blob: dce67806864380a1e97570e8df602cc3f612e04d [file] [log] [blame]
Tim Petersd66595f2001-02-04 03:09:53 +00001What's New in Python 2.1 alpha 507?
2===================================
3
4Core language, builtins, and interpreter
5
6Standard library
7
Martin v. Löwis2a5130e2001-02-27 04:21:58 +00008- pyexpat now detects the expat version if expat.h defines it. A
9 number of additional handlers are provided, which are only available
10 since expat 1.95. In addition, the methods SetParamEntityParsing and
11 GetInputContext of Parser objects are available with 1.95.x
12 only. Parser objects now provide the ordered_attributes and
13 specified_attributes attributes. A new module expat.model was added,
14 which offers a number of additional constants if 1.95.x is used.
15
16- xml.dom offers the new functions registerDOMImplementation and
17 getDOMImplementation.
18
19- xml.dom.minidom offers a toprettyxml method. A number of DOM
20 conformance issues have been resolved. In particular, Element now
21 has an hasAttributes method, and the handling of namespaces was
22 improved.
23
Tim Petersd66595f2001-02-04 03:09:53 +000024Windows changes
25
26- Build: Subproject _test (effectively) renamed to _testcapi.
27
Tim Peters25a9ce32001-02-19 07:06:36 +000028- winsound module: Under Win9x, winsound.Beep() now attempts to simulate
29 what it's supposed to do (and does do under NT and 2000) via direct
30 port manipulation. It's unknown whether this will work on all systems,
31 but it does work on my Win98SE system now and was known to be useless on
32 all Win9x systems before.
33
34
Tim Petersd7b5e882001-01-25 03:36:26 +000035What's New in Python 2.1 alpha 2?
36=================================
Tim Peters40ead762001-01-27 05:35:26 +000037
Tim Petersd7b5e882001-01-25 03:36:26 +000038Core language, builtins, and interpreter
39
Jeremy Hylton4589bd82001-02-01 20:38:45 +000040- Scopes nest. If a name is used in a function or class, but is not
41 local, the definition in the nearest enclosing function scope will
42 be used. One consequence of this change is that lambda statements
43 could reference variables in the namespaces where the lambda is
44 defined. In some unusual cases, this change will break code.
45
46 In all previous version of Python, names were resolved in exactly
47 three namespaces -- the local namespace, the global namespace, and
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +000048 the builtin namespace. According to this old definition, if a
Jeremy Hylton4589bd82001-02-01 20:38:45 +000049 function A is defined within a function B, the names bound in B are
50 not visible in A. The new rules make names bound in B visible in A,
51 unless A contains a name binding that hides the binding in B.
52
53 Section 4.1 of the reference manual describes the new scoping rules
54 in detail. The test script in Lib/test/test_scope.py demonstrates
55 some of the effects of the change.
56
57 The new rules will cause existing code to break if it defines nested
58 functions where an outer function has local variables with the same
59 name as globals or builtins used by the inner function. Example:
60
61 def munge(str):
62 def helper(x):
63 return str(x)
64 if type(str) != type(''):
65 str = helper(str)
66 return str.strip()
67
68 Under the old rules, the name str in helper() is bound to the
69 builtin function str(). Under the new rules, it will be bound to
70 the argument named str and an error will occur when helper() is
71 called.
72
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +000073- The compiler will report a SyntaxError if "from ... import *" occurs
74 in a function or class scope. The language reference has documented
75 that this case is illegal, but the compiler never checked for it.
76 The recent introduction of nested scope makes the meaning of this
77 form of name binding ambiguous. In a future release, the compiler
78 may allow this form when there is no possibility of ambiguity.
79
Tim Peters40ead762001-01-27 05:35:26 +000080- repr(string) is easier to read, now using hex escapes instead of octal,
81 and using \t, \n and \r instead of \011, \012 and \015 (respectively):
82
83 >>> "\texample \r\n" + chr(0) + chr(255)
84 '\texample \r\n\x00\xff' # in 2.1
85 '\011example \015\012\000\377' # in 2.0
86
Moshe Zadka6af0ce02001-01-29 06:41:00 +000087- Functions are now compared and hashed by identity, not by value, since
88 the func_code attribute is writable.
89
Fred Drakefb9d7122001-02-01 20:00:40 +000090- Weak references (PEP 205) have been added. This involves a few
91 changes in the core, an extension module (_weakref), and a Python
92 module (weakref). The weakref module is the public interface. It
93 includes support for "explicit" weak references, proxy objects, and
94 mappings with weakly held values.
95
Jeremy Hylton0072d5a2001-02-01 22:53:15 +000096- A 'continue' statement can now appear in a try block within the body
97 of a loop. It is still not possible to use continue in a finally
Tim Peters9ea17ac2001-02-02 05:57:15 +000098 clause.
Jeremy Hylton0072d5a2001-02-01 22:53:15 +000099
Tim Petersd7b5e882001-01-25 03:36:26 +0000100Standard library
101
Barry Warsaw30dbd142001-01-31 22:14:01 +0000102- mailbox.py now has a new class, PortableUnixMailbox which is
103 identical to UnixMailbox but uses a more portable scheme for
104 determining From_ separators. Also, the constructors for all the
105 classes in this module have a new optional `factory' argument, which
106 is a callable used when new message classes must be instantiated by
107 the next() method.
108
Tim Petersd7b5e882001-01-25 03:36:26 +0000109- random.py is now self-contained, and offers all the functionality of
110 the now-deprecated whrandom.py. See the docs for details. random.py
111 also supports new functions getstate() and setstate(), for saving
Tim Petersd52269b2001-01-25 06:23:18 +0000112 and restoring the internal state of the generator; and jumpahead(n),
113 for quickly forcing the internal state to be the same as if n calls to
114 random() had been made. The latter is particularly useful for multi-
115 threaded programs, creating one instance of the random.Random() class for
116 each thread, then using .jumpahead() to force each instance to use a
117 non-overlapping segment of the full period.
Tim Petersd7b5e882001-01-25 03:36:26 +0000118
Tim Peters0de88fc2001-02-01 04:59:18 +0000119- random.py's seed() function is new. For bit-for-bit compatibility with
120 prior releases, use the whseed function instead. The new seed function
121 addresses two problems: (1) The old function couldn't produce more than
122 about 2**24 distinct internal states; the new one about 2**45 (the best
123 that can be done in the Wichmann-Hill generator). (2) The old function
124 sometimes produced identical internal states when passed distinct
125 integers, and there was no simple way to predict when that would happen;
126 the new one guarantees to produce distinct internal states for all
127 arguments in [0, 27814431486576L).
128
Jeremy Hylton4c4fda02001-02-02 03:29:24 +0000129- The socket module now supports raw packets on Linux. The socket
130 family is AF_PACKET.
131
Tim Peters9ea17ac2001-02-02 05:57:15 +0000132- test_capi.py is a start at running tests of the Python C API. The tests
133 are implemented by the new Modules/_testmodule.c.
134
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000135- A new extension module, _symtable, provides provisional access to the
136 internal symbol table used by the Python compiler. A higher-level
137 interface will be added on top of _symtable in a future release.
138
Andrew M. Kuchlingdebc3522001-02-22 15:53:21 +0000139- Removed the obsolete soundex module.
140
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000141- xml.dom.minidom now uses the standard DOM exceptions. Node supports
142 the isSameNode method; NamedNodeMap the get method.
143
144- xml.sax.expatreader supports the lexical handler property; it
145 generates comment, startCDATA, and endCDATA events.
146
Tim Petersee826f82001-01-31 19:39:44 +0000147Windows changes
148
149- Build procedure: the zlib project is built in a different way that
150 ensures the zlib header files used can no longer get out of synch with
Tim Peters9ea17ac2001-02-02 05:57:15 +0000151 the zlib binary used. See PCbuild\readme.txt for details. Your old
152 zlib-related directories can be deleted; you'll need to download fresh
153 source for zlib and unpack it into a new directory.
Tim Petersee826f82001-01-31 19:39:44 +0000154
Tim Peters9ea17ac2001-02-02 05:57:15 +0000155- Build: New subproject _test for the benefit of test_capi.py (see above).
156
Tim Petersb16c56f2001-02-02 21:24:51 +0000157- Build: New subproject _symtable, for new DLL _symtable.pyd (a nascent
158 interface to some Python compiler internals).
159
160- Build: Subproject ucnhash is gone, since the code was folded into the
Tim Peters9ea17ac2001-02-02 05:57:15 +0000161 unicodedata subproject.
Tim Petersd7b5e882001-01-25 03:36:26 +0000162
Tim Petersa3a3a032000-11-30 05:22:44 +0000163What's New in Python 2.1 alpha 1?
164=================================
165
166Core language, builtins, and interpreter
167
Marc-André Lemburgebb195b2001-01-20 10:34:52 +0000168- There is a new Unicode companion to the PyObject_Str() API
169 called PyObject_Unicode(). It behaves in the same way as the
170 former, but assures that the returned value is an Unicode object
171 (applying the usual coercion if necessary).
Marc-André Lemburgad7c98e2001-01-17 17:09:53 +0000172
Guido van Rossumf98eda02001-01-17 15:54:45 +0000173- The comparison operators support "rich comparison overloading" (PEP
174 207). C extension types can provide a rich comparison function in
175 the new tp_richcompare slot in the type object. The cmp() function
176 and the C function PyObject_Compare() first try the new rich
177 comparison operators before trying the old 3-way comparison. There
178 is also a new C API PyObject_RichCompare() (which also falls back on
179 the old 3-way comparison, but does not constrain the outcome of the
180 rich comparison to a Boolean result).
181
182 The rich comparison function takes two objects (at least one of
183 which is guaranteed to have the type that provided the function) and
184 an integer indicating the opcode, which can be Py_LT, Py_LE, Py_EQ,
185 Py_NE, Py_GT, Py_GE (for <, <=, ==, !=, >, >=), and returns a Python
186 object, which may be NotImplemented (in which case the tp_compare
187 slot function is used as a fallback, if defined).
188
189 Classes can overload individual comparison operators by defining one
190 or more of the methods__lt__, __le__, __eq__, __ne__, __gt__,
Guido van Rossuma88479f2001-01-18 14:28:08 +0000191 __ge__. There are no explicit "reflected argument" versions of
192 these; instead, __lt__ and __gt__ are each other's reflection,
193 likewise for__le__ and __ge__; __eq__ and __ne__ are their own
194 reflection (similar at the C level). No other implications are
195 made; in particular, Python does not assume that == is the Boolean
196 inverse of !=, or that < is the Boolean inverse of >=. This makes
197 it possible to define types with partial orderings.
Guido van Rossumf98eda02001-01-17 15:54:45 +0000198
199 Classes or types that want to implement (in)equality tests but not
200 the ordering operators (i.e. unordered types) should implement ==
201 and !=, and raise an error for the ordering operators.
202
Guido van Rossuma88479f2001-01-18 14:28:08 +0000203 It is possible to define types whose rich comparison results are not
Guido van Rossumf98eda02001-01-17 15:54:45 +0000204 Boolean; e.g. a matrix type might want to return a matrix of bits
205 for A < B, giving elementwise comparisons. Such types should ensure
206 that any interpretation of their value in a Boolean context raises
207 an exception, e.g. by defining __nonzero__ (or the tp_nonzero slot
208 at the C level) to always raise an exception.
209
Guido van Rossuma88479f2001-01-18 14:28:08 +0000210- Complex numbers use rich comparisons to define == and != but raise
211 an exception for <, <=, > and >=. Unfortunately, this also means
212 that cmp() of two complex numbers raises an exception when the two
213 numbers differ. Since it is not mathematically meaningful to compare
214 complex numbers except for equality, I hope that this doesn't break
215 too much code.
216
Tim Peters3389f192001-02-18 08:48:49 +0000217- The outcome of comparing non-numeric objects of different types is
Tim Peters14495852001-02-18 08:28:33 +0000218 not defined by the language, other than that it's arbitrary but
219 consistent (see the Reference Manual). An implementation detail changed
220 in 2.1a1 such that None now compares less than any other object. Code
221 relying on this new behavior (like code that relied on the previous
222 behavior) does so at its own risk.
223
Barry Warsaw573b5412001-01-15 20:43:18 +0000224- Functions and methods now support getting and setting arbitrarily
225 named attributes (PEP 232). Functions have a new __dict__
226 (a.k.a. func_dict) which hold the function attributes. Methods get
227 and set attributes on their underlying im_func. It is a TypeError
228 to set an attribute on a bound method.
229
Guido van Rossum051e3352001-01-15 19:11:10 +0000230- The xrange() object implementation has been improved so that
231 xrange(sys.maxint) can be used on 64-bit platforms. There's still a
232 limitation that in this case len(xrange(sys.maxint)) can't be
233 calculated, but the common idiom "for i in xrange(sys.maxint)" will
234 work fine as long as the index i doesn't actually reach 2**31.
235 (Python uses regular ints for sequence and string indices; fixing
236 that is much more work.)
237
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000238- Two changes to from...import:
239
Guido van Rossumba381232001-02-03 15:06:40 +0000240 1) "from M import X" now works even if (after loading module M)
241 sys.modules['M'] is not a real module; it's basically a getattr()
242 operation with AttributeError exceptions changed into ImportError.
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000243
244 2) "from M import *" now looks for M.__all__ to decide which names to
245 import; if M.__all__ doesn't exist, it uses M.__dict__.keys() but
246 filters out names starting with '_' as before. Whether or not
247 __all__ exists, there's no restriction on the type of M.
248
Guido van Rossumf61f1662001-01-10 20:13:55 +0000249- File objects have a new method, xreadlines(). This is the fastest
250 way to iterate over all lines in a file:
251
252 for line in file.xreadlines():
253 ...do something to line...
254
255 See the xreadlines module (mentioned below) for how to do this for
256 other file-like objects.
257
258- Even if you don't use file.xreadlines(), you may expect a speedup on
259 line-by-line input. The file.readline() method has been optimized
Tim Petersf29b64d2001-01-15 06:33:19 +0000260 quite a bit in platform-specific ways: on systems (like Linux) that
261 support flockfile(), getc_unlocked(), and funlockfile(), those are
262 used by default. On systems (like Windows) without getc_unlocked(),
263 a complicated (but still thread-safe) method using fgets() is used by
264 default.
265
Tim Petersd52269b2001-01-25 06:23:18 +0000266 You can force use of the fgets() method by #define'ing
267 USE_FGETS_IN_GETLINE at build time (it may be faster than
Tim Petersf29b64d2001-01-15 06:33:19 +0000268 getc_unlocked()).
269
Tim Petersd52269b2001-01-25 06:23:18 +0000270 You can force fgets() not to be used by #define'ing
271 DONT_USE_FGETS_IN_GETLINE (this is the first thing to try if std test
Tim Petersf29b64d2001-01-15 06:33:19 +0000272 test_bufio.py fails -- and let us know if it does!).
273
274- In addition, the fileinput module, while still slower than the other
275 methods on most platforms, has been sped up too, by using
276 file.readlines(sizehint).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000277
278- Support for run-time warnings has been added, including a new
279 command line option (-W) to specify the disposition of warnings.
280 See the description of the warnings module below.
281
282- Extensive changes have been made to the coercion code. This mostly
283 affects extension modules (which can now implement mixed-type
284 numerical operators without having to use coercion), but
285 occasionally, in boundary cases the coercion semantics have changed
286 subtly. Since this was a terrible gray area of the language, this
Guido van Rossumae72d872001-01-11 15:00:14 +0000287 is considered an improvement. Also note that __rcmp__ is no longer
Guido van Rossumf61f1662001-01-10 20:13:55 +0000288 supported -- instead of calling __rcmp__, __cmp__ is called with
Guido van Rossuma88479f2001-01-18 14:28:08 +0000289 reflected arguments.
Guido van Rossumf61f1662001-01-10 20:13:55 +0000290
Guido van Rossumf98eda02001-01-17 15:54:45 +0000291- In connection with the coercion changes, a new built-in singleton
292 object, NotImplemented is defined. This can be returned for
293 operations that wish to indicate they are not implemented for a
294 particular combination of arguments. From C, this is
295 Py_NotImplemented.
296
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000297- The interpreter accepts now bytecode files on the command line even
298 if they do not have a .pyc or .pyo extension. On Linux, after executing
299
Martin v. Löwise214baa2001-02-04 22:37:56 +0000300import imp,sys,string
301magic = string.join(["\\x%.2x" % ord(c) for c in imp.get_magic()],"")
302reg = ':pyc:M::%s::%s:' % (magic, sys.executable)
303open("/proc/sys/fs/binfmt_misc/register","wb").write(reg)
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000304
305 any byte code file can be used as an executable (i.e. as an argument
306 to execve(2)).
307
Tim Peters9940b802000-12-01 07:59:35 +0000308- %[xXo] formats of negative Python longs now produce a sign
Tim Petersa3a3a032000-11-30 05:22:44 +0000309 character. In 1.6 and earlier, they never produced a sign,
310 and raised an error if the value of the long was too large
311 to fit in a Python int. In 2.0, they produced a sign if and
312 only if too large to fit in an int. This was inconsistent
313 across platforms (because the size of an int varies across
314 platforms), and inconsistent with hex() and oct(). Example:
315
316 >>> "%x" % -0x42L
Tim Peters9940b802000-12-01 07:59:35 +0000317 '-42' # in 2.1
Tim Petersa3a3a032000-11-30 05:22:44 +0000318 'ffffffbe' # in 2.0 and before, on 32-bit machines
319 >>> hex(-0x42L)
320 '-0x42L' # in all versions of Python
321
Tim Peters9940b802000-12-01 07:59:35 +0000322 The behavior of %d formats for negative Python longs remains
323 the same as in 2.0 (although in 1.6 and before, they raised
324 an error if the long didn't fit in a Python int).
325
326 %u formats don't make sense for Python longs, but are allowed
327 and treated the same as %d in 2.1. In 2.0, a negative long
328 formatted via %u produced a sign if and only if too large to
329 fit in an int. In 1.6 and earlier, a negative long formatted
330 via %u raised an error if it was too big to fit in an int.
331
Guido van Rossum3661d392000-12-12 22:10:31 +0000332- Dictionary objects have an odd new method, popitem(). This removes
333 an arbitrary item from the dictionary and returns it (in the form of
334 a (key, value) pair). This can be useful for algorithms that use a
335 dictionary as a bag of "to do" items and repeatedly need to pick one
336 item. Such algorithms normally end up running in quadratic time;
337 using popitem() they can usually be made to run in linear time.
338
Tim Peters36cdad12000-12-29 02:06:45 +0000339Standard library
340
Thomas Woutersfe385252001-01-19 23:16:56 +0000341- In the time module, the time argument to the functions strftime,
342 localtime, gmtime, asctime and ctime is now optional, defaulting to
343 the current time (in the local timezone).
344
Guido van Rossumda91f222001-01-15 16:36:08 +0000345- The ftplib module now defaults to passive mode, which is deemed a
346 more useful default given that clients are often inside firewalls
347 these days. Note that this could break if ftplib is used to connect
348 to a *server* that is inside a firewall, from outside; this is
349 expected to be a very rare situation. To fix that, you can call
350 ftp.set_pasv(0).
351
Martin v. Löwis10a27872001-01-13 09:54:41 +0000352- The module site now treats .pth files not only for path configuration,
353 but also supports extensions to the initialization code: Lines starting
354 with import are executed.
355
Guido van Rossumf61f1662001-01-10 20:13:55 +0000356- There's a new module, warnings, which implements a mechanism for
357 issuing and filtering warnings. There are some new built-in
358 exceptions that serve as warning categories, and a new command line
359 option, -W, to control warnings (e.g. -Wi ignores all warnings, -We
360 turns warnings into errors). warnings.warn(message[, category])
361 issues a warning message; this can also be called from C as
362 PyErr_Warn(category, message).
363
364- A new module xreadlines was added. This exports a single factory
365 function, xreadlines(). The intention is that this code is the
366 absolutely fastest way to iterate over all lines in an open
367 file(-like) object:
368
369 import xreadlines
370 for line in xreadlines.xreadlines(file):
371 ...do something to line...
372
373 This is equivalent to the previous the speed record holder using
374 file.readlines(sizehint). Note that if file is a real file object
375 (as opposed to a file-like object), this is equivalent:
376
377 for line in file.xreadlines():
378 ...do something to line...
379
Tim Peters36cdad12000-12-29 02:06:45 +0000380- The bisect module has new functions bisect_left, insort_left,
381 bisect_right and insort_right. The old names bisect and insort
382 are now aliases for bisect_right and insort_right. XXX_right
383 and XXX_left methods differ in what happens when the new element
384 compares equal to one or more elements already in the list: the
385 XXX_left methods insert to the left, the XXX_right methods to the
Tim Peters742bb6f2001-01-05 08:05:32 +0000386 right. Code that doesn't care where equal elements end up should
387 continue to use the old, short names ("bisect" and "insort").
Tim Peters36cdad12000-12-29 02:06:45 +0000388
Andrew M. Kuchlingf6f3a892001-01-13 14:53:34 +0000389- The new curses.panel module wraps the panel library that forms part
390 of SYSV curses and ncurses. Contributed by Thomas Gellekum.
391
Guido van Rossumf61f1662001-01-10 20:13:55 +0000392- The SocketServer module now sets the allow_reuse_address flag by
393 default in the TCPServer class.
394
395- A new function, sys._getframe(), returns the stack frame pointer of
396 the caller. This is intended only as a building block for
397 higher-level mechanisms such as string interpolation.
398
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000399- The pyexpat module supports a number of new handlers, which are
400 available only in expat 1.2. If invocation of a callback fails, it
401 will report an additional frame in the traceback. Parser objects
402 participate now in garbage collection. If expat reports an unknown
403 encoding, pyexpat will try to use a Python codec; that works only
404 for single-byte charsets. The parser type objects is exposed as
405 XMLParserObject.
406
407- xml.dom now offers standard definitions for symbolic node type and
408 exception code constants, and a hierarchy of DOM exceptions. minidom
409 was adjusted to use them.
410
411- The conformance of xml.dom.minidom to the DOM specification was
412 improved. It detects a number of additional error cases; the
413 previous/next relationship works even when the tree is modified;
414 Node supports the normalize() method; NamedNodeMap, DocumentType and
415 DOMImplementation classes were added; Element supports the
416 hasAttribute and hasAttributeNS methods; and Text supports the splitText
417 method.
418
Guido van Rossumf61f1662001-01-10 20:13:55 +0000419Build issues
420
Guido van Rossum1e33bdc2001-01-23 03:17:00 +0000421- For Unix (and Unix-compatible) builds, configuration and building of
422 extension modules is now greatly automated. Rather than having to
423 edit the Modules/Setup file to indicate which modules should be
424 built and where their include files and libraries are, a
425 distutils-based setup.py script now takes care of building most
426 extension modules. All extension modules built this way are built
427 as shared libraries. Only a few modules that must be linked
428 statically are still listed in the Setup file; you won't need to
429 edit their configuration.
430
431- Python should now build out of the box on Cygwin. If it doesn't,
432 mail to Jason Tishler (jlt63 at users.sourceforge.net).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000433
434- Python now always uses its own (renamed) implementation of getopt()
435 -- there's too much variation among C library getopt()
436 implementations.
437
438- C++ compilers are better supported; the CXX macro is always set to a
439 C++ compiler if one is found.
Tim Peters36cdad12000-12-29 02:06:45 +0000440
Tim Petersd92dfe02000-12-12 01:18:41 +0000441Windows changes
442
443- select module: By default under Windows, a select() call
444 can specify no more than 64 sockets. Python now boosts
445 this Microsoft default to 512. If you need even more than
446 that, see the MS docs (you'll need to #define FD_SETSIZE
447 and recompile Python from source).
448
Guido van Rossumf61f1662001-01-10 20:13:55 +0000449- Support for Windows 3.1, DOS and OS/2 is gone. The Lib/dos-8x3
450 subdirectory is no more!
451
Tim Petersa3a3a032000-11-30 05:22:44 +0000452
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000453What's New in Python 2.0?
Fred Drake1a640502000-10-16 20:27:25 +0000454=========================
Guido van Rossum61000331997-08-15 04:39:58 +0000455
Guido van Rossum8ed602b2000-09-01 22:34:33 +0000456Below is a list of all relevant changes since release 1.6. Older
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000457changes are in the file HISTORY. If you are making the jump directly
458from Python 1.5.2 to 2.0, make sure to read the section for 1.6 in the
459HISTORY file! Many important changes listed there.
Guido van Rossum61000331997-08-15 04:39:58 +0000460
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000461Alternatively, a good overview of the changes between 1.5.2 and 2.0 is
462the document "What's New in Python 2.0" by Kuchling and Moshe Zadka:
463http://starship.python.net/crew/amk/python/writing/new-python/.
Guido van Rossum1f83cce1997-10-06 21:04:35 +0000464
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000465--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)
Guido van Rossum437cfe81999-04-08 20:17:57 +0000466
467======================================================================
468
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000469What's new in 2.0 (since release candidate 1)?
470==============================================
471
472Standard library
473
474- The copy_reg module was modified to clarify its intended use: to
475 register pickle support for extension types, not for classes.
476 pickle() will raise a TypeError if it is passed a class.
477
478- Fixed a bug in gettext's "normalize and expand" code that prevented
479 it from finding an existing .mo file.
480
481- Restored support for HTTP/0.9 servers in httplib.
482
Tim Peters989b7b92000-10-16 20:24:53 +0000483- The math module was changed to stop raising OverflowError in case of
484 underflow, and return 0 instead in underflow cases. Whether Python
485 used to raise OverflowError in case of underflow was platform-
486 dependent (it did when the platform math library set errno to ERANGE
487 on underflow).
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000488
489- Fixed a bug in StringIO that occurred when the file position was not
490 at the end of the file and write() was called with enough data to
491 extend past the end of the file.
492
493- Fixed a bug that caused Tkinter error messages to get lost on
494 Windows. The bug was fixed by replacing direct use of
495 interp->result with Tcl_GetStringResult(interp).
496
497- Fixed bug in urllib2 that caused it to fail when it received an HTTP
498 redirect response.
499
500- Several changes were made to distutils: Some debugging code was
501 removed from util. Fixed the installer used when an external zip
502 program (like WinZip) is not found; the source code for this
503 installer is in Misc/distutils. check_lib() was modified to behave
504 more like AC_CHECK_LIB by add other_libraries() as a parameter. The
505 test for whether installed modules are on sys.path was changed to
506 use both normcase() and normpath().
507
Jeremy Hyltond867a2c2000-10-16 20:41:38 +0000508- Several minor bugs were fixed in the xml package (the minidom,
509 pulldom, expatreader, and saxutils modules).
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000510
511- The regression test driver (regrtest.py) behavior when invoked with
512 -l changed: It now reports a count of objects that are recognized as
513 garbage but not freed by the garbage collector.
514
Tim Peters989b7b92000-10-16 20:24:53 +0000515- The regression test for the math module was changed to test
516 exceptional behavior when the test is run in verbose mode. Python
517 cannot yet guarantee consistent exception behavior across platforms,
518 so the exception part of test_math is run only in verbose mode, and
519 may fail on your platform.
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000520
521Internals
522
523- PyOS_CheckStack() has been disabled on Win64, where it caused
524 test_sre to fail.
525
526Build issues
527
528- Changed compiler flags, so that gcc is always invoked with -Wall and
529 -Wstrict-prototypes. Users compiling Python with GCC should see
530 exactly one warning, except if they have passed configure the
Tim Peters989b7b92000-10-16 20:24:53 +0000531 --with-pydebug flag. The expected warning is for getopt() in
Tim Petersadfb94f2000-10-16 20:51:33 +0000532 Modules/main.c. This warning will be fixed for Python 2.1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000533
Tim Petersa3a3a032000-11-30 05:22:44 +0000534- Fixed configure to add -threads argument during linking on OSF1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000535
536Tools and other miscellany
537
538- The compiler in Tools/compiler was updated to support the new
539 language features introduced in 2.0: extended print statement, list
540 comprehensions, and augmented assignments. The new compiler should
541 also be backwards compatible with Python 1.5.2; the compiler will
542 always generate code for the version of the interpreter it runs
Tim Petersa3a3a032000-11-30 05:22:44 +0000543 under.
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000544
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000545What's new in 2.0 release candidate 1 (since beta 2)?
546=====================================================
547
Jeremy Hylton6040aaa2000-10-09 21:27:22 +0000548What is release candidate 1?
549
550We believe that release candidate 1 will fix all known bugs that we
551intend to fix for the 2.0 final release. This release should be a bit
552more stable than the previous betas. We would like to see even more
553widespread testing before the final release, so we are producing this
554release candidate. The final release will be exactly the same unless
555any show-stopping (or brown bag) bugs are found by testers of the
556release candidate.
557
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000558All the changes since the last beta release are bug fixes or changes
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000559to support building Python for specific platforms.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000560
561Core language, builtins, and interpreter
562
563- A bug that caused crashes when __coerce__ was used with augmented
564 assignment, e.g. +=, was fixed.
565
566- Raise ZeroDivisionError when raising zero to a negative number,
567 e.g. 0.0 ** -2.0. Note that math.pow is unrelated to the builtin
568 power operator and the result of math.pow(0.0, -2.0) will vary by
569 platform. On Linux, it raises a ValueError.
570
571- A bug in Unicode string interpolation was fixed that occasionally
572 caused errors with formats including "%%". For example, the
573 following expression "%% %s" % u"abc" no longer raises a TypeError.
574
575- Compilation of deeply nested expressions raises MemoryError instead
576 of SyntaxError, e.g. eval("[" * 50 + "]" * 50).
577
578- In 2.0b2 on Windows, the interpreter wrote .pyc files in text mode,
579 rendering them useless. They are now written in binary mode again.
580
581Standard library
582
583- Keyword arguments are now accepted for most pattern and match object
584 methods in SRE, the standard regular expression engine.
585
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000586- In SRE, fixed error with negative lookahead and lookbehind that
Jeremy Hylton32e20ff2000-10-09 19:48:11 +0000587 manifested itself as a runtime error in patterns like "(?<!abc)(def)".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000588
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000589- Several bugs in the Unicode handling and error handling in _tkinter
590 were fixed.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000591
592- Fix memory management errors in Merge() and Tkapp_Call() routines.
593
594- Several changes were made to cStringIO to make it compatible with
595 the file-like object interface and with StringIO. If operations are
596 performed on a closed object, an exception is raised. The truncate
597 method now accepts a position argument and readline accepts a size
Tim Petersa3a3a032000-11-30 05:22:44 +0000598 argument.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000599
600- There were many changes made to the linuxaudiodev module and its
601 test suite; as a result, a short, unexpected audio sample should now
Tim Petersa3a3a032000-11-30 05:22:44 +0000602 play when the regression test is run.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000603
604 Note that this module is named poorly, because it should work
605 correctly on any platform that supports the Open Sound System
Tim Petersa3a3a032000-11-30 05:22:44 +0000606 (OSS).
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000607
608 The module now raises exceptions when errors occur instead of
609 crashing. It also defines the AFMT_A_LAW format (logarithmic A-law
610 audio) and defines a getptr() method that calls the
611 SNDCTL_DSP_GETxPTR ioctl defined in the OSS Programmer's Guide.
612
613- The library_version attribute, introduced in an earlier beta, was
614 removed because it can not be supported with early versions of the C
615 readline library, which provides no way to determine the version at
616 compile-time.
617
618- The binascii module is now enabled on Win64.
619
Tim Peters46446d62000-10-09 21:19:31 +0000620- tokenize.py no longer suffers "recursion depth" errors when parsing
621 programs with very long string literals.
622
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000623Internals
624
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000625- Fixed several buffer overflow vulnerabilities in calculate_path(),
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000626 which is called when the interpreter starts up to determine where
627 the standard library is installed. These vulnerabilities affect all
628 previous versions of Python and can be exploited by setting very
629 long values for PYTHONHOME or argv[0]. The risk is greatest for a
630 setuid Python script, although use of the wrapper in
631 Misc/setuid-prog.c will eliminate the vulnerability.
632
633- Fixed garbage collection bugs in instance creation that were
634 triggered when errors occurred during initialization. The solution,
635 applied in cPickle and in PyInstance_New(), is to call
636 PyObject_GC_Init() after the initialization of the object's
637 container attributes is complete.
638
639- pyexpat adds definitions of PyModule_AddStringConstant and
640 PyModule_AddObject if the Python version is less than 2.0, which
641 provides compatibility with PyXML on Python 1.5.2.
642
643- If the platform has a bogus definition for LONG_BIT (the number of
644 bits in a long), an error will be reported at compile time.
645
646- Fix bugs in _PyTuple_Resize() which caused hard-to-interpret garbage
647 collection crashes and possibly other, unreported crashes.
648
649- Fixed a memory leak in _PyUnicode_Fini().
650
651Build issues
652
653- configure now accepts a --with-suffix option that specifies the
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000654 executable suffix. This is useful for builds on Cygwin and Mac OS
Tim Petersa3a3a032000-11-30 05:22:44 +0000655 X, for example.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000656
657- The mmap.PAGESIZE constant is now initialized using sysconf when
658 possible, which eliminates a dependency on -lucb for Reliant UNIX.
659
660- The md5 file should now compile on all platforms.
661
662- The select module now compiles on platforms that do not define
663 POLLRDNORM and related constants.
664
665- Darwin (Mac OS X): Initial support for static builds on this
Tim Petersa3a3a032000-11-30 05:22:44 +0000666 platform.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000667
Jeremy Hylton10921202000-10-09 18:34:12 +0000668- BeOS: A number of changes were made to the build and installation
669 process. ar-fake now operates on a directory of object files.
670 dl_export.h is gone, and its macros now appear on the mwcc command
671 line during build on PPC BeOS.
672
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000673- Platform directory in lib/python2.0 is "plat-beos5" (or
Jeremy Hylton10921202000-10-09 18:34:12 +0000674 "plat-beos4", if building on BeOS 4.5), rather than "plat-beos".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000675
676- Cygwin: Support for shared libraries, Tkinter, and sockets.
677
678- SunOS 4.1.4_JL: Fix test for directory existence in configure.
679
680Tools and other miscellany
681
682- Removed debugging prints from main used with freeze.
683
Tim Peters46446d62000-10-09 21:19:31 +0000684- IDLE auto-indent no longer crashes when it encounters Unicode
685 characters.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000686
687What's new in 2.0 beta 2 (since beta 1)?
688========================================
689
690Core language, builtins, and interpreter
691
Tim Peters482c0212000-09-26 06:33:09 +0000692- Add support for unbounded ints in %d,i,u,x,X,o formats; for example
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000693 "%d" % 2L**64 == "18446744073709551616".
Jeremy Hylton1b618592000-09-26 05:32:36 +0000694
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000695- Add -h and -V command line options to print the usage message and
696 Python version number and exit immediately.
697
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000698- eval() and exec accept Unicode objects as code parameters.
699
700- getattr() and setattr() now also accept Unicode objects for the
701 attribute name, which are converted to strings using the default
702 encoding before lookup.
703
704- Multiplication on string and Unicode now does proper bounds
705 checking; e.g. 'a' * 65536 * 65536 will raise ValueError, "repeated
706 string is too long."
707
708- Better error message when continue is found in try statement in a
Tim Petersa3a3a032000-11-30 05:22:44 +0000709 loop.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000710
Jeremy Hylton1b618592000-09-26 05:32:36 +0000711
712Standard library and extensions
713
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000714- array: reverse() method of array now works. buffer_info() now does
Jeremy Hylton1b618592000-09-26 05:32:36 +0000715 argument checking; it still takes no arguments.
716
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000717- asyncore/asynchat: Included most recent version from Sam Rushing.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000718
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000719- cgi: Accept '&' or ';' as separator characters when parsing form data.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000720
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000721- CGIHTTPServer: Now works on Windows (and perhaps even Mac).
Jeremy Hylton1b618592000-09-26 05:32:36 +0000722
723- ConfigParser: When reading the file, options spelled in upper case
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000724 letters are now correctly converted to lowercase.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000725
726- copy: Copy Unicode objects atomically.
727
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000728- cPickle: Fail gracefully when copy_reg can't be imported.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000729
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000730- cStringIO: Implemented readlines() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000731
Fred Drake67233bc2000-09-26 16:40:27 +0000732- dbm: Add get() and setdefault() methods to dbm object. Add constant
733 `library' to module that names the library used. Added doc strings
734 and method names to error messages. Uses configure to determine
735 which ndbm.h file to include; Berkeley DB's nbdm and GDBM's ndbm is
736 now available options.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000737
738- distutils: Update to version 0.9.3.
739
740- dl: Add several dl.RTLD_ constants.
741
742- fpectl: Now supported on FreeBSD.
743
744- gc: Add DEBUG_SAVEALL option. When enabled all garbage objects
745 found by the collector will be saved in gc.garbage. This is useful
746 for debugging a program that creates reference cycles.
747
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000748- httplib: Three changes: Restore support for set_debuglevel feature
Jeremy Hylton1b618592000-09-26 05:32:36 +0000749 of HTTP class. Do not close socket on zero-length response. Do not
750 crash when server sends invalid content-length header.
751
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000752- mailbox: Mailbox class conforms better to qmail specifications.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000753
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000754- marshal: When reading a short, sign-extend on platforms where shorts
755 are bigger than 16 bits. When reading a long, repair the unportable
756 sign extension that was being done for 64-bit machines. (It assumed
757 that signed right shift sign-extends.)
758
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000759- operator: Add contains(), invert(), __invert__() as aliases for
760 __contains__(), inv(), and __inv__() respectively.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000761
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000762- os: Add support for popen2() and popen3() on all platforms where
763 fork() exists. (popen4() is still in the works.)
Jeremy Hylton1b618592000-09-26 05:32:36 +0000764
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000765- os: (Windows only:) Add startfile() function that acts like double-
Tim Peters482c0212000-09-26 06:33:09 +0000766 clicking on a file in Explorer (or passing the file name to the
767 DOS "start" command).
Jeremy Hylton1b618592000-09-26 05:32:36 +0000768
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000769- os.path: (Windows, DOS:) Treat trailing colon correctly in
Tim Peters482c0212000-09-26 06:33:09 +0000770 os.path.join. os.path.join("a:", "b") yields "a:b".
Jeremy Hylton1b618592000-09-26 05:32:36 +0000771
772- pickle: Now raises ValueError when an invalid pickle that contains
773 a non-string repr where a string repr was expected. This behavior
774 matches cPickle.
775
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000776- posixfile: Remove broken __del__() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000777
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000778- py_compile: support CR+LF line terminators in source file.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000779
780- readline: Does not immediately exit when ^C is hit when readline and
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000781 threads are configured. Adds definition of rl_library_version. (The
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000782 latter addition requires GNU readline 2.2 or later.)
Jeremy Hylton1b618592000-09-26 05:32:36 +0000783
784- rfc822: Domain literals returned by AddrlistClass method
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000785 getdomainliteral() are now properly wrapped in brackets.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000786
787- site: sys.setdefaultencoding() should only be called in case the
Tim Peters482c0212000-09-26 06:33:09 +0000788 standard default encoding ("ascii") is changed. This saves quite a
Jeremy Hylton1b618592000-09-26 05:32:36 +0000789 few cycles during startup since the first call to
790 setdefaultencoding() will initialize the codec registry and the
791 encodings package.
792
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000793- socket: Support for size hint in readlines() method of object returned
794 by makefile().
Jeremy Hylton1b618592000-09-26 05:32:36 +0000795
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000796- sre: Added experimental expand() method to match objects. Does not
Jeremy Hylton625915e2000-10-02 13:43:33 +0000797 use buffer interface on Unicode strings. Does not hang if group id
Jeremy Hylton1b618592000-09-26 05:32:36 +0000798 is followed by whitespace.
799
Tim Petersa3a3a032000-11-30 05:22:44 +0000800- StringIO: Size hint in readlines() is now supported as documented.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000801
802- struct: Check ranges for bytes and shorts.
803
804- urllib: Improved handling of win32 proxy settings. Fixed quote and
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000805 quote_plus functions so that the always encode a comma.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000806
807- Tkinter: Image objects are now guaranteed to have unique ids. Set
808 event.delta to zero if Tk version doesn't support mousewheel.
809 Removed some debugging prints.
810
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000811- UserList: now implements __contains__().
Jeremy Hylton1b618592000-09-26 05:32:36 +0000812
Fred Drake67233bc2000-09-26 16:40:27 +0000813- webbrowser: On Windows, use os.startfile() instead of os.popen(),
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000814 which works around a bug in Norton AntiVirus 2000 that leads directly
815 to a Blue Screen freeze.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000816
817- xml: New version detection code allows PyXML to override standard
818 XML package if PyXML version is greater than 0.6.1.
819
Fred Drake64bb3802000-09-26 16:21:35 +0000820- xml.dom: DOM level 1 support for basic XML. Includes xml.dom.minidom
821 (conventional DOM), and xml.dom.pulldom, which allows building the DOM
822 tree only for nodes which are sufficiently interesting to a specific
823 application. Does not provide the HTML-specific extensions. Still
824 undocumented.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000825
Fred Drake64bb3802000-09-26 16:21:35 +0000826- xml.sax: SAX 2 support for Python, including all the handler
827 interfaces needed to process XML 1.0 compliant XML. Some
828 documentation is already available.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000829
Fred Drake64bb3802000-09-26 16:21:35 +0000830- pyexpat: Renamed to xml.parsers.expat since this is part of the new,
831 packagized XML support.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000832
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000833
Jeremy Hylton1b618592000-09-26 05:32:36 +0000834C API
835
836- Add three new convenience functions for module initialization --
837 PyModule_AddObject(), PyModule_AddIntConstant(), and
838 PyModule_AddStringConstant().
839
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000840- Cleaned up definition of NULL in C source code; all definitions were
Jeremy Hylton1b618592000-09-26 05:32:36 +0000841 removed and add #error to Python.h if NULL isn't defined after
842 #include of stdio.h.
843
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000844- Py_PROTO() macros that were removed in 2.0b1 have been restored for
Jeremy Hylton1b618592000-09-26 05:32:36 +0000845 backwards compatibility (at the source level) with old extensions.
846
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000847- A wrapper API was added for signal() and sigaction(). Instead of
848 either function, always use PyOS_getsig() to get a signal handler
849 and PyOS_setsig() to set one. A new convenience typedef
850 PyOS_sighandler_t is defined for the type of signal handlers.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000851
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000852- Add PyString_AsStringAndSize() function that provides access to the
Jeremy Hylton1b618592000-09-26 05:32:36 +0000853 internal data buffer and size of a string object -- or the default
854 encoded version of a Unicode object.
855
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000856- PyString_Size() and PyString_AsString() accept Unicode objects.
857
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000858- The standard header <limits.h> is now included by Python.h (if it
Fred Drake64bb3802000-09-26 16:21:35 +0000859 exists). INT_MAX and LONG_MAX will always be defined, even if
860 <limits.h> is not available.
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000861
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000862- PyFloat_FromString takes a second argument, pend, that was
863 effectively useless. It is now officially useless but preserved for
864 backwards compatibility. If the pend argument is not NULL, *pend is
865 set to NULL.
866
867- PyObject_GetAttr() and PyObject_SetAttr() now accept Unicode objects
868 for the attribute name. See note on getattr() above.
869
870- A few bug fixes to argument processing for Unicode.
871 PyArg_ParseTupleAndKeywords() now accepts "es#" and "es".
872 PyArg_Parse() special cases "s#" for Unicode objects; it returns a
873 pointer to the default encoded string data instead of to the raw
Tim Petersa3a3a032000-11-30 05:22:44 +0000874 UTF-16.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000875
876- Py_BuildValue accepts B format (for bgen-generated code).
877
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000878
Jeremy Hylton1b618592000-09-26 05:32:36 +0000879Internals
880
881- On Unix, fix code for finding Python installation directory so that
882 it works when argv[0] is a relative path.
883
Andrew M. Kuchlinga1099be2000-12-15 01:16:43 +0000884- Added a true unicode_internal_encode() function and fixed the
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000885 unicode_internal_decode function() to support Unicode objects directly
Jeremy Hylton1b618592000-09-26 05:32:36 +0000886 rather than by generating a copy of the object.
887
Tim Peters482c0212000-09-26 06:33:09 +0000888- Several of the internal Unicode tables are much smaller now, and
889 the source code should be much friendlier to weaker compilers.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000890
Jeremy Hylton97693b02000-09-26 17:42:51 +0000891- In the garbage collector: Fixed bug in collection of tuples. Fixed
892 bug that caused some instances to be removed from the container set
893 while they were still live. Fixed parsing in gc.set_debug() for
894 platforms where sizeof(long) > sizeof(int).
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000895
896- Fixed refcount problem in instance deallocation that only occurred
897 when Py_REF_DEBUG was defined and Py_TRACE_REFS was not.
898
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000899- On Windows, getpythonregpath is now protected against null data in
900 registry key.
901
902- On Unix, create .pyc/.pyo files with O_EXCL flag to avoid a race
Tim Petersa3a3a032000-11-30 05:22:44 +0000903 condition.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000904
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000905
Jeremy Hylton1b618592000-09-26 05:32:36 +0000906Build and platform-specific issues
907
908- Better support of GNU Pth via --with-pth configure option.
909
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000910- Python/C API now properly exposed to dynamically-loaded extension
911 modules on Reliant UNIX.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000912
913- Changes for the benefit of SunOS 4.1.4 (really!). mmapmodule.c:
914 Don't define MS_SYNC to be zero when it is undefined. Added missing
915 prototypes in posixmodule.c.
916
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000917- Improved support for HP-UX build. Threads should now be correctly
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000918 configured (on HP-UX 10.20 and 11.00).
Jeremy Hylton1b618592000-09-26 05:32:36 +0000919
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000920- Fix largefile support on older NetBSD systems and OpenBSD by adding
921 define for TELL64.
922
923
924Tools and other miscellany
925
926- ftpmirror: Call to main() is wrapped in if __name__ == "__main__".
927
928- freeze: The modulefinder now works with 2.0 opcodes.
929
Tim Petersa3a3a032000-11-30 05:22:44 +0000930- IDLE:
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000931 Move hackery of sys.argv until after the Tk instance has been
932 created, which allows the application-specific Tkinter
933 initialization to be executed if present; also pass an explicit
934 className parameter to the Tk() constructor.
Fred Drake64bb3802000-09-26 16:21:35 +0000935
Jeremy Hylton1b618592000-09-26 05:32:36 +0000936
937What's new in 2.0 beta 1?
938=========================
939
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000940Source Incompatibilities
941------------------------
942
943None. Note that 1.6 introduced several incompatibilities with 1.5.2,
944such as single-argument append(), connect() and bind(), and changes to
945str(long) and repr(float).
946
947
948Binary Incompatibilities
949------------------------
950
951- Third party extensions built for Python 1.5.x or 1.6 cannot be used
952with Python 2.0; these extensions will have to be rebuilt for Python
9532.0.
954
955- On Windows, attempting to import a third party extension built for
956Python 1.5.x or 1.6 results in an immediate crash; there's not much we
957can do about this. Check your PYTHONPATH environment variable!
958
959- Python bytecode files (*.pyc and *.pyo) are not compatible between
960releases.
961
962
963Overview of Changes Since 1.6
964-----------------------------
965
966There are many new modules (including brand new XML support through
967the xml package, and i18n support through the gettext module); a list
968of all new modules is included below. Lots of bugs have been fixed.
969
Jeremy Hylton24c3d602000-09-05 19:36:26 +0000970The process for making major new changes to the language has changed
971since Python 1.6. Enhancements must now be documented by a Python
972Enhancement Proposal (PEP) before they can be accepted.
973
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000974There are several important syntax enhancements, described in more
975detail below:
976
977 - Augmented assignment, e.g. x += 1
978
979 - List comprehensions, e.g. [x**2 for x in range(10)]
980
981 - Extended import statement, e.g. import Module as Name
982
983 - Extended print statement, e.g. print >> file, "Hello"
984
985Other important changes:
986
987 - Optional collection of cyclical garbage
988
Jeremy Hylton24c3d602000-09-05 19:36:26 +0000989Python Enhancement Proposal (PEP)
990---------------------------------
991
992PEP stands for Python Enhancement Proposal. A PEP is a design
993document providing information to the Python community, or describing
994a new feature for Python. The PEP should provide a concise technical
995specification of the feature and a rationale for the feature.
996
997We intend PEPs to be the primary mechanisms for proposing new
998features, for collecting community input on an issue, and for
999documenting the design decisions that have gone into Python. The PEP
1000author is responsible for building consensus within the community and
1001documenting dissenting opinions.
1002
1003The PEPs are available at http://python.sourceforge.net/peps/.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001004
1005Augmented Assignment
1006--------------------
1007
1008This must have been the most-requested feature of the past years!
1009Eleven new assignment operators were added:
1010
Guido van Rossume905e952000-09-05 12:42:46 +00001011 += -= *= /= %= **= <<= >>= &= ^= |=
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001012
1013For example,
1014
1015 A += B
1016
1017is similar to
1018
1019 A = A + B
1020
1021except that A is evaluated only once (relevant when A is something
1022like dict[index].attr).
1023
1024However, if A is a mutable object, A may be modified in place. Thus,
1025if A is a number or a string, A += B has the same effect as A = A+B
1026(except A is only evaluated once); but if a is a list, A += B has the
1027same effect as A.extend(B)!
1028
1029Classes and built-in object types can override the new operators in
1030order to implement the in-place behavior; the not-in-place behavior is
1031used automatically as a fallback when an object doesn't implement the
1032in-place behavior. For classes, the method name is derived from the
1033method name for the corresponding not-in-place operator by inserting
1034an 'i' in front of the name, e.g. __iadd__ implements in-place
1035__add__.
1036
1037Augmented assignment was implemented by Thomas Wouters.
1038
1039
1040List Comprehensions
1041-------------------
1042
1043This is a flexible new notation for lists whose elements are computed
1044from another list (or lists). The simplest form is:
1045
1046 [<expression> for <variable> in <sequence>]
1047
Guido van Rossum56db0952000-09-06 23:34:25 +00001048For example, [i**2 for i in range(4)] yields the list [0, 1, 4, 9].
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001049This is more efficient than a for loop with a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001050
1051You can also add a condition:
1052
1053 [<expression> for <variable> in <sequence> if <condition>]
1054
1055For example, [w for w in words if w == w.lower()] would yield the list
1056of words that contain no uppercase characters. This is more efficient
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001057than a for loop with an if statement and a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001058
1059You can also have nested for loops and more than one 'if' clause. For
1060example, here's a function that flattens a sequence of sequences::
1061
1062 def flatten(seq):
1063 return [x for subseq in seq for x in subseq]
1064
1065 flatten([[0], [1,2,3], [4,5], [6,7,8,9], []])
1066
1067This prints
1068
1069 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
1070
1071List comprehensions originated as a patch set from Greg Ewing; Skip
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001072Montanaro and Thomas Wouters also contributed. Described by PEP 202.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001073
1074
1075Extended Import Statement
1076-------------------------
1077
1078Many people have asked for a way to import a module under a different
1079name. This can be accomplished like this:
1080
1081 import foo
1082 bar = foo
1083 del foo
1084
1085but this common idiom gets old quickly. A simple extension of the
1086import statement now allows this to be written as follows:
1087
1088 import foo as bar
1089
1090There's also a variant for 'from ... import':
1091
1092 from foo import bar as spam
1093
1094This also works with packages; e.g. you can write this:
1095
1096 import test.regrtest as regrtest
1097
1098Note that 'as' is not a new keyword -- it is recognized only in this
1099context (this is only possible because the syntax for the import
1100statement doesn't involve expressions).
1101
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001102Implemented by Thomas Wouters. Described by PEP 221.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001103
1104
1105Extended Print Statement
1106------------------------
1107
1108Easily the most controversial new feature, this extension to the print
1109statement adds an option to make the output go to a different file
1110than the default sys.stdout.
1111
1112For example, to write an error message to sys.stderr, you can now
1113write:
1114
1115 print >> sys.stderr, "Error: bad dog!"
1116
1117As a special feature, if the expression used to indicate the file
Fred Drake45888ff2000-09-29 17:09:11 +00001118evaluates to None, the current value of sys.stdout is used. Thus:
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001119
1120 print >> None, "Hello world"
1121
1122is equivalent to
1123
1124 print "Hello world"
1125
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001126Design and implementation by Barry Warsaw. Described by PEP 214.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001127
1128
1129Optional Collection of Cyclical Garbage
1130---------------------------------------
1131
1132Python is now equipped with a garbage collector that can hunt down
1133cyclical references between Python objects. It's no replacement for
1134reference counting; in fact, it depends on the reference counts being
1135correct, and decides that a set of objects belong to a cycle if all
1136their reference counts can be accounted for from their references to
1137each other. This devious scheme was first proposed by Eric Tiedemann,
1138and brought to implementation by Neil Schemenauer.
1139
1140There's a module "gc" that lets you control some parameters of the
1141garbage collection. There's also an option to the configure script
1142that lets you enable or disable the garbage collection. In 2.0b1,
1143it's on by default, so that we (hopefully) can collect decent user
1144experience with this new feature. There are some questions about its
Fred Drake9f11cf82000-09-29 17:54:40 +00001145performance. If it proves to be too much of a problem, we'll turn it
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001146off by default in the final 2.0 release.
1147
1148
1149Smaller Changes
1150---------------
1151
1152A new function zip() was added. zip(seq1, seq2, ...) is equivalent to
1153map(None, seq1, seq2, ...) when the sequences have the same length;
1154i.e. zip([1,2,3], [10,20,30]) returns [(1,10), (2,20), (3,30)]. When
1155the lists are not all the same length, the shortest list wins:
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001156zip([1,2,3], [10,20]) returns [(1,10), (2,20)]. See PEP 201.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001157
1158sys.version_info is a tuple (major, minor, micro, level, serial).
1159
1160Dictionaries have an odd new method, setdefault(key, default).
1161dict.setdefault(key, default) returns dict[key] if it exists; if not,
1162it sets dict[key] to default and returns that value. Thus:
1163
1164 dict.setdefault(key, []).append(item)
1165
1166does the same work as this common idiom:
1167
1168 if not dict.has_key(key):
1169 dict[key] = []
1170 dict[key].append(item)
1171
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001172There are two new variants of SyntaxError that are raised for
1173indentation-related errors: IndentationError and TabError.
1174
1175Changed \x to consume exactly two hex digits; see PEP 223. Added \U
1176escape that consumes exactly eight hex digits.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001177
1178The limits on the size of expressions and file in Python source code
1179have been raised from 2**16 to 2**32. Previous versions of Python
1180were limited because the maximum argument size the Python VM accepted
1181was 2**16. This limited the size of object constructor expressions,
1182e.g. [1,2,3] or {'a':1, 'b':2}, and the size of source files. This
1183limit was raised thanks to a patch by Charles Waldman that effectively
1184fixes the problem. It is now much more likely that you will be
1185limited by available memory than by an arbitrary limit in Python.
1186
1187The interpreter's maximum recursion depth can be modified by Python
1188programs using sys.getrecursionlimit and sys.setrecursionlimit. This
1189limit is the maximum number of recursive calls that can be made by
1190Python code. The limit exists to prevent infinite recursion from
1191overflowing the C stack and causing a core dump. The default value is
11921000. The maximum safe value for a particular platform can be found
1193by running Misc/find_recursionlimit.py.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001194
1195New Modules and Packages
1196------------------------
1197
1198atexit - for registering functions to be called when Python exits.
1199
1200imputil - Greg Stein's alternative API for writing custom import
1201hooks.
1202
1203pyexpat - an interface to the Expat XML parser, contributed by Paul
1204Prescod.
1205
1206xml - a new package with XML support code organized (so far) in three
1207subpackages: xml.dom, xml.sax, and xml.parsers. Describing these
1208would fill a volume. There's a special feature whereby a
1209user-installed package named _xmlplus overrides the standard
1210xmlpackage; this is intended to give the XML SIG a hook to distribute
1211backwards-compatible updates to the standard xml package.
1212
1213webbrowser - a platform-independent API to launch a web browser.
1214
1215
Guido van Rossume905e952000-09-05 12:42:46 +00001216Changed Modules
1217---------------
1218
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001219array -- new methods for array objects: count, extend, index, pop, and
1220remove
1221
1222binascii -- new functions b2a_hex and a2b_hex that convert between
1223binary data and its hex representation
1224
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001225calendar -- Many new functions that support features including control
1226over which day of the week is the first day, returning strings instead
1227of printing them. Also new symbolic constants for days of week,
1228e.g. MONDAY, ..., SUNDAY.
1229
1230cgi -- FieldStorage objects have a getvalue method that works like a
1231dictionary's get method and returns the value attribute of the object.
1232
1233ConfigParser -- The parser object has new methods has_option,
1234remove_section, remove_option, set, and write. They allow the module
1235to be used for writing config files as well as reading them.
1236
1237ftplib -- ntransfercmd(), transfercmd(), and retrbinary() all now
Guido van Rossume905e952000-09-05 12:42:46 +00001238optionally support the RFC 959 REST command.
1239
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001240gzip -- readline and readlines now accept optional size arguments
Guido van Rossume905e952000-09-05 12:42:46 +00001241
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001242httplib -- New interfaces and support for HTTP/1.1 by Greg Stein. See
1243the module doc strings for details.
Guido van Rossum830ca2a2000-09-05 15:34:16 +00001244
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001245locale -- implement getdefaultlocale for Win32 and Macintosh
1246
1247marshal -- no longer dumps core when marshaling deeply nested or
1248recursive data structures
1249
1250os -- new functions isatty, seteuid, setegid, setreuid, setregid
1251
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001252os/popen2 -- popen2/popen3/popen4 support under Windows. popen2/popen3
1253support under Unix.
1254
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001255os/pty -- support for openpty and forkpty
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001256
1257os.path -- fix semantics of os.path.commonprefix
1258
1259smtplib -- support for sending very long messages
1260
1261socket -- new function getfqdn()
1262
1263readline -- new functions to read, write and truncate history files.
1264The readline section of the library reference manual contains an
1265example.
1266
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001267select -- add interface to poll system call
1268
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001269shutil -- new copyfileobj function
1270
1271SimpleHTTPServer, CGIHTTPServer -- Fix problems with buffering in the
1272HTTP server.
1273
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001274Tkinter -- optimization of function flatten
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001275
1276urllib -- scans environment variables for proxy configuration,
Tim Peters8b092332000-09-05 20:15:25 +00001277e.g. http_proxy.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001278
1279whichdb -- recognizes dumbdbm format
Guido van Rossume905e952000-09-05 12:42:46 +00001280
1281
1282Obsolete Modules
1283----------------
1284
1285None. However note that 1.6 made a whole slew of modules obsolete:
1286stdwin, soundex, cml, cmpcache, dircache, dump, find, grep, packmail,
1287poly, zmod, strop, util, whatsound.
1288
1289
1290Changed, New, Obsolete Tools
1291----------------------------
1292
Tim Peters8b092332000-09-05 20:15:25 +00001293None.
Guido van Rossume905e952000-09-05 12:42:46 +00001294
1295
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001296C-level Changes
1297---------------
1298
1299Several cleanup jobs were carried out throughout the source code.
1300
1301All C code was converted to ANSI C; we got rid of all uses of the
1302Py_PROTO() macro, which makes the header files a lot more readable.
1303
1304Most of the portability hacks were moved to a new header file,
1305pyport.h; several other new header files were added and some old
1306header files were removed, in an attempt to create a more rational set
1307of header files. (Few of these ever need to be included explicitly;
1308they are all included by Python.h.)
1309
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001310Trent Mick ensured portability to 64-bit platforms, under both Linux
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001311and Win64, especially for the new Intel Itanium processor. Mick also
1312added large file support for Linux64 and Win64.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001313
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001314The C APIs to return an object's size have been update to consistently
1315use the form PyXXX_Size, e.g. PySequence_Size and PyDict_Size. In
1316previous versions, the abstract interfaces used PyXXX_Length and the
1317concrete interfaces used PyXXX_Size. The old names,
1318e.g. PyObject_Length, are still available for backwards compatibility
1319at the API level, but are deprecated.
1320
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001321The PyOS_CheckStack function has been implemented on Windows by
1322Fredrik Lundh. It prevents Python from failing with a stack overflow
1323on Windows.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001324
1325The GC changes resulted in creation of two new slots on object,
1326tp_traverse and tp_clear. The augmented assignment changes result in
Guido van Rossum4338a282000-09-06 13:02:08 +00001327the creation of a new slot for each in-place operator.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001328
1329The GC API creates new requirements for container types implemented in
Guido van Rossum4338a282000-09-06 13:02:08 +00001330C extension modules. See Include/objimpl.h for details.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001331
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001332PyErr_Format has been updated to automatically calculate the size of
1333the buffer needed to hold the formatted result string. This change
1334prevents crashes caused by programmer error.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001335
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001336New C API calls: PyObject_AsFileDescriptor, PyErr_WriteUnraisable.
Guido van Rossume905e952000-09-05 12:42:46 +00001337
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001338PyRun_AnyFileEx, PyRun_SimpleFileEx, PyRun_FileEx -- New functions
1339that are the same as their non-Ex counterparts except they take an
1340extra flag argument that tells them to close the file when done.
1341
1342XXX There were other API changes that should be fleshed out here.
Guido van Rossumab9d6f01998-08-10 22:01:13 +00001343
Tim Peters8b092332000-09-05 20:15:25 +00001344
1345Windows Changes
1346---------------
1347
1348New popen2/popen3/peopen4 in os module (see Changed Modules above).
1349
1350os.popen is much more usable on Windows 95 and 98. See Microsoft
1351Knowledge Base article Q150956. The Win9x workaround described there
1352is implemented by the new w9xpopen.exe helper in the root of your
1353Python installation. Note that Python uses this internally; it is not
1354a standalone program.
1355
1356Administrator privileges are no longer required to install Python
1357on Windows NT or Windows 2000. If you have administrator privileges,
1358Python's registry info will be written under HKEY_LOCAL_MACHINE.
1359Otherwise the installer backs off to writing Python's registry info
Guido van Rossum4338a282000-09-06 13:02:08 +00001360under HKEY_CURRENT_USER. The latter is sufficient for all "normal"
Tim Peters8b092332000-09-05 20:15:25 +00001361uses of Python, but will prevent some advanced uses from working
1362(for example, running a Python script as an NT service, or possibly
1363from CGI).
1364
1365[This was new in 1.6] The installer no longer runs a separate Tcl/Tk
1366installer; instead, it installs the needed Tcl/Tk files directly in the
1367Python directory. If you already have a Tcl/Tk installation, this
1368wastes some disk space (about 4 Megs) but avoids problems with
1369conflicting Tcl/Tk installations, and makes it much easier for Python
1370to ensure that Tcl/Tk can find all its files.
1371
1372[This was new in 1.6] The Windows installer now installs by default in
1373\Python20\ on the default volume, instead of \Program Files\Python-2.0\.
1374
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001375
1376Updates to the changes between 1.5.2 and 1.6
1377--------------------------------------------
1378
1379The 1.6 NEWS file can't be changed after the release is done, so here
1380is some late-breaking news:
1381
1382New APIs in locale.py: normalize(), getdefaultlocale(), resetlocale(),
1383and changes to getlocale() and setlocale().
1384
1385The new module is now enabled per default.
1386
1387It is not true that the encodings codecs cannot be used for normal
1388strings: the string.encode() (which is also present on 8-bit strings
1389!) allows using them for 8-bit strings too, e.g. to convert files from
1390cp1252 (Windows) to latin-1 or vice-versa.
1391
1392Japanese codecs are available from Tamito KAJIYAMA:
1393http://pseudo.grad.sccs.chukyo-u.ac.jp/~kajiyama/python/
1394
1395
Guido van Rossumab9d6f01998-08-10 22:01:13 +00001396======================================================================