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Commit ba40fb46 authored by Andrew M. Kuchling's avatar Andrew M. Kuchling
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Last batch of edits; remove the 'other changes' section

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Doc/whatsnew/2.6.rst
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......@@ -67,6 +67,11 @@ such as the :mod:`multiprocessing` and :mod:`jsonlib` modules, but
there aren't many new features that aren't related to Python 3.0 in
some way.
Python 2.6 also sees a number of improvements and bugfixes throughout
the source. A search through the change logs finds there were XXX
patches applied and YYY bugs fixed between Python 2.5 and 2.6. Both
figures are likely to be underestimates.
This article doesn't attempt to provide a complete specification of
the new features, but instead provides a convenient overview. For
full details, you should refer to the documentation for Python 2.6. If
......@@ -2503,7 +2508,7 @@ changes, or look through the Subversion logs for all the details.
:meth:`activeCount` method is renamed to :meth:`active_count`. The
2.6 version of the module supports the same properties and renamed
methods, but doesn't remove the old methods. (Carried out by
various people, most notably Benjamin Peterson.)
several people, most notably Benjamin Peterson.)
The :mod:`threading` module's :class:`Thread` objects
gained an :attr:`ident` property that returns the thread's
......@@ -2619,11 +2624,12 @@ changes, or look through the Subversion logs for all the details.
The :mod:`ast` module
----------------------
The :mod:`ast` module provides an Abstract Syntax Tree representation
of Python code. For Python 2.6, Armin Ronacher contributed a set of
helper functions that perform various common tasks. These will be useful
for HTML templating packages, code analyzers, and similar tools that
process Python code.
The :mod:`ast` module provides an Abstract Syntax Tree
representation of Python code, and Armin Ronacher
contributed a set of helper functions that perform a variety of
common tasks. These will be useful for HTML templating
packages, code analyzers, and similar tools that process
Python code.
The :func:`parse` function takes an expression and returns an AST.
The :func:`dump` function outputs a representation of a tree, suitable
......@@ -2639,28 +2645,46 @@ for debugging::
""")
print ast.dump(t)
This outputs::
Module(body=[Assign(targets=[Name(id='d', ctx=Store())],
value=Dict(keys=[], values=[])), For(target=Name(id='i',
ctx=Store()), iter=Str(s='abcdefghijklm'),
body=[Assign(targets=[Subscript(value=Name(id='d', ctx=Load()),
slice=Index(value=BinOp(left=Name(id='i', ctx=Load()), op=Add(),
right=Name(id='i', ctx=Load()))), ctx=Store())],
value=BinOp(left=BinOp(left=Call(func=Name(id='ord', ctx=Load()),
args=[Name(id='i', ctx=Load())], keywords=[], starargs=None,
kwargs=None), op=Sub(), right=Call(func=Name(id='ord',
ctx=Load()), args=[Str(s='a')], keywords=[], starargs=None,
kwargs=None)), op=Add(), right=Num(n=1)))], orelse=[]),
Print(dest=None, values=[Name(id='d', ctx=Load())], nl=True)])
This outputs a deeply nested tree::
Module(body=[
Assign(targets=[
Name(id='d', ctx=Store())
], value=Dict(keys=[], values=[]))
For(target=Name(id='i', ctx=Store()),
iter=Str(s='abcdefghijklm'), body=[
Assign(targets=[
Subscript(value=
Name(id='d', ctx=Load()),
slice=
Index(value=
BinOp(left=Name(id='i', ctx=Load()), op=Add(),
right=Name(id='i', ctx=Load()))), ctx=Store())
], value=
BinOp(left=
BinOp(left=
Call(func=
Name(id='ord', ctx=Load()), args=[
Name(id='i', ctx=Load())
], keywords=[], starargs=None, kwargs=None),
op=Sub(), right=Call(func=
Name(id='ord', ctx=Load()), args=[
Str(s='a')
], keywords=[], starargs=None, kwargs=None)),
op=Add(), right=Num(n=1)))
], orelse=[])
Print(dest=None, values=[
Name(id='d', ctx=Load())
], nl=True)
])
The :func:`literal_eval` method takes a string or an AST
representing a literal expression, one that contains a Python
expression containing only strings, numbers, dictionaries, etc. but no
statements or function calls, and returns the resulting value. If you
need to unserialize an expression but need to worry about security
and can't risk using an :func:`eval` call, :func:`literal_eval` will
handle it safely::
representing a literal expression, parses and evaluates it, and
returns the resulting value. A literal expression is a Python
expression containing only strings, numbers, dictionaries,
etc. but no statements or function calls. If you need to
evaluate an expression but accept the security risk of using an
:func:`eval` call, :func:`literal_eval` will handle it safely::
>>> literal = '("a", "b", {2:4, 3:8, 1:2})'
>>> print ast.literal_eval(literal)
......@@ -2680,7 +2704,7 @@ numbers.
The :mod:`future_builtins` module
--------------------------------------
Python 3.0 makes various changes to the repertoire of built-in
Python 3.0 makes many changes to the repertoire of built-in
functions, and most of the changes can't be introduced in the Python
2.x series because they would break compatibility.
The :mod:`future_builtins` module provides versions
......@@ -2695,17 +2719,18 @@ The functions in this module currently include:
* ``filter(*predicate*, *iterable*)``,
``map(*func*, *iterable1*, ...)``: the 3.0 versions
return iterators, differing from the 2.x built-ins that return lists.
return iterators, unlike the 2.x built-ins which return lists.
* ``hex(*value*)``, ``oct(*value*)``: instead of calling the
:meth:`__hex__` or :meth:`__oct__` methods, these versions will
call the :meth:`__index__` method and convert the result to hexadecimal
or octal.
or octal. :func:`oct` will use the new ``0o`` notation for its
result.
.. ======================================================================
The :mod:`json` module
----------------------
The :mod:`json` module: JavaScript Object Notation
--------------------------------------------------------------------
The new :mod:`json` module supports the encoding and decoding of Python types in
JSON (Javascript Object Notation). JSON is a lightweight interchange format
......@@ -2723,21 +2748,22 @@ types. The following example encodes and decodes a dictionary::
>>> json.loads(in_json) # Decode into a Python object
{"spam" : "foo", "parrot" : 42}
It is also possible to write your own decoders and encoders to support more
types. Pretty-printing of the JSON strings is also supported.
It's also possible to write your own decoders and encoders to support
more types. Pretty-printing of the JSON strings is also supported.
:mod:`json` (originally called simplejson) was written by Bob Ippolito.
:mod:`json` (originally called simplejson) was written by Bob
Ippolito.
.. ======================================================================
plistlib: A Property-List Parser
The :mod:`plistlib` module: A Property-List Parser
--------------------------------------------------
A commonly-used format on MacOS X is the ``.plist`` format,
which stores basic data types (numbers, strings, lists,
and dictionaries) and serializes them into an XML-based format.
(It's a lot like the XML-RPC serialization of data types.)
The ``.plist`` format is commonly used on MacOS X to
store basic data types (numbers, strings, lists,
and dictionaries) by serializing them into an XML-based format.
It resembles the XML-RPC serialization of data types.
Despite being primarily used on MacOS X, the format
has nothing Mac-specific about it and the Python implementation works
......@@ -2753,7 +2779,7 @@ Using the module is simple::
# Create data structure
data_struct = dict(lastAccessed=datetime.datetime.now(),
version=1,
categories=('Personal', 'Shared', 'Private'))
categories=('Personal','Shared','Private'))
# Create string containing XML.
plist_str = plistlib.writePlistToString(data_struct)
......@@ -2798,13 +2824,13 @@ A new calling convention tells :mod:`ctypes` to clear the ``errno`` or
Win32 LastError variables at the outset of each wrapped call.
(Implemented by Thomas Heller; :issue:`1798`.)
For the Unix ``errno`` variable: when creating a wrapped function,
you can supply ``use_errno=True`` as a keyword parameter
to the :func:`DLL` function
and then call the module-level methods :meth:`set_errno`
and :meth:`get_errno` to set and retrieve the error value.
You can now retrieve the Unix ``errno`` variable after a function
call. When creating a wrapped function, you can supply
``use_errno=True`` as a keyword parameter to the :func:`DLL` function
and then call the module-level methods :meth:`set_errno` and
:meth:`get_errno` to set and retrieve the error value.
The Win32 LastError variable is supported similarly by
The Win32 LastError variable is similarly supported by
the :func:`DLL`, :func:`OleDLL`, and :func:`WinDLL` functions.
You supply ``use_last_error=True`` as a keyword parameter
and then call the module-level methods :meth:`set_last_error`
......@@ -2820,15 +2846,15 @@ Improved SSL Support
--------------------------------------------------
Bill Janssen made extensive improvements to Python 2.6's support for
the Secure Sockets Layer by adding a new module, :mod:`ssl`, on top of
the `OpenSSL <http://www.openssl.org/>`__ library. This new module
provides more control over the protocol negotiated, the X.509
certificates used, and has better support for writing SSL servers (as
opposed to clients) in Python. The existing SSL support in the
:mod:`socket` module hasn't been removed and continues to work,
the Secure Sockets Layer by adding a new module, :mod:`ssl`, that's
built atop the `OpenSSL <http://www.openssl.org/>`__ library.
This new module provides more control over the protocol negotiated,
the X.509 certificates used, and has better support for writing SSL
servers (as opposed to clients) in Python. The existing SSL support
in the :mod:`socket` module hasn't been removed and continues to work,
though it will be removed in Python 3.0.
To use the new module, first you must create a TCP connection in the
To use the new module, you must first create a TCP connection in the
usual way and then pass it to the :func:`ssl.wrap_socket` function.
It's possible to specify whether a certificate is required, and to
obtain certificate info by calling the :meth:`getpeercert` method.
......@@ -2845,9 +2871,15 @@ Build and C API Changes
Changes to Python's build process and to the C API include:
* Python 2.6 can be built with Microsoft Visual Studio 2008.
See the :file:`PCbuild9` directory for the build files.
(Implemented by Christian Heimes.)
* Python now must be compiled with C89 compilers (after 19
years!). This means that the Python source tree has dropped its
own implementations of :cfunc:`memmove` and :cfunc:`strerror`, which
are in the C89 standard library.
* Python 2.6 can be built with Microsoft Visual Studio 2008 (version
9.0), and this is the new default compiler. See the
:file:`PCbuild` directory for the build files. (Implemented by
Christian Heimes.)
* On MacOS X, Python 2.6 can be compiled as a 4-way universal build.
The :program:`configure` script
......@@ -2856,11 +2888,6 @@ Changes to Python's build process and to the C API include:
architectures (x86, PowerPC), 64-bit (x86-64 and PPC-64), or both.
(Contributed by Ronald Oussoren.)
* Python now can only be compiled with C89 compilers (after 19
years!). This means that the Python source tree can now drop its
own implementations of :cfunc:`memmove` and :cfunc:`strerror`, which
are in the C89 standard library.
* The BerkeleyDB module now has a C API object, available as
``bsddb.db.api``. This object can be used by other C extensions
that wish to use the :mod:`bsddb` module for their own purposes.
......@@ -2889,14 +2916,14 @@ Changes to Python's build process and to the C API include:
function, :cfunc:`PyImport_ImportModuleNoBlock`, will look for a
module in ``sys.modules`` first, then try to import it after
acquiring an import lock. If the import lock is held by another
thread, the :exc:`ImportError` is raised.
thread, an :exc:`ImportError` is raised.
(Contributed by Christian Heimes.)
* Several functions return information about the platform's
floating-point support. :cfunc:`PyFloat_GetMax` returns
the maximum representable floating point value,
and :cfunc:`PyFloat_GetMin` returns the minimum
positive value. :cfunc:`PyFloat_GetInfo` returns a dictionary
positive value. :cfunc:`PyFloat_GetInfo` returns an object
containing more information from the :file:`float.h` file, such as
``"mant_dig"`` (number of digits in the mantissa), ``"epsilon"``
(smallest difference between 1.0 and the next largest value
......@@ -2939,7 +2966,7 @@ Changes to Python's build process and to the C API include:
internal free lists of objects that can be re-used. The data
structures for these free lists now follow a naming convention: the
variable is always named ``free_list``, the counter is always named
``numfree``, and a macro :cmacro:`Py<typename>_MAXFREELIST` is
``numfree``, and a macro ``Py<typename>_MAXFREELIST`` is
always defined.
* A new Makefile target, "make check", prepares the Python source tree
......@@ -2963,6 +2990,14 @@ Port-Specific Changes: Windows
* The support for Windows 95, 98, ME and NT4 has been dropped.
Python 2.6 requires at least Windows 2000 SP4.
* The new default compiler on Windows is Visual Studio 2008 (version
9.0). The build directories for Visual Studio 2003 (version 7.1) and
2005 (version 8.0) were moved into the PC/ directory. The new
:file:`PCbuild` directory supports cross compilation for X64, debug
builds and Profile Guided Optimization (PGO). PGO builds are roughly
10% faster than normal builds. (Contributed by Christian Heimes
with help from Amaury Forgeot d'Arc and Martin von Loewis.)
* The :mod:`msvcrt` module now supports
both the normal and wide char variants of the console I/O
API. The :func:`getwch` function reads a keypress and returns a Unicode
......@@ -2970,9 +3005,9 @@ Port-Specific Changes: Windows
takes a Unicode character and writes it to the console.
(Contributed by Christian Heimes.)
* :func:`os.path.expandvars` will now expand environment variables
in the form "%var%", and "~user" will be expanded into the
user's home directory path. (Contributed by Josiah Carlson.)
* :func:`os.path.expandvars` will now expand environment variables in
the form "%var%", and "~user" will be expanded into the user's home
directory path. (Contributed by Josiah Carlson; :issue:`957650`.)
* The :mod:`socket` module's socket objects now have an
:meth:`ioctl` method that provides a limited interface to the
......@@ -2996,14 +3031,6 @@ Port-Specific Changes: Windows
return field values as an integer or a string.
(Contributed by Floris Bruynooghe; :issue:`2125`.)
* The new default compiler on Windows is Visual Studio 2008 (VS 9.0). The
build directories for Visual Studio 2003 (VS7.1) and 2005 (VS8.0)
were moved into the PC/ directory. The new PCbuild directory supports
cross compilation for X64, debug builds and Profile Guided Optimization
(PGO). PGO builds are roughly 10% faster than normal builds.
(Contributed by Christian Heimes with help from Amaury Forgeot d'Arc and
Martin von Loewis.)
.. ======================================================================
Port-Specific Changes: MacOS X
......@@ -3089,32 +3116,6 @@ be removed in Python 3.0:
:mod:`videoreader`, and
:mod:`WAIT`.
.. ======================================================================
.. _section-other:
Other Changes and Fixes
=======================
As usual, there were a bunch of other improvements and bugfixes
scattered throughout the source tree. A search through the change
logs finds there were XXX patches applied and YYY bugs fixed between
Python 2.5 and 2.6. Both figures are likely to be underestimates.
Some of the more notable changes are:
* It's now possible to prevent Python from writing any :file:`.pyc`
or :file:`.pyo` files by either supplying the :option:`-B` switch
or setting the :envvar:`PYTHONDONTWRITEBYTECODE` environment variable
to any non-empty string when running the Python interpreter. These
are also used to set the :data:`sys.dont_write_bytecode` attribute;
Python code can change this variable to control whether bytecode
files are subsequently written.
(Contributed by Neal Norwitz and Georg Brandl.)
.. ======================================================================
......
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