=================
Features added
--------------
* New directives ``c_string_type`` and ``c_string_encoding`` to more easily
and automatically convert between C strings and the different Python string
types.
* The extension type flag ``Py_TPFLAGS_HAVE_VERSION_TAG`` is enabled by default
on extension types and can be disabled using the ``type_version_tag`` compiler
directive.
* EXPERIMENTAL support for simple Cython code level line tracing. Enabled by
the "linetrace" compiler directive.
* Cython implemented functions make their argument and return type annotations
available through the ``__annotations__`` attribute (PEP 3107).
* Access to non-cdef module globals and Python object attributes is faster.
* ``Py_UNICODE*`` coerces from and to Python unicode strings. This is
helpful when talking to Windows APIs, which use compatible wchar_t
arrays for strings. Note that the ``Py_UNICODE`` type is otherwise
deprecated as of CPython 3.3.
* ``isinstance(obj, basestring)`` is optimised. In Python 3 it only tests
for instances of ``str`` (i.e. Py2 ``unicode``).
* The ``basestring`` builtin is mapped to ``str`` (i.e. Py2 ``unicode``) when
compiling the generated C code under Python 3.
* Closures use freelists, which can speed up their creation quite substantially.
This is also visible for short running generator expressions, for example.
* A new class decorator ``cython.freelist(N)`` creates a static freelist of N
instances for an extension type, thus avoiding the costly allocation step if
possible. This can speed up object instantiation by 20-30% in suitable
scenarios. Note that freelists are currently only supported for base types,
not for types that inherit from others.
* Fast extension type instantiation using the ``Type.__new__(Type)`` idiom has
gained support for passing arguments. It is also a bit faster for types defined
inside of the module.
* The Python2-only dict methods ``.iter*()`` and ``.view*()`` (requires Python 2.7)
are automatically mapped to the equivalent keys/values/items methods in Python 3
for typed dictionaries.
* Slicing unicode strings, lists and tuples is faster.
* list.append() is faster on average.
* ``raise Exception() from None`` suppresses the exception context in Py3.3.
* Py3 compatible ``exec(tuple)`` syntax is supported in Py2 code.
* Keyword arguments are supported for cdef functions.
* External C++ classes can be declared nogil. Patch by John Stumpo. This fixes
trac ticket 805.
Bugs fixed
----------
* 2-value slicing of unknown objects passes the correct slice when the ``getitem``
protocol is used instead of the ``getslice`` protocol (especially in Python 3),
i.e. ``None`` values for missing bounds instead of ``[0,maxsize]``. It is also
a bit faster in some cases, e.g. for constant bounds. This fixes trac ticket 636.
* Cascaded assignments of None values to extension type variables failed with
a ``TypeError`` at runtime.
* The ``__defaults__`` attribute was not writable for Cython implemented
functions.
* Default values of keyword-only arguments showed up in ``__defaults__`` instead
of ``__kwdefaults__`` (which was not implemented). Both are available for
Cython implemented functions now, as specified in Python 3.x.
* ``yield`` works inside of ``with gil`` sections. It previously lead to a crash.
This fixes trac ticket 803.
* Static methods without explicitly named positional arguments (e.g. having only
``*args``) crashed when being called. This fixes trac ticket 804.
* ``dir()`` without arguments previously returned an unsorted list, which now
gets sorted as expected.
* ``dict.items()``, ``dict.keys()`` and ``dict.values()`` no longer return lists
in Python 3.
* Exiting from an ``except-as`` clause now deletes the exception in Python 3 mode.
* The declarations of ``frexp()`` and ``ldexp()`` in ``math.pxd`` were incorrect.
Other changes
-------------