1================ 2Cython Changelog 3================ 4 50.20.2 (2014-06-16) 6=================== 7 8Features added 9-------------- 10 11* Some optimisations for set/frozenset instantiation. 12 13* Support for C++ unordered_set and unordered_map. 14 15Bugs fixed 16---------- 17 18* Access to attributes of optimised builtin methods (e.g. 19 ``[].append.__name__``) could fail to compile. 20 21* Memory leak when extension subtypes add a memory view as attribute 22 to those of the parent type without having Python object attributes 23 or a user provided dealloc method. 24 25* Compiler crash on readonly properties in "binding" mode. 26 27* Auto-encoding with ``c_string_encoding=ascii`` failed in Py3.3. 28 29* Crash when subtyping freelist enabled Cython extension types with 30 Python classes that use ``__slots__``. 31 32* Freelist usage is restricted to CPython to avoid problems with other 33 Python implementations. 34 35* Memory leak in memory views when copying overlapping, contiguous slices. 36 37* Format checking when requesting non-contiguous buffers from 38 ``cython.array`` objects was disabled in Py3. 39 40* C++ destructor calls in extension types could fail to compile in clang. 41 42* Buffer format validation failed for sequences of strings in structs. 43 44* Docstrings on extension type attributes in .pxd files were rejected. 45 46 470.20.1 (2014-02-11) 48=================== 49 50Bugs fixed 51---------- 52 53* Build error under recent MacOS-X versions where ``isspace()`` could not be 54 resolved by clang. 55 56* List/Tuple literals multiplied by more than one factor were only multiplied 57 by the last factor instead of all. 58 59* Lookups of special methods (specifically for context managers) could fail 60 in Python <= 2.6/3.1. 61 62* Local variables were erroneously appended to the signature introspection 63 of Cython implemented functions with keyword-only arguments under Python 3. 64 65* In-place assignments to variables with inferred Python builtin/extension 66 types could fail with type errors if the result value type was incompatible 67 with the type of the previous value. 68 69* The C code generation order of cdef classes, closures, helper code, 70 etc. was not deterministic, thus leading to high code churn. 71 72* Type inference could fail to deduce C enum types. 73 74* Type inference could deduce unsafe or inefficient types from integer 75 assignments within a mix of inferred Python variables and integer 76 variables. 77 78 79 800.20 (2014-01-18) 81================= 82 83Features added 84-------------- 85 86* Support for CPython 3.4. 87 88* Support for calling C++ template functions. 89 90* ``yield`` is supported in ``finally`` clauses. 91 92* The C code generated for finally blocks is duplicated for each exit 93 case to allow for better optimisations by the C compiler. 94 95* Cython tries to undo the Python optimisationism of assigning a bound 96 method to a local variable when it can generate better code for the 97 direct call. 98 99* Constant Python float values are cached. 100 101* String equality comparisons can use faster type specific code in 102 more cases than before. 103 104* String/Unicode formatting using the '%' operator uses a faster 105 C-API call. 106 107* ``bytearray`` has become a known type and supports coercion from and 108 to C strings. Indexing, slicing and decoding is optimised. Note that 109 this may have an impact on existing code due to type inference. 110 111* Using ``cdef basestring stringvar`` and function arguments typed as 112 ``basestring`` is now meaningful and allows assigning exactly 113 ``str`` and ``unicode`` objects, but no subtypes of these types. 114 115* Support for the ``__debug__`` builtin. 116 117* Assertions in Cython compiled modules are disabled if the running 118 Python interpreter was started with the "-O" option. 119 120* Some types that Cython provides internally, such as functions and 121 generators, are now shared across modules if more than one Cython 122 implemented module is imported. 123 124* The type inference algorithm works more fine granular by taking the 125 results of the control flow analysis into account. 126 127* A new script in ``bin/cythonize`` provides a command line frontend 128 to the cythonize() compilation function (including distutils build). 129 130* The new extension type decorator ``@cython.no_gc_clear`` prevents 131 objects from being cleared during cyclic garbage collection, thus 132 making sure that object attributes are kept alive until deallocation. 133 134* During cyclic garbage collection, attributes of extension types that 135 cannot create reference cycles due to their type (e.g. strings) are 136 no longer considered for traversal or clearing. This can reduce the 137 processing overhead when searching for or cleaning up reference cycles. 138 139* Package compilation (i.e. ``__init__.py`` files) now works, starting 140 with Python 3.3. 141 142* The cython-mode.el script for Emacs was updated. Patch by Ivan Andrus. 143 144* An option common_utility_include_dir was added to cythonize() to save 145 oft-used utility code once in a separate directory rather than as 146 part of each generated file. 147 148* ``unraisable_tracebacks`` directive added to control printing of 149 tracebacks of unraisable exceptions. 150 151Bugs fixed 152---------- 153 154* Abstract Python classes that subtyped a Cython extension type 155 failed to raise an exception on instantiation, and thus ended 156 up being instantiated. 157 158* ``set.add(a_tuple)`` and ``set.discard(a_tuple)`` failed with a 159 TypeError in Py2.4. 160 161* The PEP 3155 ``__qualname__`` was incorrect for nested classes and 162 inner classes/functions declared as ``global``. 163 164* Several corner cases in the try-finally statement were fixed. 165 166* The metaclass of a Python class was not inherited from its parent 167 class(es). It is now extracted from the list of base classes if not 168 provided explicitly using the Py3 ``metaclass`` keyword argument. 169 In Py2 compilation mode, a ``__metaclass__`` entry in the class 170 dict will still take precedence if not using Py3 metaclass syntax, 171 but only *after* creating the class dict (which may have been done 172 by a metaclass of a base class, see PEP 3115). It is generally 173 recommended to use the explicit Py3 syntax to define metaclasses 174 for Python types at compile time. 175 176* The automatic C switch statement generation behaves more safely for 177 heterogeneous value types (e.g. mixing enum and char), allowing for 178 a slightly wider application and reducing corner cases. It now always 179 generates a 'default' clause to avoid C compiler warnings about 180 unmatched enum values. 181 182* Fixed a bug where class hierarchies declared out-of-order could result 183 in broken generated code. 184 185* Fixed a bug which prevented overriding const methods of C++ classes. 186 187* Fixed a crash when converting Python objects to C++ strings fails. 188 189Other changes 190------------- 191 192* In Py3 compilation mode, Python2-style metaclasses declared by a 193 ``__metaclass__`` class dict entry are ignored. 194 195* In Py3.4+, the Cython generator type uses ``tp_finalize()`` for safer 196 cleanup instead of ``tp_del()``. 197 198 1990.19.2 (2013-10-13) 200=================== 201 202Features added 203-------------- 204 205Bugs fixed 206---------- 207 208* Some standard declarations were fixed or updated, including the previously 209 incorrect declaration of ``PyBuffer_FillInfo()`` and some missing bits in 210 ``libc.math``. 211 212* Heap allocated subtypes of ``type`` used the wrong base type struct at the 213 C level. 214 215* Calling the unbound method dict.keys/value/items() in dict subtypes could 216 call the bound object method instead of the unbound supertype method. 217 218* "yield" wasn't supported in "return" value expressions. 219 220* Using the "bint" type in memory views lead to unexpected results. 221 It is now an error. 222 223* Assignments to global/closure variables could catch them in an illegal state 224 while deallocating the old value. 225 226Other changes 227------------- 228 229 2300.19.1 (2013-05-11) 231=================== 232 233Features added 234-------------- 235 236* Completely empty C-API structs for extension type slots (protocols like 237 number/mapping/sequence) are no longer generated into the C code. 238 239* Docstrings that directly follow a public/readonly attribute declaration 240 in a cdef class will be used as docstring of the auto-generated property. 241 This fixes ticket 206. 242 243* The automatic signature documentation tries to preserve more semantics 244 of default arguments and argument types. Specifically, ``bint`` arguments 245 now appear as type ``bool``. 246 247* A warning is emitted when negative literal indices are found inside of 248 a code section that disables ``wraparound`` handling. This helps with 249 fixing invalid code that might fail in the face of future compiler 250 optimisations. 251 252* Constant folding for boolean expressions (and/or) was improved. 253 254* Added a build_dir option to cythonize() which allows one to place 255 the generated .c files outside the source tree. 256 257Bugs fixed 258---------- 259 260* ``isinstance(X, type)`` failed to get optimised into a call to 261 ``PyType_Check()``, as done for other builtin types. 262 263* A spurious "from datetime cimport *" was removed from the "cpython" 264 declaration package. This means that the "datetime" declarations 265 (added in 0.19) are no longer available directly from the "cpython" 266 namespace, but only from "cpython.datetime". This is the correct 267 way of doing it because the declarations refer to a standard library 268 module, not the core CPython C-API itself. 269 270* The C code for extension types is now generated in topological order 271 instead of source code order to avoid C compiler errors about missing 272 declarations for subtypes that are defined before their parent. 273 274* The ``memoryview`` type name no longer shows up in the module dict of 275 modules that use memory views. This fixes trac ticket 775. 276 277* Regression in 0.19 that rejected valid C expressions from being used 278 in C array size declarations. 279 280* In C++ mode, the C99-only keyword ``restrict`` could accidentally be 281 seen by the GNU C++ compiler. It is now specially handled for both 282 GCC and MSVC. 283 284* Testing large (> int) C integer values for their truth value could fail 285 due to integer wrap-around. 286 287Other changes 288------------- 289 290 2910.19 (2013-04-19) 292================= 293 294Features added 295-------------- 296 297* New directives ``c_string_type`` and ``c_string_encoding`` to more easily 298 and automatically convert between C strings and the different Python string 299 types. 300 301* The extension type flag ``Py_TPFLAGS_HAVE_VERSION_TAG`` is enabled by default 302 on extension types and can be disabled using the ``type_version_tag`` compiler 303 directive. 304 305* EXPERIMENTAL support for simple Cython code level line tracing. Enabled by 306 the "linetrace" compiler directive. 307 308* Cython implemented functions make their argument and return type annotations 309 available through the ``__annotations__`` attribute (PEP 3107). 310 311* Access to non-cdef module globals and Python object attributes is faster. 312 313* ``Py_UNICODE*`` coerces from and to Python unicode strings. This is 314 helpful when talking to Windows APIs, which use compatible wchar_t 315 arrays for strings. Note that the ``Py_UNICODE`` type is otherwise 316 deprecated as of CPython 3.3. 317 318* ``isinstance(obj, basestring)`` is optimised. In Python 3 it only tests 319 for instances of ``str`` (i.e. Py2 ``unicode``). 320 321* The ``basestring`` builtin is mapped to ``str`` (i.e. Py2 ``unicode``) when 322 compiling the generated C code under Python 3. 323 324* Closures use freelists, which can speed up their creation quite substantially. 325 This is also visible for short running generator expressions, for example. 326 327* A new class decorator ``@cython.freelist(N)`` creates a static freelist of N 328 instances for an extension type, thus avoiding the costly allocation step if 329 possible. This can speed up object instantiation by 20-30% in suitable 330 scenarios. Note that freelists are currently only supported for base types, 331 not for types that inherit from others. 332 333* Fast extension type instantiation using the ``Type.__new__(Type)`` idiom has 334 gained support for passing arguments. It is also a bit faster for types defined 335 inside of the module. 336 337* The Python2-only dict methods ``.iter*()`` and ``.view*()`` (requires Python 2.7) 338 are automatically mapped to the equivalent keys/values/items methods in Python 3 339 for typed dictionaries. 340 341* Slicing unicode strings, lists and tuples is faster. 342 343* list.append() is faster on average. 344 345* ``raise Exception() from None`` suppresses the exception context in Py3.3. 346 347* Py3 compatible ``exec(tuple)`` syntax is supported in Py2 code. 348 349* Keyword arguments are supported for cdef functions. 350 351* External C++ classes can be declared nogil. Patch by John Stumpo. This fixes 352 trac ticket 805. 353 354Bugs fixed 355---------- 356 357* 2-value slicing of unknown objects passes the correct slice when the ``getitem`` 358 protocol is used instead of the ``getslice`` protocol (especially in Python 3), 359 i.e. ``None`` values for missing bounds instead of ``[0,maxsize]``. It is also 360 a bit faster in some cases, e.g. for constant bounds. This fixes trac ticket 636. 361 362* Cascaded assignments of None values to extension type variables failed with 363 a ``TypeError`` at runtime. 364 365* The ``__defaults__`` attribute was not writable for Cython implemented 366 functions. 367 368* Default values of keyword-only arguments showed up in ``__defaults__`` instead 369 of ``__kwdefaults__`` (which was not implemented). Both are available for 370 Cython implemented functions now, as specified in Python 3.x. 371 372* ``yield`` works inside of ``with gil`` sections. It previously lead to a crash. 373 This fixes trac ticket 803. 374 375* Static methods without explicitly named positional arguments (e.g. having only 376 ``*args``) crashed when being called. This fixes trac ticket 804. 377 378* ``dir()`` without arguments previously returned an unsorted list, which now 379 gets sorted as expected. 380 381* ``dict.items()``, ``dict.keys()`` and ``dict.values()`` no longer return lists 382 in Python 3. 383 384* Exiting from an ``except-as`` clause now deletes the exception in Python 3 mode. 385 386* The declarations of ``frexp()`` and ``ldexp()`` in ``math.pxd`` were incorrect. 387 388Other changes 389------------- 390 391 3920.18 (2013-01-28) 393================= 394 395Features added 396-------------- 397 398* Named Unicode escapes ("\N{...}") are supported. 399 400* Python functions/classes provide the special attribute "__qualname__" 401 as defined by PEP 3155. 402 403* Added a directive ``overflowcheck`` which raises an OverflowException when 404 arithmetic with C ints overflow. This has a modest performance penalty, but 405 is much faster than using Python ints. 406 407* Calls to nested Python functions are resolved at compile time. 408 409* Type inference works across nested functions. 410 411* ``py_bytes_string.decode(...)`` is optimised. 412 413* C ``const`` declarations are supported in the language. 414 415Bugs fixed 416---------- 417 418* Automatic C++ exception mapping didn't work in nogil functions (only in 419 "with nogil" blocks). 420 421Other changes 422------------- 423 424 4250.17.4 (2013-01-03) 426=================== 427 428Bugs fixed 429---------- 430 431* Garbage collection triggered during deallocation of container classes could lead to a double-deallocation. 432 433 4340.17.3 (2012-12-14) 435=================== 436 437Features added 438-------------- 439 440Bugs fixed 441---------- 442 443* 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. 444 445* Weak-reference support in extension types (with a ``cdef __weakref__`` attribute) generated incorrect deallocation code. 446 447* 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. 448 449* Negative C integer constants lost their longness suffix in the generated C code. 450 451Other changes 452------------- 453 454 4550.17.2 (2012-11-20) 456=================== 457 458Features added 459-------------- 460 461* ``cythonize()`` gained a best effort compile mode that can be used to simply ignore .py files that fail to compile. 462 463Bugs fixed 464---------- 465 466* 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. 467 468* C-to-Python type coercions during cascaded comparisons could generate invalid C code, specifically when using the 'in' operator. 469 470* "obj[1,]" passed a single integer into the item getter instead of a tuple. 471 472* Cyclic imports at module init time did not work in Py3. 473 474* The names of C++ destructors for template classes were built incorrectly. 475 476* In pure mode, type casts in Cython syntax and the C ampersand operator are now rejected. Use the pure mode replacements instead. 477 478* In pure mode, C type names and the sizeof() function are no longer recognised as such and can be used as normal Python names. 479 480* The extended C level support for the CPython array type was declared too late to be used by user defined classes. 481 482* C++ class nesting was broken. 483 484* Better checking for required nullary constructors for stack-allocated C++ instances. 485 486* Remove module docstring in no-docstring mode. 487 488* Fix specialization for varargs function signatures. 489 490* Fix several compiler crashes. 491 492Other changes 493------------- 494 495* An experimental distutils script for compiling the CPython standard library was added as Tools/cystdlib.py. 496 497 4980.17.1 (2012-09-26) 499=================== 500 501Features added 502-------------- 503 504Bugs fixed 505---------- 506 507* A reference leak was fixed in the new dict iteration code when the loop target was not a plain variable but an unpacked tuple. 508 509* Memory views did not handle the special case of a NULL buffer strides value, as allowed by PEP3118. 510 511Other changes 512------------- 513 514 5150.17 (2012-09-01) 516================= 517 518Features added 519-------------- 520 521* Alpha quality support for compiling and running Cython generated extension modules in PyPy (through cpyext). Note that this requires at least PyPy 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. 522 523* "yield from" is supported (PEP 380) and a couple of minor problems with generators were fixed. 524 525* C++ STL container classes automatically coerce from and to the equivalent Python container types on typed assignments and casts. Note that the data in the containers is copied during this conversion. 526 527* 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)). 528 529* cdef classes can now have C++ class members (provided a zero-argument constructor exists) 530 531* 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. 532 533* Fast dict iteration is now enabled optimistically also for untyped variables when the common iteration methods are used. 534 535* The unicode string processing code was adapted for the upcoming CPython 3.3 (PEP 393, new Unicode buffer layout). 536 537* Buffer arguments and memory view arguments in Python functions can be declared "not None" to raise a TypeError on None input. 538 539* c(p)def functions in pure mode can specify their return type with "@cython.returns()". 540 541* Automatic dispatch for fused functions with memoryview arguments 542 543* Support newaxis indexing for memoryviews 544 545* Support decorators for fused functions 546 547Bugs fixed 548---------- 549 550* 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). 551 552* 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. 553 554* 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. 555 556* locals() properly ignores names that do not have Python compatible types (including automatically inferred types). 557 558* Some garbage collection issues of memory views were fixed. 559 560* numpy.pxd compiles in Python 3 mode. 561 562* Several C compiler warnings were fixed. 563 564* Several bugs related to memoryviews and fused types were fixed. 565 566* Several bug-fixes and improvements related to cythonize(), including ccache-style caching. 567 568Other changes 569------------- 570 571* libc.string provides a convenience declaration for const uchar in addition to const char. 572 573* User declared char* types are now recognised as such and auto-coerce to and from Python bytes strings. 574 575* callable() and next() compile to more efficient C code. 576 577* list.append() is faster on average. 578 579* Modules generated by @cython.inline() are written into the directory pointed to by the environment variable CYTHON_CACHE_DIR if set. 580 581 5820.16 (2012-04-21) 583================= 584 585Features added 586-------------- 587 588* Enhancements to Cython's function type (support for weak references, default arguments, code objects, dynamic attributes, classmethods, staticmethods, and more) 589 590* Fused Types - Template-like support for functions and methods CEP 522 (docs) 591 592* Typed views on memory - Support for efficient direct and indirect buffers (indexing, slicing, transposing, ...) CEP 517 (docs) 593 594* super() without arguments 595 596* Final cdef methods (which translate into direct calls on known instances) 597 598Bugs fixed 599---------- 600 601* fix alignment handling for record types in buffer support 602 603Other changes 604------------- 605 606* support default arguments for closures 607 608* search sys.path for pxd files 609 610* support C++ template casting 611 612* faster traceback building and faster generator termination 613 614* support inplace operators on indexed buffers 615 616* allow nested prange sections 617 618 6190.15.1 (2011-09-19) 620=================== 621 622Features added 623-------------- 624 625Bugs fixed 626---------- 627 628Other changes 629------------- 630 631 6320.15 (2011-08-05) 633================= 634 635Features added 636-------------- 637 638* Generators (yield) - Cython has full support for generators, generator expressions and PEP 342 coroutines. 639 640* The nonlocal keyword is supported. 641 642* Re-acquiring the gil: with gil - works as expected within a nogil context. 643 644* OpenMP support: prange. 645 646* Control flow analysis prunes dead code and emits warnings and errors about uninitialised variables. 647 648* Debugger command cy set to assign values of expressions to Cython variables and cy exec counterpart $cy_eval(). 649 650* Exception chaining PEP 3134. 651 652* Relative imports PEP 328. 653 654* Improved pure syntax including cython.cclass, cython.cfunc, and cython.ccall. 655 656* The with statement has its own dedicated and faster C implementation. 657 658* Support for del. 659 660* Boundschecking directives implemented for builtin Python sequence types. 661 662* Several updates and additions to the shipped standard library .pxd files. 663 664* Forward declaration of types is no longer required for circular references. 665 666Bugs fixed 667---------- 668 669Other changes 670------------- 671 672* Uninitialized variables are no longer initialized to None and accessing them has the same semantics as standard Python. 673 674* 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 675 676* 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. 677 678* 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. 679 680 6810.14.1 (2011-02-04) 682=================== 683 684Features added 685-------------- 686 687* The gdb debugging support was extended to include all major Cython features, including closures. 688 689* raise MemoryError() is now safe to use as Cython replaces it with the correct C-API call. 690 691Bugs fixed 692---------- 693 694Other changes 695------------- 696 697* Decorators on special methods of cdef classes now raise a compile time error rather than being ignored. 698 699* 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. 700 701 7020.14 (2010-12-14) 703================= 704 705Features added 706-------------- 707 708* Python classes can now be nested and receive a proper closure at definition time. 709 710* Redefinition is supported for Python functions, even within the same scope. 711 712* Lambda expressions are supported in class bodies and at the module level. 713 714* 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. 715 716* "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. 717 718* "internal" extension classes do not show up in the module dictionary. This feature is available through the new "cython.internal" decorator. 719 720* 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). 721 722* GDB support. http://docs.cython.org/src/userguide/debugging.html 723 724* A new build system with support for inline distutils directives, correct dependency tracking, and parallel compilation. http://wiki.cython.org/enhancements/distutils_preprocessing 725 726* Support for dynamic compilation at runtime via the new cython.inline function and cython.compile decorator. http://wiki.cython.org/enhancements/inline 727 728* "nogil" blocks are supported when compiling pure Python code by writing "with cython.nogil". 729 730* Iterating over arbitrary pointer types is now supported, as is an optimized version of the in operator, e.g. x in ptr[a:b]. 731 732Bugs fixed 733---------- 734 735* 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). 736 737* In some cases, methods of builtin types would raise a SystemError instead of an AttributeError when called on None. 738 739Other changes 740------------- 741 742* 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. 743 744* 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. 745 746* 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. 747 748* 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. 749 750* Inplace arithmetic operators now respect the cdivision directive and are supported for complex types. 751 752* 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. 753 754* 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. 755 756* 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. 757 758 7590.13 (2010-08-25) 760================= 761 762Features added 763-------------- 764 765* Closures are fully supported for Python functions. Cython supports inner functions and lambda expressions. Generators and generator expressions are not supported in this release. 766 767* Proper C++ support. Cython knows about C++ classes, templates and overloaded function signatures, so that Cython code can interact with them in a straight forward way. 768 769* Type inference is enabled by default for safe C types (e.g. double, bint, C++ classes) and known extension types. This reduces the need for explicit type declarations and can improve the performance of untyped code in some cases. There is also a verbose compile mode for testing the impact on user code. 770 771* Cython's for-in-loop can iterate over C arrays and sliced pointers. The type of the loop variable will be inferred automatically in this case. 772 773* The Py_UNICODE integer type for Unicode code points is fully supported, including for-loops and 'in' tests on unicode strings. It coerces from and to single character unicode strings. Note that untyped for-loop variables will automatically be inferred as Py_UNICODE when iterating over a unicode string. In most cases, this will be much more efficient than yielding sliced string objects, but can also have a negative performance impact when the variable is used in a Python context multiple times, so that it needs to coerce to a unicode string object more than once. If this happens, typing the loop variable as unicode or object will help. 774 775* The built-in functions any(), all(), sum(), list(), set() and dict() are inlined as plain for loops when called on generator expressions. Note that generator expressions are not generally supported apart from this feature. Also, tuple(genexpr) is not currently supported - use tuple([listcomp]) instead. 776 777* More shipped standard library declarations. The python_* and stdlib/stdio .pxd files have been deprecated in favor of clib.* and cpython[.*] and may get removed in a future release. 778 779* Pure Python mode no longer disallows non-Python keywords like 'cdef', 'include' or 'cimport'. It also no longer recognises syntax extensions like the for-from loop. 780 781* Parsing has improved for Python 3 syntax in Python code, although not all features are correctly supported. The missing Python 3 features are being worked on for the next release. 782 783* from __future__ import print_function is supported in Python 2.6 and later. Note that there is currently no emulation for earlier Python versions, so code that uses print() with this future import will require at least Python 2.6. 784 785* New compiler directive language_level (valid values: 2 or 3) with corresponding command line options -2 and -3 requests source code compatibility with Python 2.x or Python 3.x respectively. Language level 3 currently enforces unicode literals for unprefixed string literals, enables the print function (requires Python 2.6 or later) and keeps loop variables in list comprehensions from leaking. 786 787* Loop variables in set/dict comprehensions no longer leak into the surrounding scope (following Python 2.7). List comprehensions are unchanged in language level 2. 788 789* print >> stream 790 791Bugs fixed 792---------- 793 794Other changes 795------------- 796 797* The availability of type inference by default means that Cython will also infer the type of pointers on assignments. Previously, code like this:: 798 799 cdef char* s = ... 800 untyped_variable = s 801 802 would convert the char* to a Python bytes string and assign that. This is no longer the case and no coercion will happen in the example above. The correct way of doing this is through an explicit cast or by typing the target variable, i.e. 803 804 :: 805 806 cdef char* s = ... 807 untyped_variable1 = <bytes>s 808 untyped_variable2 = <object>s 809 810 cdef object py_object = s 811 cdef bytes bytes_string = s 812 813* bool is no longer a valid type name by default. The problem is that it's not clear whether bool should refer to the Python type or the C++ type, and expecting one and finding the other has already led to several hard-to-find bugs. Both types are available for importing: you can use from cpython cimport bool for the Python bool type, and from libcpp cimport bool for the C++ type. bool is still a valid object by default, so one can still write bool(x). 814 815* ``__getsegcount__`` is now correctly typed to take a ``Py_size_t*`` rather than an ``int*``. 816 817 8180.12.1 (2010-02-02) 819=================== 820 821Features added 822-------------- 823 824* Type inference improvements. 825 826 * There have been several bug fixes and improvements to the type inferencer. 827 828 * Notably, there is now a "safe" mode enabled by setting the infer_types directive to None. (The None here refers to the "default" mode, which will be the default in 0.13.) This safe mode limits inference to Python object types and C doubles, which should speed up execution without affecting any semantics such as integer overflow behavior like infer_types=True might. There is also an infer_types.verbose option which allows one to see what types are inferred. 829 830* The boundscheck directive works for lists and tuples as well as buffers. 831 832* len(s) and s.decode("encoding") are efficiently supported for char* s. 833 834* Cython's INLINE macro has been renamed to CYTHON_INLINE to reduce conflict and has better support for the MSVC compiler on Windows. It is no longer clobbered if externally defined. 835 836* Revision history is now omitted from the source package, resulting in a 85% size reduction. Running make repo will download the history and turn the directory into a complete Mercurial working repository. 837 838* Cython modules don't need to be recompiled when the size of an external type grows. (A warning, rather than an error, is produced.) This should be helpful for binary distributions relying on NumPy. 839 840Bugs fixed 841---------- 842 843* Several other bugs and minor improvements have been made. This release should be fully backwards compatible with 0.12. 844 845Other changes 846------------- 847 848 8490.12 (2009-11-23) 850================= 851 852Features added 853-------------- 854 855* Type inference with the infer_types directive 856 857* Seamless C++ complex support 858 859* Fast extension type instantiation using the normal Python meme obj = MyType.__new__(MyType) 860 861* Improved support for Py3.1 862 863* Cython now runs under Python 3.x using the 2to3 tool 864 865* unittest support for doctests in Cython modules 866 867* Optimised handling of C strings (char*): for c in cstring[2:50] and cstring.decode() 868 869* Looping over c pointers: for i in intptr[:50]. 870 871* pyximport improvements 872 873* cython_freeze improvements 874 875Bugs fixed 876---------- 877 878* Many bug fixes 879 880Other changes 881------------- 882 883* Many other optimisation, e.g. enumerate() loops, parallel swap assignments (a,b = b,a), and unicode.encode() 884 885* More complete numpy.pxd 886 887 8880.11.2 (2009-05-20) 889=================== 890 891Features added 892-------------- 893 894* There's now native complex floating point support! C99 complex will be used if complex.h is included, otherwise explicit complex arithmetic working on all C compilers is used. [Robert Bradshaw] 895 896 :: 897 898 cdef double complex a = 1 + 0.3j 899 cdef np.ndarray[np.complex128_t, ndim=2] arr = \ 900 np.zeros(10, np.complex128) 901 902* Cython can now generate a main()-method for embedding of the Python interpreter into an executable (see #289) [Robert Bradshaw] 903 904* @wraparound directive (another way to disable arr[idx] for negative idx) [Dag Sverre Seljebotn] 905 906* Correct support for NumPy record dtypes with different alignments, and "cdef packed struct" support [Dag Sverre Seljebotn] 907 908* @callspec directive, allowing custom calling convention macros [Lisandro Dalcin] 909 910Bugs fixed 911---------- 912 913Other changes 914------------- 915 916* Bug fixes and smaller improvements. For the full list, see [1]. 917