Cython 0.23 发布，Python 的 C 语言扩展

Cython 0.23 发布，此版本相比第二个测试版本改进很小，还有一些 bug 修复。

https://pypi.python.org/pypi/Cython/0.23

此版本是个重要的特性版本，值得关注的改进如下：

* PEP 492 (async/await) 和 PEP 448 (star-unpacking generalizations)

* 内联生长器表达式

* 支持 C++ 分配和 bool() 操作符

* 支持覆盖分析

强烈建议更新，下载：

http://cython.org/

http://cython.org/release/Cython-0.23.tar.gz

http://cython.org/release/Cython-0.23.zip

SHA1 sums:

5a49123b39d89a20fb88bdc7886210

c39cdff695  Cython-0.23.tar.gz

9bec6c6df861be49ed608a0ab688b67bba543abe  Cython-0.23.zip

0.23 (2015-08-08)

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

新特性

--------------

* PEP 492 (async/await) was implemented.

See https://www.python.org/dev/peps/pep-0492/

* PEP 448 (Additional Unpacking Generalizations) was implemented.

See https://www.python.org/dev/peps/pep-0448/

* Support for coverage.py 4.0+ can be enabled by adding the plugin

"Cython.Coverage" to the ".coveragerc" config file.

* Annotated HTML source pages can integrate (XML) coverage reports.

* Tracing is supported in ``nogil`` functions/sections and module init

code.

* When generators are used in a Cython module and the module imports the

modules "inspect" and/or "asyncio", Cython enables interoperability by

patching these modules during the import to recognise Cython's internal

generator and coroutine types. This can be disabled by C compiling the

module with "-D CYTHON_PATCH_ASYNCIO=0" or "-D CYTHON_PATCH_INSPECT=0"

* When generators or coroutines are used in a Cython module, their types

are registered with the ``Generator`` and ``Coroutine`` ABCs in the

``collections`` or ``collections.abc`` stdlib module at import time to

enable interoperability with code that needs to detect and process Python

generators/coroutines.  These ABCs were added in CPython 3.5 and are

available for older Python versions through the ``backports_abc`` module

on PyPI.  See https://bugs.python.org/issue24018

* Adding/subtracting/dividing/modulus and equality comparisons with

constant Python floats and small integers are faster.

* Binary and/or/xor/rshift operations with small constant Python integers

are faster.

* When called on generator expressions, the builtins ``all()``, ``any()``,

``dict()``, ``list()``, ``set()``, ``sorted()`` and ``unicode.join()``

avoid the generator iteration overhead by inlining a part of their

functionality into the for-loop.

* Keyword argument dicts are no longer copied on function entry when they

are not being used or only passed through to other function calls (e.g.

in wrapper functions).

* The ``PyTypeObject`` declaration in ``cpython.object`` was extended.

* The builtin ``type`` type is now declared as PyTypeObject in source,

allowing for extern functions taking type parameters to have the correct

C signatures.  Note that this might break code that uses ``type`` just

for passing around Python types in typed variables.  Removing the type

declaration provides a backwards compatible fix.

* ``wraparound()`` and ``boundscheck()`` are available as no-ops in pure

Python mode.

* Const iterators were added to the provided C++ STL declarations.

* Smart pointers were added to the provided C++ STL declarations.

Patch by Daniel Filonik.

* ``NULL`` is allowed as default argument when embedding signatures.

This fixes ticket 843.

* When compiling with ``--embed``, the internal module name is changed to

``__main__`` to allow arbitrary program names, including those that would

be invalid for modules.  Note that this prevents reuse of the generated

C code as an importable module.

* External C++ classes that overload the assignment operator can be used.

Patch by Ian Henriksen.

* Support operator bool() for C++ classes so they can be used in

if-statements.

Bugs 修复

----------

* Calling "yield from" from Python on a Cython generator that returned a

value triggered a crash in CPython.  This is now being worked around.

See https://bugs.python.org/issue23996

* Language level 3 did not enable true division (a.k.a. float division)

for integer operands.

* Functions with fused argument types that included a generic 'object'

fallback could end up using that fallback also for other explicitly

listed object types.

* Relative cimports could accidentally fall back to trying an absolute

cimport on failure.

* The result of calling a C struct constructor no longer requires an

intermediate assignment when coercing to a Python dict.

* C++ exception declarations with mapping functions could fail to compile

when pre-declared in .pxd files.

* ``cpdef void`` methods are now permitted.

* ``abs(cint)`` could fail to compile in MSVC and used sub-optimal code

in C++.  Patch by David Vierra, original patch by Michael Enßlin.

* Buffer index calculations using index variables with small C integer

types could overflow for large buffer sizes.

Original patch by David Vierra.

* C unions use a saner way to coerce from and to Python dicts.

* When compiling a module ``foo.pyx``, the directories in ``sys.path``

are no longer searched when looking for ``foo.pxd``.

Patch by Jeroen Demeyer.

* Memory leaks in the embedding main function were fixed.

Original patch by Michael Enßlin.

* Some complex Python expressions could fail to compile inside of finally

clauses.

* Unprefixed 'str' literals were not supported as C varargs arguments.

* Fixed type errors in conversion enum types to/from Python.  Note that

this imposes stricter correctness requirements on enum declarations.

其他改进

-------------

* Changed mangling scheme in header files generated by ``cdef api``

declarations.

* Installation under CPython 3.3+ no longer requires a pass of the

2to3 tool.  This also makes it possible to run Cython in Python

3.3+ from a source checkout without installing it first.

Patch by Petr Viktorin.

* ``jedi-typer.py`` (in ``Tools/``) was extended and renamed to

``jedityper.py`` (to make it importable) and now works with and

requires Jedi 0.9.  Patch by Tzer-jen Wei.