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.
wiz
drochner