Keywords: whatsnew22

# 11 Other Changes and Fixes

As usual there were a bunch of other improvements and bugfixes scattered throughout the source tree. A search through the CVS change logs finds there were 527 patches applied and 683 bugs fixed between Python 2.1 and 2.2; 2.2.1 applied 139 patches and fixed 143 bugs; 2.2.2 applied 106 patches and fixed 82 bugs. These figures are likely to be underestimates.

Some of the more notable changes are:

- The code for the MacOS port for Python, maintained by Jack Jansen, is now kept in the main Python CVS tree, and many changes have been made to support MacOS X.

  The most significant change is the ability to build Python as a framework, enabled by supplying the --enable-framework option to the configure script when compiling Python. According to Jack Jansen, ``This installs a self-contained Python installation plus the OS X framework "glue" into /Library/Frameworks/Python.framework (or another location of choice). For now there is little immediate added benefit to this (actually, there is the disadvantage that you have to change your PATH to be able to find Python), but it is the basis for creating a full-blown Python application, porting the MacPython IDE, possibly using Python as a standard OSA scripting language and much more.''

  Most of the MacPython toolbox modules, which interface to MacOS APIs such as windowing, QuickTime, scripting, etc. have been ported to OS X, but they've been left commented out in setup.py. People who want to experiment with these modules can uncomment them manually.

- Keyword arguments passed to builtin functions that don't take them now cause a `TypeError` exception to be raised, with the message "function takes no keyword arguments".

- Weak references, added in Python 2.1 as an extension module, are now part of the core because they're used in the implementation of new-style classes. The `ReferenceError` exception has therefore moved from the `weakref` module to become a built-in exception.

- A new script, Tools/scripts/cleanfuture.py by Tim Peters, automatically removes obsolete `__future__` statements from Python source code.

- An additional flags argument has been added to the built-in function `compile()`, so the behaviour of `__future__` statements can now be correctly observed in simulated shells, such as those presented by IDLE and other development environments. This is described in PEP 264. (Contributed by Michael Hudson.)

- The new license introduced with Python 1.6 wasn't GPL-compatible. This is fixed by some minor textual changes to the 2.2 license, so it's now legal to embed Python inside a GPLed program again. Note that Python itself is not GPLed, but instead is under a license that's essentially equivalent to the BSD license, same as it always was. The license changes were also applied to the Python 2.0.1 and 2.1.1 releases.

- When presented with a Unicode filename on Windows, Python will now convert it to an MBCS encoded string, as used by the Microsoft file APIs. As MBCS is explicitly used by the file APIs, Python's choice of ASCII as the default encoding turns out to be an annoyance. On Unix, the locale's character set is used if `locale.nl_langinfo(CODESET)` is available. (Windows support was contributed by Mark Hammond with assistance from Marc-André Lemburg. Unix support was added by Martin von Löwis.)

- Large file support is now enabled on Windows. (Contributed by Tim Peters.)

- The Tools/scripts/ftpmirror.py script now parses a .netrc file, if you have one. (Contributed by Mike Romberg.)

- Some features of the object returned by the `xrange()` function are now deprecated, and trigger warnings when they're accessed; they'll disappear in Python 2.3. `xrange` objects tried to pretend they were full sequence types by supporting slicing, sequence multiplication, and the `in` operator, but these features were rarely used and therefore buggy. The `tolist()` method and the `start`, `stop`, and `step` attributes are also being deprecated. At the C level, the fourth argument to the `PyRange_New()` function, "`repeat`", has also been deprecated.

- There were a bunch of patches to the dictionary implementation, mostly to fix potential core dumps if a dictionary contains objects that sneakily changed their hash value, or mutated the dictionary they were contained in. For a while python-dev fell into a gentle rhythm of Michael Hudson finding a case that dumped core, Tim Peters fixing the bug, Michael finding another case, and round and round it went.

- On Windows, Python can now be compiled with Borland C thanks to a number of patches contributed by Stephen Hansen, though the result isn't fully functional yet. (But this is progress...)

- Another Windows enhancement: Wise Solutions generously offered PythonLabs use of their InstallerMaster 8.1 system. Earlier PythonLabs Windows installers used Wise 5.0a, which was beginning to show its age. (Packaged up by Tim Peters.)

- Files ending in "`.pyw`" can now be imported on Windows. "`.pyw`" is a Windows-only thing, used to indicate that a script needs to be run using PYTHONW.EXE instead of PYTHON.EXE in order to prevent a DOS console from popping up to display the output. This patch makes it possible to import such scripts, in case they're also usable as modules. (Implemented by David Bolen.)

- On platforms where Python uses the C `dlopen()` function to load extension modules, it's now possible to set the flags used by `dlopen()` using the `sys.getdlopenflags()` and `sys.setdlopenflags()` functions. (Contributed by Bram Stolk.)

- The `pow()` built-in function no longer supports 3 arguments when floating-point numbers are supplied. `pow(x, y, z)` returns `(x**y) % z`, but this is never useful for floating point numbers, and the final result varies unpredictably depending on the platform. A call such as `pow(2.0, 8.0, 7.0)` will now raise a `TypeError` exception.