Misc/NEWS

=====================================
==> 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 :-)