Bump version to 0.9.1.

[python/dscho.git] / Misc / HISTORY

Python history
--------------

This file contains the release messages for previous Python releases.
As you read on you go back to the dark ages of Python's history.


======================================================================


From 1.5 to 1.5.1
=================

General
-------

- The documentation is now unbundled.  It has also been extensively
modified (mostly to implement a new and more uniform formatting
style).  We figure that most people will prefer to download one of the
preformatted documentation sets (HTML, PostScript or PDF) and that
only a minority have a need for the LaTeX or FrameMaker sources.  Of
course, the unbundled documentation sources still released -- just not
in the same archive file, and perhaps not on the same date.

- All bugs noted on the errors page (and many unnoted) are fixed.  All
new bugs take their places.

- No longer a core dump when attempting to print (or repr(), or str())
a list or dictionary that contains an instance of itself; instead, the
recursive entry is printed as [...] or {...}.  See Py_ReprEnter() and
Py_ReprLeave() below.  Comparisons of such objects still go beserk,
since this requires a different kind of fix; fortunately, this is a
less common scenario in practice.

Syntax change
-------------

- The raise statement can now be used without arguments, to re-raise 
a previously set exception.  This should be used after catching an
exception with an except clause only, either in the except clause or
later in the same function.

Import and module handling
--------------------------

- The implementation of import has changed to use a mutex (when
threading is supported).  This means that when two threads
simultaneously import the same module, the import statements are
serialized.  Recursive imports are not affected.

- Rewrote the finalization code almost completely, to be much more
careful with the order in which modules are destroyed.  Destructors
will now generally be able to reference built-in names such as None
without trouble.

- Case-insensitive platforms such as Mac and Windows require the case
of a module's filename to match the case of the module name as
specified in the import statement (see below).

- The code for figuring out the default path now distinguishes between
files, modules, executable files, and directories.  When expecting a
module, we also look for the .pyc or .pyo file.

Parser/tokenizer changes
------------------------

- The tokenizer can now warn you when your source code mixes tabs and
spaces for indentation in a manner that depends on how much a tab is
worth in spaces.  Use "python -t" or "python -v" to enable this
option.  Use "python -tt" to turn the warnings into errors.  (See also
tabnanny.py and tabpolice.py below.)

- Return unsigned characters from tok_nextc(), so '\377' isn't
mistaken for an EOF character.

- Fixed two pernicious bugs in the tokenizer that only affected AIX.
One was actually a general bug that was triggered by AIX's smaller I/O
buffer size.  The other was a bug in the AIX optimizer's loop
unrolling code; swapping two statements made the problem go away.

Tools, demos and miscellaneous files
------------------------------------

- There's a new version of Misc/python-mode.el (the Emacs mode for
Python) which is much smarter about guessing the indentation style
used in a particular file.  Lots of other cool features too!

- There are two new tools in Tools/scripts: tabnanny.py and
tabpolice.py, implementing two different ways of checking whether a
file uses indentation in a way that is sensitive to the interpretation
of a tab.  The preferred module is tabnanny.py (by Tim Peters).

- Some new demo programs:

        Demo/tkinter/guido/paint.py -- Dave Mitchell
        Demo/sockets/unixserver.py -- Piet van Oostrum
        

- Much better freeze support.  The freeze script can now freeze
hierarchical module names (with a corresponding change to import.c),
and has a few extra options (e.g. to suppress freezing specific
modules).  It also does much more on Windows NT.

- Version 1.0 of the faq wizard is included (only very small changes
since version 0.9.0).

- New feature for the ftpmirror script: when removing local files
(i.e., only when -r is used), do a recursive delete.

Configuring and building Python
-------------------------------

- Get rid of the check for -linet -- recent Sequent Dynix systems don't
need this any more and apparently it screws up their configuration.

- Some changes because gcc on SGI doesn't support '-all'.

- Changed the build rules to use $(LIBRARY) instead of
  -L.. -lpython$(VERSION)
since the latter trips up the SunOS 4.1.x linker (sigh).

- Fix the bug where the '# dgux is broken' comment in the Makefile
tripped over Make on some platforms.

- Changes for AIX: install the python.exp file; properly use
$(srcdir); the makexp_aix script now removes C++ entries of the form
Class::method.

- Deleted some Makefile targets only used by the (long obsolete)
gMakefile hacks.

Extension modules
-----------------

- Performance and threading improvements to the socket and bsddb
modules, by Christopher Lindblad of Infoseek.

- Added operator.__not__ and operator.not_.

- In the thread module, when a thread exits due to an unhandled
exception, don't store the exception information in sys.last_*; it
prevents proper calling of destructors of local variables.

- Fixed a number of small bugs in the cPickle module.

- Changed find() and rfind() in the strop module so that
find("x","",2) returns -1, matching the implementation in string.py.

- In the time module, be more careful with the result of ctime(), and
test for HAVE_MKTIME before usinmg mktime().

- Doc strings contributed by Mitch Chapman to the termios, pwd, gdbm
modules.

- Added the LOG_SYSLOG constant to the syslog module, if defined.

Standard library modules
------------------------

- All standard library modules have been converted to an indentation
style using either only tabs or only spaces -- never a mixture -- if
they weren't already consistent according to tabnanny.  This means
that the new -t option (see above) won't complain about standard
library modules.

- New standard library modules:

        threading -- GvR and the thread-sig
                Java style thread objects -- USE THIS!!!

        getpass -- Piers Lauder
                simple utilities to prompt for a password and to
                retrieve the current username

        imaplib -- Piers Lauder
                interface for the IMAP4 protocol

        poplib -- David Ascher, Piers Lauder
                interface for the POP3 protocol

        smtplib -- Dragon De Monsyne
                interface for the SMTP protocol

- Some obsolete modules moved to a separate directory (Lib/lib-old)
which is *not* in the default module search path:

        Para
        addpack
        codehack
        fmt
        lockfile
        newdir
        ni
        rand
        tb

- New version of the PCRE code (Perl Compatible Regular Expressions --
the re module and the supporting pcre extension) by Andrew Kuchling.
Incompatible new feature in re.sub(): the handling of escapes in the
replacement string has changed.

- Interface change in the copy module: a __deepcopy__ method is now
called with the memo dictionary as an argument.

- Feature change in the tokenize module: differentiate between NEWLINE
token (an official newline) and NL token (a newline that the grammar
ignores).

- Several bugfixes to the urllib module.  It is now truly thread-safe,
and several bugs and a portability problem have been fixed.  New
features, all due to Sjoerd Mullender: When creating a temporary file,
it gives it an appropriate suffix.  Support the "data:" URL scheme.
The open() method uses the tempcache.

- New version of the xmllib module (this time with a test suite!) by
Sjoerd Mullender.

- Added debugging code to the telnetlib module, to be able to trace
the actual traffic.

- In the rfc822 module, added support for deleting a header (still no
support for adding headers, though).  Also fixed a bug where an
illegal address would cause a crash in getrouteaddr(), fixed a
sign reversal in mktime_tz(), and use the local timezone by default
(the latter two due to Bill van Melle).

- The normpath() function in the dospath and ntpath modules no longer
does case normalization -- for that, use the separate function
normcase() (which always existed); normcase() has been sped up and
fixed (it was the cause of a crash in Mark Hammond's installer in
certain locales).

- New command supported by the ftplib module: rmd(); also fixed some
minor bugs.

- The profile module now uses a different timer function by default -- 
time.clock() is generally better than os.times().  This makes it work
better on Windows NT, too.

- The tempfile module now recovers when os.getcwd() raises an
exception.

- Fixed some bugs in the random module; gauss() was subtly wrong, and
vonmisesvariate() should return a full circle.  Courtesy Mike Miller,
Lambert Meertens (gauss()), and Magnus Kessler (vonmisesvariate()).

- Better default seed in the whrandom module, courtesy Andrew Kuchling.

- Fix slow close() in shelve module.

- The Unix mailbox class in the mailbox module is now more robust when
a line begins with the string "From " but is definitely not the start
of a new message.  The pattern used can be changed by overriding a
method or class variable.

- Added a rmtree() function to the copy module.

- Fixed several typos in the pickle module.  Also fixed problems when
unpickling in restricted execution environments.

- Added docstrings and fixed a typo in the py_compile and compileall
modules.  At Mark Hammond's repeated request, py_compile now append a
newline to the source if it needs one.  Both modules support an extra
parameter to specify the purported source filename (to be used in
error messages).

- Some performance tweaks by Jeremy Hylton to the gzip module.

- Fixed a bug in the merge order of dictionaries in the ConfigParser
module.  Courtesy Barry Warsaw.

- In the multifile module, support the optional second parameter to
seek() when possible.

- Several fixes to the gopherlib module by Lars Marius Garshol.  Also, 
urlparse now correctly handles Gopher URLs with query strings.

- Fixed a tiny bug in format_exception() in the traceback module.
Also rewrite tb_lineno() to be compatible with JPython (and not
disturb the current exception!); by Jim Hugunin.

- The httplib module is more robust when servers send a short response 
-- courtesy Tim O'Malley.

Tkinter and friends
-------------------

- Various typos and bugs fixed.

- New module Tkdnd implements a drag-and-drop protocol (within one
application only).

- The event_*() widget methods have been restructured slightly -- they
no longer use the default root.

- The interfaces for the bind*() and unbind() widget methods have been
redesigned; the bind*() methods now return the name of the Tcl command 
created for the callback, and this can be passed as a optional
argument to unbind() in order to delete the command (normally, such
commands are automatically unbound when the widget is destroyed, but
for some applications this isn't enough).

- Variable objects now have trace methods to interface to Tcl's
variable tracing facilities.

- Image objects now have an optional keyword argument, 'master', to
specify a widget (tree) to which they belong.  The image_names() and
image_types() calls are now also widget methods.

- There's a new global call, Tkinter.NoDefaultRoot(), which disables
all use of the default root by the Tkinter library.  This is useful to
debug applications that are in the process of being converted from
relying on the default root to explicit specification of the root
widget.

- The 'exit' command is deleted from the Tcl interpreter, since it
provided a loophole by which one could (accidentally) exit the Python
interpreter without invoking any cleanup code.

- Tcl_Finalize() is now registered as a Python low-level exit handle,
so Tcl will be finalized when Python exits.

The Python/C API
----------------

- New function PyThreadState_GetDict() returns a per-thread dictionary
intended for storing thread-local global variables.

- New functions Py_ReprEnter() and Py_ReprLeave() use the per-thread
dictionary to allow recursive container types to detect recursion in
their repr(), str() and print implementations.

- New function PyObject_Not(x) calculates (not x) according to Python's 
standard rules (basically, it negates the outcome PyObject_IsTrue(x).

- New function _PyModule_Clear(), which clears a module's dictionary
carefully without removing the __builtins__ entry.  This is implied
when a module object is deallocated (this used to clear the dictionary
completely).

- New function PyImport_ExecCodeModuleEx(), which extends
PyImport_ExecCodeModule() by adding an extra parameter to pass it the
true file.

- New functions Py_GetPythonHome() and Py_SetPythonHome(), intended to
allow embedded applications to force a different value for PYTHONHOME.

- New global flag Py_FrozenFlag is set when this is a "frozen" Python
binary; it suppresses warnings about not being able to find the
standard library directories.

- New global flag Py_TabcheckFlag is incremented by the -t option and
causes the tokenizer to issue warnings or errors about inconsistent
mixing of tabs and spaces for indentation.

Miscellaneous minor changes and bug fixes
-----------------------------------------

- Improved the error message when an attribute of an attribute-less
object is requested -- include the name of the attribute and the type
of the object in the message.

- Sped up int(), long(), float() a bit.

- Fixed a bug in list.sort() that would occasionally dump core.

- Fixed a bug in PyNumber_Power() that caused numeric arrays to fail
when taken tothe real power.

- Fixed a number of bugs in the file reading code, at least one of
which could cause a core dump on NT, and one of which would
occasionally cause file.read() to return less than the full contents
of the file.

- Performance hack by Vladimir Marangozov for stack frame creation.

- Make sure setvbuf() isn't used unless HAVE_SETVBUF is defined.

Windows 95/NT
-------------

- The .lib files are now part of the distribution; they are collected
in the subdirectory "libs" of the installation directory.

- The extension modules (.pyd files) are now collected in a separate
subdirectory of the installation directory named "DLLs".

- The case of a module's filename must now match the case of the
module name as specified in the import statement.  This is an
experimental feature -- if it turns out to break in too many
situations, it will be removed (or disabled by default) in the future.
It can be disabled on a per-case basis by setting the environment
variable PYTHONCASEOK (to any value).


======================================================================


From 1.5b2 to 1.5
=================

- Newly documentated module: BaseHTTPServer.py, thanks to Greg Stein.

- Added doc strings to string.py, stropmodule.c, structmodule.c,
thanks to Charles Waldman.

- Many nits fixed in the manuals, thanks to Fred Drake and many others
(especially Rob Hooft and Andrew Kuchling).  The HTML version now uses
HTML markup instead of inline GIF images for tables; only two images
are left (for obsure bits of math).  The index of the HTML version has
also been much improved.  Finally, it is once again possible to
generate an Emacs info file from the library manual (but I don't
commit to supporting this in future versions).

- New module: telnetlib.py (a simple telnet client library).

- New tool: Tools/versioncheck/, by Jack Jansen.

- Ported zlibmodule.c and bsddbmodule.c to NT; The project file for MS
DevStudio 5.0 now includes new subprojects to build the zlib and bsddb
extension modules.

- Many small changes again to Tkinter.py -- mostly bugfixes and adding
missing routines.  Thanks to Greg McFarlane for reporting a bunch of
problems and proofreading my fixes.

- The re module and its documentation are up to date with the latest
version released to the string-sig (Dec. 22).

- Stop test_grp.py from failing when the /etc/group file is empty
(yes, this happens!).

- Fix bug in integer conversion (mystrtoul.c) that caused
4294967296==0 to be true!

- The VC++ 4.2 project file should be complete again.

- In tempfile.py, use a better template on NT, and add a new optional
argument "suffix" with default "" to specify a specific extension for
the temporary filename (needed sometimes on NT but perhaps also handy
elsewhere).

- Fixed some bugs in the FAQ wizard, and converted it to use re
instead of regex.

- Fixed a mysteriously undetected error in dlmodule.c (it was using a
totally bogus routine name to raise an exception).

- Fixed bug in import.c which wasn't using the new "dos-8x3" name yet.

- Hopefully harmless changes to the build process to support shared
libraries on DG/UX.  This adds a target to create
libpython$(VERSION).so; however this target is *only* for DG/UX.

- Fixed a bug in the new format string error checking in getargs.c.

- A simple fix for infinite recursion when printing __builtins__:
reset '_' to None before printing and set it to the printed variable
*after* printing (and only when printing is successful).

- Fixed lib-tk/SimpleDialog.py to keep the dialog visible even if the
parent window is not (Skip Montanaro).

- Fixed the two most annoying problems with ftp URLs in
urllib.urlopen(); an empty file now correctly raises an error, and it
is no longer required to explicitly close the returned "file" object
before opening another ftp URL to the same host and directory.


======================================================================


From 1.5b1 to 1.5b2
===================

- Fixed a bug in cPickle.c that caused it to crash right away because
the version string had a different format.

- Changes in pickle.py and cPickle.c: when unpickling an instance of a
class that doesn't define the __getinitargs__() method, the __init__()
constructor is no longer called.  This makes a much larger group of
classes picklable by default, but may occasionally change semantics.
To force calling __init__() on unpickling, define a __getinitargs__()
method.  Other changes too, in particular cPickle now handles classes
defined in packages correctly.  The same change applies to copying
instances with copy.py.  The cPickle.c changes and some pickle.py
changes are courtesy Jim Fulton.

- Locale support in he "re" (Perl regular expressions) module.  Use 
the flag re.L (or re.LOCALE) to enable locale-specific matching
rules for \w and \b.  The in-line syntax for this flag is (?L).

- The built-in function isinstance(x, y) now also succeeds when y is
a type object and type(x) is y.

- repr() and str() of class and instance objects now reflect the
package/module in which the class is defined.

- Module "ni" has been removed.  (If you really need it, it's been
renamed to "ni1".  Let me know if this causes any problems for you.
Package authors are encouraged to write __init__.py files that
support both ni and 1.5 package support, so the same version can be
used with Python 1.4 as well as 1.5.)

- The thread module is now automatically included when threads are
configured.  (You must remove it from your existing Setup file,
since it is now in its own Setup.thread file.)

- New command line option "-x" to skip the first line of the script;
handy to make executable scripts on non-Unix platforms.

- In importdl.c, add the RTLD_GLOBAL to the dlopen() flags.  I
haven't checked how this affects things, but it should make symbols
in one shared library available to the next one.

- The Windows installer now installs in the "Program Files" folder on
the proper volume by default.

- The Windows configuration adds a new main program, "pythonw", and
registers a new extension, ".pyw" that invokes this.  This is a
pstandard Python interpreter that does not pop up a console window;
handy for pure Tkinter applications.  All output to the original
stdout and stderr is lost; reading from the original stdin yields
EOF.  Also, both python.exe and pythonw.exe now have a pretty icon
(a green snake in a box, courtesy Mark Hammond).

- Lots of improvements to emacs-mode.el again.  See Barry's web page:
http://www.python.org/ftp/emacs/pmdetails.html.

- Lots of improvements and additions to the library reference manual;
many by Fred Drake.

- Doc strings for the following modules: rfc822.py, posixpath.py,
ntpath.py, httplib.py.  Thanks to Mitch Chapman and Charles Waldman.

- Some more regression testing.

- An optional 4th (maxsplit) argument to strop.replace().

- Fixed handling of maxsplit in string.splitfields().

- Tweaked os.environ so it can be pickled and copied.

- The portability problems caused by indented preprocessor commands
and C++ style comments should be gone now.

- In random.py, added Pareto and Weibull distributions.

- The crypt module is now disabled in Modules/Setup.in by default; it
is rarely needed and causes errors on some systems where users often
don't know how to deal with those.

- Some improvements to the _tkinter build line suggested by Case Roole.

- A full suite of platform specific files for NetBSD 1.x, submitted by 
Anders Andersen.

- New Solaris specific header STROPTS.py.

- Moved a confusing occurrence of *shared* from the comments in
Modules/Setup.in (people would enable this one instead of the real
one, and get disappointing results).

- Changed the default mode for directories to be group-writable when
the installation process creates them.

- Check for pthread support in "-l_r" for FreeBSD/NetBSD, and support
shared libraries for both.

- Support FreeBSD and NetBSD in posixfile.py.

- Support for the "event" command, new in Tk 4.2.  By Case Roole.

- Add Tix_SafeInit() support to tkappinit.c.

- Various bugs fixed in "re.py" and "pcre.c".

- Fixed a bug (broken use of the syntax table) in the old "regexpr.c".

- In frozenmain.c, stdin is made unbuffered too when PYTHONUNBUFFERED
is set.

- Provide default blocksize for retrbinary in ftplib.py (Skip
Montanaro).

- In NT, pick the username up from different places in user.py (Jeff
Bauer).

- Patch to urlparse.urljoin() for ".." and "..#1", Marc Lemburg.

- Many small improvements to Jeff Rush' OS/2 support.

- ospath.py is gone; it's been obsolete for so many years now...

- The reference manual is now set up to prepare better HTML (still
using webmaker, alas).

- Add special handling to /Tools/freeze for Python modules that are
imported implicitly by the Python runtime: 'site' and 'exceptions'.

- Tools/faqwiz 0.8.3 -- add an option to suppress URL processing
inside <PRE>, by "Scott".

- Added ConfigParser.py, a generic parser for sectioned configuration
files.

- In _localemodule.c, LC_MESSAGES is not always defined; put it
between #ifdefs.

- Typo in resource.c: RUSAGE_CHILDERN -> RUSAGE_CHILDREN.

- Demo/scripts/newslist.py: Fix the way the version number is gotten
out of the RCS revision.

- PyArg_Parse[Tuple] now explicitly check for bad characters at the
end of the format string.

- Revamped PC/example_nt to support VC++ 5.x.

- <listobject>.sort() now uses a modified quicksort by Raymund Galvin,
after studying the GNU libg++ quicksort.  This should be much faster
if there are lots of duplicates, and otherwise at least as good.

- Added "uue" as an alias for "uuencode" to mimetools.py.  (Hm, the
uudecode bug where it complaints about trailing garbage is still there 
:-( ).

- pickle.py requires integers in text mode to be in decimal notation
(it used to accept octal and hex, even though it would only generate
decimal numbers).

- In string.atof(), don't fail when the "re" module is unavailable.
Plug the ensueing security leak by supplying an empty __builtins__
directory to eval().

- A bunch of small fixes and improvements to Tkinter.py.

- Fixed a buffer overrun in PC/getpathp.c.


======================================================================


From 1.5a4 to 1.5b1
===================

- The Windows NT/95 installer now includes full HTML of all manuals.
It also has a checkbox that lets you decide whether to install the
interpreter and library.  The WISE installer script for the installer
is included in the source tree as PC/python15.wse, and so are the
icons used for Python files.  The config.c file for the Windows build
is now complete with the pcre module.

- sys.ps1 and sys.ps2 can now arbitrary objects; their str() is
evaluated for the prompt.

- The reference manual is brought up to date (more or less -- it still
needs work, e.g. in the area of package import).

- The icons used by latex2html are now included in the Doc
subdirectory (mostly so that tarring up the HTML files can be fully
automated).  A simple index.html is also added to Doc (it only works
after you have successfully run latex2html).

- For all you would-be proselytizers out there: a new version of
Misc/BLURB describes Python more concisely, and Misc/comparisons
compares Python to several other languages.  Misc/BLURB.WINDOWS
contains a blurb specifically aimed at Windows programmers (by Mark
Hammond).

- A new version of the Python mode for Emacs is included as
Misc/python-mode.el.  There are too many new features to list here.
See http://www.python.org/ftp/emacs/pmdetails.html for more info.

- New module fileinput makes iterating over the lines of a list of
files easier.  (This still needs some more thinking to make it more
extensible.)

- There's full OS/2 support, courtesy Jeff Rush.  To build the OS/2
version, see PC/readme.txt and PC/os2vacpp.  This is for IBM's Visual
Age C++ compiler.  I expect that Jeff will also provide a binary
release for this platform.

- On Linux, the configure script now uses '-Xlinker -export-dynamic'
instead of '-rdynamic' to link the main program so that it exports its
symbols to shared libraries it loads dynamically.  I hope this doesn't
break on older Linux versions; it is needed for mklinux and appears to
work on Linux 2.0.30.

- Some Tkinter resstructuring: the geometry methods that apply to a
master are now properly usable on toplevel master widgets.  There's a
new (internal) widget class, BaseWidget.  New, longer "official" names
for the geometry manager methods have been added,
e.g. "grid_columnconfigure()" instead of "columnconfigure()".  The old
shorter names still work, and where there's ambiguity, pack wins over
place wins over grid.  Also, the bind_class method now returns its
value.

- New, RFC-822 conformant parsing of email addresses and address lists
in the rfc822 module, courtesy Ben Escoto.

- New, revamped tkappinit.c with support for popular packages (PIL,
TIX, BLT, TOGL).  For the last three, you need to execute the Tcl
command "load {} Tix" (or Blt, or Togl) to gain access to them.
The Modules/Setup line for the _tkinter module has been rewritten
using the cool line-breaking feature of most Bourne shells.

- New socket method connect_ex() returns the error code from connect()
instead of raising an exception on errors; this makes the logic
required for asynchronous connects simpler and more efficient.

- New "locale" module with (still experimental) interface to the
standard C library locale interface, courtesy Martin von Loewis.  This
does not repeat my mistake in 1.5a4 of always calling
setlocale(LC_ALL, "").  In fact, we've pretty much decided that
Python's standard numerical formatting operations should always use
the conventions for the C locale; the locale module contains utility
functions to format numbers according to the user specified locale.
(All this is accomplished by an explicit call to setlocale(LC_NUMERIC,
"C") after locale-changing calls.)  See the library manual. (Alas, the
promised changes to the "re" module for locale support have not been
materialized yet.  If you care, volunteer!)

- Memory leak plugged in Py_BuildValue when building a dictionary.

- Shared modules can now live inside packages (hierarchical module
namespaces).  No changes to the shared module itself are needed.

- Improved policy for __builtins__: this is a module in __main__ and a
dictionary everywhere else.

- Python no longer catches SIGHUP and SIGTERM by default.  This was
impossible to get right in the light of thread contexts.  If you want
your program to clean up when a signal happens, use the signal module
to set up your own signal handler.

- New Python/C API PyNumber_CoerceEx() does not return an exception
when no coercion is possible.  This is used to fix a problem where
comparing incompatible numbers for equality would raise an exception
rather than return false as in Python 1.4 -- it once again will return
false.

- The errno module is changed again -- the table of error messages
(errorstr) is removed.  Instead, you can use os.strerror().  This
removes redundance and a potential locale dependency.

- New module xmllib, to parse XML files.  By Sjoerd Mullender.

- New C API PyOS_AfterFork() is called after fork() in posixmodule.c.
It resets the signal module's notion of what the current process ID
and thread are, so that signal handlers will work after (and across)
calls to os.fork().

- Fixed most occurrences of fatal errors due to missing thread state.

- For vgrind (a flexible source pretty printer) fans, there's a simple
Python definition in Misc/vgrindefs, courtesy Neale Pickett.

- Fixed memory leak in exec statement.

- The test.pystone module has a new function, pystones(loops=LOOPS),
which returns a (benchtime, stones) tuple.  The main() function now
calls this and prints the report.

- Package directories now *require* the presence of an __init__.py (or
__init__.pyc) file before they are considered as packages.  This is
done to prevent accidental subdirectories with common names from
overriding modules with the same name.

- Fixed some strange exceptions in __del__ methods in library modules
(e.g. urllib).  This happens because the builtin names are already
deleted by the time __del__ is called.  The solution (a hack, but it
works) is to set some instance variables to 0 instead of None.

- The table of built-in module initializers is replaced by a pointer
variable.  This makes it possible to switch to a different table at
run time, e.g. when a collection of modules is loaded from a shared
library.  (No example code of how to do this is given, but it is
possible.)  The table is still there of course, its name prefixed with
an underscore and used to initialize the pointer.

- The warning about a thread still having a frame now only happens in
verbose mode.

- Change the signal finialization so that it also resets the signal
handlers.  After this has been called, our signal handlers are no
longer active!

- New version of tokenize.py (by Ka-Ping Yee) recognizes raw string
literals.  There's now also a test fort this module.

- The copy module now also uses __dict__.update(state) instead of
going through individual attribute assignments, for class instances
without a __setstate__ method.

- New module reconvert translates old-style (regex module) regular
expressions to new-style (re module, Perl-style) regular expressions.

- Most modules that used to use the regex module now use the re
module.  The grep module has a new pgrep() function which uses
Perl-style regular expressions.

- The (very old, backwards compatibility) regexp.py module has been
deleted.

- Restricted execution (rexec): added the pcre module (support for the
re module) to the list of trusted extension modules.

- New version of Jim Fulton's CObject object type, adds
PyCObject_FromVoidPtrAndDesc() and PyCObject_GetDesc() APIs.

- Some patches to Lee Busby's fpectl mods that accidentally didn't
make it into 1.5a4.

- In the string module, add an optional 4th argument to count(),
matching find() etc.

- Patch for the nntplib module by Charles Waldman to add optional user
and password arguments to NNTP.__init__(), for nntp servers that need
them.

- The str() function for class objects now returns
"modulename.classname" instead of returning the same as repr().

- The parsing of \xXX escapes no longer relies on sscanf().

- The "sharedmodules" subdirectory of the installation is renamed to
"lib-dynload".  (You may have to edit your Modules/Setup file to fix
this in an existing installation!)

- Fixed Don Beaudry's mess-up with the OPT test in the configure
script.  Certain SGI platforms will still issue a warning for each
compile; there's not much I can do about this since the compiler's
exit status doesn't indicate that I was using an obsolete option.

- Fixed Barry's mess-up with {}.get(), and added test cases for it.

- Shared libraries didn't quite work under AIX because of the change
in status of the GNU readline interface.  Fix due to by Vladimir
Marangozov.


======================================================================


From 1.5a3 to 1.5a4
===================

- faqwiz.py: version 0.8; Recognize https:// as URL; <html>...</html>
feature; better install instructions; removed faqmain.py (which was an
older version).

- nntplib.py: Fixed some bugs reported by Lars Wirzenius (to Debian)
about the treatment of lines starting with '.'.  Added a minimal test
function.

- struct module: ignore most whitespace in format strings.

- urllib.py: close the socket and temp file in URLopener.retrieve() so
that multiple retrievals using the same connection work.

- All standard exceptions are now classes by default; use -X to make
them strings (for backward compatibility only).

- There's a new standard exception hierarchy, defined in the standard
library module exceptions.py (which you never need to import
explicitly).  See
http://grail.cnri.reston.va.us/python/essays/stdexceptions.html for
more info.

- Three new C API functions:

  - int PyErr_GivenExceptionMatches(obj1, obj2)

    Returns 1 if obj1 and obj2 are the same object, or if obj1 is an
    instance of type obj2, or of a class derived from obj2

  - int PyErr_ExceptionMatches(obj)

    Higher level wrapper around PyErr_GivenExceptionMatches() which uses
    PyErr_Occurred() as obj1.  This will be the more commonly called
    function.

  - void PyErr_NormalizeException(typeptr, valptr, tbptr)

    Normalizes exceptions, and places the normalized values in the
    arguments.  If type is not a class, this does nothing.  If type is a
    class, then it makes sure that value is an instance of the class by:

    1. if instance is of the type, or a class derived from type, it does
       nothing.

    2. otherwise it instantiates the class, using the value as an
       argument.  If value is None, it uses an empty arg tuple, and if
       the value is a tuple, it uses just that.

- Another new C API function: PyErr_NewException() creates a new
exception class derived from Exception; when -X is given, it creates a
new string exception.

- core interpreter: remove the distinction between tuple and list
unpacking; allow an arbitrary sequence on the right hand side of any
unpack instruction.  (UNPACK_LIST and UNPACK_TUPLE now do the same
thing, which should really be called UNPACK_SEQUENCE.)

- classes: Allow assignments to an instance's __dict__ or __class__,
so you can change ivars (including shared ivars -- shock horror) and
change classes dynamically.  Also make the check on read-only
attributes of classes less draconic -- only the specials names
__dict__, __bases__, __name__ and __{get,set,del}attr__ can't be
assigned.

- Two new built-in functions: issubclass() and isinstance().  Both
take classes as their second arguments.  The former takes a class as
the first argument and returns true iff first is second, or is a
subclass of second.  The latter takes any object as the first argument
and returns true iff first is an instance of the second, or any
subclass of second.

- configure: Added configuration tests for presence of alarm(),
pause(), and getpwent().

- Doc/Makefile: changed latex2html targets.

- classes: Reverse the search order for the Don Beaudry hook so that
the first class with an applicable hook wins.  Makes more sense.

- Changed the checks made in Py_Initialize() and Py_Finalize().  It is
now legal to call these more than once.  The first call to
Py_Initialize() initializes, the first call to Py_Finalize()
finalizes.  There's also a new API, Py_IsInitalized() which checks
whether we are already initialized (in case you want to leave things
as they were).

- Completely disable the declarations for malloc(), realloc() and
free().  Any 90's C compiler has these in header files, and the tests
to decide whether to suppress the declarations kept failing on some
platforms.

- *Before* (instead of after) signalmodule.o is added, remove both
intrcheck.o and sigcheck.o.  This should get rid of warnings in ar or
ld on various systems.

- Added reop to PC/config.c

- configure: Decided to use -Aa -D_HPUX_SOURCE on HP-UX platforms.
Removed outdated HP-UX comments from README.  Added Cray T3E comments.

- Various renames of statically defined functions that had name
conflicts on some systems, e.g. strndup (GNU libc), join (Cray),
roundup (sys/types.h).

- urllib.py: Interpret three slashes in file: URL as local file (for
Netscape on Windows/Mac).

- copy.py: Make sure the objects returned by __getinitargs__() are
kept alive (in the memo) to avoid a certain kind of nasty crash.  (Not
easily reproducable because it requires a later call to
__getinitargs__() to return a tuple that happens to be allocated at
the same address.)

- Added definition of AR to toplevel Makefile.  Renamed @buildno temp
file to buildno1.

- Moved Include/assert.h to Parser/assert.h, which seems to be the
only place where it's needed.

- Tweaked the dictionary lookup code again for some more speed
(Vladimir Marangozov).

- NT build: Changed the way python15.lib is included in the other
projects.  Per Mark Hammond's suggestion, add it to the extra libs in
Settings instead of to the project's source files.

- regrtest.py: Change default verbosity so that there are only three
levels left: -q, default and -v.  In default mode, the name of each
test is now printed.  -v is the same as the old -vv.  -q is more quiet
than the old default mode.

- Removed the old FAQ from the distribution.  You now have to get it
from the web!

- Removed the PC/make_nt.in file from the distribution; it is no
longer needed.

- Changed the build sequence so that shared modules are built last.
This fixes things for AIX and doesn't hurt elsewhere.

- Improved test for GNU MP v1 in mpzmodule.c

- fileobject.c: ftell() on Linux discards all buffered data; changed
read() code to use lseek() instead to get the same effect

- configure.in, configure, importdl.c: NeXT sharedlib fixes

- tupleobject.c: PyTuple_SetItem asserts refcnt==1

- resource.c: Different strategy regarding whether to declare
getrusage() and getpagesize() -- #ifdef doesn't work, Linux has
conflicting decls in its headers.  Choice: only declare the return
type, not the argument prototype, and not on Linux.

- importdl.c, configure*: set sharedlib extensions properly for NeXT

- configure*, Makefile.in, Modules/Makefile.pre.in: AIX shared libraries
fixed; moved addition of PURIFY to LINKCC to configure

- reopmodule.c, regexmodule.c, regexpr.c, zlibmodule.c: needed casts
added to shup up various compilers.

- _tkinter.c: removed buggy mac #ifndef

- Doc: various Mac documentation changes, added docs for 'ic' module

- PC/make_nt.in: deleted

- test_time.py, test_strftime.py: tweaks to catch %Z (which may return
"")

- test_rotor.py: print b -> print `b`

- Tkinter.py: (tagOrId) -> (tagOrId,)

- Tkinter.py: the Tk class now also has a configure() method and
friends (they have been moved to the Misc class to accomplish this).

- dict.get(key[, default]) returns dict[key] if it exists, or default
if it doesn't.  The default defaults to None.  This is quicker for
some applications than using either has_key() or try:...except
KeyError:....

- Tools/webchecker/: some small changes to webchecker.py; added
websucker.py (a simple web site mirroring script).

- Dictionary objects now have a get() method (also in UserDict.py).
dict.get(key, default) returns dict[key] if it exists and default
otherwise; default defaults to None.

- Tools/scripts/logmerge.py: print the author, too.

- Changes to import: support for "import a.b.c" is now built in.  See
http://grail.cnri.reston.va.us/python/essays/packages.html
for more info.  Most important deviations from "ni.py": __init__.py is
executed in the package's namespace instead of as a submodule; and
there's no support for "__" or "__domain__".  Note that "ni.py" is not
changed to match this -- it is simply declared obsolete (while at the
same time, it is documented...:-( ).
Unfortunately, "ihooks.py" has not been upgraded (but see "knee.py"
for an example implementation of hierarchical module import written in
Python).

- More changes to import: the site.py module is now imported by
default when Python is initialized; use -S to disable it.  The site.py
module extends the path with several more directories: site-packages
inside the lib/python1.5/ directory, site-python in the lib/
directory, and pathnames mentioned in *.pth files found in either of
those directories.  See
http://grail.cnri.reston.va.us/python/essays/packages.html
for more info.

- Changes to standard library subdirectory names: those subdirectories
that are not packages have been renamed with a hypen in their name,
e.g. lib-tk, lib-stdwin, plat-win, plat-linux2, plat-sunos5, dos-8x3.
The test suite is now a package -- to run a test, you must now use
"import test.test_foo".

- A completely new re.py module is provided (thanks to Andrew
Kuchling, Tim Peters and Jeffrey Ollie) which uses Philip Hazel's
"pcre" re compiler and engine.  For a while, the "old" re.py (which
was new in 1.5a3!) will be kept around as re1.py.  The "old" regex
module and underlying parser and engine are still present -- while
regex is now officially obsolete, it will probably take several major
release cycles before it can be removed.

- The posix module now has a strerror() function which translates an
error code to a string.

- The emacs.py module (which was long obsolete) has been removed.

- The universal makefile Misc/Makefile.pre.in now features an
"install" target.  By default, installed shared libraries go into
$exec_prefix/lib/python$VERSION/site-packages/.

- The install-sh script is installed with the other configuration
specific files (in the config/ subdirectory).

- It turns out whatsound.py and sndhdr.py were identical modules.
Since there's also an imghdr.py file, I propose to make sndhdr.py the
official one.  For compatibility, whatsound.py imports * from
sndhdr.py.

- Class objects have a new attribute, __module__, giving the name of
the module in which they were declared.  This is useful for pickle and
for printing the full name of a class exception.

- Many extension modules no longer issue a fatal error when their
initialization fails; the importing code now checks whether an error
occurred during module initialization, and correctly propagates the
exception to the import statement.

- Most extension modules now raise class-based exceptions (except when
-X is used).

- Subtle changes to PyEval_{Save,Restore}Thread(): always swap the
thread state -- just don't manipulate the lock if it isn't there.

- Fixed a bug in Python/getopt.c that made it do the wrong thing when
an option was a single '-'.  Thanks to Andrew Kuchling.

- New module mimetypes.py will guess a MIME type from a filename's
extension.

- Windows: the DLL version is now settable via a resource rather than
being hardcoded.  This can be used for "branding" a binary Python
distribution.

- urllib.py is now threadsafe -- it now uses re instead of regex, and
sys.exc_info() instead of sys.exc_{type,value}.

- Many other library modules that used to use
sys.exc_{type,value,traceback} are now more thread-safe by virtue of
using sys.exc_info().

- The functions in popen2 have an optional buffer size parameter.
Also, the command argument can now be either a string (passed to the
shell) or a list of arguments (passed directly to execv).

- Alas, the thread support for _tkinter released with 1.5a3 didn't
work.  It's been rewritten.  The bad news is that it now requires a
modified version of a file in the standard Tcl distribution, which you
must compile with a -I option pointing to the standard Tcl source
tree.  For this reason, the thread support is disabled by default.

- The errno extension module adds two tables: errorcode maps errno
numbers to errno names (e.g. EINTR), and errorstr maps them to
message strings.  (The latter is redundant because the new call
posix.strerror() now does the same, but alla...)  (Marc-Andre Lemburg)

- The readline extension module now provides some interfaces to
internal readline routines that make it possible to write a completer
in Python.  An example completer, rlcompleter.py, is provided.

        When completing a simple identifier, it completes keywords,
        built-ins and globals in __main__; when completing
        NAME.NAME..., it evaluates (!) the expression up to the last
        dot and completes its attributes.

        It's very cool to do "import string" type "string.", hit the
        completion key (twice), and see the list of names defined by
        the string module!

        Tip: to use the tab key as the completion key, call

            readline.parse_and_bind("tab: complete")

- The traceback.py module has a new function tb_lineno() by Marc-Andre
Lemburg which extracts the line number from the linenumber table in
the code object.  Apparently the traceback object doesn't contains the
right linenumber when -O is used.  Rather than guessing whether -O is
on or off, the module itself uses tb_lineno() unconditionally.

- Fixed Demo/tkinter/matt/canvas-moving-or-creating.py: change bind()
to tag_bind() so it works again.

- The pystone script is now a standard library module.  Example use:
"import test.pystone; test.pystone.main()".

- The import of the readline module in interactive mode is now also
attempted when -i is specified.  (Yes, I know, giving in to Marc-Andre
Lemburg, who asked for this. :-)

- rfc822.py: Entirely rewritten parseaddr() function by Sjoerd
Mullender, to be closer to the standard.  This fixes the getaddr()
method.  Unfortunately, getaddrlist() is as broken as ever, since it
splits on commas without regard for RFC 822 quoting conventions.

- pprint.py: correctly emit trailing "," in singleton tuples.

- _tkinter.c: export names for its type objects, TkappType and
TkttType.

- pickle.py: use __module__ when defined; fix a particularly hard to
reproduce bug that confuses the memo when temporary objects are
returned by custom pickling interfaces; and a semantic change: when
unpickling the instance variables of an instance, use
inst.__dict__.update(value) instead of a for loop with setattr() over
the value.keys().  This is more consistent (the pickling doesn't use
getattr() either but pickles inst.__dict__) and avoids problems with
instances that have a __setattr__ hook.  But it *is* a semantic change
(because the setattr hook is no longer used).  So beware!

- config.h is now installed (at last) in
$exec_prefix/include/python1.5/.  For most sites, this means that it
is actually in $prefix/include/python1.5/, with all the other Python
include files, since $prefix and $exec_prefix are the same by
default.

- The imp module now supports parts of the functionality to implement
import of hierarchical module names.  It now supports find_module()
and load_module() for all types of modules.  Docstrings have been
added for those functions in the built-in imp module that are still
relevant (some old interfaces are obsolete).  For a sample
implementation of hierarchical module import in Python, see the new
library module knee.py.

- The % operator on string objects now allows arbitrary nested parens
in a %(...)X style format.  (Brad Howes)

- Reverse the order in which Setup and Setup.local are passed to the
makesetup script.  This allows variable definitions in Setup.local to
override definitions in Setup.  (But you'll still have to edit Setup
if you want to disable modules that are enabled by default, or if such
modules need non-standard options.)

- Added PyImport_ImportModuleEx(name, globals, locals, fromlist); this
is like PyImport_ImporModule(name) but receives the globals and locals
dict and the fromlist arguments as well.  (The name is a char*; the
others are PyObject*s).

- The 'p' format in the struct extension module alloded to above is
new in 1.5a4.

- The types.py module now uses try-except in a few places to make it
more likely that it can be imported in restricted mode.  Some type
names are undefined in that case, e.g. CodeType (inaccessible),
FileType (not always accessible), and TracebackType and FrameType
(inaccessible).

- In urllib.py: added separate administration of temporary files
created y URLopener.retrieve() so cleanup() can properly remove them.
The old code removed everything in tempcache which was a bad idea if
the user had passed a non-temp file into it.  Also, in basejoin(),
interpret relative paths starting in "../".  This is necessary if the
server uses symbolic links.

- The Windows build procedure and project files are now based on
Microsoft Visual C++ 5.x.  The build now takes place in the PCbuild
directory.  It is much more robust, and properly builds separate Debug
and Release versions.  (The installer will be added shortly.)

- Added casts and changed some return types in regexpr.c to avoid
compiler warnings or errors on some platforms.

- The AIX build tools for shared libraries now supports VPATH.  (Donn
Cave)

- By default, disable the "portable" multimedia modules audioop,
imageop, and rgbimg, since they don't work on 64-bit platforms.

- Fixed a nasty bug in cStringIO.c when code was actually using the
close() method (the destructors would try to free certain fields a
second time).

- For those who think they need it, there's a "user.py" module.  This
is *not* imported by default, but can be imported to run user-specific
setup commands, ~/.pythonrc.py.

- Various speedups suggested by Fredrik Lundh, Marc-Andre Lemburg,
Vladimir Marangozov, and others.

- Added os.altsep; this is '/' on DOS/Windows, and None on systems
with a sane filename syntax.

- os.py: Write out the dynamic OS choice, to avoid exec statements.
Adding support for a new OS is now a bit more work, but I bet that
'dos' or 'nt' will cover most situations...

- The obsolete exception AccessError is now really gone.

- Tools/faqwiz/: New installation instructions show how to maintain
multiple FAQs.  Removed bootstrap script from end of faqwiz.py module.
Added instructions to bootstrap script, too.  Version bumped to 0.8.1.
Added <html>...</html> feature suggested by Skip Montanaro.  Added
leading text for Roulette, default to 'Hit Reload ...'.  Fix typo in
default SRCDIR.

- Documentation for the relatively new modules "keyword" and "symbol"
has been added (to the end of the section on the parser extension
module).

- In module bisect.py, but functions have two optional argument 'lo'
and 'hi' which allow you to specify a subsequence of the array to
operate on.

- In ftplib.py, changed most methods to return their status (even when
it is always "200 OK") rather than swallowing it.

- main() now calls setlocale(LC_ALL, ""), if setlocale() and
<locale.h> are defined.

- Changes to configure.in, the configure script, and both
Makefile.pre.in files, to support SGI's SGI_ABI platform selection
environment variable.


======================================================================


From 1.4 to 1.5a3
=================

Security
--------

- If you are using the setuid script C wrapper (Misc/setuid-prog.c),
please use the new version.  The old version has a huge security leak.

Miscellaneous
-------------

- Because of various (small) incompatible changes in the Python
bytecode interpreter, the magic number for .pyc files has changed
again.

- The default module search path is now much saner.  Both on Unix and
Windows, it is essentially derived from the path to the executable
(which can be overridden by setting the environment variable
$PYTHONHOME).  The value of $PYTHONPATH on Windows is now inserted in
front of the default path, like in Unix (instead of overriding the
default path).  On Windows, the directory containing the executable is
added to the end of the path.

- A new version of python-mode.el for Emacs has been included.  Also,
a new file ccpy-style.el has been added to configure Emacs cc-mode for
the preferred style in Python C sources.

- On Unix, when using sys.argv[0] to insert the script directory in
front of sys.path, expand a symbolic link.  You can now install a
program in a private directory and have a symbolic link to it in a
public bin directory, and it will put the private directory in the
module search path.  Note that the symlink is expanded in sys.path[0]
but not in sys.argv[0], so you can still tell the name by which you
were invoked.

- It is now recommended to use ``#!/usr/bin/env python'' instead of
``#!/usr/local/bin/python'' at the start of executable scripts, except
for CGI scripts.  It has been determined that the use of /usr/bin/env
is more portable than that of /usr/local/bin/python -- scripts almost
never have to be edited when the Python interpreter lives in a
non-standard place.  Note that this doesn't work for CGI scripts since
the python executable often doesn't live in the HTTP server's default
search path.

- The silly -s command line option and the corresponding
PYTHONSUPPRESS environment variable (and the Py_SuppressPrint global
flag in the Python/C API) are gone.

- Most problems on 64-bit platforms should now be fixed.  Andrew
Kuchling helped.  Some uncommon extension modules are still not
clean (image and audio ops?).

- Fixed a bug where multiple anonymous tuple arguments would be mixed up
when using the debugger or profiler (reported by Just van Rossum).
The simplest example is ``def f((a,b),(c,d)): print a,b,c,d''; this
would print the wrong value when run under the debugger or profiler.

- The hacks that the dictionary implementation used to speed up
repeated lookups of the same C string were removed; these were a
source of subtle problems and don't seem to serve much of a purpose
any longer.

- All traces of support for the long dead access statement have been
removed from the sources.

- Plugged the two-byte memory leak in the tokenizer when reading an
interactive EOF.

- There's a -O option to the interpreter that removes SET_LINENO
instructions and assert statements (see below); it uses and produces
.pyo files instead of .pyc files.  The speedup is only a few percent
in most cases.  The line numbers are still available in the .pyo file,
as a separate table (which is also available in .pyc files).  However,
the removal of the SET_LINENO instructions means that the debugger
(pdb) can't set breakpoints on lines in -O mode.  The traceback module
contains a function to extract a line number from the code object
referenced in a traceback object.  In the future it should be possible
to write external bytecode optimizers that create better optimized
.pyo files, and there should be more control over optimization;
consider the -O option a "teaser".  Without -O, the assert statement
actually generates code that first checks __debug__; if this variable
is false, the assertion is not checked.  __debug__ is a built-in
variable whose value is initialized to track the -O flag (it's true
iff -O is not specified).  With -O, no code is generated for assert
statements, nor for code of the form ``if __debug__: <something>''.
Sorry, no further constant folding happens.


Performance
-----------

- It's much faster (almost twice for pystone.py -- see
Tools/scripts).  See the entry on string interning below.

- Some speedup by using separate free lists for method objects (both
the C and the Python variety) and for floating point numbers.

- Big speedup by allocating frame objects with a single malloc() call.
The Python/C API for frames is changed (you shouldn't be using this
anyway).

- Significant speedup by inlining some common opcodes for common operand 
types (e.g.  i+i, i-i, and list[i]).  Fredrik Lundh.

- Small speedup by reordering the method tables of some common
objects (e.g. list.append is now first).

- Big optimization to the read() method of file objects.  A read()
without arguments now attempts to use fstat to allocate a buffer of
the right size; for pipes and sockets, it will fall back to doubling
the buffer size.  While that the improvement is real on all systems,
it is most dramatic on Windows.


Documentation
-------------

- Many new pieces of library documentation were contributed, mostly by
Andrew Kuchling.  Even cmath is now documented!  There's also a
chapter of the library manual, "libundoc.tex", which provides a
listing of all undocumented modules, plus their status (e.g. internal,
obsolete, or in need of documentation).  Also contributions by Sue
Williams, Skip Montanaro, and some module authors who succumbed to
pressure to document their own contributed modules :-).  Note that
printing the documentation now kills fewer trees -- the margins have
been reduced.

- I have started documenting the Python/C API. Unfortunately this project 
hasn't been completed yet.  It will be complete before the final release of 
Python 1.5, though.  At the moment, it's better to read the LaTeX source 
than to attempt to run it through LaTeX and print the resulting dvi file.

- The posix module (and hence os.py) now has doc strings!  Thanks to Neil 
Schemenauer.  I received a few other contributions of doc strings.  In most 
other places, doc strings are still wishful thinking...


Language changes
----------------

- Private variables with leading double underscore are now a permanent 
feature of the language.  (These were experimental in release 1.4.  I have 
favorable experience using them; I can't label them "experimental" 
forever.)

- There's new string literal syntax for "raw strings".  Prefixing a string 
literal with the letter r (or R) disables all escape processing in the 
string; for example, r'\n' is a two-character string consisting of a 
backslash followed by the letter n.  This combines with all forms of string 
quotes; it is actually useful for triple quoted doc strings which might 
contain references to \n or \t.  An embedded quote prefixed with a 
backslash does not terminate the string, but the backslash is still 
included in the string; for example, r'\'' is a two-character string 
consisting of a backslash and a quote.  (Raw strings are also 
affectionately known as Robin strings, after their inventor, Robin 
Friedrich.)

- There's a simple assert statement, and a new exception
AssertionError.  For example, ``assert foo > 0'' is equivalent to ``if
not foo > 0: raise AssertionError''.  Sorry, the text of the asserted
condition is not available; it would be too complicated to generate
code for this (since the code is generated from a parse tree).
However, the text is displayed as part of the traceback!

- The raise statement has a new feature: when using "raise SomeClass,
somevalue" where somevalue is not an instance of SomeClass, it
instantiates SomeClass(somevalue).  In 1.5a4, if somevalue is an
instance of a *derived* class of SomeClass, the exception class raised
is set to somevalue.__class__, and SomeClass is ignored after that.

- Duplicate keyword arguments are now detected at compile time;
f(a=1,a=2) is now a syntax error.


Changes to builtin features
---------------------------

- There's a new exception FloatingPointError (used only by Lee Busby's
patches to catch floating point exceptions, at the moment).

- The obsolete exception ConflictError (presumably used by the long
obsolete access statement) has been deleted.

- There's a new function sys.exc_info() which returns the tuple 
(sys.exc_type, sys.exc_value, sys.exc_traceback) in a thread-safe way.

- There's a new variable sys.executable, pointing to the executable file 
for the Python interpreter.

- The sort() methods for lists no longer uses the C library qsort(); I
wrote my own quicksort implementation, with lots of help (in the form
of a kind of competition) from Tim Peters.  This solves a bug in
dictionary comparisons on some Solaris versions when Python is built
with threads, and makes sorting lists even faster.

- The semantics of comparing two dictionaries have changed, to make
comparison of unequal dictionaries faster.  A shorter dictionary is
always considered smaller than a larger dictionary.  For dictionaries
of the same size, the smallest differing element determines the
outcome (which yields the same results as before in this case, without
explicit sorting).  Thanks to Aaron Watters for suggesting something
like this.

- The semantics of try-except have changed subtly so that calling a
function in an exception handler that itself raises and catches an
exception no longer overwrites the sys.exc_* variables.  This also
alleviates the problem that objects referenced in a stack frame that
caught an exception are kept alive until another exception is caught
-- the sys.exc_* variables are restored to their previous value when
returning from a function that caught an exception.

- There's a new "buffer" interface.  Certain objects (e.g. strings and
arrays) now support the "buffer" protocol.  Buffer objects are acceptable 
whenever formerly a string was required for a write operation; mutable 
buffer objects can be the target of a read operation using the call
f.readinto(buffer).  A cool feature is that regular expression matching now 
also work on array objects.  Contribution by Jack Jansen.  (Needs 
documentation.)

- String interning: dictionary lookups are faster when the lookup
string object is the same object as the key in the dictionary, not
just a string with the same value.  This is done by having a pool of
"interned" strings.  Most names generated by the interpreter are now
automatically interned, and there's a new built-in function intern(s)
that returns the interned version of a string.  Interned strings are
not a different object type, and interning is totally optional, but by
interning most keys a speedup of about 15% was obtained for the
pystone benchmark.

- Dictionary objects have several new methods; clear() and copy() have
the obvious semantics, while update(d) merges the contents of another
dictionary d into this one, overriding existing keys.  The dictionary
implementation file is now called dictobject.c rather than the
confusing mappingobject.c.

- The intrinsic function dir() is much smarter; it looks in __dict__,
__members__ and __methods__.

- The intrinsic functions int(), long() and float() can now take a
string argument and then do the same thing as string.atoi(),
string.atol(), and string.atof().  No second 'base' argument is
allowed, and complex() does not take a string (nobody cared enough).

- When a module is deleted, its globals are now deleted in two phases.
In the first phase, all variables whose name begins with exactly one
underscore are replaced by None; in the second phase, all variables
are deleted.  This makes it possible to have global objects whose
destructors depend on other globals.  The deletion order within each
phase is still random.

- It is no longer an error for a function to be called without a
global variable __builtins__ -- an empty directory will be provided
by default.

- Guido's corollary to the "Don Beaudry hook": it is now possible to
do metaprogramming by using an instance as a base class.  Not for the
faint of heart; and undocumented as yet, but basically if a base class
is an instance, its class will be instantiated to create the new
class.  Jim Fulton will love it -- it also works with instances of his
"extension classes", since it is triggered by the presence of a
__class__ attribute on the purported base class.  See
Demo/metaclasses/index.html for an explanation and see that directory
for examples.

- Another change is that the Don Beaudry hook is now invoked when
*any* base class is special.  (Up to 1.5a3, the *last* special base
class is used; in 1.5a4, the more rational choice of the *first*
special base class is used.)

- New optional parameter to the readlines() method of file objects.
This indicates the number of bytes to read (the actual number of bytes
read will be somewhat larger due to buffering reading until the end of
the line).  Some optimizations have also been made to speed it up (but
not as much as read()).

- Complex numbers no longer have the ".conj" pseudo attribute; use
z.conjugate() instead, or complex(z.real, -z.imag).  Complex numbers
now *do* support the __members__ and __methods__ special attributes.

- The complex() function now looks for a __complex__() method on class
instances before giving up.

- Long integers now support arbitrary shift counts, so you can now
write 1L<<1000000, memory permitting.  (Python 1.4 reports "outrageous
shift count for this.)

- The hex() and oct() functions have been changed so that for regular
integers, they never emit a minus sign.  For example, on a 32-bit
machine, oct(-1) now returns '037777777777' and hex(-1) returns
'0xffffffff'.  While this may seem inconsistent, it is much more
useful.  (For long integers, a minus sign is used as before, to fit
the result in memory :-)

- The hash() function computes better hashes for several data types,
including strings, floating point numbers, and complex numbers.


New extension modules
---------------------

- New extension modules cStringIO.c and cPickle.c, written by Jim
Fulton and other folks at Digital Creations.  These are much more
efficient than their Python counterparts StringIO.py and pickle.py,
but don't support subclassing.  cPickle.c clocks up to 1000 times
faster than pickle.py; cStringIO.c's improvement is less dramatic but
still significant.

- New extension module zlibmodule.c, interfacing to the free zlib
library (gzip compatible compression).  There's also a module gzip.py
which provides a higher level interface.  Written by Andrew Kuchling
and Jeremy Hylton.

- New module readline; see the "miscellaneous" section above.

- New Unix extension module resource.c, by Jeremy Hylton, provides
access to getrlimit(), getrusage(), setrusage(), getpagesize(), and
related symbolic constants.

- New extension puremodule.c, by Barry Warsaw, which interfaces to the
Purify(TM) C API.  See also the file Misc/PURIFY.README.  It is also
possible to enable Purify by simply setting the PURIFY Makefile
variable in the Modules/Setup file.


Changes in extension modules
----------------------------

- The struct extension module has several new features to control byte
order and word size.  It supports reading and writing IEEE floats even
on platforms where this is not the native format.  It uses uppercase
format codes for unsigned integers of various sizes (always using
Python long ints for 'I' and 'L'), 's' with a size prefix for strings,
and 'p' for "Pascal strings" (with a leading length byte, included in
the size; blame Hannu Krosing; new in 1.5a4).  A prefix '>' forces
big-endian data and '<' forces little-endian data; these also select
standard data sizes and disable automatic alignment (use pad bytes as
needed).

- The array module supports uppercase format codes for unsigned data
formats (like the struct module).

- The fcntl extension module now exports the needed symbolic
constants.  (Formerly these were in FCNTL.py which was not available
or correct for all platforms.)

- The extension modules dbm, gdbm and bsddb now check that the
database is still open before making any new calls.

- The dbhash module is no more.  Use bsddb instead.  (There's a third
party interface for the BSD 2.x code somewhere on the web; support for
bsddb will be deprecated.)

- The gdbm module now supports a sync() method.

- The socket module now has some new functions: getprotobyname(), and
the set {ntoh,hton}{s,l}().

- Various modules now export their type object: socket.SocketType,
array.ArrayType.

- The socket module's accept() method now returns unknown addresses as
a tuple rather than raising an exception.  (This can happen in
promiscuous mode.)  Theres' also a new function getprotobyname().

- The pthread support for the thread module now works on most platforms.

- STDWIN is now officially obsolete.  Support for it will eventually
be removed from the distribution.

- The binascii extension module is now hopefully fully debugged.
(XXX Oops -- Fredrik Lundh promised me a uuencode fix that I never
received.)

- audioop.c: added a ratecv() function; better handling of overflow in
add().

- posixmodule.c: now exports the O_* flags (O_APPEND etc.).  On
Windows, also O_TEXT and O_BINARY.  The 'error' variable (the
exception is raises) is renamed -- its string value is now "os.error",
so newbies don't believe they have to import posix (or nt) to catch
it when they see os.error reported as posix.error.  The execve()
function now accepts any mapping object for the environment.

- A new version of the al (audio library) module for SGI was
contributed by Sjoerd Mullender.

- The regex module has a new function get_syntax() which retrieves the
syntax setting set by set_syntax().  The code was also sanitized,
removing worries about unclean error handling.  See also below for its
successor, re.py.

- The "new" module (which creates new objects of various types) once
again has a fully functioning new.function() method.  Dangerous as
ever!  Also, new.code() has several new arguments.

- A problem has been fixed in the rotor module: on systems with signed
characters, rotor-encoded data was not portable when the key contained
8-bit characters.  Also, setkey() now requires its argument rather
than having broken code to default it.

- The sys.builtin_module_names variable is now a tuple.  Another new
variables in sys is sys.executable (the full path to the Python
binary, if known).

- The specs for time.strftime() have undergone some revisions.  It
appears that not all format characters are supported in the same way
on all platforms.  Rather than reimplement it, we note these
differences in the documentation, and emphasize the shared set of
features.  There's also a thorough test set (that occasionally finds
problems in the C library implementation, e.g. on some Linuxes),
thanks to Skip Montanaro.

- The nis module seems broken when used with NIS+; unfortunately
nobody knows how to fix it.  It should still work with old NIS.


New library modules
-------------------

- New (still experimental) Perl-style regular expression module,
re.py, which uses a new interface for matching as well as a new
syntax; the new interface avoids the thread-unsafety of the regex
interface.  This comes with a helper extension reopmodule.c and vastly
rewritten regexpr.c.  Most work on this was done by Jeffrey Ollie, Tim
Peters, and Andrew Kuchling.  See the documentation libre.tex.  In
1.5, the old regex module is still fully supported; in the future, it
will become obsolete.

- New module gzip.py; see zlib above.

- New module keyword.py exports knowledge about Python's built-in
keywords.  (New version by Ka-Ping Yee.)

- New module pprint.py (with documentation) which supports
pretty-printing of lists, tuples, & dictionaries recursively.  By Fred
Drake.

- New module code.py.  The function code.compile_command() can
determine whether an interactively entered command is complete or not,
distinguishing incomplete from invalid input.  (XXX Unfortunately,
this seems broken at this moment, and I don't have the time to fix
it.  It's probably better to add an explicit interface to the parser
for this.)

- There is now a library module xdrlib.py which can read and write the
XDR data format as used by Sun RPC, for example.  It uses the struct
module.


Changes in library modules
--------------------------

- Module codehack.py is now completely obsolete.

- The pickle.py module has been updated to make it compatible with the
new binary format that cPickle.c produces.  By default it produces the
old all-ASCII format compatible with the old pickle.py, still much
faster than pickle.py; it will read both formats automatically.  A few
other updates have been made.

- A new helper module, copy_reg.py, is provided to register extensions
to the pickling code.

- Revamped module tokenize.py is much more accurate and has an
interface that makes it a breeze to write code to colorize Python
source code.  Contributed by Ka-Ping Yee.

- In ihooks.py, ModuleLoader.load_module() now closes the file under
all circumstances.

- The tempfile.py module has a new class, TemporaryFile, which creates
an open temporary file that will be deleted automatically when
closed.  This works on Windows and MacOS as well as on Unix.  (Jim
Fulton.)

- Changes to the cgi.py module: Most imports are now done at the
top of the module, which provides a speedup when using ni (Jim
Fulton).  The problem with file upload to a Windows platform is solved
by using the new tempfile.TemporaryFile class; temporary files are now
always opened in binary mode (Jim Fulton).  The cgi.escape() function
now takes an optional flag argument that quotes '"' to '&quot;'.  It
is now possible to invoke cgi.py from a command line script, to test
cgi scripts more easily outside an http server.  There's an optional
limit to the size of uploads to POST (Skip Montanaro).  Added a
'strict_parsing' option to all parsing functions (Jim Fulton).  The
function parse_qs() now uses urllib.unquote() on the name as well as
the value of fields (Clarence Gardner).  The FieldStorage class now
has a __len__() method.

- httplib.py: the socket object is no longer closed; all HTTP/1.*
responses are now accepted; and it is now thread-safe (by not using
the regex module).

- BaseHTTPModule.py: treat all HTTP/1.* versions the same.

- The popen2.py module is now rewritten using a class, which makes
access to the standard error stream and the process id of the
subprocess possible.

- Added timezone support to the rfc822.py module, in the form of a
getdate_tz() method and a parsedate_tz() function; also a mktime_tz().
Also added recognition of some non-standard date formats, by Lars
Wirzenius, and RFC 850 dates (Chris Lawrence).

- mhlib.py: various enhancements, including almost compatible parsing
of message sequence specifiers without invoking a subprocess.  Also
added a createmessage() method by Lars Wirzenius.

- The StringIO.StringIO class now supports readline(nbytes).  (Lars 
Wirzenius.)  (Of course, you should be using cStringIO for performance.)

- UserDict.py supports the new dictionary methods as well.

- Improvements for whrandom.py by Tim Peters: use 32-bit arithmetic to
speed it up, and replace 0 seed values by 1 to avoid degeneration.
A bug was fixed in the test for invalid arguments.

- Module ftplib.py: added support for parsing a .netrc file (Fred
Drake).  Also added an ntransfercmd() method to the FTP class, which
allows access to the expected size of a transfer when available, and a
parse150() function to the module which parses the corresponding 150
response.

- urllib.py: the ftp cache is now limited to 10 entries.  Added
quote_plus() and unquote_plus() functions which are like quote() and
unquote() but also replace spaces with '+' or vice versa, for
encoding/decoding CGI form arguments.  Catch all errors from the ftp
module.  HTTP requests now add the Host: header line.  The proxy
variable names are now mapped to lower case, for Windows.  The
spliturl() function no longer erroneously throws away all data past
the first newline.  The basejoin() function now intereprets "../"
correctly.  I *believe* that the problems with "exception raised in
__del__" under certain circumstances have been fixed (mostly by
changes elsewher in the interpreter).

- In urlparse.py, there is a cache for results in urlparse.urlparse();
its size limit is set to 20.  Also, new URL schemes shttp, https, and
snews are "supported".

- shelve.py: use cPickle and cStringIO when available.  Also added
a sync() method, which calls the database's sync() method if there is
one.

- The mimetools.py module now uses the available Python modules for
decoding quoted-printable, uuencode and base64 formats, rather than
creating a subprocess.

- The python debugger (pdb.py, and its base class bdb.py) now support
conditional breakpoints.  See the docs.

- The modules base64.py, uu.py and quopri.py can now be used as simple
command line utilities.

- Various small fixes to the nntplib.py module that I can't bother to
document in detail.

- Sjoerd Mullender's mimify.py module now supports base64 encoding and 
includes functions to handle the funny encoding you sometimes see in mail 
headers.  It is now documented.

- mailbox.py: Added BabylMailbox.  Improved the way the mailbox is
gotten from the environment.

- Many more modules now correctly open files in binary mode when this
is necessary on non-Unix platforms.

- The copying functions in the undocumented module shutil.py are
smarter.

- The Writer classes in the formatter.py module now have a flush()
method.

- The sgmllib.py module accepts hyphens and periods in the middle of
attribute names.  While this is against the SGML standard, there is
some HTML out there that uses this...

- The interface for the Python bytecode disassembler module, dis.py,
has been enhanced quite a bit.  There's now one main function,
dis.dis(), which takes almost any kind of object (function, module,
class, instance, method, code object) and disassembles it; without
arguments it disassembles the last frame of the last traceback.  The
other functions have changed slightly, too.

- The imghdr.py module recognizes new image types: BMP, PNG.

- The string.py module has a new function replace(str, old, new,
[maxsplit]) which does substring replacements.  It is actually
implemented in C in the strop module.  The functions [r]find() an
[r]index() have an optional 4th argument indicating the end of the
substring to search, alsoo implemented by their strop counterparts.
(Remember, never import strop -- import string uses strop when
available with zero overhead.)

- The string.join() function now accepts any sequence argument, not
just lists and tuples.

- The string.maketrans() requires its first two arguments to be
present.  The old version didn't require them, but there's not much
point without them, and the documentation suggests that they are
required, so we fixed the code to match the documentation.

- The regsub.py module has a function clear_cache(), which clears its
internal cache of compiled regular expressions.  Also, the cache now
takes the current syntax setting into account.  (However, this module
is now obsolete -- use the sub() or subn() functions or methods in the
re module.)

- The undocumented module Complex.py has been removed, now that Python
has built-in complex numbers.  A similar module remains as
Demo/classes/Complex.py, as an example.


Changes to the build process
----------------------------

- The way GNU readline is configured is totally different.  The
--with-readline configure option is gone.  It is now an extension
module, which may be loaded dynamically.  You must enable it (and
specify the correct linraries to link with) in the Modules/Setup file.
Importing the module installs some hooks which enable command line
editing.  When the interpreter shell is invoked interactively, it
attempts to import the readline module; when this fails, the default
input mechanism is used.  The hook variables are PyOS_InputHook and
PyOS_ReadlineFunctionPointer.  (Code contributed by Lee Busby, with
ideas from William Magro.)

- New build procedure: a single library, libpython1.5.a, is now built,
which contains absolutely everything except for a one-line main()
program (which calls Py_Main(argc, argv) to start the interpreter
shell).  This makes life much simpler for applications that need to
embed Python.  The serial number of the build is now included in the
version string (sys.version).

- As far as I can tell, neither gcc -Wall nor the Microsoft compiler
emits a single warning any more when compiling Python.

- A number of new Makefile variables have been added for special
situations, e.g. LDLAST is appended to the link command.  These are
used by editing the Makefile or passing them on the make command
line.

- A set of patches from Lee Busby has been integrated that make it
possible to catch floating point exceptions.  Use the configure option
--with-fpectl to enable the patches; the extension modules fpectl and
fpetest provide control to enable/disable and test the feature,
respectively.

- The support for shared libraries under AIX is now simpler and more
robust.  Thanks to Vladimir Marangozov for revamping his own patches!

- The Modules/makesetup script now reads a file Setup.local as well as
a file Setup.  Most changes to the Setup script can be done by editing
Setup.local instead, which makes it easier to carry a particular setup
over from one release to the next.

- The Modules/makesetup script now copies any "include" lines it
encounters verbatim into the output Makefile.  It also recognizes .cxx
and .cpp as C++ source files.

- The configure script is smarter about C compiler options; e.g. with
gcc it uses -O2 and -g when possible, and on some other platforms it
uses -Olimit 1500 to avoid a warning from the optimizer about the main
loop in ceval.c (which has more than 1000 basic blocks).

- The configure script now detects whether malloc(0) returns a NULL
pointer or a valid block (of length zero).  This avoids the nonsense
of always adding one byte to all malloc() arguments on most platforms.

- The configure script has a new option, --with-dec-threads, to enable
DEC threads on DEC Alpha platforms.  Also, --with-threads is now an
alias for --with-thread (this was the Most Common Typo in configure
arguments).

- Many changes in Doc/Makefile; amongst others, latex2html is now used
to generate HTML from all latex documents.


Change to the Python/C API
--------------------------

- Because some interfaces have changed, the PYTHON_API macro has been
bumped.  Most extensions built for the old API version will still run,
but I can't guarantee this.  Python prints a warning message on
version mismatches; it dumps core when the version mismatch causes a
serious problem :-)

- I've completed the Grand Renaming, with the help of Roger Masse and
Barry Warsaw.  This makes reading or debugging the code much easier.
Many other unrelated code reorganizations have also been carried out.
The allobjects.h header file is gone; instead, you would have to
include Python.h followed by rename2.h.  But you're better off running
Tools/scripts/fixcid.py -s Misc/RENAME on your source, so you can omit
the rename2.h; it will disappear in the next release.

- Various and sundry small bugs in the "abstract" interfaces have been
fixed.  Thanks to all the (involuntary) testers of the Python 1.4
version!  Some new functions have been added, e.g. PySequence_List(o),
equivalent to list(o) in Python.

- New API functions PyLong_FromUnsignedLong() and
PyLong_AsUnsignedLong().

- The API functions in the file cgensupport.c are no longer
supported.  This file has been moved to Modules and is only ever
compiled when the SGI specific 'gl' module is built.

- PyObject_Compare() can now raise an exception.  Check with
PyErr_Occurred().  The comparison function in an object type may also
raise an exception.

- The slice interface uses an upper bound of INT_MAX when no explicit
upper bound is given (e.x. for a[1:]).  It used to ask the object for
its length and do the calculations.

- Support for multiple independent interpreters.  See Doc/api.tex,
functions Py_NewInterpreter() and Py_EndInterpreter().  Since the
documentation is incomplete, also see the new Demo/pysvr example
(which shows how to use these in a threaded application) and the
source code.

- There is now a Py_Finalize() function which "de-initializes"
Python.  It is possible to completely restart the interpreter
repeatedly by calling Py_Finalize() followed by Py_Initialize().  A
change of functionality in Py_Initialize() means that it is now a
fatal error to call it while the interpreter is already initialized.
The old, half-hearted Py_Cleanup() routine is gone.  Use of Py_Exit()
is deprecated (it is nothing more than Py_Finalize() followed by
exit()).

- There are no known memory leaks left.  While Py_Finalize() doesn't
free *all* allocated memory (some of it is hard to track down),
repeated calls to Py_Finalize() and Py_Initialize() do not create
unaccessible heap blocks.

- There is now explicit per-thread state.  (Inspired by, but not the
same as, Greg Stein's free threading patches.)

- There is now better support for threading C applications.  There are
now explicit APIs to manipulate the interpreter lock.  Read the source
or the Demo/pysvr example; the new functions are
PyEval_{Acquire,Release}{Lock,Thread}().

- The test macro DEBUG has changed to Py_DEBUG, to avoid interference
with other libraries' DEBUG macros.  Likewise for any other test
macros that didn't yet start with Py_.

- New wrappers around malloc() and friends: Py_Malloc() etc. call
malloc() and call PyErr_NoMemory() when it fails; PyMem_Malloc() call
just malloc().  Use of these wrappers could be essential if multiple
memory allocators exist (e.g. when using certain DLL setups under
Windows).  (Idea by Jim Fulton.)

- New C API PyImport_Import() which uses whatever __import__() hook
that is installed for the current execution environment.  By Jim
Fulton.

- It is now possible for an extension module's init function to fail
non-fatally, by calling one of the PyErr_* functions and returning.

- The PyInt_AS_LONG() and PyFloat_AS_DOUBLE() macros now cast their
argument to the proper type, like the similar PyString macros already
did.  (Suggestion by Marc-Andre Lemburg.)  Similar for PyList_GET_SIZE
and PyList_GET_ITEM.

- Some of the Py_Get* function, like Py_GetVersion() (but not yet
Py_GetPath()) are now declared as returning a const char *.  (More
should follow.)

- Changed the run-time library to check for exceptions after object
comparisons.  PyObject_Compare() can now return an exception; use
PyErr_Occurred() to check (there is *no* special return value).

- PyFile_WriteString() and Py_Flushline() now return error indicators
instead of clearing exceptions.  This fixes an obscure bug where using
these would clear a pending exception, discovered by Just van Rossum.

- There's a new function, PyArg_ParseTupleAndKeywords(), which parses
an argument list including keyword arguments.  Contributed by Geoff
Philbrick.

- PyArg_GetInt() is gone.

- It's no longer necessary to include graminit.h when calling one of
the extended parser API functions.  The three public grammar start
symbols are now in Python.h as Py_single_input, Py_file_input, and
Py_eval_input.

- The CObject interface has a new function,
PyCObject_Import(module, name).  It calls PyCObject_AsVoidPtr()
on the object referenced by "module.name".


Tkinter
-------

- On popular demand, _tkinter once again installs a hook for readline
that processes certain Tk events while waiting for the user to type
(using PyOS_InputHook).

- A patch by Craig McPheeters plugs the most obnoxious memory leaks,
caused by command definitions referencing widget objects beyond their
lifetime.

- New standard dialog modules: tkColorChooser.py, tkCommonDialog.py,
tkMessageBox.py, tkFileDialog.py, tkSimpleDialog.py These interface
with the new Tk dialog scripts, and provide more "native platform"
style file selection dialog boxes on some platforms.  Contributed by
Fredrik Lundh.

- Tkinter.py: when the first Tk object is destroyed, it sets the
hiddel global _default_root to None, so that when another Tk object is
created it becomes the new default root.  Other miscellaneous
changes and fixes.

- The Image class now has a configure method.

- Added a bunch of new winfo options to Tkinter.py; we should now be
up to date with Tk 4.2.  The new winfo options supported are:
mananger, pointerx, pointerxy, pointery, server, viewable, visualid,
visualsavailable.

- The broken bind() method on Canvas objects defined in the Canvas.py
module has been fixed.  The CanvasItem and Group classes now also have
an unbind() method.

- The problem with Tkinter.py falling back to trying to import
"tkinter" when "_tkinter" is not found has been fixed -- it no longer
tries "tkinter", ever.  This makes diagnosing the problem "_tkinter
not configured" much easier and will hopefully reduce the newsgroup
traffic on this topic.

- The ScrolledText module once again supports the 'cnf' parameter, to
be compatible with the examples in Mark Lutz' book (I know, I know,
too late...)

- The _tkinter.c extension module has been revamped.  It now support
Tk versions 4.1 through 8.0; support for 4.0 has been dropped.  It
works well under Windows and Mac (with the latest Tk ports to those
platforms).  It also supports threading -- it is safe for one
(Python-created) thread to be blocked in _tkinter.mainloop() while
other threads modify widgets.  To make the changes visible, those
threads must use update_idletasks()method.  (The patch for threading
in 1.5a3 was broken; in 1.5a4, it is back in a different version,
which requires access to the Tcl sources to get it to work -- hence it
is disabled by default.)

- A bug in _tkinter.c has been fixed, where Split() with a string
containing an unmatched '"' could cause an exception or core dump.

- Unfortunately, on Windows and Mac, Tk 8.0 no longer supports
CreateFileHandler, so _tkinter.createfilehandler is not available on
those platforms when using Tk 8.0 or later.  I will have to rethink
how to interface with Tcl's lower-level event mechanism, or with its
channels (which are like Python's file-like objects).  Jack Jansen has
provided a fix for the Mac, so createfilehandler *is* actually
supported there; maybe I can adapt his fix for Windows.


Tools and Demos
---------------

- A new regression test suite is provided, which tests most of the
standard and built-in modules.  The regression test is run by invoking
the script Lib/test/regrtest.py.  Barry Warsaw wrote the test harnass;
he and Roger Masse contributed most of the new tests.

- New tool: faqwiz -- the CGI script that is used to maintain the
Python FAQ (http://grail.cnri.reston.va.us/cgi-bin/faqw.py).  In
Tools/faqwiz.

- New tool: webchecker -- a simple extensible web robot that, when
aimed at a web server, checks that server for dead links.  Available
are a command line utility as well as a Tkinter based GUI version.  In
Tools/webchecker.  A simplified version of this program is dissected
in my article in O'Reilly's WWW Journal, the issue on Scripting
Languages (Vol 2, No 2); Scripting the Web with Python (pp 97-120).
Includes a parser for robots.txt files by Skip Montanaro.

- New small tools: cvsfiles.py (prints a list of all files under CVS
n a particular directory tree), treesync.py (a rather Guido-specific
script to synchronize two source trees, one on Windows NT, the other
one on Unix under CVS but accessible from the NT box), and logmerge.py
(sort a collection of RCS or CVS logs by date).  In Tools/scripts.

- The freeze script now also works under Windows (NT).  Another
feature allows the -p option to be pointed at the Python source tree
instead of the installation prefix.  This was loosely based on part of
xfreeze by Sam Rushing and Bill Tutt.

- New examples (Demo/extend) that show how to use the generic
extension makefile (Misc/Makefile.pre.in).

- Tools/scripts/h2py.py now supports C++ comments.

- Tools/scripts/pystone.py script is upgraded to version 1.1; there
was a bug in version 1.0 (distributed with Python 1.4) that leaked
memory.  Also, in 1.1, the LOOPS variable is incremented to 10000.

- Demo/classes/Rat.py completely rewritten by Sjoerd Mullender.


Windows (NT and 95)
-------------------

- New project files for Developer Studio (Visual C++) 5.0 for Windows
NT (the old VC++ 4.2 Makefile is also still supported, but will
eventually be withdrawn due to its bulkiness).

- See the note on the new module search path in the "Miscellaneous" section 
above.

- Support for Win32s (the 32-bit Windows API under Windows 3.1) is
basically withdrawn.  If it still works for you, you're lucky.

- There's a new extension module, msvcrt.c, which provides various 
low-level operations defined in the Microsoft Visual C++ Runtime Library.  
These include locking(), setmode(), get_osfhandle(), set_osfhandle(), and 
console I/O functions like kbhit(), getch() and putch().

- The -u option not only sets the standard I/O streams to unbuffered
status, but also sets them in binary mode.  (This can also be done
using msvcrt.setmode(), by the way.)

- The, sys.prefix and sys.exec_prefix variables point to the directory 
where Python is installed, or to the top of the source tree, if it was run 
from there.

- The various os.path modules (posixpath, ntpath, macpath) now support
passing more than two arguments to the join() function, so
os.path.join(a, b, c) is the same as os.path.join(a, os.path.join(b,
c)).

- The ntpath module (normally used as os.path) supports ~ to $HOME 
expansion in expanduser().

- The freeze tool now works on Windows.

- See also the Tkinter category for a sad note on
_tkinter.createfilehandler().

- The truncate() method for file objects now works on Windows.

- Py_Initialize() is no longer called when the DLL is loaded.  You
must call it yourself.

- The time module's clock() function now has good precision through
the use of the Win32 API QueryPerformanceCounter().

- Mark Hammond will release Python 1.5 versions of PythonWin and his
other Windows specific code: the win32api extensions, COM/ActiveX
support, and the MFC interface.


Mac
---

- As always, the Macintosh port will be done by Jack Jansen.  He will
make a separate announcement for the Mac specific source code and the
binary distribution(s) when these are ready.


======================================================================


=====================================
==> Release 1.4 (October 25 1996) <==
=====================================

(Starting in reverse chronological order:)

- Changed disclaimer notice.

- Added SHELL=/bin/sh to Misc/Makefile.pre.in -- some Make versions
default to the user's login shell.

- In Lib/tkinter/Tkinter.py, removed bogus binding of <Delete> in Text
widget, and bogus bspace() function.

- In Lib/cgi.py, bumped __version__ to 2.0 and restored a truncated
paragraph.

- Fixed the NT Makefile (PC/vc40.mak) for VC 4.0 to set /MD for all
subprojects, and to remove the (broken) experimental NumPy
subprojects.

- In Lib/py_compile.py, cast mtime to long() so it will work on Mac
(where os.stat() returns mtimes as floats.)
- Set self.rfile unbuffered (like self.wfile) in SocketServer.py, to
fix POST in CGIHTTPServer.py.

- Version 2.83 of Misc/python-mode.el for Emacs is included.

- In Modules/regexmodule.c, fixed symcomp() to correctly handle a new
group starting immediately after a group tag.

- In Lib/SocketServer.py, changed the mode for rfile to unbuffered.

- In Objects/stringobject.c, fixed the compare function to do the
first char comparison in unsigned mode, for consistency with the way
other characters are compared by memcmp().

- In Lib/tkinter/Tkinter.py, fixed Scale.get() to support floats.

- In Lib/urllib.py, fix another case where openedurl wasn't set.

(XXX Sorry, the rest is in totally random order.  No time to fix it.)

- SyntaxError exceptions detected during code generation
(e.g. assignment to an expression) now include a line number.

- Don't leave trailing / or \ in script directory inserted in front of
sys.path.

- Added a note to Tools/scripts/classfix.py abouts its historical
importance.

- Added Misc/Makefile.pre.in, a universal Makefile for extensions
built outside the distribution.

- Rewritten Misc/faq2html.py, by Ka-Ping Yee.

- Install shared modules with mode 555 (needed for performance on some
platforms).

- Some changes to standard library modules to avoid calling append()
with more than one argument -- while supported, this should be
outlawed, and I don't want to set a bad example.

- bdb.py (and hence pdb.py) supports calling run() with a code object
instead of a code string.

- Fixed an embarrassing bug cgi.py which prevented correct uploading
of binary files from Netscape (which doesn't distinguish between
binary and text files).  Also added dormant logging support, which
makes it easier to debug the cgi module itself.

- Added default writer to constructor of NullFormatter class.

- Use binary mode for socket.makefile() calls in ftplib.py.

- The ihooks module no longer "installs" itself upon import -- this
was an experimental feature that helped ironing out some bugs but that
slowed down code that imported it without the need to install it
(e.g. the rexec module).  Also close the file in some cases and add
the __file__ attribute to loaded modules.

- The test program for mailbox.py is now more useful.

- Added getparamnames() to Message class in mimetools.py -- it returns
the names of parameters to the content-type header.

- Fixed a typo in ni that broke the loop stripping "__." from names.

- Fix sys.path[0] for scripts run via pdb.py's new main program.

- profile.py can now also run a script, like pdb.

- Fix a small bug in pyclbr -- don't add names starting with _ when
emulating from ... import *.

- Fixed a series of embarrassing typos in rexec's handling of standard
I/O redirection.  Added some more "safe" built-in modules: cmath,
errno, operator.

- Fixed embarrassing typo in shelve.py.

- Added SliceType and EllipsisType to types.py.

- In urllib.py, added handling for error 301 (same as 302); added
geturl() method to get the URL after redirection.

- Fixed embarrassing typo in xdrlib.py.  Also fixed typo in Setup.in
for _xdrmodule.c and removed redundant #include from _xdrmodule.c.

- Fixed bsddbmodule.c to add binary mode indicator on platforms that
have it.  This should make it working on Windows NT.

- Changed last uses of #ifdef NT to #ifdef MS_WINDOWS or MS_WIN32,
whatever applies.  Also rationalized some other tests for various MS
platforms.

- Added the sources for the NT installer script used for Python
1.4beta3.  Not tested with this release, but better than nothing.

- A compromise in pickle's defenses against Trojan horses: a
user-defined function is now okay where a class is expected.  A
built-in function is not okay, to prevent pickling something that
will execute os.system("rm -f *") when unpickling.

- dis.py will print the name of local variables referenced by local
load/store/delete instructions.

- Improved portability of SimpleHTTPServer module to non-Unix
platform.

- The thread.h interface adds an extra argument to down_sema().  This
only affects other C code that uses thread.c; the Python thread module
doesn't use semaphores (which aren't provided on all platforms where
Python threads are supported).  Note: on NT, this change is not
implemented.

- Fixed some typos in abstract.h; corrected signature of
PyNumber_Coerce, added PyMapping_DelItem.  Also fixed a bug in
abstract.c's PyObject_CallMethod().

- apply(classname, (), {}) now works even if the class has no
__init__() method.

- Implemented complex remainder and divmod() (these would dump core!).
Conversion of complex numbers to int, long int or float now raises an
exception, since there is no meaningful way to do it without losing
information.

- Fixed bug in built-in complex() function which gave the wrong result
for two real arguments.

- Change the hash algorithm for strings -- the multiplier is now
1000003 instead of 3, which gives better spread for short strings.

- New default path for Windows NT, the registry structure now supports
default paths for different install packages.  (Mark Hammond -- the
next PythonWin release will use this.)

- Added more symbols to the python_nt.def file.

- When using GNU readline, set rl_readline_name to "python".

- The Ellipses built-in name has been renamed to Ellipsis -- this is
the correct singular form.  Thanks to Ka-Ping Yee, who saved us from
eternal embarrassment.

- Bumped the PYTHON_API_VERSION to 1006, due to the Ellipses ->
Ellipsis name change.

- Updated the library reference manual.  Added documentation of
restricted mode (rexec, Bastion) and the formatter module (for use
with the htmllib module).  Fixed the documentation of htmllib
(finally).

- The reference manual is now maintained in FrameMaker.

- Upgraded scripts Doc/partparse.py and Doc/texi2html.py.

- Slight improvements to Doc/Makefile.

- Added fcntl.lockf(). This should be used for Unix file locking
instead of the posixfile module; lockf() is more portable.

- The getopt module now supports long option names, thanks to Lars
Wizenius.

- Plenty of changes to Tkinter and Canvas, mostly due to Fred Drake
and Nils Fischbeck.

- Use more bits of time.time() in whrandom's default seed().

- Performance hack for regex module's regs attribute.

- Don't close already closed socket in socket module.

- Correctly handle separators containing embedded nulls in
strop.split, strop.find and strop.rfind.  Also added more detail to
error message for strop.atoi and friends.

- Moved fallback definition for hypot() to Python/hypot.c.

- Added fallback definition for strdup, in Python/strdup.c.

- Fixed some bugs where a function would return 0 to indicate an error
where it should return -1.

- Test for error returned by time.localtime(), and rationalized its MS
tests.

- Added Modules/Setup.local file, which is processed after Setup.

- Corrected bug in toplevel Makefile.in -- execution of regen script
would not use the right PATH and PYTHONPATH.

- Various and sundry NeXT configuration changes (sigh).

- Support systems where libreadline needs neither termcap nor curses.

- Improved ld_so_aix script and python.exp file (for AIX).

- More stringent test for working <stdarg.h> in configure script.

- Removed Demo/www subdirectory -- it was totally out of date.

- Improved demos and docs for Fred Drake's parser module; fixed one
typo in the module itself.


=========================================
==> Release 1.4beta3 (August 26 1996) <==
=========================================


(XXX This is less readable that it should.  I promise to restructure
it for the final 1.4 release.)


What's new in 1.4beta3 (since beta2)?
-------------------------------------

- Name mangling to implement a simple form of class-private variables.
A name of the form "__spam" can't easily be used outside the class.
(This was added in 1.4beta3, but left out of the 1.4beta3 release
message.)

- In urllib.urlopen(): HTTP URLs containing user:passwd@host are now
handled correctly when using a proxy server.

- In ntpath.normpath(): don't truncate to 8+3 format.

- In mimetools.choose_boundary(): don't die when getuid() or getpid()
aren't defined.

- Module urllib: some optimizations to (un)quoting.

- New module MimeWriter for writing MIME documents.

- More changes to formatter module.

- The freeze script works once again and is much more robust (using
sys.prefix etc.).  It also supports a -o option to specify an
output directory.

- New module whichdb recognizes dbm, gdbm and bsddb/dbhash files.

- The Doc/Makefile targets have been reorganized somewhat to remove the 
insistence on always generating PostScript.

- The texinfo to html filter (Doc/texi2html.py) has been improved somewhat.

- "errors.h" has been renamed to "pyerrors.h" to resolve a long-standing 
name conflict on the Mac.

- Linking a module compiled with a different setting for Py_TRACE_REFS now 
generates a linker error rather than a core dump.

- The cgi module has a new convenience function print_exception(), which 
formats a python exception using HTML.  It also fixes a bug in the 
compatibility code and adds a dubious feature which makes it possible to 
have two query strings, one in the URL and one in the POST data.

- A subtle change in the unpickling of class instances makes it possible 
to unpickle in restricted execution mode, where the __dict__ attribute is 
not available (but setattr() is).

- Documentation for os.path.splitext() (== posixpath.splitext()) has been 
cleared up.  It splits at the *last* dot.

- posixfile locking is now also correctly supported on AIX.

- The tempfile module once again honors an initial setting of tmpdir.  It 
now works on Windows, too.

- The traceback module has some new functions to extract, format and print 
the active stack.

- Some translation functions in the urllib module have been made a little 
less sluggish.

- The addtag_* methods for Canvas widgets in Tkinter as well as in the 
separate Canvas class have been fixed so they actually do something 
meaningful.

- A tiny _test() function has been added to Tkinter.py.

- A generic Makefile for dynamically loaded modules is provided in the Misc 
subdirectory (Misc/gMakefile).

- A new version of python-mode.el for Emacs is provided.  See
http://www.python.org/ftp/emacs/pmdetails.html for details.  The
separate file pyimenu.el is no longer needed, imenu support is folded
into python-mode.el.

- The configure script can finally correctly find the readline library in a 
non-standard location.  The LDFLAGS variable is passed on the the Makefiles 
from the configure script.

- Shared libraries are now installed as programs (i.e. with executable 
permission).  This is required on HP-UX and won't hurt on other systems.

- The objc.c module is no longer part of the distribution.  Objective-C 
support may become available as contributed software on the ftp site.

- The sybase module is no longer part of the distribution.  A much
improved sybase module is available as contributed software from the
ftp site.

- _tkinter is now compatible with Tcl 7.5 / Tk 4.1 patch1 on Windows and 
Mac (don't use unpatched Tcl/Tk!).  The default line in the Setup.in file 
now links with Tcl 7.5 / Tk 4.1 rather than 7.4/4.0.

- In Setup, you can now write "*shared*" instead of "*noconfig*", and you 
can use *.so and *.sl as shared libraries.

- Some more fidgeting for AIX shared libraries.

- The mpz module is now compatible with GMP 2.x.  (Not tested by me.)
(Note -- a complete replacement by Niels Mo"ller, called gpmodule, is
available from the contrib directory on the ftp site.)

- A warning is written to sys.stderr when a __del__ method raises an 
exception (formerly, such exceptions were completely ignored).

- The configure script now defines HAVE_OLD_CPP if the C preprocessor is 
incapable of ANSI style token concatenation and stringification.

- All source files (except a few platform specific modules) are once again 
compatible with K&R C compilers as well as ANSI compilers.  In particular,
ANSI-isms have been removed or made conditional in complexobject.c, 
getargs.c and operator.c.

- The abstract object API has three new functions, PyObject_DelItem, 
PySequence_DelItem, and PySequence_DelSlice.

- The operator module has new functions delitem and delslice, and the 
functions "or" and "and" are renamed to "or_" and "and_" (since "or" and 
"and" are reserved words).  ("__or__" and "__and__" are unchanged.)

- The environment module is no longer supported; putenv() is now a function 
in posixmodule (also under NT).

- Error in filter(<function>, "") has been fixed.

- Unrecognized keyword arguments raise TypeError, not KeyError.

- Better portability, fewer bugs and memory leaks, fewer compiler warnings, 
some more documentation.

- Bug in float power boundary case (0.0 to the negative integer power) 
fixed.

- The test of negative number to the float power has been moved from the 
built-in pow() functin to floatobject.c (so complex numbers can yield the 
correct result).

- The bug introduced in beta2 where shared libraries loaded (using 
dlopen()) from the current directory would fail, has been fixed.

- Modules imported as shared libraries now also have a __file__ attribute, 
giving the filename from which they were loaded.  The only modules without 
a __file__ attribute now are built-in modules.

- On the Mac, dynamically loaded modules can end in either ".slb" or 
".<platform>.slb" where <platform> is either "CFM68K" or "ppc".  The ".slb" 
extension should only be used for "fat" binaries.

- C API addition: marshal.c now supports 
PyMarshal_WriteObjectToString(object).

- C API addition: getargs.c now supports
PyArg_ParseTupleAndKeywords(args, kwdict, format, kwnames, ...)
to parse keyword arguments.

- The PC versioning scheme (sys.winver) has changed once again.  the 
version number is now "<digit>.<digit>.<digit>.<apiversion>", where the 
first three <digit>s are the Python version (e.g. "1.4.0" for Python 1.4, 
"1.4.1" for Python 1.4.1 -- the beta level is not included) and 
<apiversion> is the four-digit PYTHON_API_VERSION (currently 1005).

- h2py.py accepts whitespace before the # in CPP directives

- On Solaris 2.5, it should now be possible to use either Posix threads or 
Solaris threads (XXX: how do you select which is used???).  (Note: the 
Python pthreads interface doesn't fully support semaphores yet -- anyone 
care to fix this?)

- Thread support should now work on AIX, using either DCE threads or 
pthreads.

- New file Demo/sockets/unicast.py

- Working Mac port, with CFM68K support, with Tk 4.1 support (though not 
both) (XXX)

- New project setup for PC port, now compatible with PythonWin, with 
_tkinter and NumPy support (XXX)

- New module site.py (XXX)

- New module xdrlib.py and optional support module _xdrmodule.c (XXX)

- parser module adapted to new grammar, complete w/ Doc & Demo (XXX)

- regen script fixed (XXX)

- new machdep subdirectories Lib/{aix3,aix4,next3_3,freebsd2,linux2} (XXX)

- testall now also tests math module (XXX)

- string.atoi c.s. now raise an exception for an empty input string.

- At last, it is no longer necessary to define HAVE_CONFIG_H in order to 
have config.h included at various places.

- Unrecognized keyword arguments now raise TypeError rather than KeyError.

- The makesetup script recognizes files with extension .so or .sl as
(shared) libraries.

- 'access' is no longer a reserved word, and all code related to its 
implementation is gone (or at least #ifdef'ed out).  This should make 
Python a little speedier too!

- Performance enhancements suggested by Sjoerd Mullender.  This includes 
the introduction of two new optional function pointers in type object, 
getattro and setattro, which are like getattr and setattr but take a 
string object instead of a C string pointer.

- New operations in string module: lstrip(s) and rstrip(s) strip whitespace 
only on the left or only on the right, A new optional third argument to 
split() specifies the maximum number of separators honored (so 
splitfields(s, sep, n) returns a list of at most n+1 elements).  (Since 
1.3, splitfields(s, None) is totally equivalent to split(s).)
string.capwords() has an optional second argument specifying the 
separator (which is passed to split()).

- regsub.split() has the same addition as string.split().  regsub.splitx(s, 
sep, maxsep) implements the functionality that was regsub.split(s, 1) in 
1.4beta2 (return a list containing the delimiters as well as the words).

- Final touch for AIX loading, rewritten Misc/AIX-NOTES.

- In Modules/_tkinter.c, when using Tk 4.1 or higher, use className
argument to _tkinter.create() to set Tcl's argv0 variable, so X
resources use the right resource class again.

- Add #undef fabs to Modules/mathmodule.c for macintosh.

- Added some macro renames for AIX in Modules/operator.c.

- Removed spurious 'E' from Doc/liberrno.tex.

- Got rid of some cruft in Misc/ (dlMakefile, pyimenu.el); added new
Misc/gMakefile and new version of Misc/python-mode.el.

- Fixed typo in Lib/ntpath.py (islink has "return false" which gives a
NameError).

- Added missing "from types import *" to Lib/tkinter/Canvas.py.

- Added hint about using default args for __init__ to pickle docs.

- Corrected typo in Inclide/abstract.h: PySequence_Lenth ->
PySequence_Length.

- Some improvements to Doc/texi2html.py.

- In Python/import.c, Cast unsigned char * in struct _frozen to char *
in calls to rds_object().

- In doc/ref4.tex, added note about scope of lambda bodies.

What's new in 1.4beta2 (since beta1)?
-------------------------------------

- Portability bug in the md5.h header solved.

- The PC build procedure now really works, and sets sys.platform to a
meaningful value (a few things were botched in beta 1).  Lib/dos_8x3
is now a standard part of the distribution (alas).

- More improvements to the installation procedure.  Typing "make install" 
now inserts the version number in the pathnames of almost everything 
installed, and creates the machine dependent modules (FCNTL.py etc.) if not 
supplied by the distribution.  (XXX There's still a problem with the latter 
because the "regen" script requires that Python is installed.  Some manual 
intervention may still be required.) (This has been fixed in 1.4beta3.)

- New modules: errno, operator (XXX).

- Changes for use with Numerical Python: builtin function slice() and
Ellipses object, and corresponding syntax:

        x[lo:hi:stride]         ==      x[slice(lo, hi, stride)]
        x[a, ..., z]            ==      x[(a, Ellipses, z)]

- New documentation for errno and cgi mdoules.

- The directory containing the script passed to the interpreter is
inserted in from of sys.path; "." is no longer a default path
component.

- Optional third string argument to string.translate() specifies
characters to delete.  New function string.maketrans() creates a
translation table for translate() or for regex.compile().

- Module posix (and hence module os under Unix) now supports putenv().
Moreover, module os is enhanced so that if putenv() is supported,
assignments to os.environ entries make the appropriate putenv() call.
(XXX the putenv() implementation can leak a small amount of memory per
call.)

- pdb.py can now be invoked from the command line to debug a script:
python pdb.py <script> <arg> ...

- Much improved parseaddr() in rfc822.

- In cgi.py, you can now pass an alternative value for environ to
nearly all functions.

- You can now assign to instance variables whose name begins and ends
with '__'.

- New version of Fred Drake's parser module and associates (token,
symbol, AST).

- New PYTHON_API_VERSION value and .pyc file magic number (again!).

- The "complex" internal structure type is now called "Py_complex" to
avoid name conflicts.

- Numerous small bugs fixed.

- Slight pickle speedups.

- Some slight speedups suggested by Sjoerd (more coming in 1.4 final).

- NeXT portability mods by Bill Bumgarner integrated.

- Modules regexmodule.c, bsddbmodule.c and xxmodule.c have been
converted to new naming style.


What's new in 1.4beta1 (since 1.3)?
-----------------------------------

- Added sys.platform and sys.exec_platform for Bill Janssen.

- Installation has been completely overhauled.  "make install" now installs 
everything, not just the python binary.  Installation uses the install-sh 
script (borrowed from X11) to install each file.

- New functions in the posix module: mkfifo, plock, remove (== unlink),
and ftruncate.  More functions are also available under NT.

- New function in the fcntl module: flock.

- Shared library support for FreeBSD.

- The --with-readline option can now be used without a DIRECTORY argument, 
for systems where libreadline.* is in one of the standard places.  It is 
also possible for it to be a shared library.

- The extension tkinter has been renamed to _tkinter, to avoid confusion 
with Tkinter.py oncase insensitive file systems.  It now supports Tk 4.1 as 
well as 4.0.

- Author's change of address from CWI in Amsterdam, The Netherlands, to 
CNRI in Reston, VA, USA.

- The math.hypot() function is now always available (if it isn't found in 
the C math library, Python provides its own implementation).

- The latex documentation is now compatible with latex2e, thanks to David 
Ascher.

- The expression x**y is now equivalent to pow(x, y).

- The indexing expression x[a, b, c] is now equivalent to x[(a, b, c)].

- Complex numbers are now supported.  Imaginary constants are written with 
a 'j' or 'J' prefix, general complex numbers can be formed by adding a real 
part to an imaginary part, like 3+4j.  Complex numbers are always stored in 
floating point form, so this is equivalent to 3.0+4.0j.  It is also 
possible to create complex numbers with the new built-in function 
complex(re, [im]).  For the footprint-conscious, complex number support can 
be disabled by defining the symbol WITHOUT_COMPLEX.

- New built-in function list() is the long-awaited counterpart of tuple().

- There's a new "cmath" module which provides the same functions as the 
"math" library but with complex arguments and results.  (There are very 
good reasons why math.sqrt(-1) still raises an exception -- you have to use 
cmath.sqrt(-1) to get 1j for an answer.)

- The Python.h header file (which is really the same as allobjects.h except 
it disables support for old style names) now includes several more files, 
so you have to have fewer #include statements in the average extension.

- The NDEBUG symbol is no longer used.  Code that used to be dependent on 
the presence of NDEBUG is now present on the absence of DEBUG.  TRACE_REFS 
and REF_DEBUG have been renamed to Py_TRACE_REFS and Py_REF_DEBUG, 
respectively.  At long last, the source actually compiles and links without 
errors when this symbol is defined.

- Several symbols that didn't follow the new naming scheme have been 
renamed (usually by adding to rename2.h) to use a Py or _Py prefix.  There 
are no external symbols left without a Py or _Py prefix, not even those 
defined by sources that were incorporated from elsewhere (regexpr.c, 
md5c.c).  (Macros are a different story...)

- There are now typedefs for the structures defined in config.c and 
frozen.c.

- New PYTHON_API_VERSION value and .pyc file magic number.

- New module Bastion.  (XXX)

- Improved performance of StringIO module.

- UserList module now supports + and * operators.

- The binhex and binascii modules now actually work.

- The cgi module has been almost totally rewritten and documented.
It now supports file upload and a new data type to handle forms more 
flexibly.

- The formatter module (for use with htmllib) has been overhauled (again).

- The ftplib module now supports passive mode and has doc strings.

- In (ideally) all places where binary files are read or written, the file 
is now correctly opened in binary mode ('rb' or 'wb') so the code will work 
on Mac or PC.

- Dummy versions of os.path.expandvars() and expanduser() are now provided 
on non-Unix platforms.

- Module urllib now has two new functions url2pathname and pathname2url 
which turn local filenames into "file:..." URLs using the same rules as 
Netscape (why be different).  it also supports urlretrieve() with a 
pathname parameter, and honors the proxy environment variables (http_proxy 
etc.).  The URL parsing has been improved somewhat, too.

- Micro improvements to urlparse.  Added urlparse.urldefrag() which 
removes a trailing ``#fragment'' if any.

- The mailbox module now supports MH style message delimiters as well.

- The mhlib module contains some new functionality: setcontext() to set the 
current folder and parsesequence() to parse a sequence as commonly passed 
to MH commands (e.g. 1-10 or last:5).

- New module mimify for conversion to and from MIME format of email 
messages.

- Module ni now automatically installs itself when first imported -- this 
is against the normal rule that modules should define classes and functions 
but not invoke them, but appears more useful in the case that two 
different, independent modules want to use ni's features.

- Some small performance enhancements in module pickle.

- Small interface change to the profile.run*() family of functions -- more 
sensible handling of return values.

- The officially registered Mac creator for Python files is 'Pyth'.  This 
replaces 'PYTH' which was used before but never registered.

- Added regsub.capwords().  (XXX)

- Added string.capwords(), string.capitalize() and string.translate().  
(XXX)

- Fixed an interface bug in the rexec module: it was impossible to pass a 
hooks instance to the RExec class.  rexec now also supports the dynamic 
loading of modules from shared libraries.  Some other interfaces have been 
added too.

- Module rfc822 now caches the headers in a dictionary for more efficient 
lookup.

- The sgmllib module now understands a limited number of SGML "shorthands" 
like <A/.../ for <A>...</A>.  (It's not clear that this was a good idea...)

- The tempfile module actually tries a number of different places to find a 
usable temporary directory.  (This was prompted by certain Linux 
installations that appear to be missing a /usr/tmp directory.) [A bug in 
the implementation that would ignore a pre-existing tmpdir global has been 
fixed in beta3.]

- Much improved and enhanved FileDialog module for Tkinter.

- Many small changes to Tkinter, to bring it more in line with Tk 4.0 (as 
well as Tk 4.1).

- New socket interfaces include ntohs(), ntohl(), htons(), htonl(), and 
s.dup().  Sockets now work correctly on Windows.  On Windows, the built-in 
extension is called _socket and a wrapper module win/socket.py provides 
"makefile()" and "dup()" functionality.  On Windows, the select module 
works only with socket objects.

- Bugs in bsddb module fixed (e.g. missing default argument values).

- The curses extension now includes <ncurses.h> when available.

- The gdbm module now supports opening databases in "fast" mode by 
specifying 'f' as the second character or the mode string.

- new variables sys.prefix and sys.exec_prefix pass corresponding 
configuration options / Makefile variables to the Python programmer.

- The ``new'' module now supports creating new user-defined classes as well 
as instances thereof.

- The soundex module now sports get_soundex() to get the soundex value for an 
arbitrary string (formerly it would only do soundex-based string 
comparison) as well as doc strings.

- New object type "cobject" to safely wrap void pointers for passing them 
between various extension modules.

- More efficient computation of float**smallint.

- The mysterious bug whereby "x.x" (two occurrences of the same 
one-character name) typed from the commandline would sometimes fail 
mysteriously.

- The initialization of the readline function can now be invoked by a C 
extension through PyOS_ReadlineInit().

- There's now an externally visible pointer PyImport_FrozenModules which 
can be changed by an embedding application.

- The argument parsing functions now support a new format character 'D' to 
specify complex numbers.

- Various memory leaks plugged and bugs fixed.

- Improved support for posix threads (now that real implementations are 
beginning to apepar).  Still no fully functioning semaphores.

- Some various and sundry improvements and new entries in the Tools 
directory.


=====================================
==> Release 1.3 (13 October 1995) <==
=====================================

Major change
============

Two words: Keyword Arguments.  See the first section of Chapter 12 of
the Tutorial.

(The rest of this file is textually the same as the remaining sections
of that chapter.)


Changes to the WWW and Internet tools
=====================================

The "htmllib" module has been rewritten in an incompatible fashion.
The new version is considerably more complete (HTML 2.0 except forms,
but including all ISO-8859-1 entity definitions), and easy to use.
Small changes to "sgmllib" have also been made, to better match the
tokenization of HTML as recognized by other web tools.

A new module "formatter" has been added, for use with the new
"htmllib" module.

The "urllib"and "httplib" modules have been changed somewhat to allow
overriding unknown URL types and to support authentication.  They now
use "mimetools.Message" instead of "rfc822.Message" to parse headers.
The "endrequest()" method has been removed from the HTTP class since
it breaks the interaction with some servers.

The "rfc822.Message" class has been changed to allow a flag to be
passed in that says that the file is unseekable.

The "ftplib" module has been fixed to be (hopefully) more robust on
Linux.

Several new operations that are optionally supported by servers have
been added to "nntplib": "xover", "xgtitle", "xpath" and "date".

Other Language Changes
======================

The "raise" statement now takes an optional argument which specifies
the traceback to be used when printing the exception's stack trace.
This must be a traceback object, such as found in "sys.exc_traceback".
When omitted or given as "None", the old behavior (to generate a stack
trace entry for the current stack frame) is used.

The tokenizer is now more tolerant of alien whitespace.  Control-L in
the leading whitespace of a line resets the column number to zero,
while Control-R just before the end of the line is ignored.

Changes to Built-in Operations
==============================

For file objects, "f.read(0)" and "f.readline(0)" now return an empty
string rather than reading an unlimited number of bytes.  For the
latter, omit the argument altogether or pass a negative value.

A new system variable, "sys.platform", has been added.  It specifies
the current platform, e.g. "sunos5" or "linux1".

The built-in functions "input()" and "raw_input()" now use the GNU
readline library when it has been configured (formerly, only
interactive input to the interpreter itself was read using GNU
readline).  The GNU readline library provides elaborate line editing
and history.  The Python debugger ("pdb") is the first beneficiary of
this change.

Two new built-in functions, "globals()" and "locals()", provide access
to dictionaries containming current global and local variables,
respectively.  (These augment rather than replace "vars()", which
returns the current local variables when called without an argument,
and a module's global variables when called with an argument of type
module.)

The built-in function "compile()" now takes a third possible value for
the kind of code to be compiled: specifying "'single'" generates code
for a single interactive statement, which prints the output of
expression statements that evaluate to something else than "None".

Library Changes
===============

There are new module "ni" and "ihooks" that support importing modules
with hierarchical names such as "A.B.C".  This is enabled by writing
"import ni; ni.ni()" at the very top of the main program.  These
modules are amply documented in the Python source.

The module "rexec" has been rewritten (incompatibly) to define a class
and to use "ihooks".

The "string.split()" and "string.splitfields()" functions are now the
same function (the presence or absence of the second argument
determines which operation is invoked); similar for "string.join()"
and "string.joinfields()".

The "Tkinter" module and its helper "Dialog" have been revamped to use
keyword arguments.  Tk 4.0 is now the standard.  A new module
"FileDialog" has been added which implements standard file selection
dialogs.

The optional built-in modules "dbm" and "gdbm" are more coordinated
--- their "open()" functions now take the same values for their "flag"
argument, and the "flag" and "mode" argument have default values (to
open the database for reading only, and to create the database with
mode "0666" minuse the umask, respectively).  The memory leaks have
finally been fixed.

A new dbm-like module, "bsddb", has been added, which uses the BSD DB
package's hash method.

A portable (though slow) dbm-clone, implemented in Python, has been
added for systems where none of the above is provided.  It is aptly
dubbed "dumbdbm".

The module "anydbm" provides a unified interface to "bsddb", "gdbm",
"dbm", and "dumbdbm", choosing the first one available.

A new extension module, "binascii", provides a variety of operations
for conversion of text-encoded binary data.

There are three new or rewritten companion modules implemented in
Python that can encode and decode the most common such formats: "uu"
(uuencode), "base64" and "binhex".

A module to handle the MIME encoding quoted-printable has also been
added: "quopri".

The parser module (which provides an interface to the Python parser's
abstract syntax trees) has been rewritten (incompatibly) by Fred
Drake.  It now lets you change the parse tree and compile the result!

The \code{syslog} module has been upgraded and documented.

Other Changes
=============

The dynamic module loader recognizes the fact that different filenames
point to the same shared library and loads the library only once, so
you can have a single shared library that defines multiple modules.
(SunOS / SVR4 style shared libraries only.)

Jim Fulton's ``abstract object interface'' has been incorporated into
the run-time API.  For more detailes, read the files
"Include/abstract.h" and "Objects/abstract.c".

The Macintosh version is much more robust now.

Numerous things I have forgotten or that are so obscure no-one will
notice them anyway :-)


===================================
==> Release 1.2 (13 April 1995) <==
===================================

- Changes to Misc/python-mode.el:
  - Wrapping and indentation within triple quote strings should work
    properly now.
  - `Standard' bug reporting mechanism (use C-c C-b)
  - py-mark-block was moved to C-c C-m
  - C-c C-v shows you the python-mode version
  - a basic python-font-lock-keywords has been added for Emacs 19
    font-lock colorizations.
  - proper interaction with pending-del and del-sel modes.
  - New py-electric-colon (:) command for improved outdenting.  Also
    py-indent-line (TAB) should handle outdented lines better.
  - New commands py-outdent-left (C-c C-l) and py-indent-right (C-c C-r)

- The Library Reference has been restructured, and many new and
existing modules are now documented, in particular the debugger and
the profiler, as well as the persistency and the WWW/Internet support
modules.

- All known bugs have been fixed.  For example the pow(2,2,3L) bug on
Linux has been fixed.  Also the re-entrancy problems with __del__ have
been fixed.

- All known memory leaks have been fixed.

- Phase 2 of the Great Renaming has been executed.  The header files
now use the new names (PyObject instead of object, etc.).  The linker
also sees the new names.  Most source files still use the old names,
by virtue of the rename2.h header file.  If you include Python.h, you
only see the new names.  Dynamically linked modules have to be
recompiled.  (Phase 3, fixing the rest of the sources, will be
executed gradually with the release later versions.)

- The hooks for implementing "safe-python" (better called "restricted
execution") are in place.  Specifically, the import statement is
implemented by calling the built-in function __import__, and the
built-in names used in a particular scope are taken from the
dictionary __builtins__ in that scope's global dictionary.  See also
the new (unsupported, undocumented) module rexec.py.

- The import statement now supports the syntax "import a.b.c" and
"from a.b.c import name".  No officially supported implementation
exists, but one can be prototyped by replacing the built-in __import__
function.  A proposal by Ken Manheimer is provided as newimp.py.

- All machinery used by the import statement (or the built-in
__import__ function) is now exposed through the new built-in module
"imp" (see the library reference manual).  All dynamic loading
machinery is moved to the new file importdl.c.

- Persistent storage is supported through the use of the modules
"pickle" and "shelve" (implemented in Python).  There's also a "copy"
module implementing deepcopy and normal (shallow) copy operations.
See the library reference manual.

- Documentation strings for many objects types are accessible through
the __doc__ attribute.  Modules, classes and functions support special
syntax to initialize the __doc__ attribute: if the first statement
consists of just a string literal, that string literal becomes the
value of the __doc__ attribute.  The default __doc__ attribute is
None.  Documentation strings are also supported for built-in
functions, types and modules; however this feature hasn't been widely
used yet.  See the 'new' module for an example.  (Basically, the type
object's tp_doc field contains the doc string for the type, and the
4th member of the methodlist structure contains the doc string for the
method.)

- The __coerce__ and __cmp__ methods for user-defined classes once
again work as expected.  As an example, there's a new standard class
Complex in the library.

- The functions posix.popen() and posix.fdopen() now have an optional
third argument to specify the buffer size, and default their second
(mode) argument to 'r' -- in analogy to the builtin open() function.
The same applies to posixfile.open() and the socket method makefile().

- The thread.exit_thread() function now raises SystemExit so that
'finally' clauses are honored and a memory leak is plugged.

- Improved X11 and Motif support, by Sjoerd Mullender.  This extension
is being maintained and distributed separately.

- Improved support for the Apple Macintosh, in part by Jack Jansen,
e.g. interfaces to (a few) resource mananger functions, get/set file
type and creator, gestalt, sound manager, speech manager, MacTCP, comm
toolbox, and the think C console library.  This is being maintained
and distributed separately.

- Improved version for Windows NT, by Mark Hammond.  This is being
maintained and distributed separately.

- Used autoconf 2.0 to generate the configure script.  Adapted
configure.in to use the new features in autoconf 2.0.

- It now builds on the NeXT without intervention, even on the 3.3
Sparc pre-release.

- Characters passed to isspace() and friends are masked to nonnegative
values.

- Correctly compute pow(-3.0, 3).

- Fix portability problems with getopt (configure now checks for a
non-GNU getopt).

- Don't add frozenmain.o to libPython.a.

- Exceptions can now be classes.  ALl built-in exceptions are still
string objects, but this will change in the future.

- The socket module exports a long list of socket related symbols.
(More built-in modules will export their symbolic constants instead of
relying on a separately generated Python module.)

- When a module object is deleted, it clears out its own dictionary.
This fixes a circularity in the references between functions and
their global dictionary.

- Changed the error handling by [new]getargs() e.g. for "O&".

- Dynamic loading of modules using shared libraries is supported for
several new platforms.

- Support "O&", "[...]" and "{...}" in mkvalue().

- Extension to findmethod(): findmethodinchain() (where a chain is a
linked list of methodlist arrays).  The calling interface for
findmethod() has changed: it now gets a pointer to the (static!)
methodlist structure rather than just to the function name -- this
saves copying flags etc. into the (short-lived) method object.

- The callable() function is now public.

- Object types can define a few new operations by setting function
pointers in the type object structure: tp_call defines how an object
is called, and tp_str defines how an object's str() is computed.


===================================
==> Release 1.1.1 (10 Nov 1994) <==
===================================

This is a pure bugfix release again.  See the ChangeLog file for details.

One exception: a few new features were added to tkinter.


=================================
==> Release 1.1 (11 Oct 1994) <==
=================================

This release adds several new features, improved configuration and
portability, and fixes more bugs than I can list here (including some
memory leaks).

The source compiles and runs out of the box on more platforms than
ever -- including Windows NT.  Makefiles or projects for a variety of
non-UNIX platforms are provided.

APOLOGY: some new features are badly documented or not at all.  I had
the choice -- postpone the new release indefinitely, or release it
now, with working code but some undocumented areas.  The problem with
postponing the release is that people continue to suffer from existing
bugs, and send me patches based on the previous release -- which I
can't apply directly because my own source has changed.  Also, some
new modules (like signal) have been ready for release for quite some
time, and people are anxiously waiting for them.  In the case of
signal, the interface is simple enough to figure out without
documentation (if you're anxious enough :-).  In this case it was not
simple to release the module on its own, since it relies on many small
patches elsewhere in the source.

For most new Python modules, the source code contains comments that
explain how to use them.  Documentation for the Tk interface, written
by Matt Conway, is available as tkinter-doc.tar.gz from the Python
home and mirror ftp sites (see Misc/FAQ for ftp addresses).  For the
new operator overloading facilities, have a look at Demo/classes:
Complex.py and Rat.py show how to implement a numeric type without and
with __coerce__ method.  Also have a look at the end of the Tutorial
document (Doc/tut.tex).  If you're still confused: use the newsgroup
or mailing list.


New language features:

    - More flexible operator overloading for user-defined classes
    (INCOMPATIBLE WITH PREVIOUS VERSIONS!)  See end of tutorial.

    - Classes can define methods named __getattr__, __setattr__ and
    __delattr__ to trap attribute accesses.  See end of tutorial.

    - Classes can define method __call__ so instances can be called
    directly.  See end of tutorial.


New support facilities:

    - The Makefiles (for the base interpreter as well as for extensions)
    now support creating dynamically loadable modules if the platform
    supports shared libraries.

    - Passing the interpreter a .pyc file as script argument will execute
    the code in that file.  (On the Mac such files can be double-clicked!)

    - New Freeze script, to create independently distributable "binaries"
    of Python programs -- look in Demo/freeze

    - Improved h2py script (in Demo/scripts) follows #includes and
    supports macros with one argument

    - New module compileall generates .pyc files for all modules in a
    directory (tree) without also executing them

    - Threads should work on more platforms


New built-in modules:

    - tkinter (support for Tcl's Tk widget set) is now part of the base
    distribution

    - signal allows catching or ignoring UNIX signals (unfortunately still
    undocumented -- any taker?)

    - termios provides portable access to POSIX tty settings

    - curses provides an interface to the System V curses library

    - syslog provides an interface to the (BSD?) syslog daemon

    - 'new' provides interfaces to create new built-in object types
    (e.g. modules and functions)

    - sybase provides an interface to SYBASE database


New/obsolete built-in methods:

    - callable(x) tests whether x can be called

    - sockets now have a setblocking() method

    - sockets no longer have an allowbroadcast() method

    - socket methods send() and sendto() return byte count


New standard library modules:

    - types.py defines standard names for built-in types, e.g. StringType

    - urlparse.py parses URLs according to the latest Internet draft

    - uu.py does uuencode/uudecode (not the fastest in the world, but
    quicker than installing uuencode on a non-UNIX machine :-)

    - New, faster and more powerful profile module.py

    - mhlib.py provides interface to MH folders and messages


New facilities for extension writers (unfortunately still
undocumented):

    - newgetargs() supports optional arguments and improved error messages

    - O!, O& O? formats for getargs allow more versatile type checking of
    non-standard types

    - can register pending asynchronous callback, to be called the next
    time the Python VM begins a new instruction (Py_AddPendingCall)

    - can register cleanup routines to be called when Python exits
    (Py_AtExit)

    - makesetup script understands C++ files in Setup file (use file.C
    or file.cc)

    - Make variable OPT is passed on to sub-Makefiles

    - An init<module>() routine may signal an error by not entering
    the module in the module table and raising an exception instead

    - For long module names, instead of foobarbletchmodule.c you can
    use foobarbletch.c

    - getintvalue() and getfloatvalue() try to convert any object
    instead of requiring an "intobject" or "floatobject"

    - All the [new]getargs() formats that retrieve an integer value
    will now also work if a float is passed

    - C function listtuple() converts list to tuple, fast

    - You should now call sigcheck() instead of intrcheck();
    sigcheck() also sets an exception when it returns nonzero


====================================
==> Release 1.0.3 (14 July 1994) <==
====================================

This release consists entirely of bug fixes to the C sources; see the
head of ../ChangeLog for a complete list.  Most important bugs fixed:

- Sometimes the format operator (string%expr) would drop the last
character of the format string

- Tokenizer looped when last line did not end in \n

- Bug when triple-quoted string ended in quote plus newline

- Typo in socketmodule (listen) (== instead of =)

- typing vars() at the >>> prompt would cause recursive output


==================================
==> Release 1.0.2 (4 May 1994) <==
==================================

Overview of the most visible changes.  Bug fixes are not listed.  See
also ChangeLog.

Tokens
------

* String literals follow Standard C rules: they may be continued on
the next line using a backslash; adjacent literals are concatenated
at compile time.

* A new kind of string literals, surrounded by triple quotes (""" or
'''), can be continued on the next line without a backslash.

Syntax
------

* Function arguments may have a default value, e.g. def f(a, b=1);
defaults are evaluated at function definition time.  This also applies
to lambda.

* The try-except statement has an optional else clause, which is
executed when no exception occurs in the try clause.

Interpreter
-----------

* The result of a statement-level expression is no longer printed,
except_ for expressions entered interactively.  Consequently, the -k
command line option is gone.

* The result of the last printed interactive expression is assigned to
the variable '_'.

* Access to implicit global variables has been speeded up by removing
an always-failing dictionary lookup in the dictionary of local
variables (mod suggested by Steve Makewski and Tim Peters).

* There is a new command line option, -u, to force stdout and stderr
to be unbuffered.

* Incorporated Steve Majewski's mods to import.c for dynamic loading
under AIX.

* Fewer chances of dumping core when trying to reload or re-import
static built-in, dynamically loaded built-in, or frozen modules.

* Loops over sequences now don't ask for the sequence's length when
they start, but try to access items 0, 1, 2, and so on until they hit
an IndexError.  This makes it possible to create classes that generate
infinite or indefinite sequences a la Steve Majewski.  This affects
for loops, the (not) in operator, and the built-in functions filter(),
map(), max(), min(), reduce().

Changed Built-in operations
---------------------------

* The '%' operator on strings (printf-style formatting) supports a new
feature (adapted from a patch by Donald Beaudry) to allow
'%(<key>)<format>' % {...} to take values from a dictionary by name
instead of from a tuple by position (see also the new function
vars()).

* The '%s' formatting operator is changed to accept any type and
convert it to a string using str().

* Dictionaries with more than 20,000 entries can now be created
(thanks to Steve Kirsch).

New Built-in Functions
----------------------

* vars() returns a dictionary containing the local variables; vars(m)
returns a dictionary containing the variables of module m.  Note:
dir(x) is now equivalent to vars(x).keys().

Changed Built-in Functions
--------------------------

* open() has an optional third argument to specify the buffer size: 0
for unbuffered, 1 for line buffered, >1 for explicit buffer size, <0
for default.

* open()'s second argument is now optional; it defaults to "r".

* apply() now checks that its second argument is indeed a tuple.

New Built-in Modules
--------------------

Changed Built-in Modules
------------------------

The thread module no longer supports exit_prog().

New Python Modules
------------------

* Module addpack contains a standard interface to modify sys.path to
find optional packages (groups of related modules).

* Module urllib contains a number of functions to access
World-Wide-Web files specified by their URL.

* Module httplib implements the client side of the HTTP protocol used
by World-Wide-Web servers.

* Module gopherlib implements the client side of the Gopher protocol.

* Module mailbox (by Jack Jansen) contains a parser for UNIX and MMDF
style mailbox files.

* Module random contains various random distributions, e.g. gauss().

* Module lockfile locks and unlocks open files using fcntl (inspired
by a similar module by Andy Bensky).

* Module ntpath (by Jaap Vermeulen) implements path operations for
Windows/NT.

* Module test_thread (in Lib/test) contains a small test set for the
thread module.

Changed Python Modules
----------------------

* The string module's expandvars() function is now documented and is
implemented in Python (using regular expressions) instead of forking
off a shell process.

* Module rfc822 now supports accessing the header fields using the
mapping/dictionary interface, e.g. h['subject'].

* Module pdb now makes it possible to set a break on a function
(syntax: break <expression>, where <expression> yields a function
object).

Changed Demos
-------------

* The Demo/scripts/freeze.py script is working again (thanks to Jaap
Vermeulen).

New Demos
---------

* Demo/threads/Generator.py is a proposed interface for restartable
functions a la Tim Peters.

* Demo/scripts/newslist.py, by Quentin Stafford-Fraser, generates a
directory full of HTML pages which between them contain links to all
the newsgroups available on your server.

* Demo/dns contains a DNS (Domain Name Server) client.

* Demo/lutz contains miscellaneous demos by Mark Lutz (e.g. psh.py, a
nice enhanced Python shell!!!).

* Demo/turing contains a Turing machine by Amrit Prem.

Documentation
-------------

* Documented new language features mentioned above (but not all new
modules).

* Added a chapter to the Tutorial describing recent additions to
Python.

* Clarified some sentences in the reference manual,
e.g. break/continue, local/global scope, slice assignment.

Source Structure
----------------

* Moved Include/tokenizer.h to Parser/tokenizer.h.

* Added Python/getopt.c for systems that don't have it.

Emacs mode
----------

* Indentation of continuated lines is done more intelligently;
consequently the variable py-continuation-offset is gone.

========================================
==> Release 1.0.1 (15 February 1994) <==
========================================

* Many portability fixes should make it painless to build Python on
several new platforms, e.g. NeXT, SEQUENT, WATCOM, DOS, and Windows.

* Fixed test for <stdarg.h> -- this broke on some platforms.

* Fixed test for shared library dynalic loading -- this broke on SunOS
4.x using the GNU loader.

* Changed order and number of SVR4 networking libraries (it is now
-lsocket -linet -lnsl, if these libraries exist).

* Installing the build intermediate stages with "make libainstall" now
also installs config.c.in, Setup and makesetup, which are used by the
new Extensions mechanism.

* Improved README file contains more hints and new troubleshooting
section.

* The built-in module strop now defines fast versions of three more
functions of the standard string module: atoi(), atol() and atof().
The strop versions of atoi() and atol() support an optional second
argument to specify the base (default 10).  NOTE: you don't have to
explicitly import strop to use the faster versions -- the string
module contains code to let versions from stop override the default
versions.

* There is now a working Lib/dospath.py for those who use Python under
DOS (or Windows).  Thanks, Jaap!

* There is now a working Modules/dosmodule.c for DOS (or Windows)
system calls.

* Lib.os.py has been reorganized (making it ready for more operating
systems).

* Lib/ospath.py is now obsolete (use os.path instead).

* Many fixes to the tutorial to make it match Python 1.0.  Thanks,
Tim!

* Fixed Doc/Makefile, Doc/README and various scripts there.

* Added missing description of fdopen to Doc/libposix.tex.

* Made cleanup() global, for the benefit of embedded applications.

* Added parsing of addresses and dates to Lib/rfc822.py.

* Small fixes to Lib/aifc.py, Lib/sunau.py, Lib/tzparse.py to make
them usable at all.

* New module Lib/wave.py reads RIFF (*.wav) audio files.

* Module Lib/filewin.py moved to Lib/stdwin/filewin.py where it
belongs.

* New options and comments for Modules/makesetup (used by new
Extension mechanism).

* Misc/HYPE contains text of announcement of 1.0.0 in comp.lang.misc
and elsewhere.

* Fixed coredump in filter(None, 'abcdefg').


=======================================
==> Release 1.0.0 (26 January 1994) <==
=======================================

As is traditional, so many things have changed that I can't pretend to
be complete in these release notes, but I'll try anyway :-)

Note that the very last section is labeled "remaining bugs".


Source organization and build process
-------------------------------------

* The sources have finally been split: instead of a single src
subdirectory there are now separate directories Include, Parser,
Grammar, Objects, Python and Modules.  Other directories also start
with a capital letter: Misc, Doc, Lib, Demo.

* A few extensions (notably Amoeba and X support) have been moved to a
separate subtree Extensions, which is no longer in the core
distribution, but separately ftp'able as extensions.tar.Z.  (The
distribution contains a placeholder Ext-dummy with a description of
the Extensions subtree as well as the most recent versions of the
scripts used there.)

* A few large specialized demos (SGI video and www) have been
moved to a separate subdirectory Demo2, which is no longer in the core
distribution, but separately ftp'able as demo2.tar.Z.

* Parts of the standard library have been moved to subdirectories:
there are now standard subdirectories stdwin, test, sgi and sun4.

* The configuration process has radically changed: I now use GNU
autoconf.  This makes it much easier to build on new Unix flavors, as
well as fully supporting VPATH (if your Make has it).  The scripts
Configure.py and Addmodule.sh are no longer needed.  Many source files
have been adapted in order to work with the symbols that the configure
script generated by autoconf defines (or not); the resulting source is
much more portable to different C compilers and operating systems,
even non Unix systems (a Mac port was done in an afternoon).  See the
toplevel README file for a description of the new build process.

* GNU readline (a slightly newer version) is now a subdirectory of the
Python toplevel.  It is still not automatically configured (being
totally autoconf-unaware :-).  One problem has been solved: typing
Control-C to a readline prompt will now work.  The distribution no
longer contains a "super-level" directory (above the python toplevel
directory), and dl, dl-dld and GNU dld are no longer part of the
Python distribution (you can still ftp them from
ftp.cwi.nl:/pub/dynload).

* The DOS functions have been taken out of posixmodule.c and moved
into a separate file dosmodule.c.

* There's now a separate file version.c which contains nothing but
the version number.

* The actual main program is now contained in config.c (unless NO_MAIN
is defined); pythonmain.c now contains a function realmain() which is
called from config.c's main().

* All files needed to use the built-in module md5 are now contained in
the distribution.  The module has been cleaned up considerably.


Documentation
-------------

* The library manual has been split into many more small latex files,
so it is easier to edit Doc/lib.tex file to create a custom library
manual, describing only those modules supported on your system.  (This
is not automated though.)

* A fourth manual has been added, titled "Extending and Embedding the
Python Interpreter" (Doc/ext.tex), which collects information about
the interpreter which was previously spread over several files in the
misc subdirectory.

* The entire documentation is now also available on-line for those who
have a WWW browser (e.g. NCSA Mosaic).  Point your browser to the URL
"http://www.cwi.nl/~guido/Python.html".


Syntax
------

* Strings may now be enclosed in double quotes as well as in single
quotes.  There is no difference in interpretation.  The repr() of
string objects will use double quotes if the string contains a single
quote and no double quotes.  Thanks to Amrit Prem for these changes!

* There is a new keyword 'exec'.  This replaces the exec() built-in
function.  If a function contains an exec statement, local variable
optimization is not performed for that particular function, thus
making assignment to local variables in exec statements less
confusing.  (As a consequence, os.exec and python.exec have been
renamed to execv.)

* There is a new keyword 'lambda'.  An expression of the form

        lambda <parameters> : <expression>

yields an anonymous function.  This is really only syntactic sugar;
you can just as well define a local function using

        def some_temporary_name(<parameters>): return <expression>

Lambda expressions are particularly useful in combination with map(),
filter() and reduce(), described below.  Thanks to Amrit Prem for
submitting this code (as well as map(), filter(), reduce() and
xrange())!


Built-in functions
------------------

* The built-in module containing the built-in functions is called
__builtin__ instead of builtin.

* New built-in functions map(), filter() and reduce() perform standard
functional programming operations (though not lazily):

- map(f, seq) returns a new sequence whose items are the items from
seq with f() applied to them.

- filter(f, seq) returns a subsequence of seq consisting of those
items for which f() is true.

- reduce(f, seq, initial) returns a value computed as follows:
        acc = initial
        for item in seq: acc = f(acc, item)
        return acc

* New function xrange() creates a "range object".  Its arguments are
the same as those of range(), and when used in a for loop a range
objects also behaves identical.  The advantage of xrange() over
range() is that its representation (if the range contains many
elements) is much more compact than that of range().  The disadvantage
is that the result cannot be used to initialize a list object or for
the "Python idiom" [RED, GREEN, BLUE] = range(3).  On some modern
architectures, benchmarks have shown that "for i in range(...): ..."
actually executes *faster* than "for i in xrange(...): ...", but on
memory starved machines like PCs running DOS range(100000) may be just
too big to be represented at all...

* Built-in function exec() has been replaced by the exec statement --
see above.


The interpreter
---------------

* Syntax errors are now not printed to stderr by the parser, but
rather the offending line and other relevant information are packed up
in the SyntaxError exception argument.  When the main loop catches a
SyntaxError exception it will print the error in the same format as
previously, but at the proper position in the stack traceback.

* You can now set a maximum to the number of traceback entries
printed by assigning to sys.tracebacklimit.  The default is 1000.

* The version number in .pyc files has changed yet again.

* It is now possible to have a .pyc file without a corresponding .py
file.  (Warning: this may break existing installations if you have an
old .pyc file lingering around somewhere on your module search path
without a corresponding .py file, when there is a .py file for a
module of the same name further down the path -- the new interpreter
will find the first .pyc file and complain about it, while the old
interpreter would ignore it and use the .py file further down.)

* The list sys.builtin_module_names is now sorted and also contains
the names of a few hardwired built-in modules (sys, __main__ and
__builtin__).

* A module can now find its own name by accessing the global variable
__name__.  Assigning to this variable essentially renames the module
(it should also be stored under a different key in sys.modules).
A neat hack follows from this: a module that wants to execute a main
program when called as a script no longer needs to compare
sys.argv[0]; it can simply do "if __name__ == '__main__': main()".

* When an object is printed by the print statement, its implementation
of str() is used.  This means that classes can define __str__(self) to
direct how their instances are printed.  This is different from
__repr__(self), which should define an unambigous string
representation of the instance.  (If __str__() is not defined, it
defaults to __repr__().)

* Functions and code objects can now be compared meaningfully.

* On systems supporting SunOS or SVR4 style shared libraries, dynamic
loading of modules using shared libraries is automatically configured.
Thanks to Bill Jansen and Denis Severson for contributing this change!


Built-in objects
----------------

* File objects have acquired a new method writelines() which is the
reverse of readlines().  (It does not actually write lines, just a
list of strings, but the symmetry makes the choice of name OK.)


Built-in modules
----------------

* Socket objects no longer support the avail() method.  Use the select
module instead, or use this function to replace it:

        def avail(f):
                import select
                return f in select.select([f], [], [], 0)[0]

* Initialization of stdwin is done differently.  It actually modifies
sys.argv (taking out the options the X version of stdwin recognizes)
the first time it is imported.

* A new built-in module parser provides a rudimentary interface to the
python parser.  Corresponding standard library modules token and symbol
defines the numeric values of tokens and non-terminal symbols.

* The posix module has aquired new functions setuid(), setgid(),
execve(), and exec() has been renamed to execv().

* The array module is extended with 8-byte object swaps, the 'i'
format character, and a reverse() method.  The read() and write()
methods are renamed to fromfile() and tofile().

* The rotor module has freed of portability bugs.  This introduces a
backward compatibility problem: strings encoded with the old rotor
module can't be decoded by the new version.

* For select.select(), a timeout (4th) argument of None means the same
as leaving the timeout argument out.

* Module strop (and hence standard library module string) has aquired
a new function: rindex().  Thanks to Amrit Prem!

* Module regex defines a new function symcomp() which uses an extended
regular expression syntax: parenthesized subexpressions may be labeled
using the form "\(<labelname>...\)", and the group() method can return
sub-expressions by name.  Thanks to Tracy Tims for these changes!

* Multiple threads are now supported on Solaris 2.  Thanks to Sjoerd
Mullender!


Standard library modules
------------------------

* The library is now split in several subdirectories: all stuff using
stdwin is in Lib/stdwin, all SGI specific (or SGI Indigo or GL) stuff
is in Lib/sgi, all Sun Sparc specific stuff is in Lib/sun4, and all
test modules are in Lib/test.  The default module search path will
include all relevant subdirectories by default.

* Module os now knows about trying to import dos.  It defines
functions execl(), execle(), execlp() and execvp().

* New module dospath (should be attacked by a DOS hacker though).

* All modules defining classes now define __init__() constructors
instead of init() methods.  THIS IS AN INCOMPATIBLE CHANGE!

* Some minor changes and bugfixes module ftplib (mostly Steve
Majewski's suggestions); the debug() method is renamed to
set_debuglevel().

* Some new test modules (not run automatically by testall though):
test_audioop, test_md5, test_rgbimg, test_select.

* Module string now defines rindex() and rfind() in analogy of index()
and find().  It also defines atof() and atol() (and corresponding
exceptions) in analogy to atoi().

* Added help() functions to modules profile and pdb.

* The wdb debugger (now in Lib/stdwin) now shows class or instance
variables on a double click.  Thanks to Sjoerd Mullender!

* The (undocumented) module lambda has gone -- you couldn't import it
any more, and it was basically more a demo than a library module...


Multimedia extensions
---------------------

* The optional built-in modules audioop and imageop are now standard
parts of the interpreter.  Thanks to Sjoerd Mullender and Jack Jansen
for contributing this code!

* There's a new operation in audioop: minmax().

* There's a new built-in module called rgbimg which supports portable
efficient reading of SGI RCG image files.  Thanks also to Paul
Haeberli for the original code!  (Who will contribute a GIF reader?)

* The module aifc is gone -- you should now always use aifc, which has
received a facelift.

* There's a new module sunau., for reading Sun (and NeXT) audio files.

* There's a new module audiodev which provides a uniform interface to
(SGI Indigo and Sun Sparc) audio hardware.

* There's a new module sndhdr which recognizes various sound files by
looking in their header and checking for various magic words.


Optimizations
-------------

* Most optimizations below can be configured by compile-time flags.
Thanks to Sjoerd Mullender for submitting these optimizations!

* Small integers (default -1..99) are shared -- i.e. if two different
functions compute the same value it is possible (but not
guaranteed!!!) that they return the same *object*.  Python programs
can detect this but should *never* rely on it.

* Empty tuples (which all compare equal) are shared in the same
manner.

* Tuples of size up to 20 (default) are put in separate free lists
when deallocated.

* There is a compile-time option to cache a string's hash function,
but this appeared to have a negligeable effect, and as it costs 4
bytes per string it is disabled by default.


Embedding Python
----------------

* The initialization interface has been simplified somewhat.  You now
only call "initall()" to initialize the interpreter.

* The previously announced renaming of externally visible identifiers
has not been carried out.  It will happen in a later release.  Sorry.


Miscellaneous bugs that have been fixed
---------------------------------------

* All known portability bugs.

* Version 0.9.9 dumped core in <listobject>.sort() which has been
fixed.  Thanks to Jaap Vermeulen for fixing this and posting the fix
on the mailing list while I was away!

* Core dump on a format string ending in '%', e.g. in the expression
'%' % None.

* The array module yielded a bogus result for concatenation (a+b would
yield a+a).

* Some serious memory leaks in strop.split() and strop.splitfields().

* Several problems with the nis module.

* Subtle problem when copying a class method from another class
through assignment (the method could not be called).


Remaining bugs
--------------

* One problem with 64-bit machines remains -- since .pyc files are
portable and use only 4 bytes to represent an integer object, 64-bit
integer literals are silently truncated when written into a .pyc file.
Work-around: use eval('123456789101112').

* The freeze script doesn't work any more.  A new and more portable
one can probably be cooked up using tricks from Extensions/mkext.py.

* The dos support hasn't been tested yet.  (Really Soon Now we should
have a PC with a working C compiler!)


===================================
==> Release 0.9.9 (29 Jul 1993) <==
===================================

I *believe* these are the main user-visible changes in this release,
but there may be others.  SGI users may scan the {src,lib}/ChangeLog
files for improvements of some SGI specific modules, e.g. aifc and
cl.  Developers of extension modules should also read src/ChangeLog.


Naming of C symbols used by the Python interpreter
--------------------------------------------------

* This is the last release using the current naming conventions.  New
naming conventions are explained in the file misc/NAMING.
Summarizing, all externally visible symbols get (at least) a "Py"
prefix, and most functions are renamed to the standard form
PyModule_FunctionName.

* Writers of extensions are urged to start using the new naming
conventions.  The next release will use the new naming conventions
throughout (it will also have a different source directory
structure).

* As a result of the preliminary work for the great renaming, many
functions that were accidentally global have been made static.


BETA X11 support
----------------

* There are now modules interfacing to the X11 Toolkit Intrinsics, the
Athena widgets, and the Motif 1.1 widget set.  These are not yet
documented except through the examples and README file in the demo/x11
directory.  It is expected that this interface will be replaced by a
more powerful and correct one in the future, which may or may not be
backward compatible.  In other words, this part of the code is at most
BETA level software!  (Note: the rest of Python is rock solid as ever!)

* I understand that the above may be a bit of a disappointment,
however my current schedule does not allow me to change this situation
before putting the release out of the door.  By releasing it
undocumented and buggy, at least some of the (working!) demo programs,
like itr (my Internet Talk Radio browser) become available to a larger
audience.

* There are also modules interfacing to SGI's "Glx" widget (a GL
window wrapped in a widget) and to NCSA's "HTML" widget (which can
format HyperText Markup Language, the document format used by the
World Wide Web).

* I've experienced some problems when building the X11 support.  In
particular, the Xm and Xaw widget sets don't go together, and it
appears that using X11R5 is better than using X11R4.  Also the threads
module and its link time options may spoil things.  My own strategy is
to build two Python binaries: one for use with X11 and one without
it, which can contain a richer set of built-in modules.  Don't even
*think* of loading the X11 modules dynamically...


Environmental changes
---------------------

* Compiled files (*.pyc files) created by this Python version are
incompatible with those created by the previous version.  Both
versions detect this and silently create a correct version, but it
means that it is not a good idea to use the same library directory for
an old and a new interpreter, since they will start to "fight" over
the *.pyc files...

* When a stack trace is printed, the exception is printed last instead
of first.  This means that if the beginning of the stack trace
scrolled out of your window you can still see what exception caused
it.

* Sometimes interrupting a Python operation does not work because it
hangs in a blocking system call.  You can now kill the interpreter by
interrupting it three times.  The second time you interrupt it, a
message will be printed telling you that the third interrupt will kill
the interpreter.  The "sys.exitfunc" feature still makes limited
clean-up possible in this case.


Changes to the command line interface
-------------------------------------

* The python usage message is now much more informative.

* New option -i enters interactive mode after executing a script --
useful for debugging.

* New option -k raises an exception when an expression statement
yields a value other than None.

* For each option there is now also a corresponding environment
variable.


Using Python as an embedded language
------------------------------------

* The distribution now contains (some) documentation on the use of
Python as an "embedded language" in other applications, as well as a
simple example.  See the file misc/EMBEDDING and the directory embed/.


Speed improvements
------------------

* Function local variables are now generally stored in an array and
accessed using an integer indexing operation, instead of through a
dictionary lookup.  (This compensates the somewhat slower dictionary
lookup caused by the generalization of the dictionary module.)


Changes to the syntax
---------------------

* Continuation lines can now *sometimes* be written without a
backslash: if the continuation is contained within nesting (), [] or
{} brackets the \ may be omitted.  There's a much improved
python-mode.el in the misc directory which knows about this as well.

* You can no longer use an empty set of parentheses to define a class
without base classes.  That is, you no longer write this:

        class Foo(): # syntax error
                ...

You must write this instead:

        class Foo:
                ...

This was already the preferred syntax in release 0.9.8 but many
people seemed not to have picked it up.  There's a Python script that
fixes old code: demo/scripts/classfix.py.

* There's a new reserved word: "access".  The syntax and semantics are
still subject of of research and debate (as well as undocumented), but
the parser knows about the keyword so you must not use it as a
variable, function, or attribute name.


Changes to the semantics of the language proper
-----------------------------------------------

* The following compatibility hack is removed: if a function was
defined with two or more arguments, and called with a single argument
that was a tuple with just as many arguments, the items of this tuple
would be used as the arguments.  This is no longer supported.


Changes to the semantics of classes and instances
-------------------------------------------------

* Class variables are now also accessible as instance variables for
reading (assignment creates an instance variable which overrides the
class variable of the same name though).

* If a class attribute is a user-defined function, a new kind of
object is returned: an "unbound method".  This contains a pointer to
the class and can only be called with a first argument which is a
member of that class (or a derived class).

* If a class defines a method __init__(self, arg1, ...) then this
method is called when a class instance is created by the classname()
construct.  Arguments passed to classname() are passed to the
__init__() method.  The __init__() methods of base classes are not
automatically called; the derived __init__() method must call these if
necessary (this was done so the derived __init__() method can choose
the call order and arguments for the base __init__() methods).

* If a class defines a method __del__(self) then this method is called
when an instance of the class is about to be destroyed.  This makes it
possible to implement clean-up of external resources attached to the
instance.  As with __init__(), the __del__() methods of base classes
are not automatically called.  If __del__ manages to store a reference
to the object somewhere, its destruction is postponed; when the object
is again about to be destroyed its __del__() method will be called
again.

* Classes may define a method __hash__(self) to allow their instances
to be used as dictionary keys.  This must return a 32-bit integer.


Minor improvements
------------------

* Function and class objects now know their name (the name given in
the 'def' or 'class' statement that created them).

* Class instances now know their class name.


Additions to built-in operations
--------------------------------

* The % operator with a string left argument implements formatting
similar to sprintf() in C.  The right argument is either a single
value or a tuple of values.  All features of Standard C sprintf() are
supported except %p.

* Dictionaries now support almost any key type, instead of just
strings.  (The key type must be an immutable type or must be a class
instance where the class defines a method __hash__(), in order to
avoid losing track of keys whose value may change.)

* Built-in methods are now compared properly: when comparing x.meth1
and y.meth2, if x is equal to y and the methods are defined by the
same function, x.meth1 compares equal to y.meth2.


Additions to built-in functions
-------------------------------

* str(x) returns a string version of its argument.  If the argument is
a string it is returned unchanged, otherwise it returns `x`.

* repr(x) returns the same as `x`.  (Some users found it easier to
have this as a function.)

* round(x) returns the floating point number x rounded to an whole
number, represented as a floating point number.  round(x, n) returns x
rounded to n digits.

* hasattr(x, name) returns true when x has an attribute with the given
name.

* hash(x) returns a hash code (32-bit integer) of an arbitrary
immutable object's value.

* id(x) returns a unique identifier (32-bit integer) of an arbitrary
object.

* compile() compiles a string to a Python code object.

* exec() and eval() now support execution of code objects.


Changes to the documented part of the library (standard modules)
----------------------------------------------------------------

* os.path.normpath() (a.k.a. posixpath.normpath()) has been fixed so
the border case '/foo/..' returns '/' instead of ''.

* A new function string.find() is added with similar semantics to
string.index(); however when it does not find the given substring it
returns -1 instead of raising string.index_error.


Changes to built-in modules
---------------------------

* New optional module 'array' implements operations on sequences of
integers or floating point numbers of a particular size.  This is
useful to manipulate large numerical arrays or to read and write
binary files consisting of numerical data.

* Regular expression objects created by module regex now support a new
method named group(), which returns one or more \(...\) groups by number.
The number of groups is increased from 10 to 100.

* Function compile() in module regex now supports an optional mapping
argument; a variable casefold is added to the module which can be used
as a standard uppercase to lowercase mapping.

* Module time now supports many routines that are defined in the
Standard C time interface (<time.h>): gmtime(), localtime(),
asctime(), ctime(), mktime(), as well as these variables (taken from
System V): timezone, altzone, daylight and tzname.  (The corresponding
functions in the undocumented module calendar have been removed; the
undocumented and unfinished module tzparse is now obsolete and will
disappear in a future release.)

* Module strop (the fast built-in version of standard module string)
now uses C's definition of whitespace instead of fixing it to space,
tab and newline; in practice this usually means that vertical tab,
form feed and return are now also considered whitespace.  It exports
the string of characters that are considered whitespace as well as the
characters that are considered lowercase or uppercase.

* Module sys now defines the variable builtin_module_names, a list of
names of modules built into the current interpreter (including not
yet imported, but excluding two special modules that always have to be
defined -- sys and builtin).

* Objects created by module sunaudiodev now also support flush() and
close() methods.

* Socket objects created by module socket now support an optional
flags argument for their methods sendto() and recvfrom().

* Module marshal now supports dumping to and loading from strings,
through the functions dumps() and loads().

* Module stdwin now supports some new functionality.  You may have to
ftp the latest version: ftp.cwi.nl:/pub/stdwin/stdwinforviews.tar.Z.)


Bugs fixed
----------

* Fixed comparison of negative long integers.

* The tokenizer no longer botches input lines longer than BUFSIZ.

* Fixed several severe memory leaks in module select.

* Fixed memory leaks in modules socket and sv.

* Fixed memory leak in divmod() for long integers.

* Problems with definition of floatsleep() on Suns fixed.

* Many portability bugs fixed (and undoubtedly new ones added :-).


Changes to the build procedure
------------------------------

* The Makefile supports some new targets: "make default" and "make
all".  Both are by normally equivalent to "make python".

* The Makefile no longer uses $> since it's not supported by all
versions of Make.

* The header files now all contain #ifdef constructs designed to make
it safe to include the same header file twice, as well as support for
inclusion from C++ programs (automatic extern "C" { ... } added).


Freezing Python scripts
-----------------------

* There is now some support for "freezing" a Python script as a
stand-alone executable binary file.  See the script
demo/scripts/freeze.py.  It will require some site-specific tailoring
of the script to get this working, but is quite worthwhile if you write
Python code for other who may not have built and installed Python.


MS-DOS
------

* A new MS-DOS port has been done, using MSC 6.0 (I believe).  Thanks,
Marcel van der Peijl!  This requires fewer compatibility hacks in
posixmodule.c.  The executable is not yet available but will be soon
(check the mailing list).

* The default PYTHONPATH has changed.


Changes for developers of extension modules
-------------------------------------------

* Read src/ChangeLog for full details.


SGI specific changes
--------------------

* Read src/ChangeLog for full details.


==================================
==> Release 0.9.8 (9 Jan 1993) <==
==================================

I claim no completeness here, but I've tried my best to scan the log
files throughout my source tree for interesting bits of news.  A more
complete account of the changes is to be found in the various
ChangeLog files. See also "News for release 0.9.7beta" below if you're
still using release 0.9.6, and the file HISTORY if you have an even
older release.

        --Guido


Changes to the language proper
------------------------------

There's only one big change: the conformance checking for function
argument lists (of user-defined functions only) is stricter.  Earlier,
you could get away with the following:

        (a) define a function of one argument and call it with any
            number of arguments; if the actual argument count wasn't
            one, the function would receive a tuple containing the
            arguments arguments (an empty tuple if there were none).

        (b) define a function of two arguments, and call it with more
            than two arguments; if there were more than two arguments,
            the second argument would be passed as a tuple containing
            the second and further actual arguments.

(Note that an argument (formal or actual) that is a tuple is counted as
one; these rules don't apply inside such tuples, only at the top level
of the argument list.)

Case (a) was needed to accommodate variable-length argument lists;
there is now an explicit "varargs" feature (precede the last argument
with a '*').  Case (b) was needed for compatibility with old class
definitions: up to release 0.9.4 a method with more than one argument
had to be declared as "def meth(self, (arg1, arg2, ...)): ...".
Version 0.9.6 provide better ways to handle both casees, bot provided
backward compatibility; version 0.9.8 retracts the compatibility hacks
since they also cause confusing behavior if a function is called with
the wrong number of arguments.

There's a script that helps converting classes that still rely on (b),
provided their methods' first argument is called "self":
demo/scripts/methfix.py.

If this change breaks lots of code you have developed locally, try
#defining COMPAT_HACKS in ceval.c.

(There's a third compatibility hack, which is the reverse of (a): if a
function is defined with two or more arguments, and called with a
single argument that is a tuple with just as many arguments, the items
of this tuple will be used as the arguments.  Although this can (and
should!) be done using the built-in function apply() instead, it isn't
withdrawn yet.)


One minor change: comparing instance methods works like expected, so
that if x is an instance of a user-defined class and has a method m,
then (x.m==x.m) yields 1.


The following was already present in 0.9.7beta, but not explicitly
mentioned in the NEWS file: user-defined classes can now define types
that behave in almost allrespects like numbers.  See
demo/classes/Rat.py for a simple example.


Changes to the build process
----------------------------

The Configure.py script and the Makefile has been made somewhat more
bullet-proof, after reports of (minor) trouble on certain platforms.

There is now a script to patch Makefile and config.c to add a new
optional built-in module: Addmodule.sh.  Read the script before using!

Useing Addmodule.sh, all optional modules can now be configured at
compile time using Configure.py, so there are no modules left that
require dynamic loading.

The Makefile has been fixed to make it easier to use with the VPATH
feature of some Make versions (e.g. SunOS).


Changes affecting portability
-----------------------------

Several minor portability problems have been solved, e.g. "malloc.h"
has been renamed to "mymalloc.h", "strdup.c" is no longer used, and
the system now tolerates malloc(0) returning 0.

For dynamic loading on the SGI, Jack Jansen's dl 1.6 is now
distributed with Python.  This solves several minor problems, in
particular scripts invoked using #! can now use dynamic loading.


Changes to the interpreter interface
------------------------------------

On popular demand, there's finally a "profile" feature for interactive
use of the interpreter.  If the environment variable $PYTHONSTARTUP is
set to the name of an existing file, Python statements in this file
are executed when the interpreter is started in interactive mode.

There is a new clean-up mechanism, complementing try...finally: if you
assign a function object to sys.exitfunc, it will be called when
Python exits or receives a SIGTERM or SIGHUP signal.

The interpreter is now generally assumed to live in
/usr/local/bin/python (as opposed to /usr/local/python).  The script
demo/scripts/fixps.py will update old scripts in place (you can easily
modify it to do other similar changes).

Most I/O that uses sys.stdin/stdout/stderr will now use any object
assigned to those names as long as the object supports readline() or
write() methods.

The parser stack has been increased to 500 to accommodate more
complicated expressions (7 levels used to be the practical maximum,
it's now about 38).

The limit on the size of the *run-time* stack has completely been
removed -- this means that tuple or list displays can contain any
number of elements (formerly more than 50 would crash the
interpreter). 


Changes to existing built-in functions and methods
--------------------------------------------------

The built-in functions int(), long(), float(), oct() and hex() now
also apply to class instalces that define corresponding methods
(__int__ etc.).


New built-in functions
----------------------

The new functions str() and repr() convert any object to a string.
The function repr(x) is in all respects equivalent to `x` -- some
people prefer a function for this.  The function str(x) does the same
except if x is already a string -- then it returns x unchanged
(repr(x) adds quotes and escapes "funny" characters as octal escapes).

The new function cmp(x, y) returns -1 if x<y, 0 if x==y, 1 if x>y.


Changes to general built-in modules
-----------------------------------

The time module's functions are more general: time() returns a
floating point number and sleep() accepts one.  Their accuracies
depends on the precision of the system clock.  Millisleep is no longer
needed (although it still exists for now), but millitimer is still
needed since on some systems wall clock time is only available with
seconds precision, while a source of more precise time exists that
isn't synchronized with the wall clock.  (On UNIX systems that support
the BSD gettimeofday() function, time.time() is as time.millitimer().)

The string representation of a file object now includes an address:
'<file 'filename', mode 'r' at #######>' where ###### is a hex number
(the object's address) to make it unique.

New functions added to posix: nice(), setpgrp(), and if your system
supports them: setsid(), setpgid(), tcgetpgrp(), tcsetpgrp().

Improvements to the socket module: socket objects have new methods
getpeername() and getsockname(), and the {get,set}sockopt methods can
now get/set any kind of option using strings built with the new struct
module.  And there's a new function fromfd() which creates a socket
object given a file descriptor (useful for servers started by inetd,
which have a socket connected to stdin and stdout).


Changes to SGI-specific built-in modules
----------------------------------------

The FORMS library interface (fl) now requires FORMS 2.1a.  Some new
functions have been added and some bugs have been fixed.

Additions to al (audio library interface): added getname(),
getdefault() and getminmax().

The gl modules doesn't call "foreground()" when initialized (this
caused some problems) like it dit in 0.9.7beta (but not before).
There's a new gl function 'gversion() which returns a version string.

The interface to sv (Indigo video interface) has totally changed.
(Sorry, still no documentation, but see the examples in
demo/sgi/{sv,video}.)


Changes to standard library modules
-----------------------------------

Most functions in module string are now much faster: they're actually
implemented in C.  The module containing the C versions is called
"strop" but you should still import "string" since strop doesn't
provide all the interfaces defined in string (and strop may be renamed
to string when it is complete in a future release).

string.index() now accepts an optional third argument giving an index
where to start searching in the first argument, so you can find second
and further occurrences (this is similar to the regular expression
functions in regex).

The definition of what string.splitfields(anything, '') should return
is changed for the last time: it returns a singleton list containing
its whole first argument unchanged.  This is compatible with
regsub.split() which also ignores empty delimiter matches.

posixpath, macpath: added dirname() and normpath() (and basename() to
macpath).

The mainloop module (for use with stdwin) can now demultiplex input
from other sources, as long as they can be polled with select().


New built-in modules
--------------------

Module struct defines functions to pack/unpack values to/from strings
representing binary values in native byte order.

Module strop implements C versions of many functions from string (see
above).

Optional module fcntl defines interfaces to fcntl() and ioctl() --
UNIX only.  (Not yet properly documented -- see however src/fcntl.doc.)

Optional module mpz defines an interface to an altaernative long
integer implementation, the GNU MPZ library.

Optional module md5 uses the GNU MPZ library to calculate MD5
signatures of strings.

There are also optional new modules specific to SGI machines: imageop
defines some simple operations to images represented as strings; sv
interfaces to the Indigo video board; cl interfaces to the (yet
unreleased) compression library.


New standard library modules
----------------------------

(Unfortunately the following modules are not all documented; read the
sources to find out more about them!)

autotest: run testall without showing any output unless it differs
from the expected output

bisect: use bisection to insert or find an item in a sorted list

colorsys: defines conversions between various color systems (e.g. RGB
<-> YUV)

nntplib: a client interface to NNTP servers

pipes: utility to construct pipeline from templates, e.g. for
conversion from one file format to another using several utilities.

regsub: contains three functions that are more or less compatible with
awk functions of the same name: sub() and gsub() do string
substitution, split() splits a string using a regular expression to
define how separators are define.

test_types: test operations on the built-in types of Python

toaiff: convert various audio file formats to AIFF format

tzparse: parse the TZ environment parameter (this may be less general
than it could be, let me know if you fix it).

(Note that the obsolete module "path" no longer exists.)


New SGI-specific library modules
--------------------------------

CL: constants for use with the built-in compression library interface (cl)

Queue: a multi-producer, multi-consumer queue class implemented for
use with the built-in thread module

SOCKET: constants for use with built-in module socket, e.g. to set/get
socket options.  This is SGI-specific because the constants to be
passed are system-dependent.  You can generate a version for your own
system by running the script demo/scripts/h2py.py with
/usr/include/sys/socket.h as input.

cddb: interface to the database used the the CD player

torgb: convert various image file types to rgb format (requires pbmplus)


New demos
---------

There's an experimental interface to define Sun RPC clients and
servers in demo/rpc.

There's a collection of interfaces to WWW, WAIS and Gopher (both
Python classes and program providing a user interface) in demo/www.
This includes a program texi2html.py which converts texinfo files to
HTML files (the format used hy WWW).

The ibrowse demo has moved from demo/stdwin/ibrowse to demo/ibrowse.

For SGI systems, there's a whole collection of programs and classes
that make use of the Indigo video board in demo/sgi/{sv,video}.  This
represents a significant amount of work that we're giving away!

There are demos "rsa" and "md5test" that exercise the mpz and md5
modules, respectively.  The rsa demo is a complete implementation of
the RSA public-key cryptosystem!

A bunch of games and examples submitted by Stoffel Erasmus have been
included in demo/stoffel.

There are miscellaneous new files in some existing demo
subdirectories: classes/bitvec.py, scripts/{fixps,methfix}.py,
sgi/al/cmpaf.py, sockets/{mcast,gopher}.py.

There are also many minor changes to existing files, but I'm too lazy
to run a diff and note the differences -- you can do this yourself if
you save the old distribution's demos.  One highlight: the
stdwin/python.py demo is much improved!


Changes to the documentation
----------------------------

The LaTeX source for the library uses different macros to enable it to
be converted to texinfo, and from there to INFO or HTML format so it
can be browsed as a hypertext.  The net result is that you can now
read the Python library documentation in Emacs info mode!


Changes to the source code that affect C extension writers
----------------------------------------------------------

The function strdup() no longer exists (it was used only in one places
and is somewhat of a a portability problem sice some systems have the
same function in their C library.

The functions NEW() and RENEW() allocate one spare byte to guard
against a NULL return from malloc(0) being taken for an error, but
this should not be relied upon.


=========================
==> Release 0.9.7beta <==
=========================


Changes to the language proper
------------------------------

User-defined classes can now implement operations invoked through
special syntax, such as x[i] or `x` by defining methods named
__getitem__(self, i) or __repr__(self), etc.


Changes to the build process
----------------------------

Instead of extensive manual editing of the Makefile to select
compile-time options, you can now run a Configure.py script.
The Makefile as distributed builds a minimal interpreter sufficient to
run Configure.py.  See also misc/BUILD

The Makefile now includes more "utility" targets, e.g. install and
tags/TAGS

Using the provided strtod.c and strtol.c are now separate options, as
on the Sun the provided strtod.c dumps core :-(

The regex module is now an option chosen by the Makefile, since some
(old) C compilers choke on regexpr.c


Changes affecting portability
-----------------------------

You need STDWIN version 0.9.7 (released 30 June 1992) for the stdwin
interface

Dynamic loading is now supported for Sun (and other non-COFF systems)
throug dld-3.2.3, as well as for SGI (a new version of Jack Jansen's
DL is out, 1.4)

The system-dependent code for the use of the select() system call is
moved to one file: myselect.h

Thanks to Jaap Vermeulen, the code should now port cleanly to the
SEQUENT


Changes to the interpreter interface
------------------------------------

The interpretation of $PYTHONPATH in the environment is different: it
is inserted in front of the default path instead of overriding it


Changes to existing built-in functions and methods
--------------------------------------------------

List objects now support an optional argument to their sort() method,
which is a comparison function similar to qsort(3) in C

File objects now have a method fileno(), used by the new select module
(see below)


New built-in function
---------------------

coerce(x, y): take two numbers and return a tuple containing them
both converted to a common type


Changes to built-in modules
---------------------------

sys: fixed core dumps in settrace() and setprofile()

socket: added socket methods setsockopt() and getsockopt(); and
fileno(), used by the new select module (see below)

stdwin: added fileno() == connectionnumber(), in support of new module
select (see below)

posix: added get{eg,eu,g,u}id(); waitpid() is now a separate function.

gl: added qgetfd()

fl: added several new functions, fixed several obscure bugs, adapted
to FORMS 2.1


Changes to standard modules
---------------------------

posixpath: changed implementation of ismount()

string: atoi() no longer mistakes leading zero for octal number

...


New built-in modules
--------------------

Modules marked "dynamic only" are not configured at compile time but
can be loaded dynamically.  You need to turn on the DL or DLD option in
the Makefile for support dynamic loading of modules (this requires
external code).

select: interfaces to the BSD select() system call

dbm: interfaces to the (new) dbm library (dynamic only)

nis: interfaces to some NIS functions (aka yellow pages)

thread: limited form of multiple threads (sgi only)

audioop: operations useful for audio programs, e.g. u-LAW and ADPCM
coding (dynamic only)

cd: interface to Indigo SCSI CDROM player audio library (sgi only)

jpeg: read files in JPEG format (dynamic only, sgi only; needs
external code)

imgfile: read SGI image files (dynamic only, sgi only)

sunaudiodev: interface to sun's /dev/audio (dynamic only, sun only)

sv: interface to Indigo video library (sgi only)

pc: a minimal set of MS-DOS interfaces (MS-DOS only)

rotor: encryption, by Lance Ellinghouse (dynamic only)


New standard modules
--------------------

Not all these modules are documented.  Read the source:
lib/<modulename>.py.  Sometimes a file lib/<modulename>.doc contains
additional documentation.

imghdr: recognizes image file headers

sndhdr: recognizes sound file headers

profile: print run-time statistics of Python code

readcd, cdplayer: companion modules for built-in module cd (sgi only)

emacs: interface to Emacs using py-connect.el (see below).

SOCKET: symbolic constant definitions for socket options

SUNAUDIODEV: symbolic constant definitions for sunaudiodef (sun only)

SV: symbolic constat definitions for sv (sgi only)

CD: symbolic constat definitions for cd (sgi only)


New demos
---------

scripts/pp.py: execute Python as a filter with a Perl-like command
line interface

classes/: examples using the new class features

threads/: examples using the new thread module

sgi/cd/: examples using the new cd module


Changes to the documentation
----------------------------

The last-minute syntax changes of release 0.9.6 are now reflected
everywhere in the manuals

The reference manual has a new section (3.2) on implementing new kinds
of numbers, sequences or mappings with user classes

Classes are now treated extensively in the tutorial (chapter 9)

Slightly restructured the system-dependent chapters of the library
manual

The file misc/EXTENDING incorporates documentation for mkvalue() and
a new section on error handling

The files misc/CLASSES and misc/ERRORS are no longer necessary

The doc/Makefile now creates PostScript files automatically


Miscellaneous changes
---------------------

Incorporated Tim Peters' changes to python-mode.el, it's now version
1.06

A python/Emacs bridge (provided by Terrence M. Brannon) lets a Python
program running in an Emacs buffer execute Emacs lisp code.  The
necessary Python code is in lib/emacs.py.  The Emacs code is
misc/py-connect.el (it needs some external Emacs lisp code)


Changes to the source code that affect C extension writers
----------------------------------------------------------

New service function mkvalue() to construct a Python object from C
values according to a "format" string a la getargs()

Most functions from pythonmain.c moved to new pythonrun.c which is
in libpython.a.  This should make embedded versions of Python easier

ceval.h is split in eval.h (which needs compile.h and only declares
eval_code) and ceval.h (which doesn't need compile.hand declares the
rest)

ceval.h defines macros BGN_SAVE / END_SAVE for use with threads (to
improve the parallellism of multi-threaded programs by letting other
Python code run when a blocking system call or something similar is
made)

In structmember.[ch], new member types BYTE, CHAR and unsigned
variants have been added

New file xxmodule.c is a template for new extension modules.


==================================
==> RELEASE 0.9.6 (6 Apr 1992) <==
==================================

Misc news in 0.9.6:
- Restructured the misc subdirectory
- Reference manual completed, library manual much extended (with indexes!)
- the GNU Readline library is now distributed standard with Python
- the script "../demo/scripts/classfix.py" fixes Python modules using old
  class syntax
- Emacs python-mode.el (was python.el) vastly improved (thanks, Tim!)
- Because of the GNU copyleft business I am not using the GNU regular
  expression implementation but a free re-implementation by Tatu Ylonen
  that recently appeared in comp.sources.misc (Bravo, Tatu!)

New features in 0.9.6:
- stricter try stmt syntax: cannot mix except and finally clauses on 1 try
- New module 'os' supplants modules 'mac' and 'posix' for most cases;
  module 'path' is replaced by 'os.path'
- os.path.split() return value differs from that of old path.split()
- sys.exc_type, sys.exc_value, sys.exc_traceback are set to the exception
  currently being handled
- sys.last_type, sys.last_value, sys.last_traceback remember last unhandled
  exception
- New function string.expandtabs() expands tabs in a string
- Added times() interface to posix (user & sys time of process & children)
- Added uname() interface to posix (returns OS type, hostname, etc.)
- New built-in function execfile() is like exec() but from a file
- Functions exec() and eval() are less picky about whitespace/newlines
- New built-in functions getattr() and setattr() access arbitrary attributes
- More generic argument handling in built-in functions (see "./EXTENDING")
- Dynamic loading of modules written in C or C++ (see "./DYNLOAD")
- Division and modulo for long and plain integers with negative operands
  have changed; a/b is now floor(float(a)/float(b)) and a%b is defined
  as a-(a/b)*b.  So now the outcome of divmod(a,b) is the same as
  (a/b, a%b) for integers.  For floats, % is also changed, but of course
  / is unchanged, and divmod(x,y) does not yield (x/y, x%y)...
- A function with explicit variable-length argument list can be declared
  like this: def f(*args): ...; or even like this: def f(a, b, *rest): ...
- Code tracing and profiling features have been added, and two source
  code debuggers are provided in the library (pdb.py, tty-oriented,
  and wdb, window-oriented); you can now step through Python programs!
  See sys.settrace() and sys.setprofile(), and "../lib/pdb.doc"
- '==' is now the only equality operator; "../demo/scripts/eqfix.py" is
  a script that fixes old Python modules
- Plain integer right shift now uses sign extension
- Long integer shift/mask operations now simulate 2's complement
  to give more useful results for negative operands
- Changed/added range checks for long/plain integer shifts
- Options found after "-c command" are now passed to the command in sys.argv
  (note subtle incompatiblity with "python -c command -- -options"!)
- Module stdwin is better protected against touching objects after they've
  been closed; menus can now also be closed explicitly
- Stdwin now uses its own exception (stdwin.error)

New features in 0.9.5 (released as Macintosh application only, 2 Jan 1992):
- dictionary objects can now be compared properly; e.g., {}=={} is true
- new exception SystemExit causes termination if not caught;
  it is raised by sys.exit() so that 'finally' clauses can clean up,
  and it may even be caught.  It does work interactively!
- new module "regex" implements GNU Emacs style regular expressions;
  module "regexp" is rewritten in Python for backward compatibility
- formal parameter lists may contain trailing commas

Bugs fixed in 0.9.6:
- assigning to or deleting a list item with a negative index dumped core
- divmod(-10L,5L) returned (-3L, 5L) instead of (-2L, 0L)

Bugs fixed in 0.9.5:
- masking operations involving negative long integers gave wrong results


===================================
==> RELEASE 0.9.4 (24 Dec 1991) <==
===================================

- new function argument handling (see below)
- built-in apply(func, args) means func(args[0], args[1], ...)
- new, more refined exceptions
- new exception string values (NameError = 'NameError' etc.)
- better checking for math exceptions
- for sequences (string/tuple/list), x[-i] is now equivalent to x[len(x)-i]
- fixed list assignment bug: "a[1:1] = a" now works correctly
- new class syntax, without extraneous parentheses
- new 'global' statement to assign global variables from within a function


New class syntax
----------------

You can now declare a base class as follows:

        class B:                        # Was: class B():
                def some_method(self): ...
                ...

and a derived class thusly:

        class D(B):                     # Was: class D() = B():
                def another_method(self, arg): ...

Multiple inheritance looks like this:

        class M(B, D):                  # Was: class M() = B(), D():
                def this_or_that_method(self, arg): ...

The old syntax is still accepted by Python 0.9.4, but will disappear
in Python 1.0 (to be posted to comp.sources).


New 'global' statement
----------------------

Every now and then you have a global variable in a module that you
want to change from within a function in that module -- say, a count
of calls to a function, or an option flag, etc.  Until now this was
not directly possible.  While several kludges are known that
circumvent the problem, and often the need for a global variable can
be avoided by rewriting the module as a class, this does not always
lead to clearer code.

The 'global' statement solves this dilemma.  Its occurrence in a
function body means that, for the duration of that function, the
names listed there refer to global variables.  For instance:

        total = 0.0
        count = 0

        def add_to_total(amount):
                global total, count
                total = total + amount
                count = count + 1

'global' must be repeated in each function where it is needed.  The
names listed in a 'global' statement must not be used in the function
before the statement is reached.

Remember that you don't need to use 'global' if you only want to *use*
a global variable in a function; nor do you need ot for assignments to
parts of global variables (e.g., list or dictionary items or
attributes of class instances).  This has not changed; in fact
assignment to part of a global variable was the standard workaround.


New exceptions
--------------

Several new exceptions have been defined, to distinguish more clearly
between different types of errors.

name                    meaning                                 was

AttributeError          reference to non-existing attribute     NameError
IOError                 unexpected I/O error                    RuntimeError
ImportError             import of non-existing module or name   NameError
IndexError              invalid string, tuple or list index     RuntimeError
KeyError                key not in dictionary                   RuntimeError
OverflowError           numeric overflow                        RuntimeError
SyntaxError             invalid syntax                          RuntimeError
ValueError              invalid argument value                  RuntimeError
ZeroDivisionError       division by zero                        RuntimeError

The string value of each exception is now its name -- this makes it
easier to experimentally find out which operations raise which
exceptions; e.g.:

        >>> KeyboardInterrupt
        'KeyboardInterrupt'
        >>>


New argument passing semantics
------------------------------

Off-line discussions with Steve Majewski and Daniel LaLiberte have
convinced me that Python's parameter mechanism could be changed in a
way that made both of them happy (I hope), kept me happy, fixed a
number of outstanding problems, and, given some backward compatibility
provisions, would only break a very small amount of existing code --
probably all mine anyway.  In fact I suspect that most Python users
will hardly notice the difference.  And yet it has cost me at least
one sleepless night to decide to make the change...

Philosophically, the change is quite radical (to me, anyway): a
function is no longer called with either zero or one argument, which
is a tuple if there appear to be more arguments.  Every function now
has an argument list containing 0, 1 or more arguments.  This list is
always implemented as a tuple, and it is a (run-time) error if a
function is called with a different number of arguments than expected.

What's the difference? you may ask.  The answer is, very little unless
you want to write variadic functions -- functions that may be called
with a variable number of arguments.  Formerly, you could write a
function that accepted one or more arguments with little trouble, but
writing a function that could be called with either 0 or 1 argument
(or more) was next to impossible.  This is now a piece of cake: you
can simply declare an argument that receives the entire argument
tuple, and check its length -- it will be of size 0 if there are no
arguments.

Another anomaly of the old system was the way multi-argument methods
(in classes) had to be declared, e.g.:

        class Point():
                def init(self, (x, y, color)): ...
                def setcolor(self, color): ...
                dev moveto(self, (x, y)): ...
                def draw(self): ...

Using the new scheme there is no need to enclose the method arguments
in an extra set of parentheses, so the above class could become:

        class Point:
                def init(self, x, y, color): ...
                def setcolor(self, color): ...
                dev moveto(self, x, y): ...
                def draw(self): ...

That is, the equivalence rule between methods and functions has
changed so that now p.moveto(x,y) is equivalent to Point.moveto(p,x,y)
while formerly it was equivalent to Point.moveto(p,(x,y)).

A special backward compatibility rule makes that the old version also
still works: whenever a function with exactly two arguments (at the top
level) is called with more than two arguments, the second and further
arguments are packed into a tuple and passed as the second argument.
This rule is invoked independently of whether the function is actually a
method, so there is a slight chance that some erroneous calls of
functions expecting two arguments with more than that number of
arguments go undetected at first -- when the function tries to use the
second argument it may find it is a tuple instead of what was expected.
Note that this rule will be removed from future versions of the
language; it is a backward compatibility provision *only*.

Two other rules and a new built-in function handle conversion between
tuples and argument lists:

Rule (a): when a function with more than one argument is called with a
single argument that is a tuple of the right size, the tuple's items
are used as arguments.

Rule (b): when a function with exactly one argument receives no
arguments or more than one, that one argument will receive a tuple
containing the arguments (the tuple will be empty if there were no
arguments).


A new built-in function, apply(), was added to support functions that
need to call other functions with a constructed argument list.  The call

        apply(function, tuple)

is equivalent to

        function(tuple[0], tuple[1], ..., tuple[len(tuple)-1])


While no new argument syntax was added in this phase, it would now be
quite sensible to add explicit syntax to Python for default argument
values (as in C++ or Modula-3), or a "rest" argument to receive the
remaining arguments of a variable-length argument list.


========================================================
==> Release 0.9.3 (never made available outside CWI) <==
========================================================

- string sys.version shows current version (also printed on interactive entry)
- more detailed exceptions, e.g., IOError, ZeroDivisionError, etc.
- 'global' statement to declare module-global variables assigned in functions.
- new class declaration syntax: class C(Base1, Base2, ...): suite
  (the old syntax is still accepted -- be sure to convert your classes now!)
- C shifting and masking operators: << >> ~ & ^ | (for ints and longs).
- C comparison operators: == != (the old = and <> remain valid).
- floating point numbers may now start with a period (e.g., .14).
- definition of integer division tightened (always truncates towards zero).
- new builtins hex(x), oct(x) return hex/octal string from (long) integer.
- new list method l.count(x) returns the number of occurrences of x in l.
- new SGI module: al (Indigo and 4D/35 audio library).
- the FORMS interface (modules fl and FL) now uses FORMS 2.0
- module gl: added lrect{read,write}, rectzoom and pixmode;
  added (non-GL) functions (un)packrect.
- new socket method: s.allowbroadcast(flag).
- many objects support __dict__, __methods__ or __members__.
- dir() lists anything that has __dict__.
- class attributes are no longer read-only.
- classes support __bases__, instances support __class__ (and __dict__).
- divmod() now also works for floats.
- fixed obscure bug in eval('1            ').


===================================
==> Release 0.9.2 (Autumn 1991) <==
===================================

Highlights
----------

- tutorial now (almost) complete; library reference reorganized
- new syntax: continue statement; semicolons; dictionary constructors;
  restrictions on blank lines in source files removed
- dramatically improved module load time through precompiled modules
- arbitrary precision integers: compute 2 to the power 1000 and more...
- arithmetic operators now accept mixed type operands, e.g., 3.14/4
- more operations on list: remove, index, reverse; repetition
- improved/new file operations: readlines, seek, tell, flush, ...
- process management added to the posix module: fork/exec/wait/kill etc.
- BSD socket operations (with example servers and clients!)
- many new STDWIN features (color, fonts, polygons, ...)
- new SGI modules: font manager and FORMS library interface


Extended list of changes in 0.9.2
---------------------------------

Here is a summary of the most important user-visible changes in 0.9.2,
in somewhat arbitrary order.  Changes in later versions are listed in
the "highlights" section above.


1. Changes to the interpreter proper

- Simple statements can now be separated by semicolons.
  If you write "if t: s1; s2", both s1 and s2 are executed
  conditionally.
- The 'continue' statement was added, with semantics as in C.
- Dictionary displays are now allowed on input: {key: value, ...}.
- Blank lines and lines bearing only a comment no longer need to
  be indented properly.  (A completely empty line still ends a multi-
  line statement interactively.)
- Mixed arithmetic is supported, 1 compares equal to 1.0, etc.
- Option "-c command" to execute statements from the command line
- Compiled versions of modules are cached in ".pyc" files, giving a
  dramatic improvement of start-up time
- Other, smaller speed improvements, e.g., extracting characters from
  strings, looking up single-character keys, and looking up global
  variables
- Interrupting a print operation raises KeyboardInterrupt instead of
  only cancelling the print operation
- Fixed various portability problems (it now passes gcc with only
  warnings -- more Standard C compatibility will be provided in later
  versions)
- Source is prepared for porting to MS-DOS
- Numeric constants are now checked for overflow (this requires
  standard-conforming strtol() and strtod() functions; a correct
  strtol() implementation is provided, but the strtod() provided
  relies on atof() for everything, including error checking


2. Changes to the built-in types, functions and modules

- New module socket: interface to BSD socket primitives
- New modules pwd and grp: access the UNIX password and group databases
- (SGI only:) New module "fm" interfaces to the SGI IRIX Font Manager
- (SGI only:) New module "fl" interfaces to Mark Overmars' FORMS library
- New numeric type: long integer, for unlimited precision
        - integer constants suffixed with 'L' or 'l' are long integers
        - new built-in function long(x) converts int or float to long
        - int() and float() now also convert from long integers
- New built-in function:
        - pow(x, y) returns x to the power y
- New operation and methods for lists:
        - l*n returns a new list consisting of n concatenated copies of l
        - l.remove(x) removes the first occurrence of the value x from l
        - l.index(x) returns the index of the first occurrence of x in l
        - l.reverse() reverses l in place
- New operation for tuples:
        - t*n returns a tuple consisting of n concatenated copies of t
- Improved file handling:
        - f.readline() no longer restricts the line length, is faster,
          and isn't confused by null bytes; same for raw_input()
        - f.read() without arguments reads the entire (rest of the) file
        - mixing of print and sys.stdout.write() has different effect
- New methods for files:
        - f.readlines() returns a list containing the lines of the file,
          as read with f.readline()
        - f.flush(), f.tell(), f.seek() call their stdio counterparts
        - f.isatty() tests for "tty-ness"
- New posix functions:
        - _exit(), exec(), fork(), getpid(), getppid(), kill(), wait()
        - popen() returns a file object connected to a pipe
        - utime() replaces utimes() (the latter is not a POSIX name)
- New stdwin features, including:
        - font handling
        - color drawing
        - scroll bars made optional
        - polygons
        - filled and xor shapes
        - text editing objects now have a 'settext' method


3. Changes to the standard library

- Name change: the functions path.cat and macpath.cat are now called
  path.join and macpath.join
- Added new modules: formatter, mutex, persist, sched, mainloop
- Added some modules and functionality to the "widget set" (which is
  still under development, so please bear with me):
        DirList, FormSplit, TextEdit, WindowSched
- Fixed module testall to work non-interactively
- Module string:
        - added functions join() and joinfields()
        - fixed center() to work correct and make it "transitive"
- Obsolete modules were removed: util, minmax
- Some modules were moved to the demo directory


4. Changes to the demonstration programs

- Added new useful scipts: byteyears, eptags, fact, from, lfact,
  objgraph, pdeps, pi, primes, ptags, which
- Added a bunch of socket demos
- Doubled the speed of ptags
- Added new stdwin demos: microedit, miniedit
- Added a windowing interface to the Python interpreter: python (most
  useful on the Mac)
- Added a browser for Emacs info files: demo/stdwin/ibrowse
  (yes, I plan to put all STDWIN and Python documentation in texinfo
  form in the future)


5. Other changes to the distribution

- An Emacs Lisp file "python.el" is provided to facilitate editing
  Python programs in GNU Emacs (slightly improved since posted to
  gnu.emacs.sources)
- Some info on writing an extension in C is provided
- Some info on building Python on non-UNIX platforms is provided


=====================================
==> Release 0.9.1 (February 1991) <==
=====================================

- Micro changes only
- Added file "patchlevel.h"


=====================================
==> Release 0.9.0 (February 1991) <==
=====================================

Original posting to alt.sources.