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Martin v. Löwis0411f6f2001-03-21 08:01:39 +00001What's New in Python 2.1 beta 2?
2================================
3
Guido van Rossum053ae352001-03-22 14:17:21 +00004(Unlisted are many fixed bugs, more documentation, etc.)
5
Martin v. Löwis0411f6f2001-03-21 08:01:39 +00006Core language, builtins, and interpreter
7
Guido van Rossum053ae352001-03-22 14:17:21 +00008- The nested scopes work (enabled by "from __future__ import
9 nested_scopes") is completed; in particular, the future now extends
10 into code executed through exec, eval() and execfile(), and into the
11 interactive interpreter.
12
13- When calling a base class method (e.g. BaseClass.__init__(self)),
14 this is now allowed even if self is not strictly spoken a class
15 instance (e.g. when using metaclasses or the Don Beaudry hook).
16
17- Slice objects are now comparable but not hashable; this prevents
18 dict[:] from being accepted but meaningless.
19
20- Complex division is now calculated using less braindead algorithms.
21 This doesn't change semantics except it's more likely to give useful
22 results in extreme cases. Complex repr() now uses full precision
23 like float repr().
24
25- sgmllib.py now calls handle_decl() for simple <!...> declarations.
26
Martin v. Löwis0411f6f2001-03-21 08:01:39 +000027Standard library
28
Guido van Rossum053ae352001-03-22 14:17:21 +000029- unittest.py, a unit testing framework by Steve Purcell (PyUNIT,
30 inspired by JUnit), is now part of the standard library. You now
31 have a choice of two testing frameworks: unittest requires you to
32 write testcases as separate code, doctest gathers them from
33 docstrings. Both approaches have their advantages and
34 disadvantages.
35
36- A new module Tix was added, which wraps the Tix extension library
37 for Tk. With that module, it is not necessary to statically link
38 Tix with _tkinter, since Tix will be loaded with Tcl's "package
39 require" command. See Demo/tix/.
40
41- tzparse.py is now obsolete.
42
43- In gzip.py, the seek() and tell() methods are removed -- they were
44 non-functional anyway, and it's better if callers can test for their
45 existence with hasattr().
46
47Python/C API
48
49- PyDict_Next(): it is now safe to call PyDict_SetItem() with a key
50 that's already in the dictionary during a PyDict_Next() iteration.
51 This used to fail occasionally when a dictionary resize operation
52 could be triggered that would rehash all the keys. All other
53 modifications to the dictionary are still off-limits during a
54 PyDict_Next() iteration!
55
56- New extended APIs related to passing compiler variables around.
57
58- New abstract APIs PyObject_IsInstance(), PyObject_IsSubclass()
59 implement isinstance() and issubclass().
60
61- Py_BuildValue() now has a "D" conversion to create a Python complex
62 number from a Py_complex C value.
Martin v. Löwis0411f6f2001-03-21 08:01:39 +000063
Tim Peters2fe289a2001-03-01 22:19:38 +000064What's New in Python 2.1 beta 1?
65================================
Tim Petersd66595f2001-02-04 03:09:53 +000066
67Core language, builtins, and interpreter
68
Guido van Rossum9d0fbde2001-03-02 14:00:32 +000069- Following an outcry from the community about the amount of code
70 broken by the nested scopes feature introduced in 2.1a2, we decided
71 to make this feature optional, and to wait until Python 2.2 (or at
72 least 6 months) to make it standard. The option can be enabled on a
73 per-module basis by adding "from __future__ import nested_scopes" at
74 the beginning of a module (before any other statements, but after
75 comments and an optional docstring). See PEP 236 (Back to the
76 __future__) for a description of the __future__ statement. PEP 227
77 (Statically Nested Scopes) has been updated to reflect this change,
78 and to clarify the semantics in a number of endcases.
79
80- The nested scopes code, when enabled, has been hardened, and most
81 bugs and memory leaks in it have been fixed.
82
83- Compile-time warnings are now generated for a number of conditions
84 that will break or change in meaning when nested scopes are enabled:
85
86 - Using "from...import *" or "exec" without in-clause in a function
87 scope that also defines a lambda or nested function with one or
88 more free (non-local) variables. The presence of the import* or
89 bare exec makes it impossible for the compiler to determine the
90 exact set of local variables in the outer scope, which makes it
91 impossible to determine the bindings for free variables in the
92 inner scope. To avoid the warning about import *, change it into
93 an import of explicitly name object, or move the import* statement
94 to the global scope; to avoid the warning about bare exec, use
95 exec...in... (a good idea anyway -- there's a possibility that
96 bare exec will be deprecated in the future).
97
98 - Use of a global variable in a nested scope with the same name as a
99 local variable in a surrounding scope. This will change in
100 meaning with nested scopes: the name in the inner scope will
101 reference the variable in the outer scope rather than the global
102 of the same name. To avoid the warning, either rename the outer
103 variable, or use a global statement in the inner function.
104
Neil Schemenauera35c6882001-02-27 04:45:05 +0000105- An optional object allocator has been included. This allocator is
106 optimized for Python objects and should be faster and use less memory
107 than the standard system allocator. It is not enabled by default
108 because of possible thread safety problems. The allocator is only
109 protected by the Python interpreter lock and it is possible that some
110 extension modules require a thread safe allocator. The object
111 allocator can be enabled by providing the "--with-pymalloc" option to
112 configure.
113
Tim Petersd66595f2001-02-04 03:09:53 +0000114Standard library
115
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000116- pyexpat now detects the expat version if expat.h defines it. A
117 number of additional handlers are provided, which are only available
118 since expat 1.95. In addition, the methods SetParamEntityParsing and
119 GetInputContext of Parser objects are available with 1.95.x
120 only. Parser objects now provide the ordered_attributes and
121 specified_attributes attributes. A new module expat.model was added,
122 which offers a number of additional constants if 1.95.x is used.
123
124- xml.dom offers the new functions registerDOMImplementation and
125 getDOMImplementation.
126
127- xml.dom.minidom offers a toprettyxml method. A number of DOM
128 conformance issues have been resolved. In particular, Element now
129 has an hasAttributes method, and the handling of namespaces was
130 improved.
131
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +0000132- Ka-Ping Yee contributed two new modules: inspect.py, a module for
133 getting information about live Python code, and pydoc.py, a module
134 for interactively converting docstrings to HTML or text.
135 Tools/scripts/pydoc, which is now automatically installed into
Tim Peters1eff7962001-03-01 02:31:33 +0000136 <prefix>/bin, uses pydoc.py to display documentation; try running
Guido van Rossume3955a82001-03-02 14:05:59 +0000137 "pydoc -h" for instructions. "pydoc -g" pops up a small GUI that
138 lets you browse the module docstrings using a web browser.
Andrew M. Kuchlingd6a1d792001-02-28 21:05:42 +0000139
Tim Peters1eff7962001-03-01 02:31:33 +0000140- New library module difflib.py, primarily packaging the SequenceMatcher
141 class at the heart of the popular ndiff.py file-comparison tool.
142
143- doctest.py (a framework for verifying Python code examples in docstrings)
144 is now part of the std library.
145
Tim Petersd66595f2001-02-04 03:09:53 +0000146Windows changes
147
Guido van Rossume3955a82001-03-02 14:05:59 +0000148- A new entry in the Start menu, "Module Docs", runs "pydoc -g" -- a
149 small GUI that lets you browse the module docstrings using your
150 default web browser.
151
Tim Peters1eff7962001-03-01 02:31:33 +0000152- Import is now case-sensitive. PEP 235 (Import on Case-Insensitive
153 Platforms) is implemented. See
154
155 http://python.sourceforge.net/peps/pep-0235.html
156
157 for full details, especially the "Current Lower-Left Semantics" section.
158 The new Windows import rules are simpler than before:
159
160 A. If the PYTHONCASEOK environment variable exists, same as
161 before: silently accept the first case-insensitive match of any
162 kind; raise ImportError if none found.
163
164 B. Else search sys.path for the first case-sensitive match; raise
165 ImportError if none found.
166
167 The same rules have been implented on other platforms with case-
168 insensitive but case-preserving filesystems too (including Cygwin, and
169 several flavors of Macintosh operating systems).
Tim Petersd66595f2001-02-04 03:09:53 +0000170
Tim Peters25a9ce32001-02-19 07:06:36 +0000171- winsound module: Under Win9x, winsound.Beep() now attempts to simulate
172 what it's supposed to do (and does do under NT and 2000) via direct
173 port manipulation. It's unknown whether this will work on all systems,
Tim Peters1eff7962001-03-01 02:31:33 +0000174 but it does work on my Win98SE systems now and was known to be useless on
Tim Peters25a9ce32001-02-19 07:06:36 +0000175 all Win9x systems before.
176
Tim Peters1eff7962001-03-01 02:31:33 +0000177- Build: Subproject _test (effectively) renamed to _testcapi.
178
Tim Peters2fe289a2001-03-01 22:19:38 +0000179New platforms
180
181- 2.1 should compile and run out of the box under MacOS X, even using HFS+.
182 Thanks to Steven Majewski!
183
184- 2.1 should compile and run out of the box on Cygwin. Thanks to Jason
185 Tishler!
186
Guido van Rossum9089b272001-03-02 06:49:50 +0000187- 2.1 contains new files and patches for RISCOS, thanks to Dietmar
188 Schwertberger! See RISCOS/README for more information -- it seems
189 that because of the bizarre filename conventions on RISCOS, no port
190 to that platform is easy. Note that the new variable os.endsep is
191 silently supported in order to make life easier on this platform,
192 but we don't advertise it because it's not worth for most folks to
193 care about RISCOS portability.
194
Tim Peters25a9ce32001-02-19 07:06:36 +0000195
Tim Petersd7b5e882001-01-25 03:36:26 +0000196What's New in Python 2.1 alpha 2?
197=================================
Tim Peters40ead762001-01-27 05:35:26 +0000198
Tim Petersd7b5e882001-01-25 03:36:26 +0000199Core language, builtins, and interpreter
200
Jeremy Hylton4589bd82001-02-01 20:38:45 +0000201- Scopes nest. If a name is used in a function or class, but is not
202 local, the definition in the nearest enclosing function scope will
203 be used. One consequence of this change is that lambda statements
204 could reference variables in the namespaces where the lambda is
205 defined. In some unusual cases, this change will break code.
206
207 In all previous version of Python, names were resolved in exactly
208 three namespaces -- the local namespace, the global namespace, and
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000209 the builtin namespace. According to this old definition, if a
Jeremy Hylton4589bd82001-02-01 20:38:45 +0000210 function A is defined within a function B, the names bound in B are
211 not visible in A. The new rules make names bound in B visible in A,
212 unless A contains a name binding that hides the binding in B.
213
214 Section 4.1 of the reference manual describes the new scoping rules
215 in detail. The test script in Lib/test/test_scope.py demonstrates
216 some of the effects of the change.
217
218 The new rules will cause existing code to break if it defines nested
219 functions where an outer function has local variables with the same
220 name as globals or builtins used by the inner function. Example:
221
222 def munge(str):
223 def helper(x):
224 return str(x)
225 if type(str) != type(''):
226 str = helper(str)
227 return str.strip()
228
229 Under the old rules, the name str in helper() is bound to the
230 builtin function str(). Under the new rules, it will be bound to
231 the argument named str and an error will occur when helper() is
232 called.
233
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000234- The compiler will report a SyntaxError if "from ... import *" occurs
235 in a function or class scope. The language reference has documented
236 that this case is illegal, but the compiler never checked for it.
237 The recent introduction of nested scope makes the meaning of this
238 form of name binding ambiguous. In a future release, the compiler
239 may allow this form when there is no possibility of ambiguity.
240
Tim Peters40ead762001-01-27 05:35:26 +0000241- repr(string) is easier to read, now using hex escapes instead of octal,
242 and using \t, \n and \r instead of \011, \012 and \015 (respectively):
243
244 >>> "\texample \r\n" + chr(0) + chr(255)
245 '\texample \r\n\x00\xff' # in 2.1
246 '\011example \015\012\000\377' # in 2.0
247
Moshe Zadka6af0ce02001-01-29 06:41:00 +0000248- Functions are now compared and hashed by identity, not by value, since
249 the func_code attribute is writable.
250
Fred Drakefb9d7122001-02-01 20:00:40 +0000251- Weak references (PEP 205) have been added. This involves a few
252 changes in the core, an extension module (_weakref), and a Python
253 module (weakref). The weakref module is the public interface. It
254 includes support for "explicit" weak references, proxy objects, and
255 mappings with weakly held values.
256
Jeremy Hylton0072d5a2001-02-01 22:53:15 +0000257- A 'continue' statement can now appear in a try block within the body
258 of a loop. It is still not possible to use continue in a finally
Tim Peters9ea17ac2001-02-02 05:57:15 +0000259 clause.
Jeremy Hylton0072d5a2001-02-01 22:53:15 +0000260
Tim Petersd7b5e882001-01-25 03:36:26 +0000261Standard library
262
Barry Warsaw30dbd142001-01-31 22:14:01 +0000263- mailbox.py now has a new class, PortableUnixMailbox which is
264 identical to UnixMailbox but uses a more portable scheme for
265 determining From_ separators. Also, the constructors for all the
266 classes in this module have a new optional `factory' argument, which
267 is a callable used when new message classes must be instantiated by
268 the next() method.
269
Tim Petersd7b5e882001-01-25 03:36:26 +0000270- random.py is now self-contained, and offers all the functionality of
271 the now-deprecated whrandom.py. See the docs for details. random.py
272 also supports new functions getstate() and setstate(), for saving
Tim Petersd52269b2001-01-25 06:23:18 +0000273 and restoring the internal state of the generator; and jumpahead(n),
274 for quickly forcing the internal state to be the same as if n calls to
275 random() had been made. The latter is particularly useful for multi-
276 threaded programs, creating one instance of the random.Random() class for
277 each thread, then using .jumpahead() to force each instance to use a
278 non-overlapping segment of the full period.
Tim Petersd7b5e882001-01-25 03:36:26 +0000279
Tim Peters0de88fc2001-02-01 04:59:18 +0000280- random.py's seed() function is new. For bit-for-bit compatibility with
281 prior releases, use the whseed function instead. The new seed function
282 addresses two problems: (1) The old function couldn't produce more than
283 about 2**24 distinct internal states; the new one about 2**45 (the best
284 that can be done in the Wichmann-Hill generator). (2) The old function
285 sometimes produced identical internal states when passed distinct
286 integers, and there was no simple way to predict when that would happen;
287 the new one guarantees to produce distinct internal states for all
288 arguments in [0, 27814431486576L).
289
Jeremy Hylton4c4fda02001-02-02 03:29:24 +0000290- The socket module now supports raw packets on Linux. The socket
291 family is AF_PACKET.
292
Tim Peters9ea17ac2001-02-02 05:57:15 +0000293- test_capi.py is a start at running tests of the Python C API. The tests
294 are implemented by the new Modules/_testmodule.c.
295
Jeremy Hyltond6b1cf92001-02-02 20:06:28 +0000296- A new extension module, _symtable, provides provisional access to the
297 internal symbol table used by the Python compiler. A higher-level
298 interface will be added on top of _symtable in a future release.
299
Andrew M. Kuchlingdebc3522001-02-22 15:53:21 +0000300- Removed the obsolete soundex module.
301
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000302- xml.dom.minidom now uses the standard DOM exceptions. Node supports
303 the isSameNode method; NamedNodeMap the get method.
304
305- xml.sax.expatreader supports the lexical handler property; it
306 generates comment, startCDATA, and endCDATA events.
307
Tim Petersee826f82001-01-31 19:39:44 +0000308Windows changes
309
310- Build procedure: the zlib project is built in a different way that
311 ensures the zlib header files used can no longer get out of synch with
Tim Peters9ea17ac2001-02-02 05:57:15 +0000312 the zlib binary used. See PCbuild\readme.txt for details. Your old
313 zlib-related directories can be deleted; you'll need to download fresh
314 source for zlib and unpack it into a new directory.
Tim Petersee826f82001-01-31 19:39:44 +0000315
Tim Peters9ea17ac2001-02-02 05:57:15 +0000316- Build: New subproject _test for the benefit of test_capi.py (see above).
317
Tim Petersb16c56f2001-02-02 21:24:51 +0000318- Build: New subproject _symtable, for new DLL _symtable.pyd (a nascent
319 interface to some Python compiler internals).
320
321- Build: Subproject ucnhash is gone, since the code was folded into the
Tim Peters9ea17ac2001-02-02 05:57:15 +0000322 unicodedata subproject.
Tim Petersd7b5e882001-01-25 03:36:26 +0000323
Tim Petersa3a3a032000-11-30 05:22:44 +0000324What's New in Python 2.1 alpha 1?
325=================================
326
327Core language, builtins, and interpreter
328
Marc-André Lemburgebb195b2001-01-20 10:34:52 +0000329- There is a new Unicode companion to the PyObject_Str() API
330 called PyObject_Unicode(). It behaves in the same way as the
331 former, but assures that the returned value is an Unicode object
332 (applying the usual coercion if necessary).
Marc-André Lemburgad7c98e2001-01-17 17:09:53 +0000333
Guido van Rossumf98eda02001-01-17 15:54:45 +0000334- The comparison operators support "rich comparison overloading" (PEP
335 207). C extension types can provide a rich comparison function in
336 the new tp_richcompare slot in the type object. The cmp() function
337 and the C function PyObject_Compare() first try the new rich
338 comparison operators before trying the old 3-way comparison. There
339 is also a new C API PyObject_RichCompare() (which also falls back on
340 the old 3-way comparison, but does not constrain the outcome of the
341 rich comparison to a Boolean result).
342
343 The rich comparison function takes two objects (at least one of
344 which is guaranteed to have the type that provided the function) and
345 an integer indicating the opcode, which can be Py_LT, Py_LE, Py_EQ,
346 Py_NE, Py_GT, Py_GE (for <, <=, ==, !=, >, >=), and returns a Python
347 object, which may be NotImplemented (in which case the tp_compare
348 slot function is used as a fallback, if defined).
349
350 Classes can overload individual comparison operators by defining one
351 or more of the methods__lt__, __le__, __eq__, __ne__, __gt__,
Guido van Rossuma88479f2001-01-18 14:28:08 +0000352 __ge__. There are no explicit "reflected argument" versions of
353 these; instead, __lt__ and __gt__ are each other's reflection,
354 likewise for__le__ and __ge__; __eq__ and __ne__ are their own
355 reflection (similar at the C level). No other implications are
356 made; in particular, Python does not assume that == is the Boolean
357 inverse of !=, or that < is the Boolean inverse of >=. This makes
358 it possible to define types with partial orderings.
Guido van Rossumf98eda02001-01-17 15:54:45 +0000359
360 Classes or types that want to implement (in)equality tests but not
361 the ordering operators (i.e. unordered types) should implement ==
362 and !=, and raise an error for the ordering operators.
363
Guido van Rossuma88479f2001-01-18 14:28:08 +0000364 It is possible to define types whose rich comparison results are not
Guido van Rossumf98eda02001-01-17 15:54:45 +0000365 Boolean; e.g. a matrix type might want to return a matrix of bits
366 for A < B, giving elementwise comparisons. Such types should ensure
367 that any interpretation of their value in a Boolean context raises
368 an exception, e.g. by defining __nonzero__ (or the tp_nonzero slot
369 at the C level) to always raise an exception.
370
Guido van Rossuma88479f2001-01-18 14:28:08 +0000371- Complex numbers use rich comparisons to define == and != but raise
372 an exception for <, <=, > and >=. Unfortunately, this also means
373 that cmp() of two complex numbers raises an exception when the two
374 numbers differ. Since it is not mathematically meaningful to compare
375 complex numbers except for equality, I hope that this doesn't break
376 too much code.
377
Tim Peters3389f192001-02-18 08:48:49 +0000378- The outcome of comparing non-numeric objects of different types is
Tim Peters14495852001-02-18 08:28:33 +0000379 not defined by the language, other than that it's arbitrary but
380 consistent (see the Reference Manual). An implementation detail changed
381 in 2.1a1 such that None now compares less than any other object. Code
382 relying on this new behavior (like code that relied on the previous
383 behavior) does so at its own risk.
384
Barry Warsaw573b5412001-01-15 20:43:18 +0000385- Functions and methods now support getting and setting arbitrarily
386 named attributes (PEP 232). Functions have a new __dict__
387 (a.k.a. func_dict) which hold the function attributes. Methods get
388 and set attributes on their underlying im_func. It is a TypeError
389 to set an attribute on a bound method.
390
Guido van Rossum051e3352001-01-15 19:11:10 +0000391- The xrange() object implementation has been improved so that
392 xrange(sys.maxint) can be used on 64-bit platforms. There's still a
393 limitation that in this case len(xrange(sys.maxint)) can't be
394 calculated, but the common idiom "for i in xrange(sys.maxint)" will
395 work fine as long as the index i doesn't actually reach 2**31.
396 (Python uses regular ints for sequence and string indices; fixing
397 that is much more work.)
398
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000399- Two changes to from...import:
400
Guido van Rossumba381232001-02-03 15:06:40 +0000401 1) "from M import X" now works even if (after loading module M)
402 sys.modules['M'] is not a real module; it's basically a getattr()
403 operation with AttributeError exceptions changed into ImportError.
Guido van Rossum1cc8f832001-01-12 16:25:08 +0000404
405 2) "from M import *" now looks for M.__all__ to decide which names to
406 import; if M.__all__ doesn't exist, it uses M.__dict__.keys() but
407 filters out names starting with '_' as before. Whether or not
408 __all__ exists, there's no restriction on the type of M.
409
Guido van Rossumf61f1662001-01-10 20:13:55 +0000410- File objects have a new method, xreadlines(). This is the fastest
411 way to iterate over all lines in a file:
412
413 for line in file.xreadlines():
414 ...do something to line...
415
416 See the xreadlines module (mentioned below) for how to do this for
417 other file-like objects.
418
419- Even if you don't use file.xreadlines(), you may expect a speedup on
420 line-by-line input. The file.readline() method has been optimized
Tim Petersf29b64d2001-01-15 06:33:19 +0000421 quite a bit in platform-specific ways: on systems (like Linux) that
422 support flockfile(), getc_unlocked(), and funlockfile(), those are
423 used by default. On systems (like Windows) without getc_unlocked(),
424 a complicated (but still thread-safe) method using fgets() is used by
425 default.
426
Tim Petersd52269b2001-01-25 06:23:18 +0000427 You can force use of the fgets() method by #define'ing
428 USE_FGETS_IN_GETLINE at build time (it may be faster than
Tim Petersf29b64d2001-01-15 06:33:19 +0000429 getc_unlocked()).
430
Tim Petersd52269b2001-01-25 06:23:18 +0000431 You can force fgets() not to be used by #define'ing
432 DONT_USE_FGETS_IN_GETLINE (this is the first thing to try if std test
Tim Petersf29b64d2001-01-15 06:33:19 +0000433 test_bufio.py fails -- and let us know if it does!).
434
435- In addition, the fileinput module, while still slower than the other
436 methods on most platforms, has been sped up too, by using
437 file.readlines(sizehint).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000438
439- Support for run-time warnings has been added, including a new
440 command line option (-W) to specify the disposition of warnings.
441 See the description of the warnings module below.
442
443- Extensive changes have been made to the coercion code. This mostly
444 affects extension modules (which can now implement mixed-type
445 numerical operators without having to use coercion), but
446 occasionally, in boundary cases the coercion semantics have changed
447 subtly. Since this was a terrible gray area of the language, this
Guido van Rossumae72d872001-01-11 15:00:14 +0000448 is considered an improvement. Also note that __rcmp__ is no longer
Guido van Rossumf61f1662001-01-10 20:13:55 +0000449 supported -- instead of calling __rcmp__, __cmp__ is called with
Guido van Rossuma88479f2001-01-18 14:28:08 +0000450 reflected arguments.
Guido van Rossumf61f1662001-01-10 20:13:55 +0000451
Guido van Rossumf98eda02001-01-17 15:54:45 +0000452- In connection with the coercion changes, a new built-in singleton
453 object, NotImplemented is defined. This can be returned for
454 operations that wish to indicate they are not implemented for a
455 particular combination of arguments. From C, this is
456 Py_NotImplemented.
457
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000458- The interpreter accepts now bytecode files on the command line even
459 if they do not have a .pyc or .pyo extension. On Linux, after executing
460
Martin v. Löwise214baa2001-02-04 22:37:56 +0000461import imp,sys,string
462magic = string.join(["\\x%.2x" % ord(c) for c in imp.get_magic()],"")
463reg = ':pyc:M::%s::%s:' % (magic, sys.executable)
464open("/proc/sys/fs/binfmt_misc/register","wb").write(reg)
Martin v. Löwisbe4c0f52001-01-04 20:30:56 +0000465
466 any byte code file can be used as an executable (i.e. as an argument
467 to execve(2)).
468
Tim Peters9940b802000-12-01 07:59:35 +0000469- %[xXo] formats of negative Python longs now produce a sign
Tim Petersa3a3a032000-11-30 05:22:44 +0000470 character. In 1.6 and earlier, they never produced a sign,
471 and raised an error if the value of the long was too large
472 to fit in a Python int. In 2.0, they produced a sign if and
473 only if too large to fit in an int. This was inconsistent
474 across platforms (because the size of an int varies across
475 platforms), and inconsistent with hex() and oct(). Example:
476
477 >>> "%x" % -0x42L
Tim Peters9940b802000-12-01 07:59:35 +0000478 '-42' # in 2.1
Tim Petersa3a3a032000-11-30 05:22:44 +0000479 'ffffffbe' # in 2.0 and before, on 32-bit machines
480 >>> hex(-0x42L)
481 '-0x42L' # in all versions of Python
482
Tim Peters9940b802000-12-01 07:59:35 +0000483 The behavior of %d formats for negative Python longs remains
484 the same as in 2.0 (although in 1.6 and before, they raised
485 an error if the long didn't fit in a Python int).
486
487 %u formats don't make sense for Python longs, but are allowed
488 and treated the same as %d in 2.1. In 2.0, a negative long
489 formatted via %u produced a sign if and only if too large to
490 fit in an int. In 1.6 and earlier, a negative long formatted
491 via %u raised an error if it was too big to fit in an int.
492
Guido van Rossum3661d392000-12-12 22:10:31 +0000493- Dictionary objects have an odd new method, popitem(). This removes
494 an arbitrary item from the dictionary and returns it (in the form of
495 a (key, value) pair). This can be useful for algorithms that use a
496 dictionary as a bag of "to do" items and repeatedly need to pick one
497 item. Such algorithms normally end up running in quadratic time;
498 using popitem() they can usually be made to run in linear time.
499
Tim Peters36cdad12000-12-29 02:06:45 +0000500Standard library
501
Thomas Woutersfe385252001-01-19 23:16:56 +0000502- In the time module, the time argument to the functions strftime,
503 localtime, gmtime, asctime and ctime is now optional, defaulting to
504 the current time (in the local timezone).
505
Guido van Rossumda91f222001-01-15 16:36:08 +0000506- The ftplib module now defaults to passive mode, which is deemed a
507 more useful default given that clients are often inside firewalls
508 these days. Note that this could break if ftplib is used to connect
509 to a *server* that is inside a firewall, from outside; this is
510 expected to be a very rare situation. To fix that, you can call
511 ftp.set_pasv(0).
512
Martin v. Löwis10a27872001-01-13 09:54:41 +0000513- The module site now treats .pth files not only for path configuration,
514 but also supports extensions to the initialization code: Lines starting
515 with import are executed.
516
Guido van Rossumf61f1662001-01-10 20:13:55 +0000517- There's a new module, warnings, which implements a mechanism for
518 issuing and filtering warnings. There are some new built-in
519 exceptions that serve as warning categories, and a new command line
520 option, -W, to control warnings (e.g. -Wi ignores all warnings, -We
521 turns warnings into errors). warnings.warn(message[, category])
522 issues a warning message; this can also be called from C as
523 PyErr_Warn(category, message).
524
525- A new module xreadlines was added. This exports a single factory
526 function, xreadlines(). The intention is that this code is the
527 absolutely fastest way to iterate over all lines in an open
528 file(-like) object:
529
530 import xreadlines
531 for line in xreadlines.xreadlines(file):
532 ...do something to line...
533
534 This is equivalent to the previous the speed record holder using
535 file.readlines(sizehint). Note that if file is a real file object
536 (as opposed to a file-like object), this is equivalent:
537
538 for line in file.xreadlines():
539 ...do something to line...
540
Tim Peters36cdad12000-12-29 02:06:45 +0000541- The bisect module has new functions bisect_left, insort_left,
542 bisect_right and insort_right. The old names bisect and insort
543 are now aliases for bisect_right and insort_right. XXX_right
544 and XXX_left methods differ in what happens when the new element
545 compares equal to one or more elements already in the list: the
546 XXX_left methods insert to the left, the XXX_right methods to the
Tim Peters742bb6f2001-01-05 08:05:32 +0000547 right. Code that doesn't care where equal elements end up should
548 continue to use the old, short names ("bisect" and "insort").
Tim Peters36cdad12000-12-29 02:06:45 +0000549
Andrew M. Kuchlingf6f3a892001-01-13 14:53:34 +0000550- The new curses.panel module wraps the panel library that forms part
551 of SYSV curses and ncurses. Contributed by Thomas Gellekum.
552
Guido van Rossumf61f1662001-01-10 20:13:55 +0000553- The SocketServer module now sets the allow_reuse_address flag by
554 default in the TCPServer class.
555
556- A new function, sys._getframe(), returns the stack frame pointer of
557 the caller. This is intended only as a building block for
558 higher-level mechanisms such as string interpolation.
559
Martin v. Löwis2a5130e2001-02-27 04:21:58 +0000560- The pyexpat module supports a number of new handlers, which are
561 available only in expat 1.2. If invocation of a callback fails, it
562 will report an additional frame in the traceback. Parser objects
563 participate now in garbage collection. If expat reports an unknown
564 encoding, pyexpat will try to use a Python codec; that works only
565 for single-byte charsets. The parser type objects is exposed as
566 XMLParserObject.
567
568- xml.dom now offers standard definitions for symbolic node type and
569 exception code constants, and a hierarchy of DOM exceptions. minidom
570 was adjusted to use them.
571
572- The conformance of xml.dom.minidom to the DOM specification was
573 improved. It detects a number of additional error cases; the
574 previous/next relationship works even when the tree is modified;
575 Node supports the normalize() method; NamedNodeMap, DocumentType and
576 DOMImplementation classes were added; Element supports the
577 hasAttribute and hasAttributeNS methods; and Text supports the splitText
578 method.
579
Guido van Rossumf61f1662001-01-10 20:13:55 +0000580Build issues
581
Guido van Rossum1e33bdc2001-01-23 03:17:00 +0000582- For Unix (and Unix-compatible) builds, configuration and building of
583 extension modules is now greatly automated. Rather than having to
584 edit the Modules/Setup file to indicate which modules should be
585 built and where their include files and libraries are, a
586 distutils-based setup.py script now takes care of building most
587 extension modules. All extension modules built this way are built
588 as shared libraries. Only a few modules that must be linked
589 statically are still listed in the Setup file; you won't need to
590 edit their configuration.
591
592- Python should now build out of the box on Cygwin. If it doesn't,
593 mail to Jason Tishler (jlt63 at users.sourceforge.net).
Guido van Rossumf61f1662001-01-10 20:13:55 +0000594
595- Python now always uses its own (renamed) implementation of getopt()
596 -- there's too much variation among C library getopt()
597 implementations.
598
599- C++ compilers are better supported; the CXX macro is always set to a
600 C++ compiler if one is found.
Tim Peters36cdad12000-12-29 02:06:45 +0000601
Tim Petersd92dfe02000-12-12 01:18:41 +0000602Windows changes
603
604- select module: By default under Windows, a select() call
605 can specify no more than 64 sockets. Python now boosts
606 this Microsoft default to 512. If you need even more than
607 that, see the MS docs (you'll need to #define FD_SETSIZE
608 and recompile Python from source).
609
Guido van Rossumf61f1662001-01-10 20:13:55 +0000610- Support for Windows 3.1, DOS and OS/2 is gone. The Lib/dos-8x3
611 subdirectory is no more!
612
Tim Petersa3a3a032000-11-30 05:22:44 +0000613
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000614What's New in Python 2.0?
Fred Drake1a640502000-10-16 20:27:25 +0000615=========================
Guido van Rossum61000331997-08-15 04:39:58 +0000616
Guido van Rossum8ed602b2000-09-01 22:34:33 +0000617Below is a list of all relevant changes since release 1.6. Older
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000618changes are in the file HISTORY. If you are making the jump directly
619from Python 1.5.2 to 2.0, make sure to read the section for 1.6 in the
620HISTORY file! Many important changes listed there.
Guido van Rossum61000331997-08-15 04:39:58 +0000621
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000622Alternatively, a good overview of the changes between 1.5.2 and 2.0 is
623the document "What's New in Python 2.0" by Kuchling and Moshe Zadka:
624http://starship.python.net/crew/amk/python/writing/new-python/.
Guido van Rossum1f83cce1997-10-06 21:04:35 +0000625
Guido van Rossumf2ffce02000-09-05 04:38:34 +0000626--Guido van Rossum (home page: http://www.pythonlabs.com/~guido/)
Guido van Rossum437cfe81999-04-08 20:17:57 +0000627
628======================================================================
629
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000630What's new in 2.0 (since release candidate 1)?
631==============================================
632
633Standard library
634
635- The copy_reg module was modified to clarify its intended use: to
636 register pickle support for extension types, not for classes.
637 pickle() will raise a TypeError if it is passed a class.
638
639- Fixed a bug in gettext's "normalize and expand" code that prevented
640 it from finding an existing .mo file.
641
642- Restored support for HTTP/0.9 servers in httplib.
643
Tim Peters989b7b92000-10-16 20:24:53 +0000644- The math module was changed to stop raising OverflowError in case of
645 underflow, and return 0 instead in underflow cases. Whether Python
646 used to raise OverflowError in case of underflow was platform-
647 dependent (it did when the platform math library set errno to ERANGE
648 on underflow).
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000649
650- Fixed a bug in StringIO that occurred when the file position was not
651 at the end of the file and write() was called with enough data to
652 extend past the end of the file.
653
654- Fixed a bug that caused Tkinter error messages to get lost on
655 Windows. The bug was fixed by replacing direct use of
656 interp->result with Tcl_GetStringResult(interp).
657
658- Fixed bug in urllib2 that caused it to fail when it received an HTTP
659 redirect response.
660
661- Several changes were made to distutils: Some debugging code was
662 removed from util. Fixed the installer used when an external zip
663 program (like WinZip) is not found; the source code for this
664 installer is in Misc/distutils. check_lib() was modified to behave
665 more like AC_CHECK_LIB by add other_libraries() as a parameter. The
666 test for whether installed modules are on sys.path was changed to
667 use both normcase() and normpath().
668
Jeremy Hyltond867a2c2000-10-16 20:41:38 +0000669- Several minor bugs were fixed in the xml package (the minidom,
670 pulldom, expatreader, and saxutils modules).
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000671
672- The regression test driver (regrtest.py) behavior when invoked with
673 -l changed: It now reports a count of objects that are recognized as
674 garbage but not freed by the garbage collector.
675
Tim Peters989b7b92000-10-16 20:24:53 +0000676- The regression test for the math module was changed to test
677 exceptional behavior when the test is run in verbose mode. Python
678 cannot yet guarantee consistent exception behavior across platforms,
679 so the exception part of test_math is run only in verbose mode, and
680 may fail on your platform.
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000681
682Internals
683
684- PyOS_CheckStack() has been disabled on Win64, where it caused
685 test_sre to fail.
686
687Build issues
688
689- Changed compiler flags, so that gcc is always invoked with -Wall and
690 -Wstrict-prototypes. Users compiling Python with GCC should see
691 exactly one warning, except if they have passed configure the
Tim Peters989b7b92000-10-16 20:24:53 +0000692 --with-pydebug flag. The expected warning is for getopt() in
Tim Petersadfb94f2000-10-16 20:51:33 +0000693 Modules/main.c. This warning will be fixed for Python 2.1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000694
Tim Petersa3a3a032000-11-30 05:22:44 +0000695- Fixed configure to add -threads argument during linking on OSF1.
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000696
697Tools and other miscellany
698
699- The compiler in Tools/compiler was updated to support the new
700 language features introduced in 2.0: extended print statement, list
701 comprehensions, and augmented assignments. The new compiler should
702 also be backwards compatible with Python 1.5.2; the compiler will
703 always generate code for the version of the interpreter it runs
Tim Petersa3a3a032000-11-30 05:22:44 +0000704 under.
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000705
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000706What's new in 2.0 release candidate 1 (since beta 2)?
707=====================================================
708
Jeremy Hylton6040aaa2000-10-09 21:27:22 +0000709What is release candidate 1?
710
711We believe that release candidate 1 will fix all known bugs that we
712intend to fix for the 2.0 final release. This release should be a bit
713more stable than the previous betas. We would like to see even more
714widespread testing before the final release, so we are producing this
715release candidate. The final release will be exactly the same unless
716any show-stopping (or brown bag) bugs are found by testers of the
717release candidate.
718
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000719All the changes since the last beta release are bug fixes or changes
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000720to support building Python for specific platforms.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000721
722Core language, builtins, and interpreter
723
724- A bug that caused crashes when __coerce__ was used with augmented
725 assignment, e.g. +=, was fixed.
726
727- Raise ZeroDivisionError when raising zero to a negative number,
728 e.g. 0.0 ** -2.0. Note that math.pow is unrelated to the builtin
729 power operator and the result of math.pow(0.0, -2.0) will vary by
730 platform. On Linux, it raises a ValueError.
731
732- A bug in Unicode string interpolation was fixed that occasionally
733 caused errors with formats including "%%". For example, the
734 following expression "%% %s" % u"abc" no longer raises a TypeError.
735
736- Compilation of deeply nested expressions raises MemoryError instead
737 of SyntaxError, e.g. eval("[" * 50 + "]" * 50).
738
739- In 2.0b2 on Windows, the interpreter wrote .pyc files in text mode,
740 rendering them useless. They are now written in binary mode again.
741
742Standard library
743
744- Keyword arguments are now accepted for most pattern and match object
745 methods in SRE, the standard regular expression engine.
746
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000747- In SRE, fixed error with negative lookahead and lookbehind that
Jeremy Hylton32e20ff2000-10-09 19:48:11 +0000748 manifested itself as a runtime error in patterns like "(?<!abc)(def)".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000749
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000750- Several bugs in the Unicode handling and error handling in _tkinter
751 were fixed.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000752
753- Fix memory management errors in Merge() and Tkapp_Call() routines.
754
755- Several changes were made to cStringIO to make it compatible with
756 the file-like object interface and with StringIO. If operations are
757 performed on a closed object, an exception is raised. The truncate
758 method now accepts a position argument and readline accepts a size
Tim Petersa3a3a032000-11-30 05:22:44 +0000759 argument.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000760
761- There were many changes made to the linuxaudiodev module and its
762 test suite; as a result, a short, unexpected audio sample should now
Tim Petersa3a3a032000-11-30 05:22:44 +0000763 play when the regression test is run.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000764
765 Note that this module is named poorly, because it should work
766 correctly on any platform that supports the Open Sound System
Tim Petersa3a3a032000-11-30 05:22:44 +0000767 (OSS).
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000768
769 The module now raises exceptions when errors occur instead of
770 crashing. It also defines the AFMT_A_LAW format (logarithmic A-law
771 audio) and defines a getptr() method that calls the
772 SNDCTL_DSP_GETxPTR ioctl defined in the OSS Programmer's Guide.
773
774- The library_version attribute, introduced in an earlier beta, was
775 removed because it can not be supported with early versions of the C
776 readline library, which provides no way to determine the version at
777 compile-time.
778
779- The binascii module is now enabled on Win64.
780
Tim Peters46446d62000-10-09 21:19:31 +0000781- tokenize.py no longer suffers "recursion depth" errors when parsing
782 programs with very long string literals.
783
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000784Internals
785
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000786- Fixed several buffer overflow vulnerabilities in calculate_path(),
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000787 which is called when the interpreter starts up to determine where
788 the standard library is installed. These vulnerabilities affect all
789 previous versions of Python and can be exploited by setting very
790 long values for PYTHONHOME or argv[0]. The risk is greatest for a
791 setuid Python script, although use of the wrapper in
792 Misc/setuid-prog.c will eliminate the vulnerability.
793
794- Fixed garbage collection bugs in instance creation that were
795 triggered when errors occurred during initialization. The solution,
796 applied in cPickle and in PyInstance_New(), is to call
797 PyObject_GC_Init() after the initialization of the object's
798 container attributes is complete.
799
800- pyexpat adds definitions of PyModule_AddStringConstant and
801 PyModule_AddObject if the Python version is less than 2.0, which
802 provides compatibility with PyXML on Python 1.5.2.
803
804- If the platform has a bogus definition for LONG_BIT (the number of
805 bits in a long), an error will be reported at compile time.
806
807- Fix bugs in _PyTuple_Resize() which caused hard-to-interpret garbage
808 collection crashes and possibly other, unreported crashes.
809
810- Fixed a memory leak in _PyUnicode_Fini().
811
812Build issues
813
814- configure now accepts a --with-suffix option that specifies the
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000815 executable suffix. This is useful for builds on Cygwin and Mac OS
Tim Petersa3a3a032000-11-30 05:22:44 +0000816 X, for example.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000817
818- The mmap.PAGESIZE constant is now initialized using sysconf when
819 possible, which eliminates a dependency on -lucb for Reliant UNIX.
820
821- The md5 file should now compile on all platforms.
822
823- The select module now compiles on platforms that do not define
824 POLLRDNORM and related constants.
825
826- Darwin (Mac OS X): Initial support for static builds on this
Tim Petersa3a3a032000-11-30 05:22:44 +0000827 platform.
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000828
Jeremy Hylton10921202000-10-09 18:34:12 +0000829- BeOS: A number of changes were made to the build and installation
830 process. ar-fake now operates on a directory of object files.
831 dl_export.h is gone, and its macros now appear on the mwcc command
832 line during build on PPC BeOS.
833
Jeremy Hyltond6e20232000-10-16 20:08:38 +0000834- Platform directory in lib/python2.0 is "plat-beos5" (or
Jeremy Hylton10921202000-10-09 18:34:12 +0000835 "plat-beos4", if building on BeOS 4.5), rather than "plat-beos".
Jeremy Hyltoned9e6442000-10-09 18:26:42 +0000836
837- Cygwin: Support for shared libraries, Tkinter, and sockets.
838
839- SunOS 4.1.4_JL: Fix test for directory existence in configure.
840
841Tools and other miscellany
842
843- Removed debugging prints from main used with freeze.
844
Tim Peters46446d62000-10-09 21:19:31 +0000845- IDLE auto-indent no longer crashes when it encounters Unicode
846 characters.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000847
848What's new in 2.0 beta 2 (since beta 1)?
849========================================
850
851Core language, builtins, and interpreter
852
Tim Peters482c0212000-09-26 06:33:09 +0000853- Add support for unbounded ints in %d,i,u,x,X,o formats; for example
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000854 "%d" % 2L**64 == "18446744073709551616".
Jeremy Hylton1b618592000-09-26 05:32:36 +0000855
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000856- Add -h and -V command line options to print the usage message and
857 Python version number and exit immediately.
858
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000859- eval() and exec accept Unicode objects as code parameters.
860
861- getattr() and setattr() now also accept Unicode objects for the
862 attribute name, which are converted to strings using the default
863 encoding before lookup.
864
865- Multiplication on string and Unicode now does proper bounds
866 checking; e.g. 'a' * 65536 * 65536 will raise ValueError, "repeated
867 string is too long."
868
869- Better error message when continue is found in try statement in a
Tim Petersa3a3a032000-11-30 05:22:44 +0000870 loop.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000871
Jeremy Hylton1b618592000-09-26 05:32:36 +0000872
873Standard library and extensions
874
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000875- array: reverse() method of array now works. buffer_info() now does
Jeremy Hylton1b618592000-09-26 05:32:36 +0000876 argument checking; it still takes no arguments.
877
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000878- asyncore/asynchat: Included most recent version from Sam Rushing.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000879
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000880- cgi: Accept '&' or ';' as separator characters when parsing form data.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000881
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000882- CGIHTTPServer: Now works on Windows (and perhaps even Mac).
Jeremy Hylton1b618592000-09-26 05:32:36 +0000883
884- ConfigParser: When reading the file, options spelled in upper case
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000885 letters are now correctly converted to lowercase.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000886
887- copy: Copy Unicode objects atomically.
888
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000889- cPickle: Fail gracefully when copy_reg can't be imported.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000890
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000891- cStringIO: Implemented readlines() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000892
Fred Drake67233bc2000-09-26 16:40:27 +0000893- dbm: Add get() and setdefault() methods to dbm object. Add constant
894 `library' to module that names the library used. Added doc strings
895 and method names to error messages. Uses configure to determine
896 which ndbm.h file to include; Berkeley DB's nbdm and GDBM's ndbm is
897 now available options.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000898
899- distutils: Update to version 0.9.3.
900
901- dl: Add several dl.RTLD_ constants.
902
903- fpectl: Now supported on FreeBSD.
904
905- gc: Add DEBUG_SAVEALL option. When enabled all garbage objects
906 found by the collector will be saved in gc.garbage. This is useful
907 for debugging a program that creates reference cycles.
908
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000909- httplib: Three changes: Restore support for set_debuglevel feature
Jeremy Hylton1b618592000-09-26 05:32:36 +0000910 of HTTP class. Do not close socket on zero-length response. Do not
911 crash when server sends invalid content-length header.
912
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000913- mailbox: Mailbox class conforms better to qmail specifications.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000914
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000915- marshal: When reading a short, sign-extend on platforms where shorts
916 are bigger than 16 bits. When reading a long, repair the unportable
917 sign extension that was being done for 64-bit machines. (It assumed
918 that signed right shift sign-extends.)
919
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000920- operator: Add contains(), invert(), __invert__() as aliases for
921 __contains__(), inv(), and __inv__() respectively.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000922
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000923- os: Add support for popen2() and popen3() on all platforms where
924 fork() exists. (popen4() is still in the works.)
Jeremy Hylton1b618592000-09-26 05:32:36 +0000925
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000926- os: (Windows only:) Add startfile() function that acts like double-
Tim Peters482c0212000-09-26 06:33:09 +0000927 clicking on a file in Explorer (or passing the file name to the
928 DOS "start" command).
Jeremy Hylton1b618592000-09-26 05:32:36 +0000929
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000930- os.path: (Windows, DOS:) Treat trailing colon correctly in
Tim Peters482c0212000-09-26 06:33:09 +0000931 os.path.join. os.path.join("a:", "b") yields "a:b".
Jeremy Hylton1b618592000-09-26 05:32:36 +0000932
933- pickle: Now raises ValueError when an invalid pickle that contains
934 a non-string repr where a string repr was expected. This behavior
935 matches cPickle.
936
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000937- posixfile: Remove broken __del__() method.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000938
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000939- py_compile: support CR+LF line terminators in source file.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000940
941- readline: Does not immediately exit when ^C is hit when readline and
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +0000942 threads are configured. Adds definition of rl_library_version. (The
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000943 latter addition requires GNU readline 2.2 or later.)
Jeremy Hylton1b618592000-09-26 05:32:36 +0000944
945- rfc822: Domain literals returned by AddrlistClass method
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000946 getdomainliteral() are now properly wrapped in brackets.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000947
948- site: sys.setdefaultencoding() should only be called in case the
Tim Peters482c0212000-09-26 06:33:09 +0000949 standard default encoding ("ascii") is changed. This saves quite a
Jeremy Hylton1b618592000-09-26 05:32:36 +0000950 few cycles during startup since the first call to
951 setdefaultencoding() will initialize the codec registry and the
952 encodings package.
953
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000954- socket: Support for size hint in readlines() method of object returned
955 by makefile().
Jeremy Hylton1b618592000-09-26 05:32:36 +0000956
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000957- sre: Added experimental expand() method to match objects. Does not
Jeremy Hylton625915e2000-10-02 13:43:33 +0000958 use buffer interface on Unicode strings. Does not hang if group id
Jeremy Hylton1b618592000-09-26 05:32:36 +0000959 is followed by whitespace.
960
Tim Petersa3a3a032000-11-30 05:22:44 +0000961- StringIO: Size hint in readlines() is now supported as documented.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000962
963- struct: Check ranges for bytes and shorts.
964
965- urllib: Improved handling of win32 proxy settings. Fixed quote and
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000966 quote_plus functions so that the always encode a comma.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000967
968- Tkinter: Image objects are now guaranteed to have unique ids. Set
969 event.delta to zero if Tk version doesn't support mousewheel.
970 Removed some debugging prints.
971
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000972- UserList: now implements __contains__().
Jeremy Hylton1b618592000-09-26 05:32:36 +0000973
Fred Drake67233bc2000-09-26 16:40:27 +0000974- webbrowser: On Windows, use os.startfile() instead of os.popen(),
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000975 which works around a bug in Norton AntiVirus 2000 that leads directly
976 to a Blue Screen freeze.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000977
978- xml: New version detection code allows PyXML to override standard
979 XML package if PyXML version is greater than 0.6.1.
980
Fred Drake64bb3802000-09-26 16:21:35 +0000981- xml.dom: DOM level 1 support for basic XML. Includes xml.dom.minidom
982 (conventional DOM), and xml.dom.pulldom, which allows building the DOM
983 tree only for nodes which are sufficiently interesting to a specific
984 application. Does not provide the HTML-specific extensions. Still
985 undocumented.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000986
Fred Drake64bb3802000-09-26 16:21:35 +0000987- xml.sax: SAX 2 support for Python, including all the handler
988 interfaces needed to process XML 1.0 compliant XML. Some
989 documentation is already available.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000990
Fred Drake64bb3802000-09-26 16:21:35 +0000991- pyexpat: Renamed to xml.parsers.expat since this is part of the new,
992 packagized XML support.
Jeremy Hylton1b618592000-09-26 05:32:36 +0000993
Guido van Rossumf62ed9c2000-09-26 11:16:10 +0000994
Jeremy Hylton1b618592000-09-26 05:32:36 +0000995C API
996
997- Add three new convenience functions for module initialization --
998 PyModule_AddObject(), PyModule_AddIntConstant(), and
999 PyModule_AddStringConstant().
1000
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001001- Cleaned up definition of NULL in C source code; all definitions were
Jeremy Hylton1b618592000-09-26 05:32:36 +00001002 removed and add #error to Python.h if NULL isn't defined after
1003 #include of stdio.h.
1004
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001005- Py_PROTO() macros that were removed in 2.0b1 have been restored for
Jeremy Hylton1b618592000-09-26 05:32:36 +00001006 backwards compatibility (at the source level) with old extensions.
1007
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001008- A wrapper API was added for signal() and sigaction(). Instead of
1009 either function, always use PyOS_getsig() to get a signal handler
1010 and PyOS_setsig() to set one. A new convenience typedef
1011 PyOS_sighandler_t is defined for the type of signal handlers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001012
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001013- Add PyString_AsStringAndSize() function that provides access to the
Jeremy Hylton1b618592000-09-26 05:32:36 +00001014 internal data buffer and size of a string object -- or the default
1015 encoded version of a Unicode object.
1016
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001017- PyString_Size() and PyString_AsString() accept Unicode objects.
1018
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001019- The standard header <limits.h> is now included by Python.h (if it
Fred Drake64bb3802000-09-26 16:21:35 +00001020 exists). INT_MAX and LONG_MAX will always be defined, even if
1021 <limits.h> is not available.
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001022
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001023- PyFloat_FromString takes a second argument, pend, that was
1024 effectively useless. It is now officially useless but preserved for
1025 backwards compatibility. If the pend argument is not NULL, *pend is
1026 set to NULL.
1027
1028- PyObject_GetAttr() and PyObject_SetAttr() now accept Unicode objects
1029 for the attribute name. See note on getattr() above.
1030
1031- A few bug fixes to argument processing for Unicode.
1032 PyArg_ParseTupleAndKeywords() now accepts "es#" and "es".
1033 PyArg_Parse() special cases "s#" for Unicode objects; it returns a
1034 pointer to the default encoded string data instead of to the raw
Tim Petersa3a3a032000-11-30 05:22:44 +00001035 UTF-16.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001036
1037- Py_BuildValue accepts B format (for bgen-generated code).
1038
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001039
Jeremy Hylton1b618592000-09-26 05:32:36 +00001040Internals
1041
1042- On Unix, fix code for finding Python installation directory so that
1043 it works when argv[0] is a relative path.
1044
Andrew M. Kuchlinga1099be2000-12-15 01:16:43 +00001045- Added a true unicode_internal_encode() function and fixed the
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001046 unicode_internal_decode function() to support Unicode objects directly
Jeremy Hylton1b618592000-09-26 05:32:36 +00001047 rather than by generating a copy of the object.
1048
Tim Peters482c0212000-09-26 06:33:09 +00001049- Several of the internal Unicode tables are much smaller now, and
1050 the source code should be much friendlier to weaker compilers.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001051
Jeremy Hylton97693b02000-09-26 17:42:51 +00001052- In the garbage collector: Fixed bug in collection of tuples. Fixed
1053 bug that caused some instances to be removed from the container set
1054 while they were still live. Fixed parsing in gc.set_debug() for
1055 platforms where sizeof(long) > sizeof(int).
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001056
1057- Fixed refcount problem in instance deallocation that only occurred
1058 when Py_REF_DEBUG was defined and Py_TRACE_REFS was not.
1059
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001060- On Windows, getpythonregpath is now protected against null data in
1061 registry key.
1062
1063- On Unix, create .pyc/.pyo files with O_EXCL flag to avoid a race
Tim Petersa3a3a032000-11-30 05:22:44 +00001064 condition.
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001065
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001066
Jeremy Hylton1b618592000-09-26 05:32:36 +00001067Build and platform-specific issues
1068
1069- Better support of GNU Pth via --with-pth configure option.
1070
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001071- Python/C API now properly exposed to dynamically-loaded extension
1072 modules on Reliant UNIX.
Jeremy Hylton1b618592000-09-26 05:32:36 +00001073
1074- Changes for the benefit of SunOS 4.1.4 (really!). mmapmodule.c:
1075 Don't define MS_SYNC to be zero when it is undefined. Added missing
1076 prototypes in posixmodule.c.
1077
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001078- Improved support for HP-UX build. Threads should now be correctly
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001079 configured (on HP-UX 10.20 and 11.00).
Jeremy Hylton1b618592000-09-26 05:32:36 +00001080
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001081- Fix largefile support on older NetBSD systems and OpenBSD by adding
1082 define for TELL64.
1083
1084
1085Tools and other miscellany
1086
1087- ftpmirror: Call to main() is wrapped in if __name__ == "__main__".
1088
1089- freeze: The modulefinder now works with 2.0 opcodes.
1090
Tim Petersa3a3a032000-11-30 05:22:44 +00001091- IDLE:
Jeremy Hyltonfa2e2c12000-09-26 16:31:30 +00001092 Move hackery of sys.argv until after the Tk instance has been
1093 created, which allows the application-specific Tkinter
1094 initialization to be executed if present; also pass an explicit
1095 className parameter to the Tk() constructor.
Fred Drake64bb3802000-09-26 16:21:35 +00001096
Jeremy Hylton1b618592000-09-26 05:32:36 +00001097
1098What's new in 2.0 beta 1?
1099=========================
1100
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001101Source Incompatibilities
1102------------------------
1103
1104None. Note that 1.6 introduced several incompatibilities with 1.5.2,
1105such as single-argument append(), connect() and bind(), and changes to
1106str(long) and repr(float).
1107
1108
1109Binary Incompatibilities
1110------------------------
1111
1112- Third party extensions built for Python 1.5.x or 1.6 cannot be used
1113with Python 2.0; these extensions will have to be rebuilt for Python
11142.0.
1115
1116- On Windows, attempting to import a third party extension built for
1117Python 1.5.x or 1.6 results in an immediate crash; there's not much we
1118can do about this. Check your PYTHONPATH environment variable!
1119
1120- Python bytecode files (*.pyc and *.pyo) are not compatible between
1121releases.
1122
1123
1124Overview of Changes Since 1.6
1125-----------------------------
1126
1127There are many new modules (including brand new XML support through
1128the xml package, and i18n support through the gettext module); a list
1129of all new modules is included below. Lots of bugs have been fixed.
1130
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001131The process for making major new changes to the language has changed
1132since Python 1.6. Enhancements must now be documented by a Python
1133Enhancement Proposal (PEP) before they can be accepted.
1134
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001135There are several important syntax enhancements, described in more
1136detail below:
1137
1138 - Augmented assignment, e.g. x += 1
1139
1140 - List comprehensions, e.g. [x**2 for x in range(10)]
1141
1142 - Extended import statement, e.g. import Module as Name
1143
1144 - Extended print statement, e.g. print >> file, "Hello"
1145
1146Other important changes:
1147
1148 - Optional collection of cyclical garbage
1149
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001150Python Enhancement Proposal (PEP)
1151---------------------------------
1152
1153PEP stands for Python Enhancement Proposal. A PEP is a design
1154document providing information to the Python community, or describing
1155a new feature for Python. The PEP should provide a concise technical
1156specification of the feature and a rationale for the feature.
1157
1158We intend PEPs to be the primary mechanisms for proposing new
1159features, for collecting community input on an issue, and for
1160documenting the design decisions that have gone into Python. The PEP
1161author is responsible for building consensus within the community and
1162documenting dissenting opinions.
1163
1164The PEPs are available at http://python.sourceforge.net/peps/.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001165
1166Augmented Assignment
1167--------------------
1168
1169This must have been the most-requested feature of the past years!
1170Eleven new assignment operators were added:
1171
Guido van Rossume905e952000-09-05 12:42:46 +00001172 += -= *= /= %= **= <<= >>= &= ^= |=
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001173
1174For example,
1175
1176 A += B
1177
1178is similar to
1179
1180 A = A + B
1181
1182except that A is evaluated only once (relevant when A is something
1183like dict[index].attr).
1184
1185However, if A is a mutable object, A may be modified in place. Thus,
1186if A is a number or a string, A += B has the same effect as A = A+B
1187(except A is only evaluated once); but if a is a list, A += B has the
1188same effect as A.extend(B)!
1189
1190Classes and built-in object types can override the new operators in
1191order to implement the in-place behavior; the not-in-place behavior is
1192used automatically as a fallback when an object doesn't implement the
1193in-place behavior. For classes, the method name is derived from the
1194method name for the corresponding not-in-place operator by inserting
1195an 'i' in front of the name, e.g. __iadd__ implements in-place
1196__add__.
1197
1198Augmented assignment was implemented by Thomas Wouters.
1199
1200
1201List Comprehensions
1202-------------------
1203
1204This is a flexible new notation for lists whose elements are computed
1205from another list (or lists). The simplest form is:
1206
1207 [<expression> for <variable> in <sequence>]
1208
Guido van Rossum56db0952000-09-06 23:34:25 +00001209For example, [i**2 for i in range(4)] yields the list [0, 1, 4, 9].
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001210This is more efficient than a for loop with a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001211
1212You can also add a condition:
1213
1214 [<expression> for <variable> in <sequence> if <condition>]
1215
1216For example, [w for w in words if w == w.lower()] would yield the list
1217of words that contain no uppercase characters. This is more efficient
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001218than a for loop with an if statement and a list.append() call.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001219
1220You can also have nested for loops and more than one 'if' clause. For
1221example, here's a function that flattens a sequence of sequences::
1222
1223 def flatten(seq):
1224 return [x for subseq in seq for x in subseq]
1225
1226 flatten([[0], [1,2,3], [4,5], [6,7,8,9], []])
1227
1228This prints
1229
1230 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
1231
1232List comprehensions originated as a patch set from Greg Ewing; Skip
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001233Montanaro and Thomas Wouters also contributed. Described by PEP 202.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001234
1235
1236Extended Import Statement
1237-------------------------
1238
1239Many people have asked for a way to import a module under a different
1240name. This can be accomplished like this:
1241
1242 import foo
1243 bar = foo
1244 del foo
1245
1246but this common idiom gets old quickly. A simple extension of the
1247import statement now allows this to be written as follows:
1248
1249 import foo as bar
1250
1251There's also a variant for 'from ... import':
1252
1253 from foo import bar as spam
1254
1255This also works with packages; e.g. you can write this:
1256
1257 import test.regrtest as regrtest
1258
1259Note that 'as' is not a new keyword -- it is recognized only in this
1260context (this is only possible because the syntax for the import
1261statement doesn't involve expressions).
1262
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001263Implemented by Thomas Wouters. Described by PEP 221.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001264
1265
1266Extended Print Statement
1267------------------------
1268
1269Easily the most controversial new feature, this extension to the print
1270statement adds an option to make the output go to a different file
1271than the default sys.stdout.
1272
1273For example, to write an error message to sys.stderr, you can now
1274write:
1275
1276 print >> sys.stderr, "Error: bad dog!"
1277
1278As a special feature, if the expression used to indicate the file
Fred Drake45888ff2000-09-29 17:09:11 +00001279evaluates to None, the current value of sys.stdout is used. Thus:
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001280
1281 print >> None, "Hello world"
1282
1283is equivalent to
1284
1285 print "Hello world"
1286
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001287Design and implementation by Barry Warsaw. Described by PEP 214.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001288
1289
1290Optional Collection of Cyclical Garbage
1291---------------------------------------
1292
1293Python is now equipped with a garbage collector that can hunt down
1294cyclical references between Python objects. It's no replacement for
1295reference counting; in fact, it depends on the reference counts being
1296correct, and decides that a set of objects belong to a cycle if all
1297their reference counts can be accounted for from their references to
1298each other. This devious scheme was first proposed by Eric Tiedemann,
1299and brought to implementation by Neil Schemenauer.
1300
1301There's a module "gc" that lets you control some parameters of the
1302garbage collection. There's also an option to the configure script
1303that lets you enable or disable the garbage collection. In 2.0b1,
1304it's on by default, so that we (hopefully) can collect decent user
1305experience with this new feature. There are some questions about its
Fred Drake9f11cf82000-09-29 17:54:40 +00001306performance. If it proves to be too much of a problem, we'll turn it
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001307off by default in the final 2.0 release.
1308
1309
1310Smaller Changes
1311---------------
1312
1313A new function zip() was added. zip(seq1, seq2, ...) is equivalent to
1314map(None, seq1, seq2, ...) when the sequences have the same length;
1315i.e. zip([1,2,3], [10,20,30]) returns [(1,10), (2,20), (3,30)]. When
1316the lists are not all the same length, the shortest list wins:
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001317zip([1,2,3], [10,20]) returns [(1,10), (2,20)]. See PEP 201.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001318
1319sys.version_info is a tuple (major, minor, micro, level, serial).
1320
1321Dictionaries have an odd new method, setdefault(key, default).
1322dict.setdefault(key, default) returns dict[key] if it exists; if not,
1323it sets dict[key] to default and returns that value. Thus:
1324
1325 dict.setdefault(key, []).append(item)
1326
1327does the same work as this common idiom:
1328
1329 if not dict.has_key(key):
1330 dict[key] = []
1331 dict[key].append(item)
1332
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001333There are two new variants of SyntaxError that are raised for
1334indentation-related errors: IndentationError and TabError.
1335
1336Changed \x to consume exactly two hex digits; see PEP 223. Added \U
1337escape that consumes exactly eight hex digits.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001338
1339The limits on the size of expressions and file in Python source code
1340have been raised from 2**16 to 2**32. Previous versions of Python
1341were limited because the maximum argument size the Python VM accepted
1342was 2**16. This limited the size of object constructor expressions,
1343e.g. [1,2,3] or {'a':1, 'b':2}, and the size of source files. This
1344limit was raised thanks to a patch by Charles Waldman that effectively
1345fixes the problem. It is now much more likely that you will be
1346limited by available memory than by an arbitrary limit in Python.
1347
1348The interpreter's maximum recursion depth can be modified by Python
1349programs using sys.getrecursionlimit and sys.setrecursionlimit. This
1350limit is the maximum number of recursive calls that can be made by
1351Python code. The limit exists to prevent infinite recursion from
1352overflowing the C stack and causing a core dump. The default value is
13531000. The maximum safe value for a particular platform can be found
1354by running Misc/find_recursionlimit.py.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001355
1356New Modules and Packages
1357------------------------
1358
1359atexit - for registering functions to be called when Python exits.
1360
1361imputil - Greg Stein's alternative API for writing custom import
1362hooks.
1363
1364pyexpat - an interface to the Expat XML parser, contributed by Paul
1365Prescod.
1366
1367xml - a new package with XML support code organized (so far) in three
1368subpackages: xml.dom, xml.sax, and xml.parsers. Describing these
1369would fill a volume. There's a special feature whereby a
1370user-installed package named _xmlplus overrides the standard
1371xmlpackage; this is intended to give the XML SIG a hook to distribute
1372backwards-compatible updates to the standard xml package.
1373
1374webbrowser - a platform-independent API to launch a web browser.
1375
1376
Guido van Rossume905e952000-09-05 12:42:46 +00001377Changed Modules
1378---------------
1379
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001380array -- new methods for array objects: count, extend, index, pop, and
1381remove
1382
1383binascii -- new functions b2a_hex and a2b_hex that convert between
1384binary data and its hex representation
1385
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001386calendar -- Many new functions that support features including control
1387over which day of the week is the first day, returning strings instead
1388of printing them. Also new symbolic constants for days of week,
1389e.g. MONDAY, ..., SUNDAY.
1390
1391cgi -- FieldStorage objects have a getvalue method that works like a
1392dictionary's get method and returns the value attribute of the object.
1393
1394ConfigParser -- The parser object has new methods has_option,
1395remove_section, remove_option, set, and write. They allow the module
1396to be used for writing config files as well as reading them.
1397
1398ftplib -- ntransfercmd(), transfercmd(), and retrbinary() all now
Guido van Rossume905e952000-09-05 12:42:46 +00001399optionally support the RFC 959 REST command.
1400
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001401gzip -- readline and readlines now accept optional size arguments
Guido van Rossume905e952000-09-05 12:42:46 +00001402
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001403httplib -- New interfaces and support for HTTP/1.1 by Greg Stein. See
1404the module doc strings for details.
Guido van Rossum830ca2a2000-09-05 15:34:16 +00001405
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001406locale -- implement getdefaultlocale for Win32 and Macintosh
1407
1408marshal -- no longer dumps core when marshaling deeply nested or
1409recursive data structures
1410
1411os -- new functions isatty, seteuid, setegid, setreuid, setregid
1412
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001413os/popen2 -- popen2/popen3/popen4 support under Windows. popen2/popen3
1414support under Unix.
1415
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001416os/pty -- support for openpty and forkpty
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001417
1418os.path -- fix semantics of os.path.commonprefix
1419
1420smtplib -- support for sending very long messages
1421
1422socket -- new function getfqdn()
1423
1424readline -- new functions to read, write and truncate history files.
1425The readline section of the library reference manual contains an
1426example.
1427
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001428select -- add interface to poll system call
1429
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001430shutil -- new copyfileobj function
1431
1432SimpleHTTPServer, CGIHTTPServer -- Fix problems with buffering in the
1433HTTP server.
1434
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001435Tkinter -- optimization of function flatten
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001436
1437urllib -- scans environment variables for proxy configuration,
Tim Peters8b092332000-09-05 20:15:25 +00001438e.g. http_proxy.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001439
1440whichdb -- recognizes dumbdbm format
Guido van Rossume905e952000-09-05 12:42:46 +00001441
1442
1443Obsolete Modules
1444----------------
1445
1446None. However note that 1.6 made a whole slew of modules obsolete:
1447stdwin, soundex, cml, cmpcache, dircache, dump, find, grep, packmail,
1448poly, zmod, strop, util, whatsound.
1449
1450
1451Changed, New, Obsolete Tools
1452----------------------------
1453
Tim Peters8b092332000-09-05 20:15:25 +00001454None.
Guido van Rossume905e952000-09-05 12:42:46 +00001455
1456
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001457C-level Changes
1458---------------
1459
1460Several cleanup jobs were carried out throughout the source code.
1461
1462All C code was converted to ANSI C; we got rid of all uses of the
1463Py_PROTO() macro, which makes the header files a lot more readable.
1464
1465Most of the portability hacks were moved to a new header file,
1466pyport.h; several other new header files were added and some old
1467header files were removed, in an attempt to create a more rational set
1468of header files. (Few of these ever need to be included explicitly;
1469they are all included by Python.h.)
1470
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001471Trent Mick ensured portability to 64-bit platforms, under both Linux
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001472and Win64, especially for the new Intel Itanium processor. Mick also
1473added large file support for Linux64 and Win64.
Guido van Rossumf2ffce02000-09-05 04:38:34 +00001474
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001475The C APIs to return an object's size have been update to consistently
1476use the form PyXXX_Size, e.g. PySequence_Size and PyDict_Size. In
1477previous versions, the abstract interfaces used PyXXX_Length and the
1478concrete interfaces used PyXXX_Size. The old names,
1479e.g. PyObject_Length, are still available for backwards compatibility
1480at the API level, but are deprecated.
1481
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001482The PyOS_CheckStack function has been implemented on Windows by
1483Fredrik Lundh. It prevents Python from failing with a stack overflow
1484on Windows.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001485
1486The GC changes resulted in creation of two new slots on object,
1487tp_traverse and tp_clear. The augmented assignment changes result in
Guido van Rossum4338a282000-09-06 13:02:08 +00001488the creation of a new slot for each in-place operator.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001489
1490The GC API creates new requirements for container types implemented in
Guido van Rossum4338a282000-09-06 13:02:08 +00001491C extension modules. See Include/objimpl.h for details.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001492
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001493PyErr_Format has been updated to automatically calculate the size of
1494the buffer needed to hold the formatted result string. This change
1495prevents crashes caused by programmer error.
Jeremy Hyltonbdebd542000-09-05 18:28:54 +00001496
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001497New C API calls: PyObject_AsFileDescriptor, PyErr_WriteUnraisable.
Guido van Rossume905e952000-09-05 12:42:46 +00001498
Jeremy Hylton24c3d602000-09-05 19:36:26 +00001499PyRun_AnyFileEx, PyRun_SimpleFileEx, PyRun_FileEx -- New functions
1500that are the same as their non-Ex counterparts except they take an
1501extra flag argument that tells them to close the file when done.
1502
1503XXX There were other API changes that should be fleshed out here.
Guido van Rossumab9d6f01998-08-10 22:01:13 +00001504
Tim Peters8b092332000-09-05 20:15:25 +00001505
1506Windows Changes
1507---------------
1508
1509New popen2/popen3/peopen4 in os module (see Changed Modules above).
1510
1511os.popen is much more usable on Windows 95 and 98. See Microsoft
1512Knowledge Base article Q150956. The Win9x workaround described there
1513is implemented by the new w9xpopen.exe helper in the root of your
1514Python installation. Note that Python uses this internally; it is not
1515a standalone program.
1516
1517Administrator privileges are no longer required to install Python
1518on Windows NT or Windows 2000. If you have administrator privileges,
1519Python's registry info will be written under HKEY_LOCAL_MACHINE.
1520Otherwise the installer backs off to writing Python's registry info
Guido van Rossum4338a282000-09-06 13:02:08 +00001521under HKEY_CURRENT_USER. The latter is sufficient for all "normal"
Tim Peters8b092332000-09-05 20:15:25 +00001522uses of Python, but will prevent some advanced uses from working
1523(for example, running a Python script as an NT service, or possibly
1524from CGI).
1525
1526[This was new in 1.6] The installer no longer runs a separate Tcl/Tk
1527installer; instead, it installs the needed Tcl/Tk files directly in the
1528Python directory. If you already have a Tcl/Tk installation, this
1529wastes some disk space (about 4 Megs) but avoids problems with
1530conflicting Tcl/Tk installations, and makes it much easier for Python
1531to ensure that Tcl/Tk can find all its files.
1532
1533[This was new in 1.6] The Windows installer now installs by default in
1534\Python20\ on the default volume, instead of \Program Files\Python-2.0\.
1535
Guido van Rossumf62ed9c2000-09-26 11:16:10 +00001536
1537Updates to the changes between 1.5.2 and 1.6
1538--------------------------------------------
1539
1540The 1.6 NEWS file can't be changed after the release is done, so here
1541is some late-breaking news:
1542
1543New APIs in locale.py: normalize(), getdefaultlocale(), resetlocale(),
1544and changes to getlocale() and setlocale().
1545
1546The new module is now enabled per default.
1547
1548It is not true that the encodings codecs cannot be used for normal
1549strings: the string.encode() (which is also present on 8-bit strings
1550!) allows using them for 8-bit strings too, e.g. to convert files from
1551cp1252 (Windows) to latin-1 or vice-versa.
1552
1553Japanese codecs are available from Tamito KAJIYAMA:
1554http://pseudo.grad.sccs.chukyo-u.ac.jp/~kajiyama/python/
1555
1556
Guido van Rossumab9d6f01998-08-10 22:01:13 +00001557======================================================================