0.21.1 (2014-10-18)
===================
Features added
--------------
* New ``cythonize`` option ``-a`` to generate the annotated HTML source view.
* Missing C-API declarations in ``cpython.unicode`` were added.
* Passing ``language='c++'`` into cythonize() globally enables C++ mode for
all modules that were not passed as Extension objects (i.e. only source
files and file patterns).
* ``Py_hash_t`` is a known type (used in CPython for hash values).
* ``PySlice_*()`` C-API functions are available from the ``cpython.slice``
module.
* Allow arrays of C++ classes.
Bugs fixed
----------
* Reference leak for non-simple Python expressions in boolean and/or expressions.
* To fix a name collision and to reflect availability on host platforms,
standard C declarations [ clock(), time(), struct tm and tm* functions ]
were moved from posix/time.pxd to a new libc/time.pxd. Patch by Charles
Blake.
* Rerunning unmodified modules in IPython's cython support failed.
Patch by Matthias Bussonier.
* Casting C++ ``std::string`` to Python byte strings failed when
auto-decoding was enabled.
* Fatal exceptions in global module init code could lead to crashes
if the already created module was used later on (e.g. through a
stale reference in sys.modules or elsewhere).
* ``cythonize.py`` script was not installed on MS-Windows.
Other changes
-------------
* Compilation no longer fails hard when unknown compilation options are
passed. Instead, it raises a warning and ignores them (as it did silently
before 0.21). This will be changed back to an error in a future release.
0.21 (2014-09-10)
=================
Features added
--------------
* C (cdef) functions allow inner Python functions.
* Enums can now be declared as cpdef to export their values to
the module's Python namespace. Cpdef enums in pxd files export
their values to their own module, iff it exists.
* Allow @staticmethod decorator to declare static cdef methods.
This is especially useful for declaring "constructors" for
cdef classes that can take non-Python arguments.
* Taking a ``char*`` from a temporary Python string object is safer
in more cases and can be done inside of non-trivial expressions,
including arguments of a function call. A compile time error
is raised only when such a pointer is assigned to a variable and
would thus exceed the lifetime of the string itself.
* Generators have new properties ``__name__`` and ``__qualname__``
that provide the plain/qualified name of the generator function
(following CPython 3.5). See http://bugs.python.org/issue21205
* The ``inline`` function modifier is available as a decorator
``@cython.inline`` in pure mode.
* When cygdb is run in a virtualenv, it enables the same virtualenv
inside of the debugger. Patch by Marc Abramowitz.
* PEP 465: dedicated infix operator for matrix multiplication (A @ B).
* HTML output of annotated code uses Pygments for code highlighting
and generally received a major overhaul by Matthias Bussonier.
* IPython magic support is now available directly from Cython with
the command "%load_ext cython". Cython code can directly be
executed in a cell when marked with "%%cython". Code analysis
is available with "%%cython -a". Patch by Martín Gaitán.
* Simple support for declaring Python object types in Python signature
annotations. Currently requires setting the compiler directive
``annotation_typing=True``.
* New directive ``use_switch`` (defaults to True) to optionally disable
the optimization of chained if statement to C switch statements.
* Defines dynamic_cast et al. in ``libcpp.cast`` and C++ heap data
structure operations in ``libcpp.algorithm``.
* Shipped header declarations in ``posix.*`` were extended to cover
more of the POSIX API. Patches by Lars Buitinck and Mark Peek.
Optimizations
-------------
* Simple calls to C implemented Python functions/methods are faster.
This also speeds up many operations on builtins that Cython cannot
otherwise optimise.
* The "and"/"or" operators try to avoid unnecessary coercions of their
arguments. They now evaluate the truth value of each argument
independently and only coerce the final result of the whole expression
to the target type (e.g. the type on the left side of an assignment).
This also avoids reference counting overhead for Python values during
evaluation and generally improves the code flow in the generated C code.
* The Python expression "2 ** N" is optimised into bit shifting.
See http://bugs.python.org/issue21420
* Cascaded assignments (a = b = ...) try to minimise the number of
type coercions.
* Calls to ``slice()`` are translated to a straight C-API call.
Bugs fixed
----------
* Crash when assigning memory views from ternary conditional expressions.
* Nested C++ templates could lead to unseparated ">>" characters being
generated into the C++ declarations, which older C++ compilers could
not parse.
* Sending SIGINT (Ctrl-C) during parallel cythonize() builds could
hang the child processes.
* No longer ignore local setup.cfg files for distutils in pyximport.
Patch by Martin Teichmann.
* Taking a ``char*`` from an indexed Python string generated unsafe
reference counting code.
* Set literals now create all of their items before trying to add them
to the set, following the behaviour in CPython. This makes a
difference in the rare case that the item creation has side effects
and some items are not hashable (or if hashing them has side effects,
too).
* Cython no longer generates the cross product of C functions for code
that uses memory views of fused types in function signatures (e.g.
``cdef func(floating[:] a, floating[:] b)``). This is considered the
expected behaviour by most users and was previously inconsistent with
other structured types like C arrays. Code that really wants all type
combinations can create the same fused memoryview type under different
names and use those in the signature to make it clear which types are
independent.
* Names that were unknown at compile time were looked up as builtins at
runtime but not as global module names. Trying both lookups helps with
globals() manipulation.
* Fixed stl container conversion for typedef element types.
* ``obj.pop(x)`` truncated large C integer values of x to ``Py_ssize_t``.
* ``__init__.pyc`` is recognised as marking a package directory
(in addition to .py, .pyx and .pxd).
* Syntax highlighting in ``cython-mode.el`` for Emacs no longer
incorrectly highlights keywords found as part of longer names.
* Correctly handle ``from cython.submodule cimport name``.
* Fix infinite recursion when using super with cpdef methods.
* No-args ``dir()`` was not guaranteed to return a sorted list.
Other changes
-------------
* The header line in the generated C files no longer contains the
timestamp but only the Cython version that wrote it. This was
changed to make builds more reproducible.
* Removed support for CPython 2.4, 2.5 and 3.1.
* The licensing implications on the generated code were clarified
to avoid legal constraints for users.
0.20.2 (2014-06-16)
===================
Features added
--------------
* Some optimisations for set/frozenset instantiation.
* Support for C++ unordered_set and unordered_map.
Bugs fixed
----------
* Access to attributes of optimised builtin methods (e.g.
``[].append.__name__``) could fail to compile.
* Memory leak when extension subtypes add a memory view as attribute
to those of the parent type without having Python object attributes
or a user provided dealloc method.
* Compiler crash on readonly properties in "binding" mode.
* Auto-encoding with ``c_string_encoding=ascii`` failed in Py3.3.
* Crash when subtyping freelist enabled Cython extension types with
Python classes that use ``__slots__``.
* Freelist usage is restricted to CPython to avoid problems with other
Python implementations.
* Memory leak in memory views when copying overlapping, contiguous slices.
* Format checking when requesting non-contiguous buffers from
``cython.array`` objects was disabled in Py3.
* C++ destructor calls in extension types could fail to compile in clang.
* Buffer format validation failed for sequences of strings in structs.
* Docstrings on extension type attributes in .pxd files were rejected.
===================
0.20.1 (2014-02-11)
===================
Bugs fixed
----------
* List/Tuple literals multiplied by more than one factor were only multiplied
by the last factor instead of all.
* Lookups of special methods (specifically for context managers) could fail
in Python <= 2.6/3.1.
* Local variables were erroneously appended to the signature introspection
of Cython implemented functions with keyword-only arguments under Python 3.
* In-place assignments to variables with inferred Python builtin/extension
types could fail with type errors if the result value type was incompatible
with the type of the previous value.
* The C code generation order of cdef classes, closures, helper code,
etc. was not deterministic, thus leading to high code churn.
* Type inference could fail to deduce C enum types.
* Type inference could deduce unsafe or inefficient types from integer
assignments within a mix of inferred Python variables and integer
variables.
completely and adapting the package.
Replace patch-aa with post-install target.
Fix interpreter path in installed file.
Bump PKGREVISION.
Addresses PR pkg/48602 by Hauke Fath.
0.20 (??)
===================
Features added
--------------
* Support for CPython 3.4.
* Support for calling C++ template functions.
* ``yield`` is supported in ``finally`` clauses.
* The C code generated for finally blocks is duplicated for each exit
case to allow for better optimisations by the C compiler.
* Cython tries to undo the Python optimisationism of assigning a bound
method to a local variable when it can generate better code for the
direct call.
* Constant Python float values are cached.
* String equality comparisons can use faster type specific code in
more cases than before.
* String/Unicode formatting using the '%' operator uses a faster
C-API call.
* ``bytearray`` has become a known type and supports coercion from and
to C strings. Indexing, slicing and decoding is optimised. Note that
this may have an impact on existing code due to type inference.
* Using ``cdef basestring stringvar`` and function arguments typed as
``basestring`` is now meaningful and allows assigning exactly
``str`` and ``unicode`` objects, but no subtypes of these types.
* Support for the ``__debug__`` builtin.
* Assertions in Cython compiled modules are disabled if the running
Python interpreter was started with the "-O" option.
* Some types that Cython provides internally, such as functions and
generators, are now shared across modules if more than one Cython
implemented module is imported.
* The type inference algorithm works more fine granular by taking the
results of the control flow analysis into account.
* A new script in ``bin/cythonize`` provides a command line frontend
to the cythonize() compilation function (including distutils build).
* The new extension type decorator ``@cython.no_gc_clear`` prevents
objects from being cleared during cyclic garbage collection, thus
making sure that object attributes are kept alive until deallocation.
* During cyclic garbage collection, attributes of extension types that
cannot create reference cycles due to their type (e.g. strings) are
no longer considered for traversal or clearing. This can reduce the
processing overhead when searching for or cleaning up reference cycles.
* Package compilation (i.e. ``__init__.py`` files) now works, starting
with Python 3.3.
* The cython-mode.el script for Emacs was updated. Patch by Ivan Andrus.
* An option common_utility_include_dir was added to cythonize() to save
oft-used utility code once in a separate directory rather than as
part of each generated file.
* ``unraisable_tracebacks`` directive added to control printing of
tracebacks of unraisable exceptions.
Bugs fixed
----------
* Abstract Python classes that subtyped a Cython extension type
failed to raise an exception on instantiation, and thus ended
up being instantiated.
* ``set.add(a_tuple)`` and ``set.discard(a_tuple)`` failed with a
TypeError in Py2.4.
* The PEP 3155 ``__qualname__`` was incorrect for nested classes and
inner classes/functions declared as ``global``.
* Several corner cases in the try-finally statement were fixed.
* The metaclass of a Python class was not inherited from its parent
class(es). It is now extracted from the list of base classes if not
provided explicitly using the Py3 ``metaclass`` keyword argument.
In Py2 compilation mode, a ``__metaclass__`` entry in the class
dict will still take precedence if not using Py3 metaclass syntax,
but only *after* creating the class dict (which may have been done
by a metaclass of a base class, see PEP 3115). It is generally
recommended to use the explicit Py3 syntax to define metaclasses
for Python types at compile time.
* The automatic C switch statement generation behaves more safely for
heterogeneous value types (e.g. mixing enum and char), allowing for
a slightly wider application and reducing corner cases. It now always
generates a 'default' clause to avoid C compiler warnings about
unmatched enum values.
* Fixed a bug where class hierarchies declared out-of-order could result
in broken generated code.
* Fixed a bug which prevented overriding const methods of C++ classes.
* Fixed a crash when converting Python objects to C++ strings fails.
Other changes
-------------
* In Py3 compilation mode, Python2-style metaclasses declared by a
``__metaclass__`` class dict entry are ignored.
* In Py3.4+, the Cython generator type uses ``tp_finalize()`` for safer
cleanup instead of ``tp_del()``.
either because they themselves are not ready or because a
dependency isn't. This is annotated by
PYTHON_VERSIONS_INCOMPATIBLE= 33 # not yet ported as of x.y.z
or
PYTHON_VERSIONS_INCOMPATIBLE= 33 # py-foo, py-bar
respectively, please use the same style for other packages,
and check during updates.
Use versioned_dependencies.mk where applicable.
Use REPLACE_PYTHON instead of handcoded alternatives, where applicable.
Reorder Makefile sections into standard order, where applicable.
Remove PYTHON_VERSIONS_INCLUDE_3X lines since that will be default
with the next commit.
Whitespace cleanups and other nits corrected, where necessary.
0.19.2 (2013-10-13)
===================
Bugs fixed
----------
* Some standard declarations were fixed or updated, including the previously
incorrect declaration of ``PyBuffer_FillInfo()`` and some missing bits in
``libc.math``.
* Heap allocated subtypes of ``type`` used the wrong base type struct at the
C level.
* Calling the unbound method dict.keys/value/items() in dict subtypes could
call the bound object method instead of the unbound supertype method.
* "yield" wasn't supported in "return" value expressions.
* Using the "bint" type in memory views lead to unexpected results.
It is now an error.
* Assignments to global/closure variables could catch them in an illegal state
while deallocating the old value.
0.19.1 (2013-05-11)
===================
Features added
--------------
* Completely empty C-API structs for extension type slots (protocols like
number/mapping/sequence) are no longer generated into the C code.
* Docstrings that directly follow a public/readonly attribute declaration
in a cdef class will be used as docstring of the auto-generated property.
This fixes ticket 206.
* The automatic signature documentation tries to preserve more semantics
of default arguments and argument types. Specifically, ``bint`` arguments
now appear as type ``bool``.
* A warning is emitted when negative literal indices are found inside of
a code section that disables ``wraparound`` handling. This helps with
fixing invalid code that might fail in the face of future compiler
optimisations.
* Constant folding for boolean expressions (and/or) was improved.
* Added a build_dir option to cythonize() which allows one to place
the generated .c files outside the source tree.
Bugs fixed
----------
* ``isinstance(X, type)`` failed to get optimised into a call to
``PyType_Check()``, as done for other builtin types.
* A spurious "from datetime cimport *" was removed from the "cpython"
declaration package. This means that the "datetime" declarations
(added in 0.19) are no longer available directly from the "cpython"
namespace, but only from "cpython.datetime". This is the correct
way of doing it because the declarations refer to a standard library
module, not the core CPython C-API itself.
* The C code for extension types is now generated in topological order
instead of source code order to avoid C compiler errors about missing
declarations for subtypes that are defined before their parent.
* The ``memoryview`` type name no longer shows up in the module dict of
modules that use memory views. This fixes trac ticket 775.
* Regression in 0.19 that rejected valid C expressions from being used
in C array size declarations.
* In C++ mode, the C99-only keyword ``restrict`` could accidentally be
seen by the GNU C++ compiler. It is now specially handled for both
GCC and MSVC.
* Testing large (> int) C integer values for their truth value could fail
due to integer wrap-around.
Other changes
-------------
0.19 (2013-04-19)
=================
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.
* 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.
* 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
----------
* 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.
0.18 (2013-01-28)
=================
Features added
--------------
* Named Unicode escapes ("\N{...}") are supported.
* Python functions/classes provide the special attribute "__qualname__"
as defined by PEP 3155.
* Added a directive ``overflowcheck`` which raises an OverflowException when
arithmetic with C ints overflow. This has a modest performance penalty, but
is much faster than using Python ints.
* Calls to nested Python functions are resolved at compile time.
* Type inference works across nested functions.
* ``py_bytes_string.decode(...)`` is optimised.
* C ``const`` declarations are supported in the language.
Bugs fixed
----------
* Automatic C++ exception mapping didn't work in nogil functions (only in
"with nogil" blocks).
0.17.4 (2013-01-03)
===================
Bugs fixed
----------
* Garbage collection triggered during deallocation of container classes could lead to a double-deallocation.
0.17.3:
Bugs fixed
----------
* During final interpreter cleanup (with types cleanup enabled at compile
time), extension types that inherit from base types over more than one
level that were cimported from other modules could lead to a crash.
* Weak-reference support in extension types (with a "cdef __weakref__"
attribute) generated incorrect deallocation code.
* In CPython 3.3, converting a Unicode character to the Py_UNICODE type
could fail to raise an overflow for non-BMP characters that do not fit
into a wchar_t on the current platform.
* Negative C integer constants lost their longness suffix in the generated
C code.
0.17.2:
Features added
--------------
* ``cythonize()`` gained a best effort compile mode that can be used to
simply ignore .py files that fail to compile.
Bugs fixed
----------
* Replacing an object reference with the value of one of its cdef
attributes could generate incorrect C code that accessed the object after
deleting its last reference.
* C-to-Python type coercions during cascaded comparisons could generate
invalid C code, specifically when using the 'in' operator.
* "obj[1,]" passed a single integer into the item getter instead of a tuple.
* Cyclic imports at module init time did not work in Py3.
* The names of C++ destructors for template classes were built incorrectly.
* In pure mode, type casts in Cython syntax and the C ampersand operator
are now rejected. Use the pure mode replacements instead.
* In pure mode, C type names and the sizeof() function are no longer
recognised as such and can be used as normal Python names.
* The extended C level support for the CPython array type was declared too
late to be used by user defined classes.
* C++ class nesting was broken.
* Better checking for required nullary constructors for stack-allocated C++
instances.
* Remove module docstring in no-docstring mode.
* Fix specialization for varargs function signatures.
* Fix several compiler crashes.
0.17.1:
General Improvements and Bug Fixes
A reference leak was fixed in the new dict iteration code when
the loop target was not a plain variable but an unpacked tuple.
Memory views did not handle the special case of a NULL buffer
strides value, as allowed by PEP3118.
0.17:
Features
Alpha quality support for compiling and running Cython generated
extension modules in PyPy (through cpyext). Note that this
requires at leastPyPy 1.9 and in many cases also adaptations
in user code, especially to avoid borrowed references when no
owned reference is being held directly in C space (a reference
in a Python list or dict is not enough, for example). See the
documentation on porting Cython code to PyPy.
"yield from" is supported (PEP 380) and a couple of minor
problems with generators were fixed.
C++ STL container classes automatically coerce from and to the
equivalent Python container types on typed assignments and
casts. Usage examples are here. Note that the data in the
containers is copied during this conversion.
C++ iterators can now be iterated over using for x in cpp_container
whenever cpp_container has begin() and end() methods returning
objects satisfying the iterator pattern (that is, it can be
incremented, dereferenced, and compared (for non-equality)).
cdef classes can now have C++ class members (provided a
zero-argument constructor exists)
A new cpython.array standard cimport file allows to efficiently
talk to the stdlib array.array data type in Python 2. Since
CPython does not export an official C-API for this module, it
receives special casing by the compiler in order to avoid setup
overhead on user side. In Python 3, both buffers and memory
views on the array type already worked out of the box with
earlier versions of Cython due to the native support for the
buffer interface in the Py3 array module.
Fast dict iteration is now enabled optimistically also for
untyped variables when the common iteration methods are used.
The unicode string processing code was adapted for the upcoming
CPython 3.3 (PEP 393, new Unicode buffer layout).
Buffer arguments and memory view arguments in Python functions
can be declared "not None" to raise a TypeError on None input.
c(p)def functions in pure mode can specify their return type
with "@cython.returns()".
Automatic dispatch for fused functions with memoryview arguments
Support newaxis indexing for memoryviews
Support decorators for fused functions
General Improvements and Bug Fixes
Old-style Py2 imports did not work reliably in Python 3.x and
were broken in Python 3.3. Regardless of this fix, it's generally
best to be explicit about relative and global imports in Cython
code because old-style imports have a higher overhead. To this
end, "from __future__ import absolute_import" is supported in
Python/Cython 2.x code now (previous versions of Cython already
used it when compiling Python 3 code).
Stricter constraints on the inline and final modifiers. If your
code does not compile due to this change, chances are these
modifiers were previously being ignored by the compiler and
can be removed without any performance regression.
Exceptions are always instantiated while raising them (as in
Python), instead of risking to instantiate them in potentially
unsafe situations when they need to be handled or otherwise
processed.
locals() properly ignores names that do not have Python compatible
types (including automatically inferred types).
Some garbage collection issues of memory views were fixed.
User declared char* types are now recognised as such and
auto-coerce to and from Python bytes strings.
libc.string provides a convenience declaration for const uchar
in addition to const char.
Modules generated by @cython.inline() are written into the
directory pointed to by the environment variable CYTHON_CACHE_DIR
if set.
numpy.pxd compiles in Python 3 mode.
callable() and next() compile to more efficient C code.
list.append() is faster on average.
Several C compiler warnings were fixed.
Several bugs related to memoryviews and fused types were fixed.
Several bug-fixes and improvements related to cythonize(),
including ccache-style caching.
0.16
Features
Enhancements to Cython's function type (support for weak
references, default arguments, code objects, dynamic attributes,
classmethods, staticmethods, and more)
Fused Types - Template-like support for functions and methods
CEP 522 (docs)
Typed views on memory - Support for efficient direct and indirect
buffers (indexing, slicing, transposing, ...) CEP 517 (docs)
super() without arguments
Final cdef methods (which translate into direct calls on known
instances)
General Improvements and Bug Fixes
support default arguments for closures
search sys.path for pxd files
support C++ template casting
faster traceback building and faster generator termination
support inplace operators on indexed buffers
fix alignment handling for record types in buffer support
allow nested prange sections
0.15.1
This is a bugfix-only release.
0.15
Major Features
Generators (yield) - Cython has full support for generators,
generator expressions and PEP 342 coroutines.
The nonlocal keyword is supported.
Re-acquiring the gil: with gil - works as expected within a
nogil context.
OpenMP support: prange.
Control flow analysis prunes dead code and emits warnings and
errors about uninitialised variables.
Debugger command cy set to assign values of expressions to
Cython variables and cy exec counterpart $cy_eval().
Exception chaining PEP 3134.
Relative imports PEP 328.
Improved pure syntax including cython.cclass, cython.cfunc,
and cython.ccall.
The with statement has its own dedicated and faster C
implementation.
Support for del.
Boundschecking directives implemented for builtin Python sequence
types.
Several updates and additions to the shipped standard library
.pxd files.
Forward declaration of types is no longer required for circular
references.
Note: this will be the last release to support Python 2.3; Python
2.4 will be supported for at least one more release.
General improvements and bug fixes
This release contains over a thousand commits including hundreds
of bugfixes and optimizations. The bug tracker has not been as
heavily used this release cycle, but is still an interesting subset
of improvements and fixes
Incompatible changes
Uninitialized variables are no longer initialized to None and
accessing them has the same semantics as standard Python.
globals() now returns a read-only dict of the Cython module's
globals, rather than the globals
of the first non-Cython module in the stack
Many C++ exceptions are now special cased to give closer Python
counterparts. This means that except+ functions that formerly
raised generic RuntimeErrors may raise something else such as
ArithmeticError.
Known regressions
The inlined generator expressions (introduced in Cython 0.13)
were disabled in favour of full generator expression support.
This breaks code that previously used them inside of cdef
functions (usage in def functions continues to work) and induces
a performance regression for cases that continue to work but
that were previously inlined. We hope to reinstate this feature
in the near future.
Generators (yield) - Cython has full support for generators,
generator expressions and PEP 342 coroutines.
The nonlocal keyword is supported.
Re-acquiring the gil: with gil - works as expected within a
nogil context.
OpenMP support: prange.
Control flow analysis prunes dead code and emits warnings and
errors about uninitialised variables.
Debugger command cy set to assign values of expressions to
Cython variables and cy exec counterpart $cy_eval().
Exception chaining PEP 3134.
Relative imports PEP 328.
Improved pure syntax including cython.cclass, cython.cfunc,
and cython.ccall.
The with statement has its own dedicated and faster C
implementation.
Support for del.
Boundschecking directives implemented for builtin Python sequence
types.
Several updates and additions to the shipped standard library
.pxd files.
Forward declaration of types is no longer required for circular
references.
Note: this will be the last release to support Python 2.3; Python
2.4 will be supported for at least one more release.
General improvements and bug fixes
This release contains over a thousand commits including hundreds
of bugfixes and optimizations. The bug tracker has not been as
heavily used this release cycle, but is still an interesting subset
of improvements and fixes
Incompatible changes
Uninitialized variables are no longer initialized to None and
accessing them has the same semantics as standard Python.
globals() now returns a read-only dict of the Cython module's
globals, rather than the globals
of the first non-Cython module in the stack
Many C++ exceptions are now special cased to give closer Python
counterparts. This means that except+ functions that formerly
raised generic RuntimeErrors may raise something else such as
ArithmeticError.
Known regressions
The inlined generator expressions (introduced in Cython 0.13)
were disabled in favour of full generator expression support.
This breaks code that previously used them inside of cdef
functions (usage in def functions continues to work) and induces
a performance regression for cases that continue to work but
that were previously inlined. We hope to reinstate this feature
in the near future.
0.14.1
New Features
The gdb debugging support was extended to include all major
Cython features, including closures.
raise MemoryError() is now safe to use as Cython replaces it
with the correct C-API call.
General improvements and bug fixes
The bug tracker has a list of the major improvements and fixes
Incompatible changes
Decorators on special methods of cdef classes now raise a
compile time error rather than being ignored.
In Python 3 language level mode (-3 option), the 'str' type is
now mapped to 'unicode', so that cdef str s declares a Unicode
string even when running in Python 2.
0.14
New Features
Python classes can now be nested and receive a proper closure
at definition time.
Redefinition is supported for Python functions, even within
the same scope.
Lambda expressions are supported in class bodies and at the
module level.
Metaclasses are supported for Python classes, both in Python
2 and Python 3 syntax. The Python 3 syntax (using a keyword
argument in the type declaration) is preferred and optimised
at compile time.
"final" extension classes prevent inheritance in Python space.
This feature is available through the new "cython.final"
decorator. In the future, these classes may receive further
optimisations.
"internal" extension classes do not show up in the module
dictionary. This feature is available through the new
"cython.internal" decorator.
Extension type inheritance from builtin types, such as "cdef
class MyUnicode(unicode)", now works without further external
type redeclarations (which are also strongly discouraged now
and continue to issue a warning).
GDB support. http://docs.cython.org/src/userguide/debugging.html
A new build system with support for inline distutils directives,
correct dependency tracking, and parallel compilation.
http://wiki.cython.org/enhancements/distutils_preprocessing
Support for dynamic compilation at runtime via the new
cython.inline function and cython.compile decorator.
http://wiki.cython.org/enhancements/inline
General improvements and bug fixes
In parallel assignments, the right side was evaluated in reverse
order in 0.13. This could result in errors if it had side
effects (e.g. function calls).
In some cases, methods of builtin types would raise a SystemError
instead of an AttributeError when called on None.
Constant tuples are now cached over the lifetime of an extension
module, just like CPython does. Constant argument tuples of
Python function calls are also cached.
Closures have tightened to include exactly the names used in
the inner functions and classes. Previously, they held the
complete locals of the defining function.
"nogil" blocks are supported when compiling pure Python code
by writing "with cython.nogil".
The builtin "next()" function in Python 2.6 and later is now
implemented internally and therefore available in all Python
versions. This makes it the preferred and portable way of
manually advancing an iterator.
In addition to the previously supported inlined generator
expressions in 0.13, "sorted(genexpr)" can now be used as well.
Typing issues were fixed in "sum(genexpr)" that could lead to
invalid C code being generated. Other known issues with inlined
generator expressions were also fixed that make upgrading to
0.14 a strong recommendation for code that uses them. Note that
general generators and generator expressions continue to be
not supported.
Iterating over arbitrary pointer types is now supported, as is
an optimized version of the in operator, e.g. x in ptr[a:b].
Inplace arithmetic operators now respect the cdivision directive
and are supported for complex types.
Incompatible changes
Typing a variable as type "complex" previously gave it the
Python object type. It now uses the appropriate C/C++ double
complex type. A side-effect is that assignments and typed
function parameters now accept anything that Python can coerce
to a complex, including integers and floats, and not only
complex instances.
Large integer literals pass through the compiler in a safer
way. To prevent truncation in C code, non 32-bit literals are
turned into Python objects if not used in a C context. This
context can either be given by a clear C literal suffix such
as "UL" or "LL" (or "L" in Python 3 code), or it can be an
assignment to a typed variable or a typed function argument,
in which case it is up to the user to take care of a sufficiently
large value space of the target.
Python functions are declared in the order they appear in the
file, rather than all being created at module creation time.
This is consistent with Python and needed to support, for
example, conditional or repeated declarations of functions. In
the face of circular imports this may cause code to break, so
a new --disable-function-redefinition flag was added to revert
to the old behavior. This flag will be removed in a future
release, so should only be used as a stopgap until old code
can be fixed.
Remove devel/py-ctypes (only needed by and supporting python24).
Remove PYTHON_VERSIONS_ACCEPTED and PYTHON_VERSIONS_INCOMPATIBLE
lines that just mirror defaults now.
Miscellaneous cleanup while editing all these files.
