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Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001+++++++++++
2Python News
3+++++++++++
4
Tim Petersaf8446f2001-12-21 21:36:50 +00005What's New in Python 2.3 alpha 1?
Tim Petersaf8446f2001-12-21 21:36:50 +00006=================================
7
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00008*XXX Release date: DD-MMM-2002 XXX*
9
Tim Petersaf8446f2001-12-21 21:36:50 +000010Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +000011--------------------------------------------
Tim Petersaf8446f2001-12-21 21:36:50 +000012
Guido van Rossume3438782002-08-12 03:42:03 +000013- Assignment to __class__ is disallowed if either the old and the new
14 class is a statically allocated type object (such as defined by an
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +000015 extension module). This prevents anomalies like 2.__class__ = bool.
Guido van Rossume3438782002-08-12 03:42:03 +000016
17- New-style object creation and deallocation have been sped up
18 significantly; they are now faster than classic instance creation
19 and deallocation.
20
21- The __slots__ variable can now mention "private" names, and the
22 right thing will happen (e.g. __slots__ = ["__foo"]).
23
24- The built-ins slice() and buffer() are now callable types. The
25 types classobj (formerly class), code, function, instance, and
26 instancemethod (formerly instance-method), which have no built-in
27 names but are accessible through the types module, are now also
28 callable. The type dict-proxy is renamed to dictproxy.
29
30- Cycles going through the __class__ link of a new-style instance are
31 now detected by the garbage collector.
32
33- Classes using __slots__ are now properly garbage collected.
34 [SF bug 519621]
35
36- Tightened the __slots__ rules: a slot name must be a valid Python
37 identifier.
38
39- The constructor for the module type now requires a name argument and
40 takes an optional docstring argument. Previously, this constructor
41 ignored its arguments. As a consequence, deriving a class from a
42 module (not from the module type) is now illegal; previously this
43 created an unnamed module, just like invoking the module type did.
44 [SF bug 563060]
45
46- A new type object, 'basestring', is added. This is a common base type
47 for 'str' and 'unicode', and can be used instead of
48 types.StringTypes, e.g. to test whether something is "a string":
49 isinstance(x, basestring) is True for Unicode and 8-bit strings. This
50 is an abstract base class and cannot be instantiated directly.
51
52- Changed new-style class instantiation so that when C's __new__
53 method returns something that's not a C instance, its __init__ is
54 not called. [SF bug #537450]
55
56- Fixed super() to work correctly with class methods. [SF bug #535444]
57
58- If you try to pickle an instance of a class that has __slots__ but
59 doesn't define or override __getstate__, a TypeError is now raised.
60 This is done by adding a bozo __getstate__ to the class that always
61 raises TypeError. (Before, this would appear to be pickled, but the
62 state of the slots would be lost.)
63
Tim Petersaf8446f2001-12-21 21:36:50 +000064Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +000065-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +000066
Walter Dörwald3aeb6322002-09-02 13:14:32 +000067- Codec error handling callbacks (PEP 293) are implemented.
68 Error handling in unicode.encode or str.decode can now be customized.
69
Guido van Rossum45ec02a2002-08-19 21:43:18 +000070- A subtle change to the semantics of the built-in function intern():
71 interned strings are no longer immortal. You must keep a reference
72 to the return value intern() around to get the benefit.
73
Guido van Rossumf808b892002-08-16 03:38:10 +000074- Use of 'None' as a variable, argument or attribute name now
75 issues a SyntaxWarning. In the future, None may become a keyword.
76
Michael W. Hudsondd32a912002-08-15 14:59:02 +000077- SET_LINENO is gone. co_lnotab is now consulted to determine when to
78 call the trace function. C code that accessed f_lineno should call
79 PyCode_Addr2Line instead (f_lineno is still there, but not kept up
80 to date).
81
Guido van Rossum9be89462002-08-14 16:11:30 +000082- There's a new warning category, FutureWarning. This is used to warn
83 about a number of situations where the value or sign of an integer
84 result will change in Python 2.4 as a result of PEP 237 (integer
85 unification). The warnings implement stage B0 mentioned in that
86 PEP. The warnings are about the following situations:
87
88 - Octal and hex literals without 'L' prefix in the inclusive range
89 [0x80000000..0xffffffff]; these are currently negative ints, but
90 in Python 2.4 they will be positive longs with the same bit
91 pattern.
92
93 - Left shifts on integer values that cause the outcome to lose
94 bits or have a different sign than the left operand. To be
95 precise: x<<n where this currently doesn't yield the same value
96 as long(x)<<n; in Python 2.4, the outcome will be long(x)<<n.
97
98 - Conversions from ints to string that show negative values as
99 unsigned ints in the inclusive range [0x80000000..0xffffffff];
100 this affects the functions hex() and oct(), and the string
101 formatting codes %u, %o, %x, and %X. In Python 2.4, these will
102 show signed values (e.g. hex(-1) currently returns "0xffffffff";
103 in Python 2.4 it will return "-0x1").
104
Skip Montanaro979c74b2002-09-03 21:25:14 +0000105 - The bits manipulated under the cover by sys.setcheckinterval() have
106 been changed. Both the check interval and the ticker used to be
107 per-thread values. They are now just a pair of global variables. In
108 addition, the default check interval was boosted from 10 to 100
Neal Norwitz7165af22002-09-05 21:42:24 +0000109 bytecode instructions. This may have some effect on systems that
110 relied on the old default value. In particular, in multi-threaded
111 applications which try to be highly responsive, response time will
112 increase by some (perhaps imperceptible) amount.
Skip Montanaro979c74b2002-09-03 21:25:14 +0000113
Tim Petersd64c1de2002-08-12 17:36:03 +0000114- When multiplying very large integers, a version of the so-called
115 Karatsuba algorithm is now used. This is most effective if the
116 inputs have roughly the same size. If they both have about N digits,
117 Karatsuba multiplication has O(N**1.58) runtime (the exponent is
118 log_base_2(3)) instead of the previous O(N**2). Measured results may
Tim Peters012c0a32002-08-16 03:40:07 +0000119 be better or worse than that, depending on platform quirks. Besides
120 the O() improvement in raw instruction count, the Karatsuba algorithm
121 appears to have much better cache behavior on extremely large integers
122 (starting in the ballpark of a million bits). Note that this is a
123 simple implementation, and there's no intent here to compete with,
124 e.g., GMP. It gives a very nice speedup when it applies, but a package
125 devoted to fast large-integer arithmetic should run circles around it.
Tim Peters5af4e6c2002-08-12 02:31:19 +0000126
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000127- u'%c' will now raise a ValueError in case the argument is an
128 integer outside the valid range of Unicode code point ordinals.
129
Guido van Rossumdeb09362002-08-09 17:16:30 +0000130- The tempfile module has been overhauled for enhanced security. The
131 mktemp() function is now deprecated; new, safe replacements are
132 mkstemp() (for files) and mkdtemp() (for directories), and the
133 higher-level functions NamedTemporaryFile() and TemporaryFile().
134 Use of some global variables in this module is also deprecated; the
135 new functions have keyword arguments to provide the same
136 functionality. All Lib, Tools and Demo modules that used the unsafe
137 interfaces have been updated to use the safe replacements. Thanks
138 to Zack Weinberg!
139
Guido van Rossumd81a9832002-08-09 15:57:34 +0000140- When x is an object whose class implements __mul__ and __rmul__,
141 1.0*x would correctly invoke __rmul__, but 1*x would erroneously
142 invoke __mul__. This was due to the sequence-repeat code in the int
143 type. This has been fixed now.
144
Barry Warsawd79f6832002-08-06 17:01:51 +0000145- Previously, "str1 in str2" required str1 to be a string of length 1.
146 This restriction has been relaxed to allow str1 to be a string of
147 any length. Thus "'el' in 'hello world'" returns True now.
148
Guido van Rossumb57089c2002-08-06 16:20:26 +0000149- File objects are now their own iterators. For a file f, iter(f) now
150 returns f (unless f is closed), and f.next() is similar to
151 f.readline() when EOF is not reached; however, f.next() uses a
152 readahead buffer that messes up the file position, so mixing
153 f.next() and f.readline() (or other methods) doesn't work right.
154 Calling f.seek() drops the readahead buffer, but other operations
155 don't. It so happens that this gives a nice additional speed boost
156 to "for line in file:"; the xreadlines method and corresponding
Guido van Rossumbffb2ef2002-08-09 17:17:07 +0000157 module are now obsolete. Thanks to Oren Tirosh!
Guido van Rossumb57089c2002-08-06 16:20:26 +0000158
Guido van Rossumde392d32002-08-05 14:17:20 +0000159- Encoding declarations (PEP 263, phase 1) have been implemented. A
160 comment of the form "# -*- coding: <encodingname> -*-" in the first
161 or second line of a Python source file indicates the encoding.
Martin v. Löwis00f1e3f2002-08-04 17:29:52 +0000162
Tim Petersf47630f2002-08-01 02:34:51 +0000163- list.sort() has a new implementation. While cross-platform results
164 may vary, and in data-dependent ways, this is much faster on many
165 kinds of partially ordered lists than the previous implementation,
166 and reported to be just as fast on randomly ordered lists on
167 several major platforms. This sort is also stable (if A==B and A
168 precedes B in the list at the start, A precedes B after the sort too),
169 although the language definition does not guarantee stability. A
170 potential drawback is that list.sort() may require temp space of
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000171 len(list)*2 bytes (\*4 on a 64-bit machine). It's therefore possible
Tim Petersf47630f2002-08-01 02:34:51 +0000172 for list.sort() to raise MemoryError now, even if a comparison function
173 does not. See <http://www.python.org/sf/587076> for full details.
174
Guido van Rossum2d5389c2002-07-23 03:44:35 +0000175- All standard iterators now ensure that, once StopIteration has been
176 raised, all future calls to next() on the same iterator will also
177 raise StopIteration. There used to be various counterexamples to
178 this behavior, which could caused confusion or subtle program
179 breakage, without any benefits. (Note that this is still an
180 iterator's responsibility; the iterator framework does not enforce
181 this.)
182
Mark Hammondc0e35152002-07-16 01:32:30 +0000183- Ctrl+C handling on Windows has been made more consistent with
184 other platforms. KeyboardInterrupt can now reliably be caught,
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000185 and Ctrl+C at an interactive prompt no longer terminates the
Mark Hammondc0e35152002-07-16 01:32:30 +0000186 process under NT/2k/XP (it never did under Win9x). Ctrl+C will
Tim Peters5af4e6c2002-08-12 02:31:19 +0000187 interrupt time.sleep() in the main thread, and any child processes
188 created via the popen family (on win2k; we can't make win9x work
Mark Hammond8f3afc72002-08-10 06:26:31 +0000189 reliably) are also interrupted (as generally happens on for Linux/Unix.)
190 [SF bugs 231273, 439992 and 581232]
Mark Hammondc0e35152002-07-16 01:32:30 +0000191
Raymond Hettinger5a04aec2002-06-25 00:25:30 +0000192- Slices and repetitions of buffer objects now consistently return
193 a string. Formerly, strings would be returned most of the time,
194 but a buffer object would be returned when the repetition count
195 was one or when the slice range was all inclusive.
196
Walter Dörwald3430d702002-06-17 10:43:59 +0000197- Unicode objects in sys.path are no longer ignored but treated
198 as directory names.
199
Neal Norwitz1f68fc72002-06-14 00:50:42 +0000200- Fixed string.startswith and string.endswith builtin methods
201 so they accept negative indices. [SF bug 493951]
202
Guido van Rossumc5fe5eb2002-06-12 03:45:21 +0000203- Fixed a bug with a continue inside a try block and a yield in the
204 finally clause. [SF bug 567538]
205
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000206- Most builtin sequences now support "extended slices", i.e. slices
Guido van Rossum2e82e712002-06-13 11:41:07 +0000207 with a third "stride" parameter. For example, "hello world"[::-1]
208 gives "dlrow olleh".
Michael W. Hudson5efaf7e2002-06-11 10:55:12 +0000209
Neal Norwitzd68f5172002-05-29 15:54:55 +0000210- A new warning PendingDeprecationWarning was added to provide
211 direction on features which are in the process of being deprecated.
212 The warning will not be printed by default. To see the pending
213 deprecations, use -Walways::PendingDeprecationWarning::
214 as a command line option or warnings.filterwarnings() in code.
215
Fred Draked0ba6362002-05-02 21:28:26 +0000216- Deprecated features of xrange objects have been removed as
217 promised. The start, stop, and step attributes and the tolist()
218 method no longer exist. xrange repetition and slicing have been
219 removed.
220
Guido van Rossum7dab2422002-04-26 19:40:56 +0000221- New builtin function enumerate(x), from PEP 279. Example:
222 enumerate("abc") is an iterator returning (0,"a"), (1,"b"), (2,"c").
223 The argument can be an arbitrary iterable object.
224
Neil Schemenauer89e3ee02002-04-26 01:58:53 +0000225- The assert statement no longer tests __debug__ at runtime. This means
226 that assert statements cannot be disabled by assigning a false value
227 to __debug__.
228
Walter Dörwald068325e2002-04-15 13:36:47 +0000229- A method zfill() was added to str and unicode, that fills a numeric
230 string to the left with zeros. For example,
231 "+123".zfill(6) -> "+00123".
232
Guido van Rossum862fe3c2002-04-15 12:36:47 +0000233- Complex numbers supported divmod() and the // and % operators, but
234 these make no sense. Since this was documented, they're being
235 deprecated now.
236
Guido van Rossum26dd8302002-04-26 20:11:29 +0000237- String and unicode methods lstrip(), rstrip() and strip() now take
238 an optional argument that specifies the characters to strip. For
239 example, "Foo!!!?!?!?".rstrip("?!") -> "Foo".
Guido van Rossum49042042002-04-13 00:59:05 +0000240
Guido van Rossumc69343b2002-04-12 19:22:48 +0000241- Added a new dict method pop(key). This removes and returns the
242 value corresponding to key. [SF patch #539949]
243
Guido van Rossum47834462002-04-04 15:21:33 +0000244- A new built-in type, bool, has been added, as well as built-in
245 names for its two values, True and False. Comparisons and sundry
246 other operations that return a truth value have been changed to
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000247 return a bool instead. Read PEP 285 for an explanation of why this
Guido van Rossum47834462002-04-04 15:21:33 +0000248 is backward compatible.
249
Guido van Rossum95b62a62002-03-29 01:07:24 +0000250- Fixed two bugs reported as SF #535905: under certain conditions,
251 deallocating a deeply nested structure could cause a segfault in the
252 garbage collector, due to interaction with the "trashcan" code;
253 access to the current frame during destruction of a local variable
254 could access a pointer to freed memory.
255
Guido van Rossumfe0ca4a2002-06-18 21:20:13 +0000256- The optional object allocator ("pymalloc") has been enabled by
257 default. The recommended practice for memory allocation and
258 deallocation has been streamlined. A header file is included,
259 Misc/pymemcompat.h, which can be bundled with 3rd party extensions
260 and lets them use the same API with Python versions from 1.5.2
261 onwards.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000262
Martin v. Löwiscfeb3b62002-03-03 21:30:27 +0000263- PyErr_Display will provide file and line information for all exceptions
264 that have an attribute print_file_and_line, not just SyntaxErrors.
265
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000266- The UTF-8 codec will now encode and decode Unicode surrogates
267 correctly and without raising exceptions for unpaired ones.
268
Guido van Rossumadd88062002-08-15 14:01:14 +0000269- Universal newlines (PEP 278) is implemented. Briefly, using 'U'
270 instead of 'r' when opening a text file for reading changes the line
271 ending convention so that any of '\r', '\r\n', and '\n' is
272 recognized (even mixed in one file); all three are converted to
273 '\n', the standard Python line end character.
274
Neal Norwitz649b7592002-01-01 19:07:13 +0000275- file.xreadlines() now raises a ValueError if the file is closed:
276 Previously, an xreadlines object was returned which would raise
277 a ValueError when the xreadlines.next() method was called.
278
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000279- sys.exit() inadvertently allowed more than one argument.
Neal Norwitz0c766a02002-03-27 13:03:09 +0000280 An exception will now be raised if more than one argument is used.
281
Tim Petersaf8446f2001-12-21 21:36:50 +0000282Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000283-----------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000284
Martin v. Löwis658009a2002-09-16 17:26:24 +0000285- cPickle.BadPickleGet is now a class.
286
Martin v. Löwisa32c9942002-09-09 16:17:47 +0000287- The time stamps in os.stat_result are floating point numbers now.
Martin v. Löwis94717ed2002-09-09 14:24:16 +0000288
Neal Norwitzb5673922002-09-05 21:48:07 +0000289- If the size passed to mmap.mmap() is larger than the length of the
290 file on non-Windows platforms, a ValueError is raised. [SF bug 585792]
291
Guido van Rossumb57089c2002-08-06 16:20:26 +0000292- The xreadlines module is slated for obsolescence.
293
Guido van Rossum79f0a102002-07-23 03:32:08 +0000294- The strptime function in the time module is now always available (a
295 Python implementation is used when the C library doesn't define it).
296
Guido van Rossum9562bcf2002-06-14 21:31:18 +0000297- The 'new' module is no longer an extension, but a Python module that
298 only exists for backwards compatibility. Its contents are no longer
299 functions but callable type objects.
300
Tim Peters81b92512002-04-29 01:37:32 +0000301- The bsddb.*open functions can now take 'None' as a filename.
Anthony Baxter83888952002-04-23 02:11:05 +0000302 This will create a temporary in-memory bsddb that won't be
Tim Peters81b92512002-04-29 01:37:32 +0000303 written to disk.
Anthony Baxter83888952002-04-23 02:11:05 +0000304
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +0000305- posix.lchown, posix.killpg, posix.mknod, and posix.getpgid have been
306 added where available.
Martin v. Löwis06a83e92002-04-14 10:19:44 +0000307
Martin v. Löwis2e64c342002-03-27 18:49:02 +0000308- The locale module now exposes the C library's gettext interface.
309
Tim Petersfbf74f22002-03-14 19:06:01 +0000310- A security hole ("double free") was found in zlib-1.1.3, a popular
311 third party compression library used by some Python modules. The
312 hole was quickly plugged in zlib-1.1.4, and the Windows build of
313 Python now ships with zlib-1.1.4.
314
Martin v. Löwis688357e2002-04-08 21:28:20 +0000315- pwd, grp, and resource return enhanced tuples now, with symbolic
316 field names.
Martin v. Löwis29001ff2002-03-01 10:47:37 +0000317
Martin v. Löwis99866332002-03-01 10:27:01 +0000318- array.array is now a type object. A new format character
319 'u' indicates Py_UNICODE arrays. For those, .tounicode and
320 .fromunicode methods are available. Arrays now support __iadd__
321 and __imul__.
322
Neal Norwitze790eae2002-01-01 21:14:12 +0000323- dl now builds on every system that has dlfcn.h. Failure in case
Martin v. Löwis93227272002-01-01 20:18:30 +0000324 of sizeof(int)!=sizeof(long)!=sizeof(void*) is delayed until dl.open
325 is called.
326
Michael W. Hudson34f20ea2002-05-27 15:08:24 +0000327- signal.sigpending, signal.sigprocmask and signal.sigsuspend have
328 been added where available.
329
Skip Montanaro8e790e72002-09-03 13:25:17 +0000330- The sys module acquired a new attribute, api_version, which evaluates
331 to the value of the PYTHON_API_VERSION macro with which the
332 interpreter was compiled.
333
Tim Petersaf8446f2001-12-21 21:36:50 +0000334Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000335-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000336
Walter Dörwald5ccaf8f2002-09-06 16:15:58 +0000337- mimetypes has two new functions: guess_all_extensions() which
338 returns a list of all known extensions for a mime type, and
339 add_type() which adds one mapping between a mime type and
340 an extension to the database.
341
Guido van Rossumd8ab35c2002-08-19 16:25:46 +0000342- New module: sets, defines the class Set that implements a mutable
343 set type using the keys of a dict to represent the set. There's
344 also a class ImmutableSet which is useful when you need sets of sets
345 or when you need to use sets as dict keys, and a class BaseSet which
346 is the base class of the two. (This is not documented yet, but
347 help(sets) gives a wealth of information.)
348
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +0000349- Added operator.pow(a,b) which is equivalent to a**b.
350
Tim Peters012c0a32002-08-16 03:40:07 +0000351- random.randrange(-sys.maxint-1, sys.maxint) no longer raises
352 OverflowError. That is, it now accepts any combination of 'start'
353 and 'stop' arguments so long as each is in the range of Python's
354 bounded integers.
355
Guido van Rossum4a57c332002-08-02 18:05:20 +0000356- New "algorithms" module: heapq, implements a heap queue. Thanks to
357 Kevin O'Connor for the code and François Pinard for an entertaining
358 write-up explaining the theory and practical uses of heaps.
359
Marc-André Lemburg58e2ff22002-07-12 14:40:04 +0000360- New encoding for the Palm OS character set: palmos.
361
Tim Peters943382c2002-07-07 03:59:34 +0000362- binascii.crc32() and the zipfile module had problems on some 64-bit
363 platforms. These have been fixed. On a platform with 8-byte C longs,
364 crc32() now returns a signed-extended 4-byte result, so that its value
365 as a Python int is equal to the value computed a 32-bit platform.
366
Martin v. Löwis7d650ca2002-06-30 15:05:00 +0000367- xml.dom.minidom.toxml and toprettyxml now take an optional encoding
368 argument.
369
Guido van Rossum9f7549b2002-06-10 21:39:42 +0000370- Some fixes in the copy module: when an object is copied through its
371 __reduce__ method, there was no check for a __setstate__ method on
372 the result [SF patch 565085]; deepcopy should treat instances of
373 custom metaclasses the same way it treats instances of type 'type'
374 [SF patch 560794].
375
Guido van Rossum5033c8e2002-06-07 12:40:52 +0000376- Sockets now support timeout mode. After s.settimeout(T), where T is
377 a float expressing seconds, subsequent operations raise an exception
378 if they cannot be completed within T seconds. To disable timeout
Guido van Rossum79f0a102002-07-23 03:32:08 +0000379 mode, use s.settimeout(None). There's also a module function,
380 socket.setdefaulttimeout(T), which sets the default for all sockets
381 created henceforth.
Guido van Rossum5033c8e2002-06-07 12:40:52 +0000382
383- getopt.gnu_getopt was added. This supports GNU-style option
384 processing, where options can be mixed with non-option arguments.
Martin v. Löwis446a25f2002-06-06 10:58:36 +0000385
Michael W. Hudsonb0dc1a32002-06-04 18:27:35 +0000386- Stop using strings for exceptions. String objects used for
387 exceptions are now classes deriving from Exception. The objects
388 changed were: Tkinter.TclError, bdb.BdbQuit, macpath.norm_error,
389 tabnanny.NannyNag, and xdrlib.Error.
Neal Norwitzb5b5a262002-06-04 17:14:07 +0000390
Walter Dörwald474458d2002-06-04 15:16:29 +0000391- Constants BOM_UTF8, BOM_UTF16, BOM_UTF16_LE, BOM_UTF16_BE,
392 BOM_UTF32, BOM_UTF32_LE and BOM_UTF32_BE that represent the Byte
393 Order Mark in UTF-8, UTF-16 and UTF-32 encodings for little and
394 big endian systems were added to the codecs module. The old names
395 BOM32_* and BOM64_* were off by a factor of 2.
396
Guido van Rossumf9257822002-06-18 20:43:18 +0000397- Added conversion functions math.degrees() and math.radians().
Raymond Hettinger87f59ee2002-05-13 04:17:32 +0000398
Raymond Hettinger9b1df1d2002-05-12 06:07:21 +0000399- ftplib.retrlines() now tests for callback is None rather than testing
400 for False. Was causing an error when given a callback object which
401 was callable but also returned len() as zero. The change may
402 create new breakage if the caller relied on the undocumented behavior
403 and called with callback set to [] or some other False value not
404 identical to None.
405
Tim Peters46c04e12002-05-05 20:40:00 +0000406- random.gauss() uses a piece of hidden state used by nothing else,
407 and the .seed() and .whseed() methods failed to reset it. In other
408 words, setting the seed didn't completely determine the sequence of
409 results produced by random.gauss(). It does now. Programs repeatedly
410 mixing calls to a seed method with calls to gauss() may see different
411 results now.
412
Fred Drake7f781c92002-05-01 20:33:53 +0000413- The pickle.Pickler class grew a clear_memo() method to mimic that
414 provided by cPickle.Pickler.
415
Tim Peters81b92512002-04-29 01:37:32 +0000416- difflib's SequenceMatcher class now does a dynamic analysis of
417 which elements are so frequent as to constitute noise. For
418 comparing files as sequences of lines, this generally works better
419 than the IS_LINE_JUNK function, and function ndiff's linejunk
420 argument defaults to None now as a result. A happy benefit is
421 that SequenceMatcher may run much faster now when applied
422 to large files with many duplicate lines (for example, C program
423 text with lots of repeated "}" and "return NULL;" lines).
424
Guido van Rossum256705b2002-04-23 13:29:43 +0000425- New Text.dump() method in Tkinter module.
426
Marc-André Lemburg1ec71ea2002-04-17 20:33:40 +0000427- New distutils commands for building packagers were added to
428 support pkgtool on Solaris and swinstall on HP-UX.
429
430- distutils now has a new abstract binary packager base class
431 command/bdist_packager, which simplifies writing packagers.
432 This will hopefully provide the missing bits to encourage
433 people to submit more packagers, e.g. for Debian, FreeBSD
434 and other systems.
435
Guido van Rossumf9257822002-06-18 20:43:18 +0000436- The UTF-16, -LE and -BE stream readers now raise a
437 NotImplementedError for all calls to .readline(). Previously, they
438 used to just produce garbage or fail with an encoding error --
439 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 +0000440 work well with these.
441
Martin v. Löwis5c137c22002-03-18 12:44:08 +0000442- compileall now supports quiet operation.
443
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000444- The BaseHTTPServer now implements optional HTTP/1.1 persistent
Martin v. Löwis587c98c2002-03-17 18:37:22 +0000445 connections.
446
Marc-André Lemburga5d2b4c2002-02-16 18:23:30 +0000447- socket module: the SSL support was broken out of the main
448 _socket module C helper and placed into a new _ssl helper
449 which now gets imported by socket.py if available and working.
450
Marc-André Lemburg37aa5802002-02-10 21:42:47 +0000451- encodings package: added aliases for all supported IANA character
452 sets
453
Guido van Rossum606fe4e2001-12-28 20:57:14 +0000454- ftplib: to safeguard the user's privacy, anonymous login will use
455 "anonymous@" as default password, rather than the real user and host
456 name.
457
Fred Drake36736122002-01-10 13:50:31 +0000458- webbrowser: tightened up the command passed to os.system() so that
459 arbitrary shell code can't be executed because a bogus URL was
460 passed in.
461
Tim Peters11bd9942002-02-01 00:52:29 +0000462- gettext.translation has an optional fallback argument, and
Martin v. Löwisa55ffae2002-01-11 06:58:49 +0000463 gettext.find an optional all argument. Translations will now fallback
464 on a per-message basis.
Martin v. Löwis1be64192002-01-11 06:33:28 +0000465
Martin v. Löwis9668b932002-01-12 11:27:42 +0000466- distutils bdist commands now offer a --skip-build option.
467
Walter Dörwaldb25c2b02002-03-21 10:38:40 +0000468- warnings.warn now accepts a Warning instance as first argument.
469
Fred Drakefed7e852002-04-04 19:36:15 +0000470- The xml.sax.expatreader.ExpatParser class will no longer create
471 circular references by using itself as the locator that gets passed
472 to the content handler implementation. [SF bug #535474]
473
Barry Warsaw47f3e2c2002-05-20 00:14:24 +0000474- The email.Parser.Parser class now properly parses strings regardless
475 of their line endings, which can be any of \r, \n, or \r\n (CR, LF,
476 or CRLF). Also, the Header class's constructor default arguments
477 has changed slightly so that an explicit maxlinelen value is always
478 honored.
479
Tim Petersaf8446f2001-12-21 21:36:50 +0000480Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000481-----------
Tim Petersaf8446f2001-12-21 21:36:50 +0000482
Guido van Rossum923e4ef2002-09-17 20:58:59 +0000483- The SGI demos (Demo/sgi) have been removed. Nobody thought they
484 were interesting any more. (The SGI library modules and extensions
485 are still there; it is believed that at least some of these are
486 still used and useful.)
487
Fred Drake40813b12002-08-05 15:24:19 +0000488- IDLE supports the new encoding declarations (PEP 263); it can also
489 deal with legacy 8-bit files if they use the locale's encoding. It
490 allows non-ASCII strings in the interactive shell and executes them
491 in the locale's encoding.
Martin v. Löwis98ce7b72002-08-05 15:11:26 +0000492
Marc-André Lemburg46260092002-04-04 16:17:11 +0000493- freeze.py now produces binaries which can import shared modules,
494 unlike before when this failed due to missing symbol exports in
495 the generated binary.
496
Tim Petersaf8446f2001-12-21 21:36:50 +0000497Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000498-----
Tim Petersaf8446f2001-12-21 21:36:50 +0000499
Tim Petersf47630f2002-08-01 02:34:51 +0000500- The public Python C API will generally be declared using PyAPI_FUNC
Neal Norwitz1389f3e2002-07-22 13:21:10 +0000501 and PyAPI_DATA macros, while Python extension module init functions
502 will be declared with PyMODINIT_FUNC. DL_EXPORT/DL_IMPORT macros
503 are deprecated.
504
Tim Petersc6a3ff62002-07-08 22:11:52 +0000505- A bug was fixed that could cause COUNT_ALLOCS builds to segfault, or
506 get into infinite loops, when a new-style class got garbage-collected.
507 Unfortunately, to avoid this, the way COUNT_ALLOCS works requires
508 that new-style classes be immortal in COUNT_ALLOCS builds. Note that
509 COUNT_ALLOCS is not enabled by default, in either release or debug
510 builds, and that new-style classes are immortal only in COUNT_ALLOCS
511 builds.
512
Tim Peters943382c2002-07-07 03:59:34 +0000513- Compiling out the cyclic garbage collector is no longer an option.
514 The old symbol WITH_CYCLE_GC is now ignored, and Python.h arranges
515 that it's always defined (for the benefit of any extension modules
516 that may be conditionalizing on it). A bonus is that any extension
517 type participating in cyclic gc can choose to participate in the
518 Py_TRASHCAN mechanism now too; in the absence of cyclic gc, this used
519 to require editing the core to teach the trashcan mechanism about the
520 new type.
521
Martin v. Löwis0cec0ff2002-07-28 16:33:45 +0000522- According to Annex F of the current C standard,
Tim Peters1de41bf2002-07-03 03:31:20 +0000523
524 The Standard C macro HUGE_VAL and its float and long double analogs,
525 HUGE_VALF and HUGE_VALL, expand to expressions whose values are
526 positive infinities.
527
528 Python only uses the double HUGE_VAL, and only to #define its own symbol
529 Py_HUGE_VAL. Some platforms have incorrect definitions for HUGE_VAL.
530 pyport.h used to try to worm around that, but the workarounds triggered
531 other bugs on other platforms, so we gave up. If your platform defines
532 HUGE_VAL incorrectly, you'll need to #define Py_HUGE_VAL to something
533 that works on your platform. The only instance of this I'm sure about
534 is on an unknown subset of Cray systems, described here:
535
536 http://www.cray.com/swpubs/manuals/SN-2194_2.0/html-SN-2194_2.0/x3138.htm
537
538 Presumably 2.3a1 breaks such systems. If anyone uses such a system, help!
539
Martin v. Löwisa3fb4f72002-06-09 13:33:54 +0000540- The configure option --without-doc-strings can be used to remove the
541 doc strings from the builtin functions and modules; this reduces the
542 size of the executable.
543
Guido van Rossumadd88062002-08-15 14:01:14 +0000544- The universal newlines option (PEP 278) is on by default. On Unix
545 it can be disabled by passing --without-universal-newlines to the
546 configure script. On other platforms, remove
547 WITH_UNIVERSAL_NEWLINES from pyconfig.h.
Tim Peters639295f2002-04-21 07:30:30 +0000548
Martin v. Löwis1142de32002-03-29 16:28:31 +0000549- On Unix, a shared libpython2.3.so can be created with --enable-shared.
550
Tim Peters8deda702002-03-30 10:06:07 +0000551- All uses of the CACHE_HASH, INTERN_STRINGS, and DONT_SHARE_SHORT_STRINGS
552 preprocessor symbols were eliminated. The internal decisions they
553 controlled stopped being experimental long ago.
Tim Peters1f7df352002-03-29 03:29:08 +0000554
Fred Drake7d28b732002-05-02 21:17:00 +0000555- The tools used to build the documentation now work under Cygwin as
556 well as Unix.
557
Skip Montanaro57454e52002-06-14 20:30:31 +0000558- The bsddb and dbm module builds have been changed to try and avoid version
559 skew problems and disable linkage with Berkeley DB 1.85 unless the
560 installer knows what s/he's doing. See the section on building these
561 modules in the README file for details.
562
Tim Petersaf8446f2001-12-21 21:36:50 +0000563C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000564-----
Tim Petersaf8446f2001-12-21 21:36:50 +0000565
Guido van Rossum45ec02a2002-08-19 21:43:18 +0000566- The string object's layout has changed: the pointer member
567 ob_sinterned has been replaced by an int member ob_sstate. On some
568 platforms (e.g. most 64-bit systems) this may change the offset of
569 the ob_sval member, so as a precaution the API_VERSION has been
570 incremented. The apparently unused feature of "indirect interned
571 strings", supported by the ob_sinterned member, is gone. Interned
572 strings are now usually mortal; theres a new API,
573 PyString_InternImmortal() that creates immortal interned strings.
574 (The ob_sstate member can only take three values; however, while
575 making it a char saves a few bytes per string object on average, in
576 it also slowed things down a bit because ob_sval was no longer
577 aligned.)
578
Guido van Rossumfdb86482002-08-14 21:20:32 +0000579- The Py_InitModule*() functions now accept NULL for the 'methods'
580 argument. Modules without global functions are becoming more common
581 now that factories can be types rather than functions.
582
Marc-André Lemburgcc8764c2002-08-11 12:23:04 +0000583- New C API PyUnicode_FromOrdinal() which exposes unichr() at C
584 level.
585
Thomas Heller085358a2002-07-29 14:27:41 +0000586- New functions PyErr_SetExcFromWindowsErr() and
587 PyErr_SetExcFromWindowsErrWithFilename(). Similar to
588 PyErr_SetFromWindowsErrWithFilename() and
589 PyErr_SetFromWindowsErr(), but they allow to specify
590 the exception type to raise. Available on Windows.
591
Tim Peters7c321a82002-07-09 02:57:01 +0000592- Py_FatalError() is now declared as taking a const char* argument. It
593 was previously declared without const. This should not affect working
594 code.
595
Martin v. Löwis01f94bd2002-05-08 08:44:21 +0000596- Added new macro PySequence_ITEM(o, i) that directly calls
597 sq_item without rechecking that o is a sequence and without
598 adjusting for negative indices.
599
Fred Draked0ba6362002-05-02 21:28:26 +0000600- PyRange_New() now raises ValueError if the fourth argument is not 1.
601 This is part of the removal of deprecated features of the xrange
602 object.
603
Guido van Rossum517c7d42002-04-26 02:49:14 +0000604- PyNumber_Coerce() and PyNumber_CoerceEx() now also invoke the type's
605 coercion if both arguments have the same type but this type has the
606 CHECKTYPES flag set. This is to better support proxies.
607
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000608- The type of tp_free has been changed from "void (*)(PyObject \*)" to
609 "void (*)(void \*)".
Neil Schemenauer9344b142002-04-12 23:00:08 +0000610
611- PyObject_Del, PyObject_GC_Del are now functions instead of macros.
612
Guido van Rossum0986d822002-04-08 01:38:42 +0000613- A type can now inherit its metatype from its base type. Previously,
614 when PyType_Ready() was called, if ob_type was found to be NULL, it
615 was always set to &PyType_Type; now it is set to base->ob_type,
616 where base is tp_base, defaulting to &PyObject_Type.
617
618- PyType_Ready() accidentally did not inherit tp_is_gc; now it does.
619
Neil Schemenauerc9abc1d2002-05-08 14:14:41 +0000620- The PyCore_* family of APIs have been removed.
Neil Schemenauer9d50d132002-03-22 17:06:59 +0000621
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000622- The "u#" parser marker will now pass through Unicode objects as-is
Marc-André Lemburg3e3eacb2002-01-09 16:21:27 +0000623 without going through the buffer API.
624
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000625- The enumerators of cmp_op have been renamed to use the prefix ``PyCmp_``.
Martin v. Löwis7198a522002-01-01 19:59:11 +0000626
Tim Peters10a3bb52001-12-25 19:07:38 +0000627- An old #define of ANY as void has been removed from pyport.h. This
628 hasn't been used since Python's pre-ANSI days, and the #define has
629 been marked as obsolete since then. SF bug 495548 says it created
630 conflicts with other packages, so keeping it around wasn't harmless.
631
Tim Petersaf8446f2001-12-21 21:36:50 +0000632- Because Python's magic number scheme broke on January 1st, we decided
633 to stop Python development. Thanks for all the fish!
634
Tim Petersfb05db22002-03-11 00:24:00 +0000635- Some of us don't like fish, so we changed Python's magic number
Marc-André Lemburge92e0a92002-02-09 11:28:43 +0000636 scheme to a new one. See Python/import.c for details.
637
Tim Petersaf8446f2001-12-21 21:36:50 +0000638New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000639-------------
Tim Petersaf8446f2001-12-21 21:36:50 +0000640
Martin v. Löwisf90ae202002-06-11 06:22:31 +0000641- AtheOS is now supported.
642
Andrew MacIntyre161ad0e2002-08-04 07:25:58 +0000643- the EMX runtime environment on OS/2 is now supported.
644
Martin v. Löwisa6e97582002-01-01 18:41:33 +0000645- GNU/Hurd is now supported.
646
Tim Petersaf8446f2001-12-21 21:36:50 +0000647Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000648-----
649
650Yet to be written.
Tim Petersaf8446f2001-12-21 21:36:50 +0000651
652Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000653-------
Tim Petersaf8446f2001-12-21 21:36:50 +0000654
Tim Peters08e72952002-04-16 20:48:01 +0000655- Sometimes the uninstall executable (UNWISE.EXE) vanishes. One cause
656 of that has been fixed in the installer (disabled Wise's "delete in-
657 use files" uninstall option).
658
Guido van Rossum181e41a2002-04-06 00:23:25 +0000659- Fixed a bug in urllib's proxy handling in Windows. [SF bug #503031]
660
Tim Peters33187922002-04-04 20:02:04 +0000661- The installer now installs Start menu shortcuts under (the local
662 equivalent of) "All Users" when doing an Admin install.
663
Tim Petersfb05db22002-03-11 00:24:00 +0000664- file.truncate([newsize]) now works on Windows for all newsize values.
665 It used to fail if newsize didn't fit in 32 bits, reflecting a
666 limitation of MS _chsize (which is no longer used).
667
Tim Petersab034fa2002-02-01 11:27:43 +0000668- os.waitpid() is now implemented for Windows, and can be used to block
669 until a specified process exits. This is similar to, but not exactly
670 the same as, os.waitpid() on POSIX systems. If you're waiting for
671 a specific process whose pid was obtained from one of the spawn()
672 functions, the same Python os.waitpid() code works across platforms.
Tim Peters33187922002-04-04 20:02:04 +0000673 See the docs for details. The docs were changed to clarify that
674 spawn functions return, and waitpid requires, a process handle on
675 Windows (not the same thing as a Windows process id).
Tim Petersab034fa2002-02-01 11:27:43 +0000676
Tim Peters11bd9942002-02-01 00:52:29 +0000677- New tempfile.TemporaryFile implementation for Windows: this doesn't
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000678 need a TemporaryFileWrapper wrapper anymore, and should be immune
Tim Peters11bd9942002-02-01 00:52:29 +0000679 to a nasty problem: before 2.3, if you got a temp file on Windows, it
680 got wrapped in an object whose close() method first closed the
681 underlying file, then deleted the file. This usually worked fine.
682 However, the spawn family of functions on Windows create (at a low C
683 level) the same set of open files in the spawned process Q as were
684 open in the spawning process P. If a temp file f was among them, then
685 doing f.close() in P first closed P's C-level file handle on f, but Q's
686 C-level file handle on f remained open, so the attempt in P to delete f
687 blew up with a "Permission denied" error (Windows doesn't allow
688 deleting open files). This was surprising, subtle, and difficult to
689 work around.
690
691- The os module now exports all the symbolic constants usable with the
692 low-level os.open() on Windows: the new constants in 2.3 are
693 O_NOINHERIT, O_SHORT_LIVED, O_TEMPORARY, O_RANDOM and O_SEQUENTIAL.
694 The others were also available in 2.2: O_APPEND, O_BINARY, O_CREAT,
695 O_EXCL, O_RDONLY, O_RDWR, O_TEXT, O_TRUNC and O_WRONLY. Contrary
696 to Microsoft docs, O_SHORT_LIVED does not seem to imply O_TEMPORARY
697 (so specify both if you want both; note that neither is useful unless
698 specified with O_CREAT too).
699
Tim Petersaf8446f2001-12-21 21:36:50 +0000700Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000701----
702
703Yet to be written.
Tim Petersaf8446f2001-12-21 21:36:50 +0000704
705
Tim Peters909c0912001-12-14 23:16:18 +0000706What's New in Python 2.2 final?
Tim Peters909c0912001-12-14 23:16:18 +0000707===============================
708
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000709*Release date: 21-Dec-2001*
710
Tim Peters909c0912001-12-14 23:16:18 +0000711Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000712--------------------------------------------
Tim Peters909c0912001-12-14 23:16:18 +0000713
Barry Warsaw52acb492001-12-21 20:04:22 +0000714- pickle.py, cPickle: allow pickling instances of new-style classes
715 with a custom metaclass.
716
Tim Peters909c0912001-12-14 23:16:18 +0000717Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000718-----------------
Tim Peters909c0912001-12-14 23:16:18 +0000719
Barry Warsaw52acb492001-12-21 20:04:22 +0000720- weakref proxy object: when comparing, unwrap both arguments if both
721 are proxies.
722
Tim Peters909c0912001-12-14 23:16:18 +0000723Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000724-----------------
Tim Peters909c0912001-12-14 23:16:18 +0000725
Barry Warsaw52acb492001-12-21 20:04:22 +0000726- binascii.b2a_base64(): fix a potential buffer overrun when encoding
727 very short strings.
728
729- cPickle: the obscure "fast" mode was suspected of causing stack
730 overflows on the Mac. Hopefully fixed this by setting the recursion
731 limit much smaller. If the limit is too low (it only affects
732 performance), you can change it by defining PY_CPICKLE_FAST_LIMIT
733 when compiling cPickle.c (or in pyconfig.h).
734
Tim Peters909c0912001-12-14 23:16:18 +0000735Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000736-------
Tim Peters909c0912001-12-14 23:16:18 +0000737
Barry Warsaw52acb492001-12-21 20:04:22 +0000738- dumbdbm.py: fixed a dumb old bug (the file didn't get synched at
739 close or delete time).
740
741- rfc822.py: fixed a bug where the address '<>' was converted to None
742 instead of an empty string (also fixes the email.Utils module).
743
744- xmlrpclib.py: version 1.0.0; uses precision for doubles.
745
746- test suite: the pickle and cPickle tests were not executing any code
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000747 when run from the standard regression test.
Barry Warsaw52acb492001-12-21 20:04:22 +0000748
Tim Peters909c0912001-12-14 23:16:18 +0000749Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000750-----------
Tim Peters909c0912001-12-14 23:16:18 +0000751
752Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000753-----
Tim Peters909c0912001-12-14 23:16:18 +0000754
755C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000756-----
Tim Peters909c0912001-12-14 23:16:18 +0000757
758New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000759-------------
Tim Peters909c0912001-12-14 23:16:18 +0000760
761Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000762-----
Tim Peters909c0912001-12-14 23:16:18 +0000763
764Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000765-------
Tim Peters909c0912001-12-14 23:16:18 +0000766
Barry Warsaw52acb492001-12-21 20:04:22 +0000767- distutils package: fixed broken Windows installers (bdist_wininst).
768
769- tempfile.py: prevent mysterious warnings when TemporaryFileWrapper
770 instances are deleted at process exit time.
771
772- socket.py: prevent mysterious warnings when socket instances are
773 deleted at process exit time.
774
775- posixmodule.c: fix a Windows crash with stat() of a filename ending
776 in backslash.
777
Tim Peters909c0912001-12-14 23:16:18 +0000778Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000779----
Tim Peters909c0912001-12-14 23:16:18 +0000780
Barry Warsaw52acb492001-12-21 20:04:22 +0000781- The Carbon toolbox modules have been upgraded to Universal Headers
782 3.4, and experimental CoreGraphics and CarbonEvents modules have
783 been added. All only for framework-enabled MacOSX.
784
Tim Peters909c0912001-12-14 23:16:18 +0000785
Tim Peters6272dfd2001-12-13 19:34:00 +0000786What's New in Python 2.2c1?
Tim Petersb3c9af12001-11-17 00:21:57 +0000787===========================
788
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000789*Release date: 14-Dec-2001*
790
Tim Petersb3c9af12001-11-17 00:21:57 +0000791Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000792--------------------------------------------
Tim Petersb3c9af12001-11-17 00:21:57 +0000793
Barry Warsaw06557452001-12-14 20:47:12 +0000794- Guido's tutorial introduction to the new type/class features has
795 been extensively updated. See
796
797 http://www.python.org/2.2/descrintro.html
798
799 That remains the primary documentation in this area.
800
Guido van Rossum33bab012001-12-05 22:45:48 +0000801- Fixed a leak: instance variables declared with __slots__ were never
802 deleted!
803
Guido van Rossum4b800852001-12-03 00:54:52 +0000804- The "delete attribute" method of descriptor objects is called
805 __delete__, not __del__. In previous releases, it was mistakenly
806 called __del__, which created an unfortunate overloading condition
807 with finalizers. (The "get attribute" and "set attribute" methods
808 are still called __get__ and __set__, respectively.)
809
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +0000810- Some subtle issues with the super built-in were fixed:
811
812 (a) When super itself is subclassed, its __get__ method would still
813 return an instance of the base class (i.e., of super).
814
815 (b) super(C, C()).__class__ would return C rather than super. This
816 is confusing. To fix this, I decided to change the semantics of
817 super so that it only applies to code attributes, not to data
818 attributes. After all, overriding data attributes is not
819 supported anyway.
820
821 (c) The __get__ method didn't check whether the argument was an
822 instance of the type used in creation of the super instance.
823
Guido van Rossumcd7b7d62001-12-04 21:02:07 +0000824- Previously, hash() of an instance of a subclass of a mutable type
825 (list or dictionary) would return some value, rather than raising
826 TypeError. This has been fixed. Also, directly calling
827 dict.__hash__ and list.__hash__ now raises the same TypeError
828 (previously, these were the same as object.__hash__).
Guido van Rossumcdbbd0a2001-12-03 15:46:59 +0000829
Guido van Rossumd331cb52001-12-05 19:46:42 +0000830- New-style objects now support deleting their __dict__. This is for
831 all intents and purposes equivalent to assigning a brand new empty
832 dictionary, but saves space if the object is not used further.
833
Tim Petersb3c9af12001-11-17 00:21:57 +0000834Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000835-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +0000836
Tim Peters3caca232001-12-06 06:23:26 +0000837- -Qnew now works as documented in PEP 238: when -Qnew is passed on
838 the command line, all occurrences of "/" use true division instead
839 of classic division. See the PEP for details. Note that "all"
840 means all instances in library and 3rd-party modules, as well as in
841 your own code. As the PEP says, -Qnew is intended for use only in
842 educational environments with control over the libraries in use.
Tim Petersbf72fe22001-12-11 21:43:14 +0000843 Note that test_coercion.py in the standard Python test suite fails
844 under -Qnew; this is expected, and won't be repaired until true
845 division becomes the default (in the meantime, test_coercion is
846 testing the current rules).
Tim Peters3caca232001-12-06 06:23:26 +0000847
Fred Drake6c01e252001-12-14 17:08:12 +0000848- complex() now only allows the first argument to be a string
849 argument, and raises TypeError if either the second arg is a string
850 or if the second arg is specified when the first is a string.
851
Tim Petersb3c9af12001-11-17 00:21:57 +0000852Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000853-----------------
Tim Petersb3c9af12001-11-17 00:21:57 +0000854
Martin v. Löwis560da622001-11-24 09:24:51 +0000855- gc.get_referents was renamed to gc.get_referrers.
856
Tim Petersb3c9af12001-11-17 00:21:57 +0000857Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000858-------
Tim Petersb3c9af12001-11-17 00:21:57 +0000859
Tim Peters25059d32001-12-07 20:35:43 +0000860- Functions in the os.spawn() family now release the global interpreter
861 lock around calling the platform spawn. They should always have done
862 this, but did not before 2.2c1. Multithreaded programs calling
863 an os.spawn function with P_WAIT will no longer block all Python threads
864 until the spawned program completes. It's possible that some programs
865 relies on blocking, although more likely by accident than by design.
866
Martin v. Löwis3a89b2b2001-11-25 14:35:58 +0000867- webbrowser defaults to netscape.exe on OS/2 now.
868
Martin v. Löwis652e1912001-11-25 14:50:56 +0000869- Tix.ResizeHandle exposes detach_widget, hide, and show.
870
Martin v. Löwis714d2e22001-12-02 12:26:03 +0000871- The charset alias windows_1252 has been added.
872
Barry Warsaw06557452001-12-14 20:47:12 +0000873- types.StringTypes is a tuple containing the defined string types;
874 usually this will be (str, unicode), but if Python was compiled
875 without Unicode support it will be just (str,).
876
877- The pulldom and minidom modules were synchronized to PyXML.
878
Tim Petersb3c9af12001-11-17 00:21:57 +0000879Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000880-----------
Tim Petersb3c9af12001-11-17 00:21:57 +0000881
Barry Warsaw06557452001-12-14 20:47:12 +0000882- A new script called Tools/scripts/google.py was added, which fires
883 off a search on Google.
884
Tim Petersb3c9af12001-11-17 00:21:57 +0000885Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000886-----
Tim Petersb3c9af12001-11-17 00:21:57 +0000887
Barry Warsaw06557452001-12-14 20:47:12 +0000888- Note that release builds of Python should arrange to define the
889 preprocessor symbol NDEBUG on the command line (or equivalent).
890 In the 2.2 pre-release series we tried to define this by magic in
891 Python.h instead, but it proved to cause problems for extension
892 authors. The Unix, Windows and Mac builds now all define NDEBUG in
893 release builds via cmdline (or equivalent) instead. Ports to
894 other platforms should do likewise.
895
Jack Jansen1999ef42001-12-06 21:47:20 +0000896- It is no longer necessary to use --with-suffix when building on a
897 case-insensitive file system (such as Mac OS X HFS+). In the build
898 directory an extension is used, but not in the installed python.
899
Tim Petersb3c9af12001-11-17 00:21:57 +0000900C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000901-----
Tim Petersb3c9af12001-11-17 00:21:57 +0000902
Tim Petersf582b822001-12-11 18:51:08 +0000903- New function PyDict_MergeFromSeq2() exposes the builtin dict
904 constructor's logic for updating a dictionary from an iterable object
905 producing key-value pairs.
906
Tim Peterscffed4b2001-11-29 03:26:37 +0000907- PyArg_ParseTupleAndKeywords() requires that the number of entries in
Tim Petersf582b822001-12-11 18:51:08 +0000908 the keyword list equal the number of argument specifiers. This
Tim Peterscffed4b2001-11-29 03:26:37 +0000909 wasn't checked correctly, and PyArg_ParseTupleAndKeywords could even
910 dump core in some bad cases. This has been repaired. As a result,
911 PyArg_ParseTupleAndKeywords may raise RuntimeError in bad cases that
912 previously went unchallenged.
913
Tim Petersb3c9af12001-11-17 00:21:57 +0000914New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000915-------------
Tim Petersb3c9af12001-11-17 00:21:57 +0000916
917Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000918-----
Tim Petersb3c9af12001-11-17 00:21:57 +0000919
920Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000921-------
Tim Petersb3c9af12001-11-17 00:21:57 +0000922
923Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000924----
Tim Petersb3c9af12001-11-17 00:21:57 +0000925
Jack Jansenffa260f2001-12-06 21:14:00 +0000926- In unix-Python on Mac OS X (and darwin) sys.platform is now "darwin",
927 without any trailing digits.
Tim Petersb3c9af12001-11-17 00:21:57 +0000928
Barry Warsaw06557452001-12-14 20:47:12 +0000929- Changed logic for finding python home in Mac OS X framework Pythons.
930 Now sys.executable points to the executable again, in stead of to
931 the shared library. The latter is used only for locating the python
932 home.
933
934
Tim Peters84362bc2001-10-19 17:55:30 +0000935What's New in Python 2.2b2?
Tim Peters84362bc2001-10-19 17:55:30 +0000936===========================
937
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000938*Release date: 16-Nov-2001*
939
Tim Peters84362bc2001-10-19 17:55:30 +0000940Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000941--------------------------------------------
Tim Peters84362bc2001-10-19 17:55:30 +0000942
Guido van Rossum3d27df02001-11-15 20:27:54 +0000943- Multiple inheritance mixing new-style and classic classes in the
944 list of base classes is now allowed, so this works now:
Tim Peters76f7fe32001-11-15 20:02:21 +0000945
946 class Classic: pass
Guido van Rossum3d27df02001-11-15 20:27:54 +0000947 class Mixed(Classic, object): pass
Tim Peters76f7fe32001-11-15 20:02:21 +0000948
949 The MRO (method resolution order) for each base class is respected
950 according to its kind, but the MRO for the derived class is computed
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000951 using new-style MRO rules if any base class is a new-style class.
Tim Peters76f7fe32001-11-15 20:02:21 +0000952 This needs to be documented.
953
Tim Petersa427a2b2001-10-29 22:25:45 +0000954- The new builtin dictionary() constructor, and dictionary type, have
955 been renamed to dict. This reflects a decade of common usage.
956
Guido van Rossum3fc08d22001-11-15 20:33:10 +0000957- dict() now accepts an iterable object producing 2-sequences. For
958 example, dict(d.items()) == d for any dictionary d. The argument,
959 and the elements of the argument, can be any iterable objects.
960
Guido van Rossum7ad2d1e2001-10-29 22:11:00 +0000961- New-style classes can now have a __del__ method, which is called
962 when the instance is deleted (just like for classic classes).
963
Guido van Rossum12d955c2001-10-26 14:56:06 +0000964- Assignment to object.__dict__ is now possible, for objects that are
965 instances of new-style classes that have a __dict__ (unless the base
966 class forbids it).
967
Guido van Rossumc8e56452001-10-22 00:43:43 +0000968- Methods of built-in types now properly check for keyword arguments
969 (formerly these were silently ignored). The only built-in methods
970 that take keyword arguments are __call__, __init__ and __new__.
971
Guido van Rossum86443212001-10-27 22:28:54 +0000972- The socket function has been converted to a type; see below.
973
Tim Peters84362bc2001-10-19 17:55:30 +0000974Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000975-----------------
Tim Peters84362bc2001-10-19 17:55:30 +0000976
Jeremy Hylton249aaed2001-11-09 21:06:24 +0000977- Assignment to __debug__ raises SyntaxError at compile-time. This
978 was promised when 2.1c1 was released as "What's New in Python 2.1c1"
Barry Warsaw012852b2001-11-16 16:17:27 +0000979 (see below) says.
Jeremy Hylton249aaed2001-11-09 21:06:24 +0000980
Guido van Rossum12d955c2001-10-26 14:56:06 +0000981- Clarified the error messages for unsupported operands to an operator
982 (like 1 + '').
983
Tim Peters84362bc2001-10-19 17:55:30 +0000984Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +0000985-----------------
Tim Peters84362bc2001-10-19 17:55:30 +0000986
Tim Peters5ebfd362001-11-13 23:11:19 +0000987- mmap has a new keyword argument, "access", allowing a uniform way for
988 both Windows and Unix users to create read-only, write-through and
989 copy-on-write memory mappings. This was previously possible only on
990 Unix. A new keyword argument was required to support this in a
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +0000991 uniform way because the mmap() signatures had diverged across
Tim Peters5ebfd362001-11-13 23:11:19 +0000992 platforms. Thanks to Jay T Miller for repairing this!
993
Tim Peters169ded02001-11-03 19:57:21 +0000994- By default, the gc.garbage list now contains only those instances in
995 unreachable cycles that have __del__ methods; in 2.1 it contained all
996 instances in unreachable cycles. "Instances" here has been generalized
997 to include instances of both new-style and old-style classes.
998
Guido van Rossum12d955c2001-10-26 14:56:06 +0000999- The socket module defines a new method for socket objects,
1000 sendall(). This is like send() but may make multiple calls to
Guido van Rossum86443212001-10-27 22:28:54 +00001001 send() until all data has been sent. Also, the socket function has
1002 been converted to a subclassable type, like list and tuple (etc.)
1003 before it; socket and SocketType are now the same thing.
Guido van Rossum12d955c2001-10-26 14:56:06 +00001004
1005- Various bugfixes to the curses module. There is now a test suite
1006 for the curses module (you have to run it manually).
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001007
Guido van Rossum692adf12001-10-30 03:03:03 +00001008- binascii.b2a_base64 no longer places an arbitrary restriction of 57
1009 bytes on its input.
1010
Tim Peters84362bc2001-10-19 17:55:30 +00001011Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001012-------
Tim Peters84362bc2001-10-19 17:55:30 +00001013
Tim Peters5ebfd362001-11-13 23:11:19 +00001014- tkFileDialog exposes a Directory class and askdirectory
Martin v. Löwis25ee87c2001-11-07 22:38:08 +00001015 convenience function.
1016
Tim Peters75335872001-11-03 19:35:43 +00001017- Symbolic group names in regular expressions must be unique. For
1018 example, the regexp r'(?P<abc>)(?P<abc>)' is not allowed, because a
1019 single name can't mean both "group 1" and "group 2" simultaneously.
Barry Warsaw012852b2001-11-16 16:17:27 +00001020 Python 2.2 detects this error at regexp compilation time;
1021 previously, the error went undetected, and results were
1022 unpredictable. Also in sre, the pattern.split(), pattern.sub(), and
1023 pattern.subn() methods have been rewritten in C. Also, an
1024 experimental function/method finditer() has been added, which works
1025 like findall() but returns an iterator.
Tim Peters75335872001-11-03 19:35:43 +00001026
Martin v. Löwisb7b32602001-11-02 23:48:20 +00001027- Tix exposes more commands through the classes DirSelectBox,
1028 DirSelectDialog, ListNoteBook, Meter, CheckList, and the
1029 methods tix_addbitmapdir, tix_cget, tix_configure, tix_filedialog,
1030 tix_getbitmap, tix_getimage, tix_option_get, and tix_resetoptions.
1031
Tim Peters98791af2001-10-23 01:59:54 +00001032- Traceback objects are now scanned by cyclic garbage collection, so
1033 cycles created by casual use of sys.exc_info() no longer cause
1034 permanent memory leaks (provided garbage collection is enabled).
1035
Guido van Rossum49192142001-10-24 20:51:44 +00001036- os.extsep -- a new variable needed by the RISCOS support. It is the
1037 separator used by extensions, and is '.' on all platforms except
1038 RISCOS, where it is '/'. There is no need to use this variable
1039 unless you have a masochistic desire to port your code to RISCOS.
1040
Barry Warsaw012852b2001-11-16 16:17:27 +00001041- mimetypes.py has optional support for non-standard, but commonly
1042 found types. guess_type() and guess_extension() now accept an
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001043 optional 'strict' flag, defaulting to true, which controls whether
Barry Warsaw012852b2001-11-16 16:17:27 +00001044 recognize non-standard types or not. A few non-standard types we
1045 know about have been added. Also, when run as a script, there are
1046 new -l and -e options.
1047
1048- statcache is now deprecated.
1049
1050- email.Utils.formatdate() now produces the preferred RFC 2822 style
1051 dates with numeric timezones (it used to produce obsolete dates
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001052 hard coded to "GMT" timezone). An optional 'localtime' flag is
Barry Warsaw012852b2001-11-16 16:17:27 +00001053 added to produce dates in the local timezone, with daylight savings
1054 time properly taken into account.
1055
1056- In pickle and cPickle, instead of masking errors in load() by
1057 transforming them into SystemError, we let the original exception
1058 propagate out. Also, implement support for __safe_for_unpickling__
1059 in pickle, as it already was supported in cPickle.
1060
Tim Peters84362bc2001-10-19 17:55:30 +00001061Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001062-----------
Tim Peters84362bc2001-10-19 17:55:30 +00001063
1064Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001065-----
Tim Peters84362bc2001-10-19 17:55:30 +00001066
Barry Warsaw012852b2001-11-16 16:17:27 +00001067- The dbm module is built using libdb1 if available. The bsddb module
1068 is built with libdb3 if available.
1069
1070- Misc/Makefile.pre.in has been removed by BDFL pronouncement.
1071
Tim Peters84362bc2001-10-19 17:55:30 +00001072C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001073-----
Tim Peters84362bc2001-10-19 17:55:30 +00001074
Tim Peters1fc240e2001-10-26 05:06:50 +00001075- New function PySequence_Fast_GET_SIZE() returns the size of a non-
1076 NULL result from PySequence_Fast(), more quickly than calling
1077 PySequence_Size().
1078
Barry Warsaw012852b2001-11-16 16:17:27 +00001079- New argument unpacking function PyArg_UnpackTuple() added.
1080
1081- New functions PyObject_CallFunctionObjArgs() and
1082 PyObject_CallMethodObjArgs() have been added to make it more
1083 convenient and efficient to call functions and methods from C.
1084
1085- PyArg_ParseTupleAndKeywords() no longer masks errors, so it's
1086 possible that this will propagate errors it didn't before.
1087
1088- New function PyObject_CheckReadBuffer(), which returns true if its
1089 argument supports the single-segment readable buffer interface.
1090
Tim Peters84362bc2001-10-19 17:55:30 +00001091New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001092-------------
Tim Peters84362bc2001-10-19 17:55:30 +00001093
Guido van Rossum86443212001-10-27 22:28:54 +00001094- We've finally confirmed that this release builds on HP-UX 11.00,
1095 *with* threads, and passes the test suite.
1096
Tim Peters7a33d8b2001-11-05 02:51:07 +00001097- Thanks to a series of patches from Michael Muller, Python may build
1098 again under OS/2 Visual Age C++.
1099
Guido van Rossum49192142001-10-24 20:51:44 +00001100- Updated RISCOS port by Dietmar Schwertberger.
1101
Tim Peters84362bc2001-10-19 17:55:30 +00001102Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001103-----
Tim Peters84362bc2001-10-19 17:55:30 +00001104
Andrew M. Kuchling15e03532001-10-22 16:37:10 +00001105- Added a test script for the curses module. It isn't run automatically;
1106 regrtest.py must be run with '-u curses' to enable it.
1107
Tim Peters84362bc2001-10-19 17:55:30 +00001108Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001109-------
Tim Peters84362bc2001-10-19 17:55:30 +00001110
Barry Warsaw012852b2001-11-16 16:17:27 +00001111Mac
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001112----
Barry Warsaw012852b2001-11-16 16:17:27 +00001113
1114- PythonScript has been moved to unsupported and is slated to be
1115 removed completely in the next release.
1116
1117- It should now be possible to build applets that work on both OS9 and
1118 OSX.
1119
1120- The core is now linked with CoreServices not Carbon; as a side
1121 result, default 8bit encoding on OSX is now ASCII.
1122
1123- Python should now build on OSX 10.1.1
1124
Tim Peters84362bc2001-10-19 17:55:30 +00001125
Tim Petersabf925f2001-09-28 21:53:42 +00001126What's New in Python 2.2b1?
Tim Petersabf925f2001-09-28 21:53:42 +00001127===========================
1128
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001129*Release date: 19-Oct-2001*
1130
Tim Petersabf925f2001-09-28 21:53:42 +00001131Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001132--------------------------------------------
Tim Petersabf925f2001-09-28 21:53:42 +00001133
Guido van Rossum687ae002001-10-15 22:03:32 +00001134- New-style classes are now always dynamic (except for built-in and
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001135 extension types). There is no longer a performance penalty, and I
Guido van Rossum687ae002001-10-15 22:03:32 +00001136 no longer see another reason to keep this baggage around. One relic
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001137 remains: the __dict__ of a new-style class is a read-only proxy; you
1138 must set the class's attribute to modify it. As a consequence, the
Guido van Rossum687ae002001-10-15 22:03:32 +00001139 __defined__ attribute of new-style types no longer exists, for lack
1140 of need: there is once again only one __dict__ (although in the
Guido van Rossum3eea25c2001-10-16 00:46:57 +00001141 future a __cache__ may be resurrected with a similar function, if I
1142 can prove that it actually speeds things up).
Guido van Rossum50fda3b2001-10-04 19:46:06 +00001143
Tim Peters1c9ca872001-10-04 06:43:12 +00001144- C.__doc__ now works as expected for new-style classes (in 2.2a4 it
1145 always returned None, even when there was a class docstring).
1146
1147- doctest now finds and runs docstrings attached to new-style classes,
1148 class methods, static methods, and properties.
1149
Guido van Rossum9074ef62001-10-16 21:34:49 +00001150Core and builtins
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001151-----------------
Tim Petersabf925f2001-09-28 21:53:42 +00001152
Guido van Rossuma8bcf802001-10-15 15:53:58 +00001153- A very subtle syntactical pitfall in list comprehensions was fixed.
1154 For example: [a+b for a in 'abc', for b in 'def']. The comma in
1155 this example is a mistake. Previously, this would silently let 'a'
1156 iterate over the singleton tuple ('abc',), yielding ['abcd', 'abce',
1157 'abcf'] rather than the intended ['ad', 'ae', 'af', 'bd', 'be',
1158 'bf', 'cd', 'ce', 'cf']. Now, this is flagged as a syntax error.
1159 Note that [a for a in <singleton>] is a convoluted way to say
1160 [<singleton>] anyway, so it's not like any expressiveness is lost.
1161
Guido van Rossum9074ef62001-10-16 21:34:49 +00001162- getattr(obj, name, default) now only catches AttributeError, as
1163 documented, rather than returning the default value for all
1164 exceptions (which could mask bugs in a __getattr__ hook, for
1165 example).
1166
Fred Drakecb7a6b52001-10-22 18:41:51 +00001167- Weak reference objects are now part of the core and offer a C API.
Fred Drake934d2a42001-10-18 18:18:06 +00001168 A bug which could allow a core dump when binary operations involved
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001169 proxy reference has been fixed. weakref.ReferenceError is now a
Barry Warsawf6fb1712001-10-19 05:35:40 +00001170 built-in exception.
Fred Drake934d2a42001-10-18 18:18:06 +00001171
Guido van Rossum1c486092001-10-19 02:05:35 +00001172- unicode(obj) now behaves more like str(obj), accepting arbitrary
1173 objects, and calling a __unicode__ method if it exists.
1174 unicode(obj, encoding) and unicode(obj, encoding, errors) still
Marc-André Lemburgb5507ec2001-10-19 12:02:29 +00001175 require an 8-bit string or character buffer argument.
Guido van Rossum1c486092001-10-19 02:05:35 +00001176
Barry Warsawf6fb1712001-10-19 05:35:40 +00001177- isinstance() now allows any object as the first argument and a
1178 class, a type or something with a __bases__ tuple attribute for the
1179 second argument. The second argument may also be a tuple of a
1180 class, type, or something with __bases__, in which case isinstance()
1181 will return true if the first argument is an instance of any of the
1182 things contained in the second argument tuple. E.g.
1183
1184 isinstance(x, (A, B))
1185
1186 returns true if x is an instance of A or B.
1187
Guido van Rossum9074ef62001-10-16 21:34:49 +00001188Extension modules
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001189-----------------
Guido van Rossum9074ef62001-10-16 21:34:49 +00001190
1191- thread.start_new_thread() now returns the thread ID (previously None).
1192
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001193- binascii has now two quopri support functions, a2b_qp and b2a_qp.
1194
Guido van Rossumc524d952001-10-19 01:31:59 +00001195- readline now supports setting the startup_hook and the
1196 pre_event_hook, and adds the add_history() function.
Martin v. Löwis0daad592001-09-30 21:09:59 +00001197
Guido van Rossumc524d952001-10-19 01:31:59 +00001198- os and posix supports chroot(), setgroups() and unsetenv() where
1199 available. The stat(), fstat(), statvfs() and fstatvfs() functions
1200 now return "pseudo-sequences" -- the various fields can now be
1201 accessed as attributes (e.g. os.stat("/").st_mtime) but for
1202 backwards compatibility they also behave as a fixed-length sequence.
1203 Some platform-specific fields (e.g. st_rdev) are only accessible as
Guido van Rossum98bf58f2001-10-18 20:34:25 +00001204 attributes.
1205
1206- time: localtime(), gmtime() and strptime() now return a
1207 pseudo-sequence similar to the os.stat() return value, with
1208 attributes like tm_year etc.
Martin v. Löwis16628c92001-10-04 22:46:41 +00001209
Guido van Rossum9074ef62001-10-16 21:34:49 +00001210- Decompression objects in the zlib module now accept an optional
1211 second parameter to decompress() that specifies the maximum amount
1212 of memory to use for the uncompressed data.
Tim Petersabf925f2001-09-28 21:53:42 +00001213
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001214- optional SSL support in the socket module now exports OpenSSL
1215 functions RAND_add(), RAND_egd(), and RAND_status(). These calls
1216 are useful on platforms like Solaris where OpenSSL does not
Barry Warsawf6fb1712001-10-19 05:35:40 +00001217 automatically seed its PRNG. Also, the keyfile and certfile
1218 arguments to socket.ssl() are now optional.
1219
1220- posixmodule (and by extension, the os module on POSIX platforms) now
1221 exports O_LARGEFILE, O_DIRECT, O_DIRECTORY, and O_NOFOLLOW.
Jeremy Hyltoncb441432001-10-19 03:40:19 +00001222
Guido van Rossum9074ef62001-10-16 21:34:49 +00001223Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001224-------
Guido van Rossum3c288632001-10-16 21:13:49 +00001225
Tim Peters7402f792001-10-02 03:53:41 +00001226- doctest now excludes functions and classes not defined by the module
1227 being tested, thanks to Tim Hochberg.
1228
Fred Drakecb7a6b52001-10-22 18:41:51 +00001229- HotShot, a new profiler implemented using a C-based callback, has
1230 been added. This substantially reduces the overhead of profiling,
1231 but it is still quite preliminary. Support modules and
1232 documentation will be added in upcoming releases (before 2.2 final).
1233
Guido van Rossumc4b09b42001-10-04 10:19:00 +00001234- profile now produces correct output in situations where an exception
1235 raised in Python is cleared by C code (e.g. hasattr()). This used
1236 to cause wrong output, including spurious claims of recursive
1237 functions and attribution of time spent to the wrong function.
1238
Tim Peters0a1fc4e2001-10-07 03:12:08 +00001239 The code and documentation for the derived OldProfile and HotProfile
1240 profiling classes was removed. The code hasn't worked for years (if
1241 you tried to use them, they raised exceptions). OldProfile
1242 intended to reproduce the behavior of the profiler Python used more
1243 than 7 years ago, and isn't interesting anymore. HotProfile intended
1244 to provide a faster profiler (but producing less information), and
1245 that's a worthy goal we intend to meet via a different approach (but
1246 without losing information).
1247
Tim Peterscce092d2001-10-09 05:31:56 +00001248- Profile.calibrate() has a new implementation that should deliver
Tim Peters659a6032001-10-09 20:51:19 +00001249 a much better system-specific calibration constant. The constant can
1250 now be specified in an instance constructor, or as a Profile class or
1251 instance variable, instead of by editing profile.py's source code.
1252 Calibration must still be done manually (see the docs for the profile
1253 module).
1254
1255 Note that Profile.calibrate() must be overriden by subclasses.
1256 Improving the accuracy required exploiting detailed knowledge of
1257 profiler internals; the earlier method abstracted away the details
1258 and measured a simplified model instead, but consequently computed
1259 a constant too small by a factor of 2 on some modern machines.
Tim Peterscce092d2001-10-09 05:31:56 +00001260
Martin v. Löwis16dc7f42001-09-30 20:32:11 +00001261- quopri's encode and decode methods take an optional header parameter,
Jeremy Hylton6f543b62001-10-16 20:42:52 +00001262 which indicates whether output is intended for the header 'Q'
1263 encoding.
1264
Guido van Rossuma5343cc2001-10-18 18:02:07 +00001265- The SocketServer.ThreadingMixIn class now closes the request after
1266 finish_request() returns. (Not when it errors out though.)
1267
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001268- The nntplib module's NNTP.body() method has grown a 'file' argument
Barry Warsawf6fb1712001-10-19 05:35:40 +00001269 to allow saving the message body to a file.
1270
1271- The email package has added a class email.Parser.HeaderParser which
1272 only parses headers and does not recurse into the message's body.
1273 Also, the module/class MIMEAudio has been added for representing
1274 audio data (contributed by Anthony Baxter).
1275
1276- ftplib should be able to handle files > 2GB.
1277
1278- ConfigParser.getboolean() now also interprets TRUE, FALSE, YES, NO,
1279 ON, and OFF.
1280
Fred Drakecb7a6b52001-10-22 18:41:51 +00001281- xml.dom.minidom NodeList objects now support the length attribute
1282 and item() method as required by the DOM specifications.
1283
Guido van Rossumed554f62001-10-02 23:15:37 +00001284Tools/Demos
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001285-----------
Guido van Rossumed554f62001-10-02 23:15:37 +00001286
1287- Demo/dns was removed. It no longer serves any purpose; a package
1288 derived from it is now maintained by Anthony Baxter, see
1289 http://PyDNS.SourceForge.net.
Tim Petersabf925f2001-09-28 21:53:42 +00001290
Barry Warsawf6fb1712001-10-19 05:35:40 +00001291- The freeze tool has been made more robust, and two new options have
1292 been added: -X and -E.
1293
Tim Petersabf925f2001-09-28 21:53:42 +00001294Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001295-----
Tim Petersabf925f2001-09-28 21:53:42 +00001296
Barry Warsawf6fb1712001-10-19 05:35:40 +00001297- configure will use CXX in LINKCC if CXX is used to build main() and
1298 the system requires to link a C++ main using the C++ compiler.
1299
Tim Petersabf925f2001-09-28 21:53:42 +00001300C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001301-----
Tim Petersabf925f2001-09-28 21:53:42 +00001302
Guido van Rossum6c4bce32001-10-18 19:20:25 +00001303- The documentation for the tp_compare slot is updated to require that
1304 the return value must be -1, 0, 1; an arbitrary number <0 or >0 is
1305 not correct. This is not yet enforced but will be enforced in
1306 Python 2.3; even later, we may use -2 to indicate errors and +2 for
1307 "NotImplemented". Right now, -1 should be used for an error return.
1308
Tim Petersd38b1c72001-09-30 05:09:37 +00001309- PyLong_AsLongLong() now accepts int (as well as long) arguments.
1310 Consequently, PyArg_ParseTuple's 'L' code also accepts int (as well
1311 as long) arguments.
1312
Guido van Rossum3c288632001-10-16 21:13:49 +00001313- PyThread_start_new_thread() now returns a long int giving the thread
1314 ID, if one can be calculated; it returns -1 for error, 0 if no
1315 thread ID is calculated (this is an incompatible change, but only
1316 the thread module used this API). This code has only really been
1317 tested on Linux and Windows; other platforms please beware (and
1318 report any bugs or strange behavior).
1319
Guido van Rossum1c486092001-10-19 02:05:35 +00001320- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
1321 input.
1322
Tim Petersabf925f2001-09-28 21:53:42 +00001323New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001324-------------
Tim Petersabf925f2001-09-28 21:53:42 +00001325
1326Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001327-----
Tim Petersabf925f2001-09-28 21:53:42 +00001328
1329Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001330-------
Tim Petersabf925f2001-09-28 21:53:42 +00001331
Tim Peters04cf1d32001-10-09 22:39:40 +00001332- Installer: If you install IDLE, and don't disable file-extension
1333 registration, a new "Edit with IDLE" context (right-click) menu entry
1334 is created for .py and .pyw files.
1335
Tim Peters1ce3cf72001-10-01 17:58:40 +00001336- The signal module now supports SIGBREAK on Windows, thanks to Steven
1337 Scott. Note that SIGBREAK is unique to Windows. The default SIGBREAK
1338 action remains to call Win32 ExitProcess(). This can be changed via
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001339 signal.signal(). For example: ::
Tim Peters1ce3cf72001-10-01 17:58:40 +00001340
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001341 # Make Ctrl+Break raise KeyboardInterrupt, like Python's default Ctrl+C
1342 # (SIGINT) behavior.
1343 import signal
1344 signal.signal(signal.SIGBREAK, signal.default_int_handler)
Tim Peters1ce3cf72001-10-01 17:58:40 +00001345
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001346 try:
1347 while 1:
1348 pass
1349 except KeyboardInterrupt:
1350 # We get here on Ctrl+C or Ctrl+Break now; if we had not changed
1351 # SIGBREAK, only on Ctrl+C (and Ctrl+Break would terminate the
1352 # program without the possibility for any Python-level cleanup).
1353 print "Clean exit"
Tim Peters1ce3cf72001-10-01 17:58:40 +00001354
Tim Petersabf925f2001-09-28 21:53:42 +00001355
Tim Petersb07352e2001-09-08 01:25:47 +00001356What's New in Python 2.2a4?
1357===========================
1358
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001359*Release date: 28-Sep-2001*
1360
Guido van Rossum808eea72001-09-25 04:15:41 +00001361Type/class unification and new-style classes
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001362--------------------------------------------
Guido van Rossum808eea72001-09-25 04:15:41 +00001363
1364- pydoc and inspect are now aware of new-style classes;
1365 e.g. help(list) at the interactive prompt now shows proper
1366 documentation for all operations on list objects.
1367
1368- Applications using Jim Fulton's ExtensionClass module can now safely
1369 be used with Python 2.2. In particular, Zope 2.4.1 now works with
1370 Python 2.2 (as well as with Python 2.1.1). The Demo/metaclass
1371 examples also work again. It is hoped that Gtk and Boost also work
1372 with 2.2a4 and beyond. (If you can confirm this, please write
1373 webmaster@python.org; if there are still problems, please open a bug
1374 report on SourceForge.)
Tim Petersb07352e2001-09-08 01:25:47 +00001375
Tim Peters66c1a522001-09-24 21:17:50 +00001376- property() now takes 4 keyword arguments: fget, fset, fdel and doc.
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001377 These map to read-only attributes 'fget', 'fset', 'fdel', and '__doc__'
Tim Peters66c1a522001-09-24 21:17:50 +00001378 in the constructed property object. fget, fset and fdel weren't
1379 discoverable from Python in 2.2a3. __doc__ is new, and allows to
1380 associate a docstring with a property.
1381
Guido van Rossum808eea72001-09-25 04:15:41 +00001382- Comparison overloading is now more completely implemented. For
1383 example, a str subclass instance can properly be compared to a str
1384 instance, and it can properly overload comparison. Ditto for most
1385 other built-in object types.
1386
1387- The repr() of new-style classes has changed; instead of <type
1388 'M.Foo'> a new-style class is now rendered as <class 'M.Foo'>,
1389 *except* for built-in types, which are still rendered as <type
1390 'Foo'> (to avoid upsetting existing code that might parse or
1391 otherwise rely on repr() of certain type objects).
1392
1393- The repr() of new-style objects is now always <Foo object at XXX>;
1394 previously, it was sometimes <Foo instance at XXX>.
1395
1396- For new-style classes, what was previously called __getattr__ is now
1397 called __getattribute__. This method, if defined, is called for
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001398 *every* attribute access. A new __getattr__ hook more similar to the
Guido van Rossum808eea72001-09-25 04:15:41 +00001399 one in classic classes is defined which is called only if regular
1400 attribute access raises AttributeError; to catch *all* attribute
1401 access, you can use __getattribute__ (for new-style classes). If
1402 both are defined, __getattribute__ is called first, and if it raises
1403 AttributeError, __getattr__ is called.
1404
1405- The __class__ attribute of new-style objects can be assigned to.
1406 The new class must have the same C-level object layout as the old
1407 class.
1408
1409- The builtin file type can be subclassed now. In the usual pattern,
1410 "file" is the name of the builtin type, and file() is a new builtin
1411 constructor, with the same signature as the builtin open() function.
1412 file() is now the preferred way to open a file.
1413
1414- Previously, __new__ would only see sequential arguments passed to
1415 the type in a constructor call; __init__ would see both sequential
1416 and keyword arguments. This made no sense whatsoever any more, so
1417 now both __new__ and __init__ see all arguments.
1418
1419- Previously, hash() applied to an instance of a subclass of str or
1420 unicode always returned 0. This has been repaired.
1421
1422- Previously, an operation on an instance of a subclass of an
1423 immutable type (int, long, float, complex, tuple, str, unicode),
1424 where the subtype didn't override the operation (and so the
1425 operation was handled by the builtin type), could return that
1426 instance instead a value of the base type. For example, if s was of
Andrew M. Kuchling21b23b02002-05-07 20:58:03 +00001427 a str subclass type, s[:] returned s as-is. Now it returns a str
Guido van Rossum808eea72001-09-25 04:15:41 +00001428 with the same value as s.
1429
Barry Warsaw86fbaf82001-09-28 15:26:12 +00001430- Provisional support for pickling new-style objects has been added.
1431
Guido van Rossum808eea72001-09-25 04:15:41 +00001432Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001433----
Guido van Rossum808eea72001-09-25 04:15:41 +00001434
Tim Peters2c9aa5e2001-09-23 04:06:05 +00001435- file.writelines() now accepts any iterable object producing strings.
1436
Marc-André Lemburgaefd7662001-09-20 12:59:37 +00001437- PyUnicode_FromEncodedObject() now works very much like
1438 PyObject_Str(obj) in that it tries to use __str__/tp_str
1439 on the object if the object is not a string or buffer. This
1440 makes unicode() behave like str() when applied to non-string/buffer
1441 objects.
1442
Andrew M. Kuchling51c18162001-10-22 01:47:26 +00001443- PyFile_WriteObject now passes Unicode objects to the file's write
1444 method. As a result, all file-like objects which may be the target
Martin v. Löwis2777c022001-09-19 13:47:32 +00001445 of a print statement must support Unicode objects, i.e. they must
1446 at least convert them into ASCII strings.
1447
Guido van Rossum624c8af2001-09-18 15:21:04 +00001448- Thread scheduling on Solaris should be improved; it is no longer
1449 necessary to insert a small sleep at the start of a thread in order
1450 to let other runnable threads be scheduled.
1451
Tim Petersb07352e2001-09-08 01:25:47 +00001452Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001453-------
Tim Petersb07352e2001-09-08 01:25:47 +00001454
Marc-André Lemburgbf990172001-09-27 14:17:33 +00001455- StringIO.StringIO instances and cStringIO.StringIO instances support
1456 read character buffer compatible objects for their .write() methods.
1457 These objects are converted to strings and then handled as such
1458 by the instances.
1459
Barry Warsaw2f600732001-09-24 04:28:10 +00001460- The "email" package has been added. This is basically a port of the
1461 mimelib package <http://sf.net/projects/mimelib> with API changes
1462 and some implementations updated to use iterators and generators.
1463
Tim Peters8a9c2842001-09-22 21:30:22 +00001464- difflib.ndiff() and difflib.Differ.compare() are generators now. This
1465 restores the ability of Tools/scripts/ndiff.py to start producing output
1466 before the entire comparison is complete.
1467
Barry Warsaw58b072d2001-09-22 04:44:21 +00001468- StringIO.StringIO instances and cStringIO.StringIO instances support
1469 iteration just like file objects (i.e. their .readline() method is
1470 called for each iteration until it returns an empty string).
1471
Marc-André Lemburg494f2ae2001-09-19 11:33:31 +00001472- The codecs module has grown four new helper APIs to access
1473 builtin codecs: getencoder(), getdecoder(), getreader(),
1474 getwriter().
1475
Guido van Rossum624c8af2001-09-18 15:21:04 +00001476- SimpleXMLRPCServer: a new module (based upon SimpleHTMLServer)
1477 simplifies writing XML RPC servers.
1478
Barry Warsaw647d5e82001-09-28 17:01:02 +00001479- os.path.realpath(): a new function that returns the absolute pathname
Guido van Rossum624c8af2001-09-18 15:21:04 +00001480 after interpretation of symbolic links. On non-Unix systems, this
1481 is an alias for os.path.abspath().
1482
Tim Peters16a77ad2001-09-08 04:00:12 +00001483- operator.indexOf() (PySequence_Index() in the C API) now works with any
1484 iterable object.
1485
Guido van Rossum624c8af2001-09-18 15:21:04 +00001486- smtplib now supports various authentication and security features of
1487 the SMTP protocol through the new login() and starttls() methods.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00001488
Guido van Rossum624c8af2001-09-18 15:21:04 +00001489- hmac: a new module implementing keyed hashing for message
1490 authentication.
1491
1492- mimetypes now recognizes more extensions and file types. At the
1493 same time, some mappings not sanctioned by IANA were removed.
Guido van Rossumd8185ca2001-09-14 16:35:16 +00001494
Guido van Rossum624c8af2001-09-18 15:21:04 +00001495- The "compiler" package has been brought up to date to the state of
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00001496 Python 2.2 bytecode generation. It has also been promoted from a
1497 Tool to a standard library package. (Tools/compiler still exists as
1498 a sample driver.)
1499
Guido van Rossumc9ed5dc2001-09-20 05:30:24 +00001500Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001501-----
Guido van Rossum624c8af2001-09-18 15:21:04 +00001502
Tim Petersb07352e2001-09-08 01:25:47 +00001503Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001504-----
Tim Petersb07352e2001-09-08 01:25:47 +00001505
Guido van Rossum624c8af2001-09-18 15:21:04 +00001506- Large file support (LFS) is now automatic when the platform supports
1507 it; no more manual configuration tweaks are needed. On Linux, at
1508 least, it's possible to have a system whose C library supports large
1509 files but whose kernel doesn't; in this case, large file support is
1510 still enabled but doesn't do you any good unless you upgrade your
1511 kernel or share your Python executable with another system whose
1512 kernel has large file support.
1513
1514- The configure script now supplies plausible defaults in a
1515 cross-compilation environment. This doesn't mean that the supplied
1516 values are always correct, or that cross-compilation now works
1517 flawlessly -- but it's a first step (and it shuts up most of
1518 autoconf's warnings about AC_TRY_RUN).
1519
1520- The Unix build is now a bit less chatty, courtesy of the parser
1521 generator. The build is completely silent (except for errors) when
1522 using "make -s", thanks to a -q option to setup.py.
1523
Tim Petersb07352e2001-09-08 01:25:47 +00001524C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001525-----
Tim Petersb07352e2001-09-08 01:25:47 +00001526
Guido van Rossum624c8af2001-09-18 15:21:04 +00001527- The "structmember" API now supports some new flag bits to deny read
1528 and/or write access to attributes in restricted execution mode.
1529
Tim Petersb07352e2001-09-08 01:25:47 +00001530New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001531-------------
Tim Petersb07352e2001-09-08 01:25:47 +00001532
Guido van Rossum624c8af2001-09-18 15:21:04 +00001533- Compaq's iPAQ handheld, running the "familiar" Linux distribution
1534 (http://familiar.handhelds.org).
1535
Tim Petersb07352e2001-09-08 01:25:47 +00001536Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001537-----
Tim Petersb07352e2001-09-08 01:25:47 +00001538
Tim Peters8a9c2842001-09-22 21:30:22 +00001539- The "classic" standard tests, which work by comparing stdout to
1540 an expected-output file under Lib/test/output/, no longer stop at
1541 the first mismatch. Instead the test is run to completion, and a
1542 variant of ndiff-style comparison is used to report all differences.
1543 This is much easier to understand than the previous style of reporting.
1544
1545- The unittest-based standard tests now use regrtest's test_main()
1546 convention, instead of running as a side-effect of merely being
1547 imported. This allows these tests to be run in more natural and
1548 flexible ways as unittests, outside the regrtest framework.
1549
1550- regrtest.py is much better integrated with unittest and doctest now,
1551 especially in regard to reporting errors.
1552
Tim Petersb07352e2001-09-08 01:25:47 +00001553Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001554-------
Tim Petersb07352e2001-09-08 01:25:47 +00001555
Guido van Rossum624c8af2001-09-18 15:21:04 +00001556- Large file support now also works for files > 4GB, on filesystems
Tim Peters8a9c2842001-09-22 21:30:22 +00001557 that support it (NTFS under Windows 2000). See "What's New in
1558 Python 2.2a3" for more detail.
Guido van Rossum624c8af2001-09-18 15:21:04 +00001559
Tim Petersb07352e2001-09-08 01:25:47 +00001560
Tim Petersedc99312001-08-22 21:36:50 +00001561What's New in Python 2.2a3?
1562===========================
1563
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001564*Release Date: 07-Sep-2001*
1565
Tim Petersedc99312001-08-22 21:36:50 +00001566Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001567----
Tim Petersedc99312001-08-22 21:36:50 +00001568
Tim Peters9fffa3e2001-09-04 05:14:19 +00001569- Conversion of long to float now raises OverflowError if the long is too
1570 big to represent as a C double.
1571
Tim Peters32f453e2001-09-03 08:35:41 +00001572- The 3-argument builtin pow() no longer allows a third non-None argument
1573 if either of the first two arguments is a float, or if both are of
1574 integer types and the second argument is negative (in which latter case
1575 the arguments are converted to float, so this is really the same
1576 restriction).
1577
Tim Peters5d2b77c2001-09-03 05:47:38 +00001578- The builtin dir() now returns more information, and sometimes much
1579 more, generally naming all attributes of an object, and all attributes
1580 reachable from the object via its class, and from its class's base
1581 classes, and so on from them too. Example: in 2.2a2, dir([]) returned
1582 an empty list. In 2.2a3,
1583
1584 >>> dir([])
1585 ['__add__', '__class__', '__contains__', '__delattr__', '__delitem__',
1586 '__eq__', '__ge__', '__getattr__', '__getitem__', '__getslice__',
1587 '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__le__',
1588 '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__repr__',
1589 '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__str__',
1590 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove',
1591 'reverse', 'sort']
1592
1593 dir(module) continues to return only the module's attributes, though.
1594
Tim Petersbdee63f2001-09-02 03:40:59 +00001595- Overflowing operations on plain ints now return a long int rather
Guido van Rossumae457142001-08-31 18:31:35 +00001596 than raising OverflowError. This is a partial implementation of PEP
1597 237. You can use -Wdefault::OverflowWarning to enable a warning for
1598 this situation, and -Werror::OverflowWarning to revert to the old
1599 OverflowError exception.
1600
Guido van Rossum61c345f2001-09-04 03:26:15 +00001601- A new command line option, -Q<arg>, is added to control run-time
Guido van Rossumae457142001-08-31 18:31:35 +00001602 warnings for the use of classic division. (See PEP 238.) Possible
Barry Warsawd6c8ca62001-09-07 18:13:44 +00001603 values are -Qold, -Qwarn, -Qwarnall, and -Qnew. The default is
1604 -Qold, meaning the / operator has its classic meaning and no
1605 warnings are issued. Using -Qwarn issues a run-time warning about
1606 all uses of classic division for int and long arguments; -Qwarnall
1607 also warns about classic division for float and complex arguments
Tim Peters3caca232001-12-06 06:23:26 +00001608 (for use with fixdiv.py).
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001609 [Note: the remainder of this item (preserved below) became
1610 obsolete in 2.2c1 -- -Qnew has global effect in 2.2] ::
1611
1612 Using -Qnew is questionable; it turns on new division by default, but
1613 only in the __main__ module. You can usefully combine -Qwarn or
1614 -Qwarnall and -Qnew: this gives the __main__ module new division, and
1615 warns about classic division everywhere else.
Guido van Rossumae457142001-08-31 18:31:35 +00001616
Tim Petersbdee63f2001-09-02 03:40:59 +00001617- Many built-in types can now be subclassed. This applies to int,
Guido van Rossumae457142001-08-31 18:31:35 +00001618 long, float, str, unicode, and tuple. (The types complex, list and
1619 dictionary can also be subclassed; this was introduced earlier.)
1620 Note that restrictions apply when subclassing immutable built-in
1621 types: you can only affect the value of the instance by overloading
1622 __new__. You can add mutable attributes, and the subclass instances
1623 will have a __dict__ attribute, but you cannot change the "value"
1624 (as implemented by the base class) of an immutable subclass instance
1625 once it is created.
1626
Guido van Rossumaaf80c82001-09-02 13:44:35 +00001627- The dictionary constructor now takes an optional argument, a
1628 mapping-like object, and initializes the dictionary from its
1629 (key, value) pairs.
1630
Tim Petersbdee63f2001-09-02 03:40:59 +00001631- A new built-in type, super, has been added. This facilitates making
Guido van Rossumae457142001-08-31 18:31:35 +00001632 "cooperative super calls" in a multiple inheritance setting. For an
1633 explanation, see http://www.python.org/2.2/descrintro.html#cooperation
1634
Guido van Rossum8d7234d2001-09-06 22:02:58 +00001635- A new built-in type, property, has been added. This enables the
1636 creation of "properties". These are attributes implemented by
1637 getter and setter functions (or only one of these for read-only or
1638 write-only attributes), without the need to override __getattr__.
1639 See http://www.python.org/2.2/descrintro.html#property
Guido van Rossumae457142001-08-31 18:31:35 +00001640
Tim Petersbdee63f2001-09-02 03:40:59 +00001641- The syntax of floating-point and imaginary literals has been
Tim Petersd507dab2001-08-30 20:51:59 +00001642 liberalized, to allow leading zeroes. Examples of literals now
1643 legal that were SyntaxErrors before:
1644
1645 00.0 0e3 0100j 07.5 00000000000000000008.
1646
Tim Petersbdee63f2001-09-02 03:40:59 +00001647- An old tokenizer bug allowed floating point literals with an incomplete
Tim Petersc6d95812001-08-28 20:56:27 +00001648 exponent, such as 1e and 3.1e-. Such literals now raise SyntaxError.
1649
Tim Petersedc99312001-08-22 21:36:50 +00001650Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001651-------
Tim Petersedc99312001-08-22 21:36:50 +00001652
Martin v. Löwiscb227c92001-09-06 08:54:16 +00001653- telnetlib includes symbolic names for the options, and support for
1654 setting an option negotiation callback.
1655
Tim Petersa40c7932001-09-05 22:36:56 +00001656- The new C standard no longer requires that math libraries set errno to
1657 ERANGE on overflow. For platform libraries that exploit this new
1658 freedom, Python's overflow-checking was wholly broken. A new overflow-
1659 checking scheme attempts to repair that, but may not be reliable on all
1660 platforms (C doesn't seem to provide anything both useful and portable
1661 in this area anymore).
1662
Martin v. Löwis44f86962001-09-05 13:44:54 +00001663- Asynchronous timeout actions are available through the new class
1664 threading.Timer.
1665
Tim Peters78526162001-09-05 00:53:45 +00001666- math.log and math.log10 now return sensible results for even huge
1667 long arguments. For example, math.log10(10 ** 10000) ~= 10000.0.
1668
Tim Petersbdee63f2001-09-02 03:40:59 +00001669- A new function, imp.lock_held(), returns 1 when the import lock is
Tim Peters69232342001-08-30 05:16:13 +00001670 currently held. See the docs for the imp module.
1671
Tim Petersbdee63f2001-09-02 03:40:59 +00001672- pickle, cPickle and marshal on 32-bit platforms can now correctly read
Tim Peters82112372001-08-29 02:28:42 +00001673 dumps containing ints written on platforms where Python ints are 8 bytes.
1674 When read on a box where Python ints are 4 bytes, such values are
1675 converted to Python longs.
1676
Tim Petersbdee63f2001-09-02 03:40:59 +00001677- In restricted execution mode (using the rexec module), unmarshalling
Guido van Rossumae457142001-08-31 18:31:35 +00001678 code objects is no longer allowed. This plugs a security hole.
1679
Steve Purcell6091cd62001-09-06 16:05:17 +00001680- unittest.TestResult instances no longer store references to tracebacks
1681 generated by test failures. This prevents unexpected dangling references
1682 to objects that should be garbage collected between tests.
1683
Tim Petersedc99312001-08-22 21:36:50 +00001684Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001685-----
Tim Petersedc99312001-08-22 21:36:50 +00001686
Barry Warsawd6c8ca62001-09-07 18:13:44 +00001687- Tools/scripts/fixdiv.py has been added which can be used to fix
1688 division operators as per PEP 238.
1689
Tim Petersedc99312001-08-22 21:36:50 +00001690Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001691-----
Tim Petersedc99312001-08-22 21:36:50 +00001692
Barry Warsawd6c8ca62001-09-07 18:13:44 +00001693- If you are an adventurous person using Mac OS X you may want to look at
1694 Mac/OSX. There is a Makefile there that will build Python as a real Mac
1695 application, which can be used for experimenting with Carbon or Cocoa.
1696 Discussion of this on pythonmac-sig, please.
1697
Tim Peters7eea37e2001-09-04 22:08:56 +00001698C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001699-----
Tim Peters7eea37e2001-09-04 22:08:56 +00001700
1701- New function PyObject_Dir(obj), like Python __builtin__.dir(obj).
Tim Peters69232342001-08-30 05:16:13 +00001702
Tim Peters9fffa3e2001-09-04 05:14:19 +00001703- Note that PyLong_AsDouble can fail! This has always been true, but no
1704 callers checked for it. It's more likely to fail now, because overflow
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001705 errors are properly detected now. The proper way to check: ::
Tim Peters9fffa3e2001-09-04 05:14:19 +00001706
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001707 double x = PyLong_AsDouble(some_long_object);
1708 if (x == -1.0 && PyErr_Occurred()) {
1709 /* The conversion failed. */
1710 }
Tim Peters9fffa3e2001-09-04 05:14:19 +00001711
Tim Petersbdee63f2001-09-02 03:40:59 +00001712- The GC API has been changed. Extensions that use the old API will still
Neil Schemenauer4042c692001-08-30 15:38:01 +00001713 compile but will not participate in GC. To upgrade an extension
1714 module:
1715
1716 - rename Py_TPFLAGS_GC to PyTPFLAGS_HAVE_GC
Tim Petersd507dab2001-08-30 20:51:59 +00001717
Neil Schemenauer4042c692001-08-30 15:38:01 +00001718 - use PyObject_GC_New or PyObject_GC_NewVar to allocate objects and
1719 PyObject_GC_Del to deallocate them
Tim Petersd507dab2001-08-30 20:51:59 +00001720
Neil Schemenauer4042c692001-08-30 15:38:01 +00001721 - rename PyObject_GC_Init to PyObject_GC_Track and PyObject_GC_Fini
1722 to PyObject_GC_UnTrack
Tim Petersd507dab2001-08-30 20:51:59 +00001723
Neil Schemenauer4042c692001-08-30 15:38:01 +00001724 - remove PyGC_HEAD_SIZE from object size calculations
1725
1726 - remove calls to PyObject_AS_GC and PyObject_FROM_GC
1727
Tim Petersbdee63f2001-09-02 03:40:59 +00001728- Two new functions: PyString_FromFormat() and PyString_FromFormatV().
Guido van Rossumae457142001-08-31 18:31:35 +00001729 These can be used safely to construct string objects from a
1730 sprintf-style format string (similar to the format string supported
1731 by PyErr_Format()).
Tim Peters69232342001-08-30 05:16:13 +00001732
Tim Petersedc99312001-08-22 21:36:50 +00001733New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001734-------------
Tim Petersedc99312001-08-22 21:36:50 +00001735
Tim Petersb7da0902001-09-02 23:01:43 +00001736- Stephen Hansen contributed patches sufficient to get a clean compile
1737 under Borland C (Windows), but he reports problems running it and ran
1738 out of time to complete the port. Volunteers? Expect a MemoryError
1739 when importing the types module; this is probably shallow, and
1740 causing later failures too.
Tim Petersbdee63f2001-09-02 03:40:59 +00001741
Tim Petersedc99312001-08-22 21:36:50 +00001742Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001743-----
Tim Petersedc99312001-08-22 21:36:50 +00001744
1745Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001746-------
Tim Petersedc99312001-08-22 21:36:50 +00001747
Tim Peters6e13a562001-09-06 00:32:15 +00001748- Large file support is now enabled on Win32 platforms as well as on
1749 Win64. This means that, for example, you can use f.tell() and f.seek()
1750 to manipulate files larger than 2 gigabytes (provided you have enough
1751 disk space, and are using a Windows filesystem that supports large
Tim Peters9a9471c2001-09-11 23:18:51 +00001752 partitions). Windows filesystem limits: FAT has a 2GB (gigabyte)
1753 filesize limit, and large file support makes no difference there.
1754 FAT32's limit is 4GB, and files >= 2GB are easier to use from Python now.
1755 NTFS has no practical limit on file size, and files of any size can be
1756 used from Python now.
Tim Peters6e13a562001-09-06 00:32:15 +00001757
Tim Petersbdee63f2001-09-02 03:40:59 +00001758- The w9xpopen hack is now used on Windows NT and 2000 too when COMPSPEC
Tim Peters402d5982001-08-27 06:37:48 +00001759 points to command.com (patch from Brian Quinlan).
1760
Tim Petersedc99312001-08-22 21:36:50 +00001761
Tim Peters20f51a72001-07-21 02:31:40 +00001762What's New in Python 2.2a2?
1763===========================
1764
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001765*Release Date: 22-Aug-2001*
1766
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001767Build
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001768-----
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001769
Barry Warsaw18b2ecf2001-08-22 20:26:56 +00001770- Tim Peters developed a brand new Windows installer using Wise 8.1,
1771 generously donated to us by Wise Solutions.
1772
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001773- configure supports a new option --enable-unicode, with the values
1774 ucs2 and ucs4 (new in 2.2a1). With --disable-unicode, the Unicode
1775 type and supporting code is completely removed from the interpreter.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001776
Jack Jansen32ce0cd2001-08-21 19:28:20 +00001777- A new configure option --enable-framework builds a Mac OS X framework,
1778 which "make frameworkinstall" will install. This provides a starting
1779 point for more mac-like functionality, join pythonmac-sig@python.org
1780 if you are interested in helping.
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001781
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001782- The NeXT platform is no longer supported.
1783
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001784- The 'new' module is now statically linked.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001785
Tim Peters0afb6092001-08-15 06:06:44 +00001786Tools
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001787-----
Tim Peters0afb6092001-08-15 06:06:44 +00001788
1789- The new Tools/scripts/cleanfuture.py can be used to automatically
Andrew M. Kuchlingb0532092001-08-15 15:54:56 +00001790 edit out obsolete future statements from Python source code. See
Tim Peters0afb6092001-08-15 06:06:44 +00001791 the module docstring for details.
1792
Tim Peters20f51a72001-07-21 02:31:40 +00001793Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001794-----
Tim Peters20f51a72001-07-21 02:31:40 +00001795
Tim Peters5e824c32001-08-12 22:25:01 +00001796- regrtest.py now knows which tests are expected to be skipped on some
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001797 platforms, allowing to give clearer test result output. regrtest
1798 also has optional --use/-u switch to run normally disabled tests
1799 which require network access or consume significant disk resources.
Tim Peters5e824c32001-08-12 22:25:01 +00001800
Tim Peters20f51a72001-07-21 02:31:40 +00001801- Several new tests in the standard test suite, with special thanks to
1802 Nick Mathewson.
1803
1804Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001805----
Tim Peters20f51a72001-07-21 02:31:40 +00001806
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001807- The floor division operator // has been added as outlined in PEP
1808 238. The / operator still provides classic division (and will until
1809 Python 3.0) unless "from __future__ import division" is included, in
1810 which case the / operator will provide true division. The operator
1811 module provides truediv() and floordiv() functions. Augmented
1812 assignment variants are included, as are the equivalent overloadable
1813 methods and C API methods. See the PEP for a full discussion:
1814 <http://python.sf.net/peps/pep-0238.html>
1815
Tim Peters6cd6a822001-08-17 22:11:27 +00001816- Future statements are now effective in simulated interactive shells
1817 (like IDLE). This should "just work" by magic, but read Michael
1818 Hudson's "Future statements in simulated shells" PEP 264 for full
1819 details: <http://python.sf.net/peps/pep-0264.html>.
1820
Guido van Rossumf86ddd22001-08-17 21:21:04 +00001821- The type/class unification (PEP 252-253) was integrated into the
1822 trunk and is not so tentative any more (the exact specification of
1823 some features is still tentative). A lot of work has done on fixing
1824 bugs and adding robustness and features (performance still has to
1825 come a long way).
1826
Marc-André Lemburg888fac02001-07-31 14:24:31 +00001827- Warnings about a mismatch in the Python API during extension import
1828 now use the Python warning framework (which makes it possible to
1829 write filters for these warnings).
1830
Barry Warsaw9b3be7f2001-08-14 18:35:02 +00001831- A function's __dict__ (aka func_dict) will now always be a
1832 dictionary. It used to be possible to delete it or set it to None,
1833 but now both actions raise TypeErrors. It is still legal to set it
1834 to a dictionary object. Getting func.__dict__ before any attributes
1835 have been assigned now returns an empty dictionary instead of None.
1836
Guido van Rossum32aa5d22001-09-05 18:43:35 +00001837- A new command line option, -E, was added which disables the use of
1838 all environment variables, or at least those that are specifically
1839 significant to Python. Usually those have a name starting with
1840 "PYTHON". This was used to fix a problem where the tests fail if
1841 the user happens to have PYTHONHOME or PYTHONPATH pointing to an
1842 older distribution.
1843
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001844Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001845-------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001846
Tim Peters5e824c32001-08-12 22:25:01 +00001847- New class Differ and new functions ndiff() and restore() in difflib.py.
1848 These package the algorithms used by the popular Tools/scripts/ndiff.py,
Tim Peters0afb6092001-08-15 06:06:44 +00001849 for programmatic reuse.
Tim Peters5e824c32001-08-12 22:25:01 +00001850
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001851- New function xml.sax.saxutils.quoteattr(): Quote an XML attribute
1852 value using the minimal quoting required for the value; more
1853 reliable than using xml.sax.saxutils.escape() for attribute values.
1854
1855- Readline completion support for cmd.Cmd was added.
1856
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001857- Calling os.tempnam() or os.tmpnam() generate RuntimeWarnings.
1858
1859- Added function threading.BoundedSemaphore()
1860
1861- Added Ka-Ping Yee's cgitb.py module.
1862
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001863- The 'new' module now exposes the CO_xxx flags.
Barry Warsaw6f3410d2001-08-22 04:08:41 +00001864
Martin v. Löwis560da622001-11-24 09:24:51 +00001865- The gc module offers the get_referents function.
1866
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001867New platforms
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001868-------------
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001869
1870C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001871-----
Marc-André Lemburgd6277912001-07-31 14:42:42 +00001872
Marc-André Lemburg888fac02001-07-31 14:24:31 +00001873- Two new APIs PyOS_snprintf() and PyOS_vsnprintf() were added
1874 which provide a cross-platform implementations for the
1875 relatively new snprintf()/vsnprintf() C lib APIs. In contrast to
1876 the standard sprintf() and vsprintf() C lib APIs, these versions
1877 apply bounds checking on the used buffer which enhances protection
1878 against buffer overruns.
1879
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00001880- Unicode APIs now use name mangling to assure that mixing interpreters
Tim Petersc1731372001-08-04 08:12:36 +00001881 and extensions using different Unicode widths is rendered next to
1882 impossible. Trying to import an incompatible Unicode-aware extension
Marc-André Lemburg48dbfe92001-07-31 14:37:40 +00001883 will result in an ImportError. Unicode extensions writers must make
1884 sure to check the Unicode width compatibility in their extensions by
1885 using at least one of the mangled Unicode APIs in the extension.
1886
Martin v. Löwis339d0f72001-08-17 18:39:25 +00001887- Two new flags METH_NOARGS and METH_O are available in method definition
1888 tables to simplify implementation of methods with no arguments and a
1889 single untyped argument. Calling such methods is more efficient than
1890 calling corresponding METH_VARARGS methods. METH_OLDARGS is now
1891 deprecated.
1892
Tim Petersc1731372001-08-04 08:12:36 +00001893Windows
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001894-------
Tim Petersc1731372001-08-04 08:12:36 +00001895
1896- "import module" now compiles module.pyw if it exists and nothing else
1897 relevant is found.
1898
Tim Peters20f51a72001-07-21 02:31:40 +00001899
Guido van Rossum55a78992001-07-17 17:22:32 +00001900What's New in Python 2.2a1?
Tim Petersf553f892001-05-01 20:45:31 +00001901===========================
1902
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001903*Release date: 18-Jul-2001*
1904
Tim Petersf553f892001-05-01 20:45:31 +00001905Core
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001906----
Tim Petersa814db52001-05-14 07:05:58 +00001907
Tim Peters6d6c1a32001-08-02 04:15:00 +00001908- TENTATIVELY, a large amount of code implementing much of what's
1909 described in PEP 252 (Making Types Look More Like Classes) and PEP
1910 253 (Subtyping Built-in Types) was added. This will be released
1911 with Python 2.2a1. Documentation will be provided separately
1912 through http://www.python.org/2.2/. The purpose of releasing this
1913 with Python 2.2a1 is to test backwards compatibility. It is
1914 possible, though not likely, that a decision is made not to release
1915 this code as part of 2.2 final, if any serious backwards
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00001916 incompatibilities are found during alpha testing that cannot be
Tim Peters6d6c1a32001-08-02 04:15:00 +00001917 repaired.
1918
Guido van Rossum55a78992001-07-17 17:22:32 +00001919- Generators were added; this is a new way to create an iterator (see
Tim Peters11a0d102001-07-17 18:48:00 +00001920 below) using what looks like a simple function containing one or
Guido van Rossum55a78992001-07-17 17:22:32 +00001921 more 'yield' statements. See PEP 255. Since this adds a new
1922 keyword to the language, this feature must be enabled by including a
1923 future statement: "from __future__ import generators" (see PEP 236).
1924 Generators will become a standard feature in a future release
1925 (probably 2.3). Without this future statement, 'yield' remains an
1926 ordinary identifier, but a warning is issued each time it is used.
1927 (These warnings currently don't conform to the warnings framework of
1928 PEP 230; we intend to fix this in 2.2a2.)
1929
Marc-André Lemburg12e74b32001-05-22 08:58:23 +00001930- The UTF-16 codec was modified to be more RFC compliant. It will now
1931 only remove BOM characters at the start of the string and then
1932 only if running in native mode (UTF-16-LE and -BE won't remove a
1933 leading BMO character).
1934
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00001935- Strings now have a new method .decode() to complement the already
1936 existing .encode() method. These two methods provide direct access
1937 to the corresponding decoders and encoders of the registered codecs.
1938
1939 To enhance the usability of the .encode() method, the special
1940 casing of Unicode object return values was dropped (Unicode objects
1941 were auto-magically converted to string using the default encoding).
Tim Peterseb28ef22001-06-02 05:27:19 +00001942
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00001943 Both methods will now return whatever the codec in charge of the
1944 requested encoding returns as object, e.g. Unicode codecs will
1945 return Unicode objects when decoding is requested ("äöü".decode("latin-1")
1946 will return u"äöü"). This enables codec writer to create codecs
1947 for various simple to use conversions.
1948
1949 New codecs were added to demonstrate these new features (the .encode()
1950 and .decode() columns indicate the type of the returned objects):
1951
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00001952 +---------+-----------+-----------+-----------------------------+
1953 |Name | .encode() | .decode() | Description |
1954 +=========+===========+===========+=============================+
1955 |uu | string | string | UU codec (e.g. for email) |
1956 +---------+-----------+-----------+-----------------------------+
1957 |base64 | string | string | base64 codec |
1958 +---------+-----------+-----------+-----------------------------+
1959 |quopri | string | string | quoted-printable codec |
1960 +---------+-----------+-----------+-----------------------------+
1961 |zlib | string | string | zlib compression |
1962 +---------+-----------+-----------+-----------------------------+
1963 |hex | string | string | 2-byte hex codec |
1964 +---------+-----------+-----------+-----------------------------+
1965 |rot-13 | string | Unicode | ROT-13 Unicode charmap codec|
1966 +---------+-----------+-----------+-----------------------------+
Marc-André Lemburgfab96cc2001-05-15 18:38:45 +00001967
Mark Hammond2a0af792001-05-14 03:09:36 +00001968- Some operating systems now support the concept of a default Unicode
1969 encoding for file system operations. Notably, Windows supports 'mbcs'
1970 as the default. The Macintosh will also adopt this concept in the medium
Guido van Rossum1bd797a2001-05-14 13:53:38 +00001971 term, although the default encoding for that platform will be other than
Mark Hammond2a0af792001-05-14 03:09:36 +00001972 'mbcs'.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00001973
1974 On operating system that support non-ASCII filenames, it is common for
Mark Hammond2a0af792001-05-14 03:09:36 +00001975 functions that return filenames (such as os.listdir()) to return Python
1976 string objects pre-encoded using the default file system encoding for
1977 the platform. As this encoding is likely to be different from Python's
1978 default encoding, converting this name to a Unicode object before passing
1979 it back to the Operating System would result in a Unicode error, as Python
Tim Petersa814db52001-05-14 07:05:58 +00001980 would attempt to use its default encoding (generally ASCII) rather than
1981 the default encoding for the file system.
Guido van Rossum1bd797a2001-05-14 13:53:38 +00001982
Tim Petersa814db52001-05-14 07:05:58 +00001983 In general, this change simply removes surprises when working with
1984 Unicode and the file system, making these operations work as you expect,
1985 increasing the transparency of Unicode objects in this context.
Mark Hammond2a0af792001-05-14 03:09:36 +00001986 See [????] for more details, including examples.
Tim Petersf553f892001-05-01 20:45:31 +00001987
Tim Peters61dff2b2001-05-08 15:43:37 +00001988- Float (and complex) literals in source code were evaluated to full
1989 precision only when running from a .py file; the same code loaded from a
1990 .pyc (or .pyo) file could suffer numeric differences starting at about the
1991 12th significant decimal digit. For example, on a machine with IEEE-754
1992 floating arithmetic,
1993
1994 x = 9007199254740992.0
1995 print long(x)
1996
1997 printed 9007199254740992 if run directly from .py, but 9007199254740000
1998 if from a compiled (.pyc or .pyo) file. This was due to marshal using
1999 str(float) instead of repr(float) when building code objects. marshal
2000 now uses repr(float) instead, which should reproduce floats to full
2001 machine precision (assuming the platform C float<->string I/O conversion
2002 functions are of good quality).
2003
2004 This may cause floating-point results to change in some cases, and
2005 usually for the better, but may also cause numerically unstable
2006 algorithms to break.
2007
Tim Peters2f228e72001-05-13 00:19:31 +00002008- The implementation of dicts suffers fewer collisions, which has speed
2009 benefits. However, the order in which dict entries appear in dict.keys(),
2010 dict.values() and dict.items() may differ from previous releases for a
2011 given dict. Nothing is defined about this order, so no program should
2012 rely on it. Nevertheless, it's easy to write test cases that rely on the
2013 order by accident, typically because of printing the str() or repr() of a
2014 dict to an "expected results" file. See Lib/test/test_support.py's new
2015 sortdict(dict) function for a simple way to display a dict in sorted
2016 order.
2017
Tim Peters7a3bfc32001-06-12 01:22:22 +00002018- Many other small changes to dicts were made, resulting in faster
2019 operation along the most common code paths.
2020
Guido van Rossum10315822001-05-01 20:54:30 +00002021- Dictionary objects now support the "in" operator: "x in dict" means
2022 the same as dict.has_key(x).
2023
Barry Warsaw51acc8d2001-06-26 20:12:50 +00002024- The update() method of dictionaries now accepts generic mapping
2025 objects. Specifically the argument object must support the .keys()
2026 and __getitem__() methods. This allows you to say, for example,
2027 {}.update(UserDict())
2028
Guido van Rossum10315822001-05-01 20:54:30 +00002029- Iterators were added; this is a generalized way of providing values
2030 to a for loop. See PEP 234. There's a new built-in function iter()
2031 to return an iterator. There's a new protocol to get the next value
2032 from an iterator using the next() method (in Python) or the
2033 tp_iternext slot (in C). There's a new protocol to get iterators
2034 using the __iter__() method (in Python) or the tp_iter slot (in C).
2035 Iterating (i.e. a for loop) over a dictionary generates its keys.
2036 Iterating over a file generates its lines.
2037
Tim Petersf553f892001-05-01 20:45:31 +00002038- The following functions were generalized to work nicely with iterator
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002039 arguments: ::
2040
Tim Peterse63415e2001-05-08 04:38:29 +00002041 map(), filter(), reduce(), zip()
Tim Peters8572b4f2001-05-06 01:05:02 +00002042 list(), tuple() (PySequence_Tuple() and PySequence_Fast() in C API)
2043 max(), min()
Tim Peters1af03e92001-05-26 19:37:54 +00002044 join() method of strings
2045 extend() method of lists
Tim Peters75f8e352001-05-05 11:33:43 +00002046 'x in y' and 'x not in y' (PySequence_Contains() in C API)
2047 operator.countOf() (PySequence_Count() in C API)
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002048 right-hand side of assignment statements with multiple targets, such as ::
Tim Petersd6d010b2001-06-21 02:49:55 +00002049 x, y, z = some_iterable_object_returning_exactly_3_values
Tim Peters75f8e352001-05-05 11:33:43 +00002050
Tim Petersd85e1022001-05-11 21:51:48 +00002051- Accessing module attributes is significantly faster (for example,
2052 random.random or os.path or yourPythonModule.yourAttribute).
2053
Tim Peterse63415e2001-05-08 04:38:29 +00002054- Comparing dictionary objects via == and != is faster, and now works even
2055 if the keys and values don't support comparisons other than ==.
2056
Tim Peters95bf9392001-05-10 08:32:44 +00002057- Comparing dictionaries in ways other than == and != is slower: there were
2058 insecurities in the dict comparison implementation that could cause Python
2059 to crash if the element comparison routines for the dict keys and/or
2060 values mutated the dicts. Making the code bulletproof slowed it down.
2061
Tim Peterseb28ef22001-06-02 05:27:19 +00002062- Collisions in dicts are resolved via a new approach, which can help
2063 dramatically in bad cases. For example, looking up every key in a dict
Tim Peters7a3bfc32001-06-12 01:22:22 +00002064 d with d.keys() == [i << 16 for i in range(20000)] is approximately 500x
Tim Peterseb28ef22001-06-02 05:27:19 +00002065 faster now. Thanks to Christian Tismer for pointing out the cause and
2066 the nature of an effective cure (last December! better late than never).
Tim Peters15d49292001-05-27 07:39:22 +00002067
Tim Peters52e155e2001-06-16 05:42:57 +00002068- repr() is much faster for large containers (dict, list, tuple).
2069
2070
Tim Petersa814db52001-05-14 07:05:58 +00002071Library
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002072-------
Tim Petersa814db52001-05-14 07:05:58 +00002073
Fred Drake960fdf92001-07-20 18:38:26 +00002074- The constants ascii_letters, ascii_lowercase. and ascii_uppercase
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002075 were added to the string module. These a locale-independent
Fred Drake960fdf92001-07-20 18:38:26 +00002076 constants, unlike letters, lowercase, and uppercase. These are now
2077 use in appropriate locations in the standard library.
2078
Martin v. Löwisf0473d52001-07-18 16:17:16 +00002079- The flags used in dlopen calls can now be configured using
2080 sys.setdlopenflags and queried using sys.getdlopenflags.
2081
Guido van Rossumc7e4aca2001-07-12 11:54:37 +00002082- Fredrik Lundh's xmlrpclib is now a standard library module. This
2083 provides full client-side XML-RPC support. In addition,
2084 Demo/xmlrpc/ contains two server frameworks (one SocketServer-based,
2085 one asyncore-based). Thanks to Eric Raymond for the documentation.
2086
Guido van Rossum643d3912001-07-05 14:46:25 +00002087- The xrange() object is simplified: it no longer supports slicing,
2088 repetition, comparisons, efficient 'in' checking, the tolist()
2089 method, or the start, stop and step attributes. See PEP 260.
2090
Martin v. Löwisebf94db2001-06-06 06:25:40 +00002091- A new function fnmatch.filter to filter lists of file names was added.
2092
Barry Warsawffd674d2001-05-22 16:00:10 +00002093- calendar.py uses month and day names based on the current locale.
2094
Guido van Rossum2e0a6542001-05-15 02:14:44 +00002095- strop is now *really* obsolete (this was announced before with 1.6),
2096 and issues DeprecationWarning when used (except for the four items
2097 that are still imported into string.py).
2098
Tim Petersa814db52001-05-14 07:05:58 +00002099- Cookie.py now sorts key+value pairs by key in output strings.
2100
2101- pprint.isrecursive(object) didn't correctly identify recursive objects.
2102 Now it does.
2103
Tim Peters95b3f782001-05-14 18:39:41 +00002104- pprint functions now much faster for large containers (tuple, list, dict).
2105
Tim Peters7b9542a2001-06-10 23:40:19 +00002106- New 'q' and 'Q' format codes in the struct module, corresponding to C
2107 types "long long" and "unsigned long long" (on Windows, __int64). In
2108 native mode, these can be used only when the platform C compiler supports
2109 these types (when HAVE_LONG_LONG is #define'd by the Python config
2110 process), and then they inherit the sizes and alignments of the C types.
Tim Peters7a3bfc32001-06-12 01:22:22 +00002111 In standard mode, 'q' and 'Q' are supported on all platforms, and are
2112 8-byte integral types.
Tim Peters7b9542a2001-06-10 23:40:19 +00002113
Guido van Rossum83213cc2001-06-12 16:48:52 +00002114- The site module installs a new built-in function 'help' that invokes
2115 pydoc.help. It must be invoked as 'help()'; when invoked as 'help',
2116 it displays a message reminding the user to use 'help()' or
2117 'help(object)'.
2118
Tim Petersa814db52001-05-14 07:05:58 +00002119Tests
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002120-----
Tim Petersa814db52001-05-14 07:05:58 +00002121
2122- New test_mutants.py runs dict comparisons where the key and value
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002123 comparison operators mutate the dicts randomly during comparison. This
Tim Petersa814db52001-05-14 07:05:58 +00002124 rapidly causes Python to crash under earlier releases (not for the faint
2125 of heart: it can also cause Win9x to freeze or reboot!).
2126
Raymond Hettingerf2f2a2c2002-08-19 14:25:03 +00002127- New test_pprint.py verifies that pprint.isrecursive() and
Tim Peters95b3f782001-05-14 18:39:41 +00002128 pprint.isreadable() return sensible results. Also verifies that simple
2129 cases produce correct output.
Tim Petersa814db52001-05-14 07:05:58 +00002130
Tim Peters4324aa32001-05-28 22:30:08 +00002131C API
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002132-----
Tim Peters4324aa32001-05-28 22:30:08 +00002133
2134- Removed the unused last_is_sticky argument from the internal
2135 _PyTuple_Resize(). If this affects you, you were cheating.
Skip Montanaroe5d7f7f2002-09-20 14:16:59 +00002136
2137----
2138
2139**(For information about older versions, consult the HISTORY file.)**