc.get_referrers.
1190
Tim Petersb3c9af12001-11-17 00:21:57 +00001191Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001192-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001193
Tim Peters25059d32001-12-07 20:35:43 +00001194- Functions in the os.spawn() family now release the global interpreter
1195 lock around calling the platform spawn. They should always have done
1196 this, but did not before 2.2c1. Multithreaded programs calling
1197 an os.spawn function with P_WAIT will no longer block all Python threads
1198 until the spawned program completes. It's possible that some programs
1199 relies on blocking, although more likely by accident than by design.
1200
Martin v. Löwis3a89b2b2001-11-25 14:35:58 +00001201- webbrowser defaults to netscape.exe on OS/2 now.
1202
Martin v. Löwis652e1912001-11-25 14:50:56 +00001203- Tix.ResizeHandle exposes detach_widget, hide, and show.
1204
Martin v. Löwis714d2e22001-12-02 12:26:03 +00001205- The charset alias windows_1252 has been added.
1206
Barry Warsaw06557452001-12-14 20:47:12 +00001207- types.StringTypes is a tuple containing the defined string types;
1208 usually this will be (str, unicode), but if Python was compiled
1209 without Unicode support it will be just (str,).
1210
1211- The pulldom and minidom modules were synchronized to PyXML.
1212
Tim Petersb3c9af12001-11-17 00:21:57 +00001213Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001214-----------
Tim Petersb3c9af12001-11-17 00:21:57 +00001215
Barry Warsaw06557452001-12-14 20:47:12 +00001216- A new script called Tools/scripts/google.py was added, which fires
1217 off a search on Google.
1218
Tim Petersb3c9af12001-11-17 00:21:57 +00001219Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001220-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001221
Barry Warsaw06557452001-12-14 20:47:12 +00001222- Note that release builds of Python should arrange to define the
1223 preprocessor symbol NDEBUG on the command line (or equivalent).
1224 In the 2.2 pre-release series we tried to define this by magic in
1225 Python.h instead, but it proved to cause problems for extension
1226 authors. The Unix, Windows and Mac builds now all define NDEBUG in
1227 release builds via cmdline (or equivalent) instead. Ports to
1228 other platforms should do likewise.
1229
Jack Jansen1999ef42001-12-06 21:47:20 +00001230- It is no longer necessary to use --with-suffix when building on a
1231 case-insensitive file system (such as Mac OS X HFS+). In the build
1232 directory an extension is used, but not in the installed python.
1233
Tim Petersb3c9af12001-11-17 00:21:57 +00001234C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001235-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001236
Tim Petersf582b822001-12-11 18:51:08 +00001237- New function PyDict_MergeFromSeq2() exposes the builtin dict
1238 constructor's logic for updating a dictionary from an iterable object
1239 producing key-value pairs.
1240
Tim Peterscffed4b2001-11-29 03:26:37 +00001241- PyArg_ParseTupleAndKeywords() requires that the number of entries in
Tim Petersf582b822001-12-11 18:51:08 +00001242 the keyword list equal the number of argument specifiers. This
Tim Peterscffed4b2001-11-29 03:26:37 +00001243 wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
1244 dump core in some bad cases. This has been repaired. As a result,
1245 PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
1246 previously went unchallenged.
1247
Tim Petersb3c9af12001-11-17 00:21:57 +00001248New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001249-------------
Tim Petersb3c9af12001-11-17 00:21:57 +00001250
1251Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001252-----
Tim Petersb3c9af12001-11-17 00:21:57 +00001253
1254Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001255-------
Tim Petersb3c9af12001-11-17 00:21:57 +00001256
1257Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001258----
Tim Petersb3c9af12001-11-17 00:21:57 +00001259
Jack Jansenffa260f2001-12-06 21:14:00 +00001260- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
1261 without any trailing digits.
Tim Petersb3c9af12001-11-17 00:21:57 +00001262
Barry Warsaw06557452001-12-14 20:47:12 +00001263- Changed logic for finding python home in Mac OS X framework Pythons.
1264 Now sys.executable points to the executable again, in stead of to
1265 the shared library. The latter is used only for locating the python
1266 home.
1267
1268
Tim Peters84362bc2001-10-19 17:55:30 +00001269What's New in Python 2.2b2?
Tim Peters84362bc2001-10-19 17:55:30 +00001270===========================
1271
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001272*Release date: 16-Nov-2001*
1273
Tim Peters84362bc2001-10-19 17:55:30 +00001274Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001275--------------------------------------------
Tim Peters84362bc2001-10-19 17:55:30 +00001276
Guido van Rossum3d27df02001-11-15 20:27:54 +00001277- Multiple inheritance mixing new-style and classic classes in the
1278 list of base classes is now allowed, so this works now:
Tim Peters76f7fe32001-11-15 20:02:21 +00001279
1280 class Classic: pass
Guido van Rossum3d27df02001-11-15 20:27:54 +00001281 class Mixed(Classic, object): pass
Tim Peters76f7fe32001-11-15 20:02:21 +00001282
1283 The MRO (method resolution order) for each base class is respected
1284 according to its kind, but the MRO for the derived class is computed
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001285 using new-style MRO rules if any base class is a new-style class.
Tim Peters76f7fe32001-11-15 20:02:21 +00001286 This needs to be documented.
1287
Tim Petersa427a2b2001-10-29 22:25:45 +00001288- The new builtin dictionary() constructor, and dictionary type, have
1289 been renamed to dict. This reflects a decade of common usage.
1290
Guido van Rossum3fc08d22001-11-15 20:33:10 +00001291- dict() now accepts an iterable object producing 2-sequences. For
1292 example, dict(d.items()) == d for any dictionary d. The argument,
1293 and the elements of the argument, can be any iterable objects.
1294
Guido van Rossum7ad2d1e2001-10-29 22:11:00 +00001295- New-style classes can now have a __del__ method, which is called
1296 when the instance is deleted (just like for classic classes).
1297
Guido van Rossum12d955c2001-10-26 14:56:06 +00001298- Assignment to object.__dict__ is now possible, for objects that are
1299 instances of new-style classes that have a __dict__ (unless the base
1300 class forbids it).
1301
Guido van Rossumc8e56452001-10-22 00:43:43 +00001302- Methods of built-in types now properly check for keyword arguments
1303 (formerly these were silently ignored). The only built-in methods
1304 that take keyword arguments are __call__, __init__ and __new__.
1305
Guido van Rossum86443212001-10-27 22:28:54 +00001306- The socket function has been converted to a type; see below.
1307
Tim Peters84362bc2001-10-19 17:55:30 +00001308Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001309-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001310
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001311- Assignment to __debug__ raises SyntaxError at compile-time. This
1312 was promised when 2.1c1 was released as "What's New in Python 2.1c1"
Barry Warsaw012852b2001-11-16 16:17:27 +00001313 (see below) says.
Jeremy Hylton249aaed2001-11-09 21:06:24 +00001314
Guido van Rossum12d955c2001-10-26 14:56:06 +00001315- Clarified the error messages for unsupported operands to an operator
1316 (like 1 + '').
1317
Tim Peters84362bc2001-10-19 17:55:30 +00001318Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001319-----------------
Tim Peters84362bc2001-10-19 17:55:30 +00001320
Tim Peters5ebfd362001-11-13 23:11:19 +00001321- mmap has a new keyword argument, "access", allowing a uniform way for
1322 both Windows and Unix users to create read-only, write-through and
1323 copy-on-write memory mappings. This was previously possible only on
1324 Unix. A new keyword argument was required to support this in a
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001325 uniform way because the mmap() signatures had diverged across
Tim Peters5ebfd362001-11-13 23:11:19 +00001326 platforms. Thanks to Jay T Miller for repairing this!
1327
Tim Peters169ded02001-11-03 19:57:21 +00001328- By default, the gc.garbage list now contains only those instances in
1329 unreachable cycles that have __del__ methods; in 2.1 it contained all
1330 instances in unreachable cycles. "Instances" here has been generalized
1331 to include instances of both new-style and old-style classes.
1332
Guido van Rossum12d955c2001-10-26 14:56:06 +00001333- The socket module defines a new method for socket objects,
1334 sendall(). This is like send() but may make multiple calls to
Guido van Rossum86443212001-10-27 22:28:54 +00001335 send() until all data has been sent. Also, the socket function has
1336 been converted to a subclassable type, like list and tuple (etc.)
1337 before it; socket and SocketType are now the same thing.
Guido van Rossum12d955c2001-10-26 14:56:06 +00001338
1339- Various bugfixes to the curses module. There is now a test suite
1340 for the curses module (you have to run it manually).
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001341
Guido van Rossum692adf12001-10-30 03:03:03 +00001342- binascii.b2a_base64 no longer places an arbitrary restriction of 57
1343 bytes on its input.
1344
Tim Peters84362bc2001-10-19 17:55:30 +00001345Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001346-------
Tim Peters84362bc2001-10-19 17:55:30 +00001347
Tim Peters5ebfd362001-11-13 23:11:19 +00001348- tkFileDialog exposes a Directory class and askdirectory
Martin v. Löwis25ee87c2001-11-07 22:38:08 +00001349 convenience function.
1350
Tim Peters75335872001-11-03 19:35:43 +00001351- Symbolic group names in regular expressions must be unique. For
1352 example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
1353 single name can't mean both "group 1" and "group 2" simultaneously.
Barry Warsaw012852b2001-11-16 16:17:27 +00001354 Python 2.2 detects this error at regexp compilation time;
1355 previously, the error went undetected, and results were
1356 unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
1357 pattern.subn() methods have been rewritten in C. Also, an
1358 experimental function/method finditer() has been added, which works
1359 like findall() but returns an iterator.
Tim Peters75335872001-11-03 19:35:43 +00001360
Martin v. Löwisb7b32602001-11-02 23:48:20 +00001361- Tix exposes more commands through the classes DirSelectBox,
1362 DirSelectDialog, ListNoteBook, Meter, CheckList, and the
1363 methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
1364 tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
1365
Tim Peters98791af2001-10-23 01:59:54 +00001366- Traceback objects are now scanned by cyclic garbage collection, so
1367 cycles created by casual use of sys.exc_info() no longer cause
1368 permanent memory leaks (provided garbage collection is enabled).
1369
Guido van Rossum49192142001-10-24 20:51:44 +00001370- os.extsep -- a new variable needed by the RISCOS support. It is the
1371 separator used by extensions, and is '.' on all platforms except
1372 RISCOS, where it is '/'. There is no need to use this variable
1373 unless you have a masochistic desire to port your code to RISCOS.
1374
Barry Warsaw012852b2001-11-16 16:17:27 +00001375- mimetypes.py has optional support for non-standard, but commonly
1376 found types. guess_type() and guess_extension() now accept an
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001377 optional 'strict' flag, defaulting to true, which controls whether
Barry Warsaw012852b2001-11-16 16:17:27 +00001378 recognize non-standard types or not. A few non-standard types we
1379 know about have been added. Also, when run as a script, there are
1380 new -l and -e options.
1381
1382- statcache is now deprecated.
1383
1384- email.Utils.formatdate() now produces the preferred RFC 2822 style
1385 dates with numeric timezones (it used to produce obsolete dates
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001386 hard coded to "GMT" timezone). An optional 'localtime' flag is
Barry Warsaw012852b2001-11-16 16:17:27 +00001387 added to produce dates in the local timezone, with daylight savings
1388 time properly taken into account.
1389
1390- In pickle and cPickle, instead of masking errors in load() by
1391 transforming them into SystemError, we let the original exception
1392 propagate out. Also, implement support for __safe_for_unpickling__
1393 in pickle, as it already was supported in cPickle.
1394
Tim Peters84362bc2001-10-19 17:55:30 +00001395Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001396-----------
Tim Peters84362bc2001-10-19 17:55:30 +00001397
1398Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001399-----
Tim Peters84362bc2001-10-19 17:55:30 +00001400
Barry Warsaw012852b2001-11-16 16:17:27 +00001401- The dbm module is built using libdb1 if available. The bsddb module
1402 is built with libdb3 if available.
1403
1404- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
1405
Tim Peters84362bc2001-10-19 17:55:30 +00001406C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001407-----
Tim Peters84362bc2001-10-19 17:55:30 +00001408
Tim Peters1fc240e2001-10-26 05:06:50 +00001409- New function PySequence_Fast_GET_SIZE() returns the size of a non-
1410 NULL result from PySequence_Fast(), more quickly than calling
1411 PySequence_Size().
1412
Barry Warsaw012852b2001-11-16 16:17:27 +00001413- New argument unpacking function PyArg_UnpackTuple() added.
1414
1415- New functions PyObject_CallFunctionObjArgs() and
1416 PyObject_CallMethodObjArgs() have been added to make it more
1417 convenient and efficient to call functions and methods from C.
1418
1419- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
1420 possible that this will propagate errors it didn't before.
1421
1422- New function PyObject_CheckReadBuffer(), which returns true if its
1423 argument supports the single-segment readable buffer interface.
1424
Tim Peters84362bc2001-10-19 17:55:30 +00001425New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001426-------------
Tim Peters84362bc2001-10-19 17:55:30 +00001427
Guido van Rossum86443212001-10-27 22:28:54 +00001428- We've finally confirmed that this release builds on HP-UX 11.00,
1429 *with* threads, and passes the test suite.
1430
Tim Peters7a33d8b2001-11-05 02:51:07 +00001431- Thanks to a series of patches from Michael Muller, Python may build
1432 again under OS/2 Visual Age C++.
1433
Guido van Rossum49192142001-10-24 20:51:44 +00001434- Updated RISCOS port by Dietmar Schwertberger.
1435
Tim Peters84362bc2001-10-19 17:55:30 +00001436Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001437-----
Tim Peters84362bc2001-10-19 17:55:30 +00001438
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001439- Added a test script for the curses module. It isn't run automatically;
1440 regrtest.py must be run with '-u curses' to enable it.
1441
Tim Peters84362bc2001-10-19 17:55:30 +00001442Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001443-------
Tim Peters84362bc2001-10-19 17:55:30 +00001444
Barry Warsaw012852b2001-11-16 16:17:27 +00001445Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001446----
Barry Warsaw012852b2001-11-16 16:17:27 +00001447
1448- PythonScript has been moved to unsupported and is slated to be
1449 removed completely in the next release.
1450
1451- It should now be possible to build applets that work on both OS9 and
1452 OSX.
1453
1454- The core is now linked with CoreServices not Carbon; as a side
1455 result, default 8bit encoding on OSX is now ASCII.
1456
1457- Python should now build on OSX 10.1.1
1458
Tim Peters84362bc2001-10-19 17:55:30 +00001459
Tim Petersabf925f2001-09-28 21:53:42 +00001460What's New in Python 2.2b1?
Tim Petersabf925f2001-09-28 21:53:42 +00001461===========================
1462
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001463*Release date: 19-Oct-2001*
1464
Tim Petersabf925f2001-09-28 21:53:42 +00001465Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001466--------------------------------------------
Tim Petersabf925f2001-09-28 21:53:42 +00001467
Guido van Rossum687ae002001-10-15 22:03:32 +00001468- New-style classes are now always dynamic (except for built-in and
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001469 extension types). There is no longer a performance penalty, and I
Guido van Rossum687ae002001-10-15 22:03:32 +00001470 no longer see another reason to keep this baggage around. One relic
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001471 remains: the __dict__ of a new-style class is a read-only proxy; you
1472 must set the class's attribute to modify it. As a consequence, the
Guido van Rossum687ae002001-10-15 22:03:32 +00001473 __defined__ attribute of new-style types no longer exists, for lack
1474 of need: there is once again only one __dict__ (although in the
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001475 future a __cache__ may be resurrected with a similar function, if I
1476 can prove that it actually speeds things up).
Guido van Rossum50fda3b2001-10-04 19:46:06 +00001477
Tim Peters1c9ca872001-10-04 06:43:12 +00001478- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
1479 always returned None, even when there was a class docstring).
1480
1481- doctest now finds and runs docstrings attached to new-style classes,
1482 class methods, static methods, and properties.
1483
Guido van Rossum9074ef62001-10-16 21:34:49 +00001484Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001485-----------------
Tim Petersabf925f2001-09-28 21:53:42 +00001486
Guido van Rossuma8bcf802001-10-15 15:53:58 +00001487- A very subtle syntactical pitfall in list comprehensions was fixed.
1488 For example: [a+b for a in 'abc', for b in 'def']. The comma in
1489 this example is a mistake. Previously, this would silently let 'a'
1490 iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
1491 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
1492 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
1493 Note that [a for a in <singleton>] is a convoluted way to say
1494 [<singleton>] anyway, so it's not like any expressiveness is lost.
1495
Guido van Rossum9074ef62001-10-16 21:34:49 +00001496- getattr(obj, name, default) now only catches AttributeError, as
1497 documented, rather than returning the default value for all
1498 exceptions (which could mask bugs in a __getattr__ hook, for
1499 example).
1500
Fred Drakecb7a6b52001-10-22 18:41:51 +00001501- Weak reference objects are now part of the core and offer a C API.
Fred Drake934d2a42001-10-18 18:18:06 +00001502 A bug which could allow a core dump when binary operations involved
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001503 proxy reference has been fixed. weakref.ReferenceError is now a
Barry Warsawf6fb1712001-10-19 05:35:40 +00001504 built-in exception.
Fred Drake934d2a42001-10-18 18:18:06 +00001505
Guido van Rossum1c486092001-10-19 02:05:35 +00001506- unicode(obj) now behaves more like str(obj), accepting arbitrary
1507 objects, and calling a __unicode__ method if it exists.
1508 unicode(obj, encoding) and unicode(obj, encoding, errors) still
Marc-André Lemburgb5507ec2001-10-19 12:02:29 +00001509 require an 8-bit string or character buffer argument.
Guido van Rossum1c486092001-10-19 02:05:35 +00001510
Barry Warsawf6fb1712001-10-19 05:35:40 +00001511- isinstance() now allows any object as the first argument and a
1512 class, a type or something with a __bases__ tuple attribute for the
1513 second argument. The second argument may also be a tuple of a
1514 class, type, or something with __bases__, in which case isinstance()
1515 will return true if the first argument is an instance of any of the
1516 things contained in the second argument tuple. E.g.
1517
1518 isinstance(x, (A, B))
1519
1520 returns true if x is an instance of A or B.
1521
Guido van Rossum9074ef62001-10-16 21:34:49 +00001522Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001523-----------------
Guido van Rossum9074ef62001-10-16 21:34:49 +00001524
1525- thread.start_new_thread() now returns the thread ID (previously None).
1526
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001527- binascii has now two quopri support functions, a2b_qp and b2a_qp.
1528
Guido van Rossumc524d952001-10-19 01:31:59 +00001529- readline now supports setting the startup_hook and the
1530 pre_event_hook, and adds the add_history() function.
Martin v. Löwis0daad592001-09-30 21:09:59 +00001531
Guido van Rossumc524d952001-10-19 01:31:59 +00001532- os and posix supports chroot(), setgroups() and unsetenv() where
1533 available. The stat(), fstat(), statvfs() and fstatvfs() functions
1534 now return "pseudo-sequences" -- the various fields can now be
1535 accessed as attributes (e.g. os.stat("/").st_mtime) but for
1536 backwards compatibility they also behave as a fixed-length sequence.
1537 Some platform-specific fields (e.g. st_rdev) are only accessible as
Guido van Rossum98bf58f2001-10-18 20:34:25 +00001538 attributes.
1539
1540- time: localtime(), gmtime() and strptime() now return a
1541 pseudo-sequence similar to the os.stat() return value, with
1542 attributes like tm_year etc.
Martin v. Löwis16628c92001-10-04 22:46:41 +00001543
Guido van Rossum9074ef62001-10-16 21:34:49 +00001544- Decompression objects in the zlib module now accept an optional
1545 second parameter to decompress() that specifies the maximum amount
1546 of memory to use for the uncompressed data.
Tim Petersabf925f2001-09-28 21:53:42 +00001547
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001548- optional SSL support in the socket module now exports OpenSSL
1549 functions RAND_add(), RAND_egd(), and RAND_status(). These calls
1550 are useful on platforms like Solaris where OpenSSL does not
Barry Warsawf6fb1712001-10-19 05:35:40 +00001551 automatically seed its PRNG. Also, the keyfile and certfile
1552 arguments to socket.ssl() are now optional.
1553
1554- posixmodule (and by extension, the os module on POSIX platforms) now
1555 exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001556
Guido van Rossum9074ef62001-10-16 21:34:49 +00001557Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001558-------
Guido van Rossum3c288632001-10-16 21:13:49 +00001559
Tim Peters7402f792001-10-02 03:53:41 +00001560- doctest now excludes functions and classes not defined by the module
1561 being tested, thanks to Tim Hochberg.
1562
Fred Drakecb7a6b52001-10-22 18:41:51 +00001563- HotShot, a new profiler implemented using a C-based callback, has
1564 been added. This substantially reduces the overhead of profiling,
1565 but it is still quite preliminary. Support modules and
1566 documentation will be added in upcoming releases (before 2.2 final).
1567
Guido van Rossumc4b09b42001-10-04 10:19:00 +00001568- profile now produces correct output in situations where an exception
1569 raised in Python is cleared by C code (e.g. hasattr()). This used
1570 to cause wrong output, including spurious claims of recursive
1571 functions and attribution of time spent to the wrong function.
1572
Tim Peters0a1fc4e2001-10-07 03:12:08 +00001573 The code and documentation for the derived OldProfile and HotProfile
1574 profiling classes was removed. The code hasn't worked for years (if
1575 you tried to use them, they raised exceptions). OldProfile
1576 intended to reproduce the behavior of the profiler Python used more
1577 than 7 years ago, and isn't interesting anymore. HotProfile intended
1578 to provide a faster profiler (but producing less information), and
1579 that's a worthy goal we intend to meet via a different approach (but
1580 without losing information).
1581
Tim Peterscce092d2001-10-09 05:31:56 +00001582- Profile.calibrate() has a new implementation that should deliver
Tim Peters659a6032001-10-09 20:51:19 +00001583 a much better system-specific calibration constant. The constant can
1584 now be specified in an instance constructor, or as a Profile class or
1585 instance variable, instead of by editing profile.py's source code.
1586 Calibration must still be done manually (see the docs for the profile
1587 module).
1588
1589 Note that Profile.calibrate() must be overriden by subclasses.
1590 Improving the accuracy required exploiting detailed knowledge of
1591 profiler internals; the earlier method abstracted away the details
1592 and measured a simplified model instead, but consequently computed
1593 a constant too small by a factor of 2 on some modern machines.
Tim Peterscce092d2001-10-09 05:31:56 +00001594
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001595- quopri's encode and decode methods take an optional header parameter,
Jeremy Hylton6f543b62001-10-16 20:42:52 +00001596 which indicates whether output is intended for the header 'Q'
1597 encoding.
1598
Guido van Rossuma5343cc2001-10-18 18:02:07 +00001599- The SocketServer.ThreadingMixIn class now closes the request after
1600 finish_request() returns. (Not when it errors out though.)
1601
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001602- The nntplib module's NNTP.body() method has grown a 'file' argument
Barry Warsawf6fb1712001-10-19 05:35:40 +00001603 to allow saving the message body to a file.
1604
1605- The email package has added a class email.Parser.HeaderParser which
1606 only parses headers and does not recurse into the message's body.
1607 Also, the module/class MIMEAudio has been added for representing
1608 audio data (contributed by Anthony Baxter).
1609
1610- ftplib should be able to handle files > 2GB.
1611
1612- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
1613 ON, and OFF.
1614
Fred Drakecb7a6b52001-10-22 18:41:51 +00001615- xml.dom.minidom NodeList objects now support the length attribute
1616 and item() method as required by the DOM specifications.
1617
Guido van Rossumed554f62001-10-02 23:15:37 +00001618Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001619-----------
Guido van Rossumed554f62001-10-02 23:15:37 +00001620
1621- Demo/dns was removed. It no longer serves any purpose; a package
1622 derived from it is now maintained by Anthony Baxter, see
1623 http://PyDNS.SourceForge.net.
Tim Petersabf925f2001-09-28 21:53:42 +00001624
Barry Warsawf6fb1712001-10-19 05:35:40 +00001625- The freeze tool has been made more robust, and two new options have
1626 been added: -X and -E.
1627
Tim Petersabf925f2001-09-28 21:53:42 +00001628Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001629-----
Tim Petersabf925f2001-09-28 21:53:42 +00001630
Barry Warsawf6fb1712001-10-19 05:35:40 +00001631- configure will use CXX in LINKCC if CXX is used to build main() and
1632 the system requires to link a C++ main using the C++ compiler.
1633
Tim Petersabf925f2001-09-28 21:53:42 +00001634C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001635-----
Tim Petersabf925f2001-09-28 21:53:42 +00001636
Guido van Rossum6c4bce32001-10-18 19:20:25 +00001637- The documentation for the tp_compare slot is updated to require that
1638 the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
1639 not correct. This is not yet enforced but will be enforced in
1640 Python 2.3; even later, we may use -2 to indicate errors and +2 for
1641 "NotImplemented". Right now, -1 should be used for an error return.
1642
Tim Petersd38b1c72001-09-30 05:09:37 +00001643- PyLong_AsLongLong() now accepts int (as well as long) arguments.
1644 Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
1645 as long) arguments.
1646
Guido van Rossum3c288632001-10-16 21:13:49 +00001647- PyThread_start_new_thread() now returns a long int giving the thread
1648 ID, if one can be calculated; it returns -1 for error, 0 if no
1649 thread ID is calculated (this is an incompatible change, but only
1650 the thread module used this API). This code has only really been
1651 tested on Linux and Windows; other platforms please beware (and
1652 report any bugs or strange behavior).
1653
Guido van Rossum1c486092001-10-19 02:05:35 +00001654- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
1655 input.
1656
Tim Petersabf925f2001-09-28 21:53:42 +00001657New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001658-------------
Tim Petersabf925f2001-09-28 21:53:42 +00001659
1660Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001661-----
Tim Petersabf925f2001-09-28 21:53:42 +00001662
1663Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001664-------
Tim Petersabf925f2001-09-28 21:53:42 +00001665
Tim Peters04cf1d32001-10-09 22:39:40 +00001666- Installer: If you install IDLE, and don't disable file-extension
1667 registration, a new "Edit with IDLE" context (right-click) menu entry
1668 is created for .py and .pyw files.
1669
Tim Peters1ce3cf72001-10-01 17:58:40 +00001670- The signal module now supports SIGBREAK on Windows, thanks to Steven
1671 Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
1672 action remains to call Win32 ExitProcess(). This can be changed via
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00001673 signal.signal(). For example::
Tim Peters1ce3cf72001-10-01 17:58:40 +00001674
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001675 # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
1676 # (SIGINT) behavior.
1677 import signal
1678 signal.signal(signal.SIGBREAK, signal.default_int_handler)
Tim Peters1ce3cf72001-10-01 17:58:40 +00001679
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001680 try:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001681 while 1:
1682 pass
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001683 except KeyboardInterrupt:
Raymond Hettingeraf72d522002-12-29 20:14:11 +00001684 # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
1685 # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
1686 # program without the possibility for any Python-level cleanup).
1687 print "Clean exit"
Tim Peters1ce3cf72001-10-01 17:58:40 +00001688
Tim Petersabf925f2001-09-28 21:53:42 +00001689
Tim Petersb07352e2001-09-08 01:25:47 +00001690What's New in Python 2.2a4?
1691===========================
1692
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001693*Release date: 28-Sep-2001*
1694
Guido van Rossum808eea72001-09-25 04:15:41 +00001695Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001696--------------------------------------------
Guido van Rossum808eea72001-09-25 04:15:41 +00001697
1698- pydoc and inspect are now aware of new-style classes;
1699 e.g. help(list) at the interactive prompt now shows proper
1700 documentation for all operations on list objects.
1701
1702- Applications using Jim Fulton's ExtensionClass module can now safely
1703 be used with Python 2.2. In particular, Zope 2.4.1 now works with
1704 Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
1705 examples also work again. It is hoped that Gtk and Boost also work
1706 with 2.2a4 and beyond. (If you can confirm this, please write
1707 webmaster@python.org; if there are still problems, please open a bug
1708 report on SourceForge.)
Tim Petersb07352e2001-09-08 01:25:47 +00001709
Tim Peters66c1a522001-09-24 21:17:50 +00001710- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001711 These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
Tim Peters66c1a522001-09-24 21:17:50 +00001712 in the constructed property object. fget, fset and fdel weren't
1713 discoverable from Python in 2.2a3. __doc__ is new, and allows to
1714 associate a docstring with a property.
1715
Guido van Rossum808eea72001-09-25 04:15:41 +00001716- Comparison overloading is now more completely implemented. For
1717 example, a str subclass instance can properly be compared to a str
1718 instance, and it can properly overload comparison. Ditto for most
1719 other built-in object types.
1720
1721- The repr() of new-style classes has changed; instead of <type
1722 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
1723 *except* for built-in types, which are still rendered as <type
1724 'Foo'> (to avoid upsetting existing code that might parse or
1725 otherwise rely on repr() of certain type objects).
1726
1727- The repr() of new-style objects is now always <Foo object at XXX>;
1728 previously, it was sometimes <Foo instance at XXX>.
1729
1730- For new-style classes, what was previously called __getattr__ is now
1731 called __getattribute__. This method, if defined, is called for
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001732 *every* attribute access. A new __getattr__ hook more similar to the
Guido van Rossum808eea72001-09-25 04:15:41 +00001733 one in classic classes is defined which is called only if regular
1734 attribute access raises AttributeError; to catch *all* attribute
1735 access, you can use __getattribute__ (for new-style classes). If
1736 both are defined, __getattribute__ is called first, and if it raises
1737 AttributeError, __getattr__ is called.
1738
1739- The __class__ attribute of new-style objects can be assigned to.
1740 The new class must have the same C-level object layout as the old
1741 class.
1742
1743- The builtin file type can be subclassed now. In the usual pattern,
1744 "file" is the name of the builtin type, and file() is a new builtin
1745 constructor, with the same signature as the builtin open() function.
1746 file() is now the preferred way to open a file.
1747
1748- Previously, __new__ would only see sequential arguments passed to
1749 the type in a constructor call; __init__ would see both sequential
1750 and keyword arguments. This made no sense whatsoever any more, so
1751 now both __new__ and __init__ see all arguments.
1752
1753- Previously, hash() applied to an instance of a subclass of str or
1754 unicode always returned 0. This has been repaired.
1755
1756- Previously, an operation on an instance of a subclass of an
1757 immutable type (int, long, float, complex, tuple, str, unicode),
1758 where the subtype didn't override the operation (and so the
1759 operation was handled by the builtin type), could return that
1760 instance instead a value of the base type. For example, if s was of
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001761 a str subclass type, s[:] returned s as-is. Now it returns a str
Guido van Rossum808eea72001-09-25 04:15:41 +00001762 with the same value as s.
1763
Barry Warsaw86fbaf82001-09-28 15:26:12 +00001764- Provisional support for pickling new-style objects has been added.
1765
Guido van Rossum808eea72001-09-25 04:15:41 +00001766Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001767----
Guido van Rossum808eea72001-09-25 04:15:41 +00001768
Tim Peters2c9aa5e2001-09-23 04:06:05 +00001769- file.writelines() now accepts any iterable object producing strings.
1770
Marc-André Lemburgaefd7662001-09-20 12:59:37 +00001771- PyUnicode_FromEncodedObject() now works very much like
1772 PyObject_Str(obj) in that it tries to use __str__/tp_str
1773 on the object if the object is not a string or buffer. This
1774 makes unicode() behave like str() when applied to non-string/buffer
1775 objects.
1776
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001777- PyFile_WriteObject now passes Unicode objects to the file's write
1778 method. As a result, all file-like objects which may be the target
Martin v. Löwis2777c022001-09-19 13:47:32 +00001779 of a print statement must support Unicode objects, i.e. they must
1780 at least convert them into ASCII strings.
1781
Guido van Rossum624c8af2001-09-18 15:21:04 +00001782- Thread scheduling on Solaris should be improved; it is no longer
1783 necessary to insert a small sleep at the start of a thread in order
1784 to let other runnable threads be scheduled.
1785
Tim Petersb07352e2001-09-08 01:25:47 +00001786Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001787-------
Tim Petersb07352e2001-09-08 01:25:47 +00001788
Marc-André Lemburgbf990172001-09-27 14:17:33 +00001789- StringIO.StringIO instances and cStringIO.StringIO instances support
1790 read character buffer compatible objects for their .write() methods.
1791 These objects are converted to strings and then handled as such
1792 by the instances.
1793
Barry Warsaw2f600732001-09-24 04:28:10 +00001794- The "email" package has been added. This is basically a port of the
1795 mimelib package <http://sf.net/projects/mimelib> with API changes
1796 and some implementations updated to use iterators and generators.
1797
Tim Peters8a9c2842001-09-22 21:30:22 +00001798- difflib.ndiff() and difflib.Differ.compare() are generators now. This
1799 restores the ability of Tools/scripts/ndiff.py to start producing output
1800 before the entire comparison is complete.
1801
Barry Warsaw58b072d2001-09-22 04:44:21 +00001802- StringIO.StringIO instances and cStringIO.StringIO instances support
1803 iteration just like file objects (i.e. their .readline() method is
1804 called for each iteration until it returns an empty string).
1805
Marc-André Lemburg494f2ae2001-09-19 11:33:31 +00001806- The codecs module has grown four new helper APIs to access
1807 builtin codecs: getencoder(), getdecoder(), getreader(),
1808 getwriter().
1809
Guido van Rossum624c8af2001-09-18 15:21:04 +00001810- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
1811 simplifies writing XML RPC servers.
1812
Barry Warsaw647d5e82001-09-28 17:01:02 +00001813- os.path.realpath(): a new function that returns the absolute pathname
Guido van Rossum624c8af2001-09-18 15:21:04 +00001814 after interpretation of symbolic links. On non-Unix systems, this
1815 is an alias for os.path.abspath().
1816
Tim Peters16a77ad2001-09-08 04:00:12 +00001817- operator.indexOf() (PySequence_Index() in the C API) now works with any
1818 iterable object.
1819
Guido van Rossum624c8af2001-09-18 15:21:04 +00001820- smtplib now supports various authentication and security features of
1821 the SMTP protocol through the new login() and starttls() methods.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00001822
Guido van Rossum624c8af2001-09-18 15:21:04 +00001823- hmac: a new module implementing keyed hashing for message
1824 authentication.
1825
1826- mimetypes now recognizes more extensions and file types. At the
1827 same time, some mappings not sanctioned by IANA were removed.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00001828
Guido van Rossum624c8af2001-09-18 15:21:04 +00001829- The "compiler" package has been brought up to date to the state of
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00001830 Python 2.2 bytecode generation. It has also been promoted from a
1831 Tool to a standard library package. (Tools/compiler still exists as
1832 a sample driver.)
1833
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00001834Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001835-----
Guido van Rossum624c8af2001-09-18 15:21:04 +00001836
Tim Petersb07352e2001-09-08 01:25:47 +00001837Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001838-----
Tim Petersb07352e2001-09-08 01:25:47 +00001839
Guido van Rossum624c8af2001-09-18 15:21:04 +00001840- Large file support (LFS) is now automatic when the platform supports
1841 it; no more manual configuration tweaks are needed. On Linux, at
1842 least, it's possible to have a system whose C library supports large
1843 files but whose kernel doesn't; in this case, large file support is
1844 still enabled but doesn't do you any good unless you upgrade your
1845 kernel or share your Python executable with another system whose
1846 kernel has large file support.
1847
1848- The configure script now supplies plausible defaults in a
1849 cross-compilation environment. This doesn't mean that the supplied
1850 values are always correct, or that cross-compilation now works
1851 flawlessly -- but it's a first step (and it shuts up most of
1852 autoconf's warnings about AC_TRY_RUN).
1853
1854- The Unix build is now a bit less chatty, courtesy of the parser
1855 generator. The build is completely silent (except for errors) when
1856 using "make -s", thanks to a -q option to setup.py.
1857
Tim Petersb07352e2001-09-08 01:25:47 +00001858C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001859-----
Tim Petersb07352e2001-09-08 01:25:47 +00001860
Guido van Rossum624c8af2001-09-18 15:21:04 +00001861- The "structmember" API now supports some new flag bits to deny read
1862 and/or write access to attributes in restricted execution mode.
1863
Tim Petersb07352e2001-09-08 01:25:47 +00001864New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001865-------------
Tim Petersb07352e2001-09-08 01:25:47 +00001866
Guido van Rossum624c8af2001-09-18 15:21:04 +00001867- Compaq's iPAQ handheld, running the "familiar" Linux distribution
1868 (http://familiar.handhelds.org).
1869
Tim Petersb07352e2001-09-08 01:25:47 +00001870Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001871-----
Tim Petersb07352e2001-09-08 01:25:47 +00001872
Tim Peters8a9c2842001-09-22 21:30:22 +00001873- The "classic" standard tests, which work by comparing stdout to
1874 an expected-output file under Lib/test/output/, no longer stop at
1875 the first mismatch. Instead the test is run to completion, and a
1876 variant of ndiff-style comparison is used to report all differences.
1877 This is much easier to understand than the previous style of reporting.
1878
1879- The unittest-based standard tests now use regrtest's test_main()
1880 convention, instead of running as a side-effect of merely being
1881 imported. This allows these tests to be run in more natural and
1882 flexible ways as unittests, outside the regrtest framework.
1883
1884- regrtest.py is much better integrated with unittest and doctest now,
1885 especially in regard to reporting errors.
1886
Tim Petersb07352e2001-09-08 01:25:47 +00001887Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001888-------
Tim Petersb07352e2001-09-08 01:25:47 +00001889
Guido van Rossum624c8af2001-09-18 15:21:04 +00001890- Large file support now also works for files > 4GB, on filesystems
Tim Peters8a9c2842001-09-22 21:30:22 +00001891 that support it (NTFS under Windows 2000). See "What's New in
1892 Python 2.2a3" for more detail.
Guido van Rossum624c8af2001-09-18 15:21:04 +00001893
Tim Petersb07352e2001-09-08 01:25:47 +00001894
Tim Petersedc99312001-08-22 21:36:50 +00001895What's New in Python 2.2a3?
1896===========================
1897
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001898*Release Date: 07-Sep-2001*
1899
Tim Petersedc99312001-08-22 21:36:50 +00001900Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001901----
Tim Petersedc99312001-08-22 21:36:50 +00001902
Tim Peters9fffa3e2001-09-04 05:14:19 +00001903- Conversion of long to float now raises OverflowError if the long is too
1904 big to represent as a C double.
1905
Tim Peters32f453e2001-09-03 08:35:41 +00001906- The 3-argument builtin pow() no longer allows a third non-None argument
1907 if either of the first two arguments is a float, or if both are of
1908 integer types and the second argument is negative (in which latter case
1909 the arguments are converted to float, so this is really the same
1910 restriction).
1911
Tim Peters5d2b77c2001-09-03 05:47:38 +00001912- The builtin dir() now returns more information, and sometimes much
1913 more, generally naming all attributes of an object, and all attributes
1914 reachable from the object via its class, and from its class's base
1915 classes, and so on from them too. Example: in 2.2a2, dir([]) returned
1916 an empty list. In 2.2a3,
1917
1918 >>> dir([])
1919 ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
1920 '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
1921 '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
1922 '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
1923 '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
1924 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
1925 'reverse', 'sort']
1926
1927 dir(module) continues to return only the module's attributes, though.
1928
Tim Petersbdee63f2001-09-02 03:40:59 +00001929- Overflowing operations on plain ints now return a long int rather
Guido van Rossumae457142001-08-31 18:31:35 +00001930 than raising OverflowError. This is a partial implementation of PEP
1931 237. You can use -Wdefault::OverflowWarning to enable a warning for
1932 this situation, and -Werror::OverflowWarning to revert to the old
1933 OverflowError exception.
1934
Guido van Rossum61c345f2001-09-04 03:26:15 +00001935- A new command line option, -Q<arg>, is added to control run-time
Guido van Rossumae457142001-08-31 18:31:35 +00001936 warnings for the use of classic division. (See PEP 238.) Possible
Barry Warsawd6c8ca62001-09-07 18:13:44 +00001937 values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
1938 -Qold, meaning the / operator has its classic meaning and no
1939 warnings are issued. Using -Qwarn issues a run-time warning about
1940 all uses of classic division for int and long arguments; -Qwarnall
1941 also warns about classic division for float and complex arguments
Tim Peters3caca232001-12-06 06:23:26 +00001942 (for use with fixdiv.py).
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001943 [Note: the remainder of this item (preserved below) became
1944 obsolete in 2.2c1 -- -Qnew has global effect in 2.2] ::
1945
1946 Using -Qnew is questionable; it turns on new division by default, but
1947 only in the __main__ module. You can usefully combine -Qwarn or
1948 -Qwarnall and -Qnew: this gives the __main__ module new division, and
1949 warns about classic division everywhere else.
Guido van Rossumae457142001-08-31 18:31:35 +00001950
Tim Petersbdee63f2001-09-02 03:40:59 +00001951- Many built-in types can now be subclassed. This applies to int,
Guido van Rossumae457142001-08-31 18:31:35 +00001952 long, float, str, unicode, and tuple. (The types complex, list and
1953 dictionary can also be subclassed; this was introduced earlier.)
1954 Note that restrictions apply when subclassing immutable built-in
1955 types: you can only affect the value of the instance by overloading
1956 __new__. You can add mutable attributes, and the subclass instances
1957 will have a __dict__ attribute, but you cannot change the "value"
1958 (as implemented by the base class) of an immutable subclass instance
1959 once it is created.
1960
Guido van Rossumaaf80c82001-09-02 13:44:35 +00001961- The dictionary constructor now takes an optional argument, a
1962 mapping-like object, and initializes the dictionary from its
1963 (key, value) pairs.
1964
Tim Petersbdee63f2001-09-02 03:40:59 +00001965- A new built-in type, super, has been added. This facilitates making
Guido van Rossumae457142001-08-31 18:31:35 +00001966 "cooperative super calls" in a multiple inheritance setting. For an
1967 explanation, see http://www.python.org/2.2/descrintro.html#cooperation
1968
Guido van Rossum8d7234d2001-09-06 22:02:58 +00001969- A new built-in type, property, has been added. This enables the
1970 creation of "properties". These are attributes implemented by
1971 getter and setter functions (or only one of these for read-only or
1972 write-only attributes), without the need to override __getattr__.
1973 See http://www.python.org/2.2/descrintro.html#property
Guido van Rossumae457142001-08-31 18:31:35 +00001974
Tim Petersbdee63f2001-09-02 03:40:59 +00001975- The syntax of floating-point and imaginary literals has been
Tim Petersd507dab2001-08-30 20:51:59 +00001976 liberalized, to allow leading zeroes. Examples of literals now
1977 legal that were SyntaxErrors before:
1978
1979 00.0 0e3 0100j 07.5 00000000000000000008.
1980
Tim Petersbdee63f2001-09-02 03:40:59 +00001981- An old tokenizer bug allowed floating point literals with an incomplete
Tim Petersc6d95812001-08-28 20:56:27 +00001982 exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
1983
Tim Petersedc99312001-08-22 21:36:50 +00001984Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001985-------
Tim Petersedc99312001-08-22 21:36:50 +00001986
Martin v. Löwiscb227c92001-09-06 08:54:16 +00001987- telnetlib includes symbolic names for the options, and support for
Martin v. Löwis1da9c572002-11-04 09:56:00 +00001988 setting an option negotiation callback. It also supports processing
1989 of suboptions.
Martin v. Löwiscb227c92001-09-06 08:54:16 +00001990
Tim Petersa40c7932001-09-05 22:36:56 +00001991- The new C standard no longer requires that math libraries set errno to
1992 ERANGE on overflow. For platform libraries that exploit this new
1993 freedom, Python's overflow-checking was wholly broken. A new overflow-
1994 checking scheme attempts to repair that, but may not be reliable on all
1995 platforms (C doesn't seem to provide anything both useful and portable
1996 in this area anymore).
1997
Martin v. Löwis44f86962001-09-05 13:44:54 +00001998- Asynchronous timeout actions are available through the new class
1999 threading.Timer.
2000
Tim Peters78526162001-09-05 00:53:45 +00002001- math.log and math.log10 now return sensible results for even huge
2002 long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
2003
Tim Petersbdee63f2001-09-02 03:40:59 +00002004- A new function, imp.lock_held(), returns 1 when the import lock is
Tim Peters69232342001-08-30 05:16:13 +00002005 currently held. See the docs for the imp module.
2006
Tim Petersbdee63f2001-09-02 03:40:59 +00002007- pickle, cPickle and marshal on 32-bit platforms can now correctly read
Tim Peters82112372001-08-29 02:28:42 +00002008 dumps containing ints written on platforms where Python ints are 8 bytes.
2009 When read on a box where Python ints are 4 bytes, such values are
2010 converted to Python longs.
2011
Tim Petersbdee63f2001-09-02 03:40:59 +00002012- In restricted execution mode (using the rexec module), unmarshalling
Guido van Rossumae457142001-08-31 18:31:35 +00002013 code objects is no longer allowed. This plugs a security hole.
2014
Steve Purcell6091cd62001-09-06 16:05:17 +00002015- unittest.TestResult instances no longer store references to tracebacks
2016 generated by test failures. This prevents unexpected dangling references
2017 to objects that should be garbage collected between tests.
2018
Tim Petersedc99312001-08-22 21:36:50 +00002019Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002020-----
Tim Petersedc99312001-08-22 21:36:50 +00002021
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002022- Tools/scripts/fixdiv.py has been added which can be used to fix
2023 division operators as per PEP 238.
2024
Tim Petersedc99312001-08-22 21:36:50 +00002025Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002026-----
Tim Petersedc99312001-08-22 21:36:50 +00002027
Barry Warsawd6c8ca62001-09-07 18:13:44 +00002028- If you are an adventurous person using Mac OS X you may want to look at
2029 Mac/OSX. There is a Makefile there that will build Python as a real Mac
2030 application, which can be used for experimenting with Carbon or Cocoa.
2031 Discussion of this on pythonmac-sig, please.
2032
Tim Peters7eea37e2001-09-04 22:08:56 +00002033C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002034-----
Tim Peters7eea37e2001-09-04 22:08:56 +00002035
2036- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
Tim Peters69232342001-08-30 05:16:13 +00002037
Tim Peters9fffa3e2001-09-04 05:14:19 +00002038- Note that PyLong_AsDouble can fail! This has always been true, but no
2039 callers checked for it. It's more likely to fail now, because overflow
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002040 errors are properly detected now. The proper way to check::
Tim Peters9fffa3e2001-09-04 05:14:19 +00002041
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002042 double x = PyLong_AsDouble(some_long_object);
2043 if (x == -1.0 && PyErr_Occurred()) {
Raymond Hettingeraf72d522002-12-29 20:14:11 +00002044 /* The conversion failed. */
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002045 }
Tim Peters9fffa3e2001-09-04 05:14:19 +00002046
Tim Petersbdee63f2001-09-02 03:40:59 +00002047- The GC API has been changed. Extensions that use the old API will still
Neil Schemenauer4042c692001-08-30 15:38:01 +00002048 compile but will not participate in GC. To upgrade an extension
2049 module:
2050
2051 - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
Tim Petersd507dab2001-08-30 20:51:59 +00002052
Neil Schemenauer4042c692001-08-30 15:38:01 +00002053 - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
2054 PyObject_GC_Del to deallocate them
Tim Petersd507dab2001-08-30 20:51:59 +00002055
Neil Schemenauer4042c692001-08-30 15:38:01 +00002056 - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
2057 to PyObject_GC_UnTrack
Tim Petersd507dab2001-08-30 20:51:59 +00002058
Neil Schemenauer4042c692001-08-30 15:38:01 +00002059 - remove PyGC_HEAD_SIZE from object size calculations
2060
2061 - remove calls to PyObject_AS_GC and PyObject_FROM_GC
2062
Tim Petersbdee63f2001-09-02 03:40:59 +00002063- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
Guido van Rossumae457142001-08-31 18:31:35 +00002064 These can be used safely to construct string objects from a
2065 sprintf-style format string (similar to the format string supported
2066 by PyErr_Format()).
Tim Peters69232342001-08-30 05:16:13 +00002067
Tim Petersedc99312001-08-22 21:36:50 +00002068New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002069-------------
Tim Petersedc99312001-08-22 21:36:50 +00002070
Tim Petersb7da0902001-09-02 23:01:43 +00002071- Stephen Hansen contributed patches sufficient to get a clean compile
2072 under Borland C (Windows), but he reports problems running it and ran
2073 out of time to complete the port. Volunteers? Expect a MemoryError
2074 when importing the types module; this is probably shallow, and
2075 causing later failures too.
Tim Petersbdee63f2001-09-02 03:40:59 +00002076
Tim Petersedc99312001-08-22 21:36:50 +00002077Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002078-----
Tim Petersedc99312001-08-22 21:36:50 +00002079
2080Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002081-------
Tim Petersedc99312001-08-22 21:36:50 +00002082
Tim Peters6e13a562001-09-06 00:32:15 +00002083- Large file support is now enabled on Win32 platforms as well as on
2084 Win64. This means that, for example, you can use f.tell() and f.seek()
2085 to manipulate files larger than 2 gigabytes (provided you have enough
2086 disk space, and are using a Windows filesystem that supports large
Tim Peters9a9471c2001-09-11 23:18:51 +00002087 partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
2088 filesize limit, and large file support makes no difference there.
2089 FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
2090 NTFS has no practical limit on file size, and files of any size can be
2091 used from Python now.
Tim Peters6e13a562001-09-06 00:32:15 +00002092
Tim Petersbdee63f2001-09-02 03:40:59 +00002093- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
Tim Peters402d5982001-08-27 06:37:48 +00002094 points to command.com (patch from Brian Quinlan).
2095
Tim Petersedc99312001-08-22 21:36:50 +00002096
Tim Peters20f51a72001-07-21 02:31:40 +00002097What's New in Python 2.2a2?
2098===========================
2099
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002100*Release Date: 22-Aug-2001*
2101
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002102Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002103-----
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002104
Barry Warsaw18b2ecf2001-08-22 20:26:56 +00002105- Tim Peters developed a brand new Windows installer using Wise 8.1,
2106 generously donated to us by Wise Solutions.
2107
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002108- configure supports a new option --enable-unicode, with the values
2109 ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
2110 type and supporting code is completely removed from the interpreter.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002111
Jack Jansen32ce0cd2001-08-21 19:28:20 +00002112- A new configure option --enable-framework builds a Mac OS X framework,
2113 which "make frameworkinstall" will install. This provides a starting
2114 point for more mac-like functionality, join pythonmac-sig@python.org
2115 if you are interested in helping.
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002116
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002117- The NeXT platform is no longer supported.
2118
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002119- The 'new' module is now statically linked.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002120
Tim Peters0afb6092001-08-15 06:06:44 +00002121Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002122-----
Tim Peters0afb6092001-08-15 06:06:44 +00002123
2124- The new Tools/scripts/cleanfuture.py can be used to automatically
Andrew M. Kuchlingb0532092001-08-15 15:54:56 +00002125 edit out obsolete future statements from Python source code. See
Tim Peters0afb6092001-08-15 06:06:44 +00002126 the module docstring for details.
2127
Tim Peters20f51a72001-07-21 02:31:40 +00002128Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002129-----
Tim Peters20f51a72001-07-21 02:31:40 +00002130
Tim Peters5e824c32001-08-12 22:25:01 +00002131- regrtest.py now knows which tests are expected to be skipped on some
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002132 platforms, allowing to give clearer test result output. regrtest
2133 also has optional --use/-u switch to run normally disabled tests
2134 which require network access or consume significant disk resources.
Tim Peters5e824c32001-08-12 22:25:01 +00002135
Tim Peters20f51a72001-07-21 02:31:40 +00002136- Several new tests in the standard test suite, with special thanks to
2137 Nick Mathewson.
2138
2139Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002140----
Tim Peters20f51a72001-07-21 02:31:40 +00002141
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002142- The floor division operator // has been added as outlined in PEP
2143 238. The / operator still provides classic division (and will until
2144 Python 3.0) unless "from __future__ import division" is included, in
2145 which case the / operator will provide true division. The operator
2146 module provides truediv() and floordiv() functions. Augmented
2147 assignment variants are included, as are the equivalent overloadable
2148 methods and C API methods. See the PEP for a full discussion:
2149 <http://python.sf.net/peps/pep-0238.html>
2150
Tim Peters6cd6a822001-08-17 22:11:27 +00002151- Future statements are now effective in simulated interactive shells
2152 (like IDLE). This should "just work" by magic, but read Michael
2153 Hudson's "Future statements in simulated shells" PEP 264 for full
2154 details: <http://python.sf.net/peps/pep-0264.html>.
2155
Guido van Rossumf86ddd22001-08-17 21:21:04 +00002156- The type/class unification (PEP 252-253) was integrated into the
2157 trunk and is not so tentative any more (the exact specification of
2158 some features is still tentative). A lot of work has done on fixing
2159 bugs and adding robustness and features (performance still has to
2160 come a long way).
2161
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002162- Warnings about a mismatch in the Python API during extension import
2163 now use the Python warning framework (which makes it possible to
2164 write filters for these warnings).
2165
Barry Warsaw9b3be7f2001-08-14 18:35:02 +00002166- A function's __dict__ (aka func_dict) will now always be a
2167 dictionary. It used to be possible to delete it or set it to None,
2168 but now both actions raise TypeErrors. It is still legal to set it
2169 to a dictionary object. Getting func.__dict__ before any attributes
2170 have been assigned now returns an empty dictionary instead of None.
2171
Guido van Rossum32aa5d22001-09-05 18:43:35 +00002172- A new command line option, -E, was added which disables the use of
2173 all environment variables, or at least those that are specifically
2174 significant to Python. Usually those have a name starting with
2175 "PYTHON". This was used to fix a problem where the tests fail if
2176 the user happens to have PYTHONHOME or PYTHONPATH pointing to an
2177 older distribution.
2178
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002179Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002180-------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002181
Tim Peters5e824c32001-08-12 22:25:01 +00002182- New class Differ and new functions ndiff() and restore() in difflib.py.
2183 These package the algorithms used by the popular Tools/scripts/ndiff.py,
Tim Peters0afb6092001-08-15 06:06:44 +00002184 for programmatic reuse.
Tim Peters5e824c32001-08-12 22:25:01 +00002185
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002186- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
2187 value using the minimal quoting required for the value; more
2188 reliable than using xml.sax.saxutils.escape() for attribute values.
2189
2190- Readline completion support for cmd.Cmd was added.
2191
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002192- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
2193
2194- Added function threading.BoundedSemaphore()
2195
2196- Added Ka-Ping Yee's cgitb.py module.
2197
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002198- The 'new' module now exposes the CO_xxx flags.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00002199
Martin v. Löwis560da622001-11-24 09:24:51 +00002200- The gc module offers the get_referents function.
2201
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002202New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002203-------------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002204
2205C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002206-----
Marc-André Lemburgd6277912001-07-31 14:42:42 +00002207
Marc-André Lemburg888fac02001-07-31 14:24:31 +00002208- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
2209 which provide a cross-platform implementations for the
2210 relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
2211 the standard sprintf() and vsprintf() C lib APIs, these versions
2212 apply bounds checking on the used buffer which enhances protection
2213 against buffer overruns.
2214
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002215- Unicode APIs now use name mangling to assure that mixing interpreters
Tim Petersc1731372001-08-04 08:12:36 +00002216 and extensions using different Unicode widths is rendered next to
2217 impossible. Trying to import an incompatible Unicode-aware extension
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00002218 will result in an ImportError. Unicode extensions writers must make
2219 sure to check the Unicode width compatibility in their extensions by
2220 using at least one of the mangled Unicode APIs in the extension.
2221
Martin v. Löwis339d0f72001-08-17 18:39:25 +00002222- Two new flags METH_NOARGS and METH_O are available in method definition
2223 tables to simplify implementation of methods with no arguments and a
2224 single untyped argument. Calling such methods is more efficient than
2225 calling corresponding METH_VARARGS methods. METH_OLDARGS is now
2226 deprecated.
2227
Tim Petersc1731372001-08-04 08:12:36 +00002228Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002229-------
Tim Petersc1731372001-08-04 08:12:36 +00002230
2231- "import module" now compiles module.pyw if it exists and nothing else
2232 relevant is found.
2233
Tim Peters20f51a72001-07-21 02:31:40 +00002234
Guido van Rossum55a78992001-07-17 17:22:32 +00002235What's New in Python 2.2a1?
Tim Petersf553f892001-05-01 20:45:31 +00002236===========================
2237
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002238*Release date: 18-Jul-2001*
2239
Tim Petersf553f892001-05-01 20:45:31 +00002240Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002241----
Tim Petersa814db52001-05-14 07:05:58 +00002242
Tim Peters6d6c1a32001-08-02 04:15:00 +00002243- TENTATIVELY, a large amount of code implementing much of what's
2244 described in PEP 252 (Making Types Look More Like Classes) and PEP
2245 253 (Subtyping Built-in Types) was added. This will be released
2246 with Python 2.2a1. Documentation will be provided separately
2247 through http://www.python.org/2.2/. The purpose of releasing this
2248 with Python 2.2a1 is to test backwards compatibility. It is
2249 possible, though not likely, that a decision is made not to release
2250 this code as part of 2.2 final, if any serious backwards
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002251 incompatibilities are found during alpha testing that cannot be
Tim Peters6d6c1a32001-08-02 04:15:00 +00002252 repaired.
2253
Guido van Rossum55a78992001-07-17 17:22:32 +00002254- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +00002255 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +00002256 more 'yield' statements. See PEP 255. Since this adds a new
2257 keyword to the language, this feature must be enabled by including a
2258 future statement: "from __future__ import generators" (see PEP 236).
2259 Generators will become a standard feature in a future release
2260 (probably 2.3). Without this future statement, 'yield' remains an
2261 ordinary identifier, but a warning is issued each time it is used.
2262 (These warnings currently don't conform to the warnings framework of
2263 PEP 230; we intend to fix this in 2.2a2.)
2264
Marc-André Lemburg12e74b32001-05-22 08:58:23 +00002265- The UTF-16 codec was modified to be more RFC compliant. It will now
2266 only remove BOM characters at the start of the string and then
2267 only if running in native mode (UTF-16-LE and -BE won't remove a
2268 leading BMO character).
2269
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002270- Strings now have a new method .decode() to complement the already
2271 existing .encode() method. These two methods provide direct access
2272 to the corresponding decoders and encoders of the registered codecs.
2273
2274 To enhance the usability of the .encode() method, the special
2275 casing of Unicode object return values was dropped (Unicode objects
2276 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +00002277
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002278 Both methods will now return whatever the codec in charge of the
2279 requested encoding returns as object, e.g. Unicode codecs will
2280 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
2281 will return u"äöü"). This enables codec writer to create codecs
2282 for various simple to use conversions.
2283
2284 New codecs were added to demonstrate these new features (the .encode()
2285 and .decode() columns indicate the type of the returned objects):
2286
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002287 +---------+-----------+-----------+-----------------------------+
2288 |Name | .encode() | .decode() | Description |
2289 +=========+===========+===========+=============================+
2290 |uu | string | string | UU codec (e.g. for email) |
2291 +---------+-----------+-----------+-----------------------------+
2292 |base64 | string | string | base64 codec |
2293 +---------+-----------+-----------+-----------------------------+
2294 |quopri | string | string | quoted-printable codec |
2295 +---------+-----------+-----------+-----------------------------+
2296 |zlib | string | string | zlib compression |
2297 +---------+-----------+-----------+-----------------------------+
2298 |hex | string | string | 2-byte hex codec |
2299 +---------+-----------+-----------+-----------------------------+
2300 |rot-13 | string | Unicode | ROT-13 Unicode charmap codec|
2301 +---------+-----------+-----------+-----------------------------+
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00002302
Mark Hammond2a0af792001-05-14 03:09:36 +00002303- Some operating systems now support the concept of a default Unicode
2304 encoding for file system operations. Notably, Windows supports 'mbcs'
2305 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002306 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +00002307 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002308
2309 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +00002310 functions that return filenames (such as os.listdir()) to return Python
2311 string objects pre-encoded using the default file system encoding for
2312 the platform. As this encoding is likely to be different from Python's
2313 default encoding, converting this name to a Unicode object before passing
2314 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +00002315 would attempt to use its default encoding (generally ASCII) rather than
2316 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00002317
Tim Petersa814db52001-05-14 07:05:58 +00002318 In general, this change simply removes surprises when working with
2319 Unicode and the file system, making these operations work as you expect,
2320 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +00002321 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +00002322
Tim Peters61dff2b2001-05-08 15:43:37 +00002323- Float (and complex) literals in source code were evaluated to full
2324 precision only when running from a .py file; the same code loaded from a
2325 .pyc (or .pyo) file could suffer numeric differences starting at about the
2326 12th significant decimal digit. For example, on a machine with IEEE-754
2327 floating arithmetic,
2328
2329 x = 9007199254740992.0
2330 print long(x)
2331
2332 printed 9007199254740992 if run directly from .py, but 9007199254740000
2333 if from a compiled (.pyc or .pyo) file. This was due to marshal using
2334 str(float) instead of repr(float) when building code objects. marshal
2335 now uses repr(float) instead, which should reproduce floats to full
2336 machine precision (assuming the platform C float<->string I/O conversion
2337 functions are of good quality).
2338
2339 This may cause floating-point results to change in some cases, and
2340 usually for the better, but may also cause numerically unstable
2341 algorithms to break.
2342
Tim Peters2f228e72001-05-13 00:19:31 +00002343- The implementation of dicts suffers fewer collisions, which has speed
2344 benefits. However, the order in which dict entries appear in dict.keys(),
2345 dict.values() and dict.items() may differ from previous releases for a
2346 given dict. Nothing is defined about this order, so no program should
2347 rely on it. Nevertheless, it's easy to write test cases that rely on the
2348 order by accident, typically because of printing the str() or repr() of a
2349 dict to an "expected results" file. See Lib/test/test_support.py's new
2350 sortdict(dict) function for a simple way to display a dict in sorted
2351 order.
2352
Tim Peters7a3bfc32001-06-12 01:22:22 +00002353- Many other small changes to dicts were made, resulting in faster
2354 operation along the most common code paths.
2355
Guido van Rossum10315822001-05-01 20:54:30 +00002356- Dictionary objects now support the "in" operator: "x in dict" means
2357 the same as dict.has_key(x).
2358
Barry Warsaw51acc8d2001-06-26 20:12:50 +00002359- The update() method of dictionaries now accepts generic mapping
2360 objects. Specifically the argument object must support the .keys()
2361 and __getitem__() methods. This allows you to say, for example,
2362 {}.update(UserDict())
2363
Guido van Rossum10315822001-05-01 20:54:30 +00002364- Iterators were added; this is a generalized way of providing values
2365 to a for loop. See PEP 234. There's a new built-in function iter()
2366 to return an iterator. There's a new protocol to get the next value
2367 from an iterator using the next() method (in Python) or the
2368 tp_iternext slot (in C). There's a new protocol to get iterators
2369 using the __iter__() method (in Python) or the tp_iter slot (in C).
2370 Iterating (i.e. a for loop) over a dictionary generates its keys.
2371 Iterating over a file generates its lines.
2372
Tim Petersf553f892001-05-01 20:45:31 +00002373- The following functions were generalized to work nicely with iterator
Skip Montanaroa2a07bc2002-09-30 15:23:01 +00002374 arguments::
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002375
Tim Peterse63415e2001-05-08 04:38:29 +00002376 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +00002377 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
2378 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +00002379 join() method of strings
2380 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +00002381 'x in y' and 'x not in y' (PySequence_Contains() in C API)
2382 operator.countOf() (PySequence_Count() in C API)
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002383 right-hand side of assignment statements with multiple targets, such as ::
Tim Petersd6d010b2001-06-21 02:49:55 +00002384 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +00002385
Tim Petersd85e1022001-05-11 21:51:48 +00002386- Accessing module attributes is significantly faster (for example,
2387 random.random or os.path or yourPythonModule.yourAttribute).
2388
Tim Peterse63415e2001-05-08 04:38:29 +00002389- Comparing dictionary objects via == and != is faster, and now works even
2390 if the keys and values don't support comparisons other than ==.
2391
Tim Peters95bf9392001-05-10 08:32:44 +00002392- Comparing dictionaries in ways other than == and != is slower: there were
2393 insecurities in the dict comparison implementation that could cause Python
2394 to crash if the element comparison routines for the dict keys and/or
2395 values mutated the dicts. Making the code bulletproof slowed it down.
2396
Tim Peterseb28ef22001-06-02 05:27:19 +00002397- Collisions in dicts are resolved via a new approach, which can help
2398 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +00002399 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +00002400 faster now. Thanks to Christian Tismer for pointing out the cause and
2401 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +00002402
Tim Peters52e155e2001-06-16 05:42:57 +00002403- repr() is much faster for large containers (dict, list, tuple).
2404
2405
Tim Petersa814db52001-05-14 07:05:58 +00002406Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002407-------
Tim Petersa814db52001-05-14 07:05:58 +00002408
Fred Drake960fdf92001-07-20 18:38:26 +00002409- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002410 were added to the string module. These a locale-independent
Fred Drake960fdf92001-07-20 18:38:26 +00002411 constants, unlike letters, lowercase, and uppercase. These are now
2412 use in appropriate locations in the standard library.
2413
Martin v. Löwisf0473d52001-07-18 16:17:16 +00002414- The flags used in dlopen calls can now be configured using
2415 sys.setdlopenflags and queried using sys.getdlopenflags.
2416
Guido van Rossumc7e4aca2001-07-12 11:54:37 +00002417- Fredrik Lundh's xmlrpclib is now a standard library module. This
2418 provides full client-side XML-RPC support. In addition,
2419 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
2420 one asyncore-based). Thanks to Eric Raymond for the documentation.
2421
Guido van Rossum643d3912001-07-05 14:46:25 +00002422- The xrange() object is simplified: it no longer supports slicing,
2423 repetition, comparisons, efficient 'in' checking, the tolist()
2424 method, or the start, stop and step attributes. See PEP 260.
2425
Martin v. Löwisebf94db2001-06-06 06:25:40 +00002426- A new function fnmatch.filter to filter lists of file names was added.
2427
Barry Warsawffd674d2001-05-22 16:00:10 +00002428- calendar.py uses month and day names based on the current locale.
2429
Guido van Rossum2e0a6542001-05-15 02:14:44 +00002430- strop is now *really* obsolete (this was announced before with 1.6),
2431 and issues DeprecationWarning when used (except for the four items
2432 that are still imported into string.py).
2433
Tim Petersa814db52001-05-14 07:05:58 +00002434- Cookie.py now sorts key+value pairs by key in output strings.
2435
2436- pprint.isrecursive(object) didn't correctly identify recursive objects.
2437 Now it does.
2438
Tim Peters95b3f782001-05-14 18:39:41 +00002439- pprint functions now much faster for large containers (tuple, list, dict).
2440
Tim Peters7b9542a2001-06-10 23:40:19 +00002441- New 'q' and 'Q' format codes in the struct module, corresponding to C
2442 types "long long" and "unsigned long long" (on Windows, __int64). In
2443 native mode, these can be used only when the platform C compiler supports
2444 these types (when HAVE_LONG_LONG is #define'd by the Python config
2445 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +00002446 In standard mode, 'q' and 'Q' are supported on all platforms, and are
2447 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +00002448
Guido van Rossum83213cc2001-06-12 16:48:52 +00002449- The site module installs a new built-in function 'help' that invokes
2450 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
2451 it displays a message reminding the user to use 'help()' or
2452 'help(object)'.
2453
Tim Petersa814db52001-05-14 07:05:58 +00002454Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002455-----
Tim Petersa814db52001-05-14 07:05:58 +00002456
2457- New test_mutants.py runs dict comparisons where the key and value
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002458 comparison operators mutate the dicts randomly during comparison. This
Tim Petersa814db52001-05-14 07:05:58 +00002459 rapidly causes Python to crash under earlier releases (not for the faint
2460 of heart: it can also cause Win9x to freeze or reboot!).
2461
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002462- New test_pprint.py verifies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +00002463 pprint.isreadable() return sensible results. Also verifies that simple
2464 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +00002465
Tim Peters4324aa32001-05-28 22:30:08 +00002466C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002467-----
Tim Peters4324aa32001-05-28 22:30:08 +00002468
2469- Removed the unused last_is_sticky argument from the internal
2470 _PyTuple_Resize(). If this affects you, you were cheating.
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002471
2472----
2473
2474**(For information about older versions, consult the HISTORY file.)**