# What’s new in PyObjC

An overview of the relevant changes in new, and older, releases.

## Version 6.2.2

- #311: Build for the Metal bindings failed on macOS 10.14

- #309: Fix incompatibility with macOS 11 in framework loader

- Another attempt at giving a nice error message when trying to install on platforms other than macOS.

- The classifiers now correctly identify supported Python versions

## Version 6.2.1

- Issue #299: Ensure package ‘pyobjc’ won’t try to build the PubSub bindings on macOS 10.15

  Reported by Thomas Buchberger

- Minor tweaks to build and pass tests on macOS 10.14 with the latest Xcode that can be installed on that version of macOS.

- Issue #300: Fix SystemError in block edge case

  PyObjC raised a SystemError when converting a callable into an ObjC block when the callable is a bound method without positional arguments.

- Issue #275: Fix crash on catalina caused by writing to read-only memory.

  > Patch by Dan Villiom Podlaski Christiansen

- PR #302: Make sure the SDK detection works when the version is not in the SDK name

  Patch by Joshua Root

- There were no SDK updates in Xcode 11.5 and Xcode 11.6 (beta)

## Version 6.2

- The project has moved from Bitbucket to Github

- Remove most remnants of Python 2 support

- Clean up code quality issues found using flake8

- Add pre-commit hook to run black on all Python code.

- #290: Fix protocol conformance testing when explicitly implementing a protocol

  Before this bugfix a class explicitly conforming to a protocol could not implement any method that wasn’t declared in the protocol, the bridge would erroneously raise an exception when checking the additional method.

  Issue reported by Georg Seifert.

- #289: Fix Python 3 issues in `PyObjCTools.Conversion`

  Reported by vinolin asokan.

- `PyObjCTools.Conversio.propertyListFromPythonCollection` didn’t

    recursively convert members of lists and tuples.

- `PyObjCTools.Conversio.propertyListFromPythonCollection` and `PyObjCTools.Conversio.pythonCollectionFromPropertyList` now support sets.

- Update metadata for Xcode 11.4 (beta 2)

- Added bindings for framework `AutomaticAssessmentConfiguration.framework` introduced in macOS 10.15.4

- #298: In some cases the compiler uses the type encoding “^{NSObject=#}” instead of “@”.

  Reported by Georg Seifert.

- #264: Added bindings for the Metal framework (new in macOS 10.11)

- Most framework bindings now use the limited ABI for the included C extensions, reducing the number of wheels that are needed. The exception are the bindings for Cocoa, Quartz and libdispatch, those use functionality not available in the limited ABI.

  The bridge itself (pyobjc-core) still uses the full CPython API.

  The CoreAudio bindings also don’t use the limited ABI for now, those need more work to work with that ABI.

## Version 6.1

- Updated for the macOS 10.15.1 SDK (Xcode 11.2)

- Fix reference counting in -[OC_PythonData length], which resulted in use-after-free.

- #281: Fix problems found in pyobjc-core by the clang static analyser

## Version 6.0.1

- #277: Remove debug print accidently left in production

- #278: Surpress “-Wunguarded-availability” warnings in the extension AppKit._inlines

## Version 6.0

- Removed Python 2 support from the C extension in pyobjc-core

- Reformatted code in pyobjc-core:

  - Use “black” for Python code

  - Use “clang-format” for Objective-C code

    As a side-effect of this all usage of “NS_DURING” and “PyObjC_DURING” has been replaced by the expansion of those macros, mostly because “clang-format” doesn’t understand these kinds of blocks.

    Replacing “PyObjC_DURING” by its expansion also reduces the knowledge needed to understand what’s going on w.r.t. the Python GIL.

    The macro “PyObjC_DURING”, and its siblings, have been removed as well.

- Updated bindings for macOS 10.15 (Xcode 11.0)

- The userspace driver frameworks introduced in macOS 10.15 (DriverKit and related frameworks) will not be exposed through PyObjC. Please let me know if you have a good use case for using these frameworks with Python.

- Add new framework wrappers for all other new frameworks in macOS 10.15:

  - AuthenticationServices

  - CoreHaptics

  - CoreMotion

  - DeviceCheck

  - ExecutionPolicy

  - FileProvider

  - FileProviderUI

  - LinkPresentation

  - OSLog

  - PencilKit

  - PushKit

  - QuickLookThumbnailing

  - Speech

  - SoundAnalysis

  - SystemExtensions

- Add new framework wrappers for a number of older frameworks:

  - MetalKit (new in macOS 10.11)

- Issue #271: Fix crash when creating NSData objects on macOS 10.15

## Version 5.3

- PR 21: Switch xcodebuild invocation to xcrun for sdk path

  Patch by Clément Bouvier

- #271: Fix crash when creating NSData objects on macOS 10.15

- Fix compile error on macOS 10.15

## Version 5.2

- Updated metadata for Xcode 10.2

- #252: `objc.registerStructAlias` no longer emits a deprecation warning because it is still used by the framework wrappers.

  The function is still deprecated though, the deprecation will reappear once the metadata has been updatd.

- #75: The core bridge now uses `PyDict_GetItemWithError()`, which may result in exceptions being raised that were previously swallowed.

- #247: Partially switch to the new buffer API instead of the older Python 2 buffer API.

  The new implementation is more correct, but may keep Python objects alive longer than the previous implementation, and also affects buffer related functionality of Python objects. In particular, calling `[someData bytes]` on a Python object keeps the `Py_buffer` alive until the next flush of the autoreleasepool.

- #257: Fix incorrect metadata for the callback argument to `-[AVCaptureStillImageOutput captureStillImageAsynchronouslyFromConnection:completionHandler:]`.

#258: Add bindings to the “PrintCore” APIs from the ApplicationServices framework.

- Python 2: UserDict.UserDict instances are now bridged to instances of a subclass of NSDictionary.

## Version 5.1.2

- #254: Fix compile error on macOS 10.9 or earlier

- #255: Calling completion handler failed due to incomplete runtime info

  PyObjC’s metadata system didn’t automaticly set the call signature for blocks passed into a method implemented in Python. This causes problems when the ObjC or Swift block does not have signature information in the ObjC/blocks runtime.

- Use MAP_JIT when allocating memory for the executable stubs for Python methods.

  With the “restricted” runtime you’ll have to add the “com.apple.security.cs.allow-jit” entitlement to use this flag, in earlier versions you’d have to use a different entitlement: “com.apple.security.cs.allow-unsigned-executable-memory”.

  The MAP_JIT flag is only used on macOS 10.14 or later.

- Ensure that PyObjC can be built using /usr/bin/python on macOS 10.14

  This failed due the problems with header files in the SDK included with Xcode 10.

## Version 5.1.1

- Update metadata for Xcode 10.1

## Version 5.1

- Xcode 10 “GM” contains one difference from the last beta: the constant MLComputeUnitsCPUAndGPU in the CoreML bindings.

- #222: Add a proxy for C’s “FILE*” type on Python 3. This is not necessary on Python 2 because the default IO stack on Python 2 already uses FILE* internally.

  This proxy type is very minimal and shouldn’t not be used for general I/O.

- Bindings are up-to-date w.r.t. Xcode 10.1 (beta)

- Updated the support code for framework wrappers to be able to emit deprecation warnings on the first import of a deprecated constants (functions and methods will only raise a deprecation warning when called).

  This is just an infrastructure change, the actual framework bindings do not yet contain the information used to emit deprecation warnings.

- Add metadata for deprecation warnings to the “Contacts” framework

- #252: Import ABCs from `collections.abc` instead of `collections` because the latter is deprecated.

- #180, #251: Instances of most builtin value types and sequences (int, float, str, unicode, tuple, list, set, frozenset and dict) can now be written to archives that require secureCoding.

## Version 5.0

Version 5.0 of PyObjC primarily adds support for macOS 10.14 (mojave), and also adds support for a couple of older frameworks that weren’t supported before.

## Version 5.0b2

- Added manual bindings for MTAudioProcessingTapCreate and MTAudioProcessingTapGetStorage in the MediaToolbox bindings.

- Added manual bindings for CMIODeviceProcessAVCCommand and CMIODeviceProcessRS422Command in the CoreMediaIO bindings

- Added bindings for the VideoToolbox framework introduced in macOS 10.8

- Finished bindings for CoreMedia, I noticed during review that the bindings were far from finished.

- Fixed problem with unitialized memory in pyobjc-core

- The CarbonCore bindings included a number of symbols that shouldn’t be exposed

## Version 5.0b1

- Bindings updated for Xcode 10 beta 6.

- Add a custom binding for a number of structure types in CoreAudio:

  - AudioBuffer

  - AudioBufferList

  - AudioChannelDescription

  - AudioChannelLayout

  - AudioValueTranslation

  With this patch using APIs with these types should actually work.

- PR19: Fix deprecation warning in bridgesupport support module

  Patch by: Mickaël Schoentgen

- Creating objc.ObjCPointer instances now results in a Python warning, instead of an unconditional message on stdout.

  Note

  The creation of these objects is a sign that APIs are not wrapped correctly, these objects are created for pointers where the bridge doesn’t know how to handle them properly.

- System bridgesupport XML files (normally not used by PyObjC) can contain constant numbers with value “inf”, PyObjC now knows how to handle those.

- Added bindings for the “Metadata” subframework of the “CoreServices” framework.

- Added bindings for the “CarbonCore” subframework of the “CoreServices” framework.

  Most APIs in this subframework are not available to Python, only those APIs that are not deprecated and seem interesting are exposed.

- The separate framework wrappers DictionaryServices, LaunchServices and SearchKit are deprecated, use the CoreServices bindings instead.

  These framework wrappers still exists, but are effectively aliases for CoreServices with this release. Because of this these bindings can expose more symbols than previously.

- Fix unexpected exception when trying to call getattr on a framework wrapped with a name that isn’t a valid identifier.

- #244: Bad metadata for CGPDFOperatorTableSetCallback

- #247: Fix crash in regression test case

  One specific test in pyobjc-core crashed the interpreter when run separately. Because of this I’ve disabled an optimization that uses alloca instead of PyMem_Malloc to allocate memory for now.

## Version 5.0a0

- Adds support for macOS 10.14 (Mojave)

  This release updates the framework wrappers with support for new APIs in macOS 10.14 and adds bindings for the following new frameworks:

  - AdSupport

  - CoreAudio (new in macOS 10.0)

  - CoreAudioKit (new in macOS 10.4)

  - CoreMedia (new in macOS 10.7)

  - CoreMediaIO (new in macOS 10.7)

  - DiscRecording (new in macOS 10.2)

  - DiscRecordingUI (new in macOS 10.2)

  - DVDPlayback (new in macOS 10.3)

  - MediaToolbox

  - NaturalLanguage

  - Network

  - OSAKit (new in macOS 10.4)

  - UserNotifications

  - VideoSubscriberAccount

- Support for CoreAudio, CoreMedia and MediaToolbox is limited in this release due to missing manual wrappers.

- Added two features that can help with gating code on the version of macos:

  1. The constants “objc.MAC_OS_X_VERSION_CURRENT” can be compared with one of the “objc.MAC_OS_X_VERSION_…” contants.

  2. The function “objc.macos_avaiable(major, minor[, patch])” returns true if the current macOS version is at least the specified version, comparable with “@available” in Swift.

## Version 4.2.2

- Update metadata for Xcode 9.4

- The binary release now includes wheels for both variants for the Python.org installer for python 3.6 and 3.7: 32- and 64-bit for macOS 10.6 or later, and 64-bit only for macOS 10.9 or later.

- Ensure the context manager for `NSAnimationContext` defined in `PyObjCTools.AppCategories` actually works.

- Fix convenience wrappers for `Foundation.NSCache`.

- Fix convenience wrappers for `Foundation.NSHashTable`.

## Version 4.2.1

- Update metadata for Xcode 9.4 beta 2 (no changes)

- Restore autodetection of –with-system-ffi, but ignore this python setting for /usr/bin/python because Apple doesn’t ship libffi headers.

## Version 4.2

- Add bindings to the BusinessChat framework introduced in macOS 10.13.4

- Update metadata for Xcode 9.3

- Issue #233 Fix crash in Security.AuthorizationCopyRights() wrapper

- Issue #234 Fix crash in AuthorizationExecuteWithPrivileges() wrapper

  Reported by Vangelis Koukis

- Ensure doctest can work with modules containing subclasses of NSObject

  Reported by Just van Rossum

- Issue #236 : Importing can sometimes fail in multi-threaded scenarios

  Fix by Max Bélanger

- Undeprecate treating struct wrappers as sequences. Removing this feature would break too much existing code, hence deprecating is not really an option. Furthermore, this would also break some nice idioms.

- Pull request #17: Fix python 3 issues in PyObjCTools.AppHelper and PyObjCTools.Conversion

  Fix by Max Bélanger

## Version 4.1

- Protection agains buffer overflow and negative indexes in `__getitem__` and `__setitem__` for `objc.varlist` instances.

- Fix incorrect metadata for `+[NSEvent addLocalMonitorForEventsMatchingMask:handler:]`

- Fix incorrect and misleading error message in the exception that is raised when return a value from a block that should not return a value.

- Issue #223: Fix hard crash when executing `help(Cocoa)`

  Fetching the help for PyObjC framework wrappers isn’t very useful due to the sheer size of the output (4.5 million lines of output for `help(Cocoa)` at the moment), but shouldn’t cause a hard crash of the interpreter.

  Reported by Dave Fuller

- Issue #218: Explictly cause an ImportError when reloading ``objc._objc``

  Reloading the PyObjC core extension now raises an ImportError because this cannot work and used to raise a rather vague error.

- Updated metadata for Xcode 9.2

- Added missing ``MAC_OS_X_VERSION_*`` constants

- Fix memory error in struct wrappers which resulted in a use-after-free error in the initializer for structs.

- #135: Add bindings for frameworks Security, SecurityFoundation and and SecurityInterface.

  The bindings for the Security framework don’t expose a number of older APIs that were deprecated in macOS 10.7.

- #129: Add bindings to libdispatch.

  These bindings require macOS 10.8 or later, libdispatch was available earlier but macOS 10.8 changed the API in such a way that wrapping became a lot easier.

  Note

  Blocks scheduled using libdispatch are still subject to the Python GIL: just one block implemented in Python can run at any one time.

## Version 4.0.1

- Issue #213: Fix signature for ``-[NSObject forwardInvocation:]``

  Reported by user “pyrocat”

- Updated metadata for Xcode 9.1

- Changes to PyObjCTools.TestSupport to be able to include/exclude tests based on the minor release of macOS.

- Some tweaks to fix test failures when running on OSX 10.5, 10.6, 10.9.

Note

The stacktrace formatting of in `PyObjCTools.Debugging` (from the ExceptionHandling bindings) don’t work for PPC binaries because symbol resolution doesn’t work.

This is a known issue that won’t be fixed.

## Version 4.0

- Issue #204: Metadata for CGPDFDictionaryGetObject was wrong

  Reported by Nickolas Pohilets.

- Updated metadata for Xcode 9 GM.

- Fix #202: Add bindings for `CGPDFDictionaryRef`, `CGPDFScannerRef` `CGPDFStreamRef` and `CGPDFStringRef` to the Quartz bindings (including some minor updates to function metadata)

  Reported by Nickolas Pohilets.

- Issue #205: Add ability to read bytes from `objc.varlist`

  Instances of `objc.varlist` now have a method to return a memoryview that refers to the first section of the list:

      def as_buffer(self, count : int) -> memoryview

  This returns a memoryview the references the underlying memory for the first count elements in the list.

  Reported by Nickolas Pohilets.

- Added bindings for the GameKit framework introduced in macOS 10.8.

- Added bindings for the GameplayKit framework introduced in macOS 10.11.

  Note that these bindings are less useful than they could be because PyObjC currently does not support “vector” types that are used in some APIs.

## Version 4.0b1

- Removed PyObjCTools.TestSupport.filterWarnings, use warnings.catch_warnings instead.

- Building pyobjc-core using “python setup.py develop” will use ‘ccache’ when available.

- Building pyobjc-core will compile the source files from new to old files, to speed up feedback while working on the source code.

- Legacy BridgeSupport files on macOS 10.13 (which aren’t used by default by PyObjC) can contain junk data in typestring data. Cleanup that data before using it.

- Deal with loading bundle variables of a C string type, that used to crash to do an oddity of locating that information.

- Using wrappers for C structs as sequences is deprecated, this feature was introduced a long while ago when the framework wrappers were very incomplete and is no longer usefull.

- Add `objc.options.structs_indexable`. When this option is True (the default) wrappers for C structs behave as before, when the option is False these wrappers can no longer be used as writable tuples, that is all “sequence” methods will raise `TypeError`.

- Add `objc.options.structs_writable`. When this option is True (the default) wrappers for C structs behave as before, when the option is False these wrappers can no longer be modified.

- Add availability macro `MAC_OS_X_VERSION_10_13` to `objc`.

- New framework wrappers:

  - ColorSync (new in macOS 10.13)

  - CoreML (new in macOS 10.13)

  - ExternalAccessory (new in macOS 10.13)

  - CoreSpotlight (new in macOS 10.13)

  - Vision (new in macOS 10.13)

- metadata updates:

  - Accounts

  - AddressBook

  - AppKit

  - ApplicationServices

  - Automator

  - AVKit

  - CalendarStore

  - CFNetwork

  - CloudKit

  - Contacts

  - CoreBluetooth

  - CoreData

  - CoreFoundation

  - CoreGraphics

  - CoreImage

  - CoreLocation

  - CoreServices

  - CoreText

  - CoreVideo

  - CoreWLAN

  - CryptoTokenKit

  - EventKit

  - FinderSync

  - Foundation

  - FSEvents

  - GameController

  - IMServicePlugIn

  - ImageCaptureCore

  - ImageIO

  - Intents

  - IOSurface

  - JavaScriptCore

  - LocalAuthentication

  - MapKit

  - MediaLibrary

  - MediaPlayer

  - ModelIO

  - MultipeerConnectivity

  - NetFS

  - NetworkExtension

  - OpenDirectory

  - Photos

  - PhotosUI

  - QTKit

  - Quartz

  - QuartzCore

  - QuickLook

  - SafariServices

  - SceneKit

  - ScreenSaver

  - Social

  - SpriteKit

  - SystemConfiguration

  - WebKit

## Version 3.3

New features:

- Pull request #15: Fix crash when handling stack blocks

  Patch by Max Bélanger. Fixes a crash when a stackbased block is passed into python.

  Later updated with tests and a different implementation.

- Issue #192: 32/64-bit issue with AppHelper.endSheetMethod

  This helper decorator used the wrong signature string, which happens to work on 32-bit systems but not on 64-bit ones.

- “pip install pyobjc” should now fail with a better error message when installing on a system that isn’t running macOS.

- Updated framework wrappers for the API changes in the SDK shipped with Xcode 8.3.2.

- Added new framework wrapper: “pyobjc-framework-CoreServices”.

  This exposes no new functionality for now, but makes it possible to access the functionality exposed by the “CoreServices” framework by using “import CoreServices”, instead of directly importing the name of the subframework.

- Added new framework wrapper: “pyobjc-framework-iTunesLibrary”

  This is a wrapper for the iTunesLibrary framework located in “/Library/Frameworks”, which is a framework installed by iTunes that can be used to (read-only) access information about an iTunes library.

- Issue #178: Add basic example for the Contacts framework

  The Contacts framwork now contains a very simple example that shows how to fetch contacts from the contact store. Apple’s documentation on the framework contains more comprehensive sample code, which should make it clear how to use the framework.

- Add initial support for deprecation warnings in metadata

  Metadata files can now contain information for deprecation warnings for methods and functions. Users can turn on deprecation warnings using:

      import objc
      objc.deprecation_warnings = objc.MAC_OS_X_VERSION_10_6

  This will emit deprecation warnings for APIs that were deprecated in macOS 10.6 (or earlier).

  Note that this version does have metadata that uses the new functionality, that will be added in a future release.

Bugfixes:

- The OC_Python* Objective-C classes used to expose Python objects to Objective-C don’t support secure coding, added a “supportsSecureCoding” implementation to make this explicit.

- Issue #182: The block signature registered in the ObjC runtime datastructures for Python blocks was wrong, which confuses Objective-C code that looks at the runtime data.

- Fix requirement info in Collaboration setup.py.

  Patch by Alex Chekunkov.

- Issue #189: Invalid invocation of “atos” command on recent macOS versions

  The Objective-C exception logging code in pyobjc-framework-ExceptionHandling calls out to the “atos” command to get readable stack traces, that invocation caused problems on recent macOS versions.

## Version 3.2.2

Bugfixes:

- Issue #162: Fix conversion of unicode python string to Objective-C “UniChar” array, it used to do the wrong thing when converting characters outside of the BMP.

  Fix by Ted Morin and Benoit Pierre.

## Version 3.2.1

Updates:

- Small change to the shared setup.py code for framework wrappers to allow building wheels for wrappers without a C exention on any system.

  This was mostly done to make it easier to provide wheels in future releases.

Bugfixes:

- Avoid build error with Python 2.7 when using the OSX 10.12 SDK, triggered when Python was build using MacPython support.

- Compatibility definitions for MAC_OS_X_VERSION_10_10, MAC_OS_X_VERSION_10_11 and MAC_OS_X_VERSION_10_12 were wrong, adjusted these.

- Fix obscure crash in test suite of pyobjc-core: the definition of a class that claims to conform to a protocol but didn’t actually conform could result in having a partial class definition in the Objective-C runtime.

- Updated implementation for `NSMutableArray.extend`. This both avoids an error with the list interface tests in Python 3.6, and avoids unnecessary memory usage with large arguments.

## Version 3.2

Backward compatibility note: Due to a change in the way the default method signature is calculated PyObjC is now more strict in enforcing the Python<->Objective-C mapping for selectors and a number of code patterns that were allowed before are no longer allowed, in particular the following method definitions raise `objc.BadPrototypeError`:

    class MyObject (NSObject):
       def mymethod(self, a, b): ...
       def method_arg_(self, a, b, c): ...

If these methods are only used from Python and are never used from Objective-C the error can be avoided by decorating these methods with `objc.python_method`:

    class MyObject (NSObject):
       @objc.python_method
       def mymethod(self, a, b): ...

This cannnot be used for methods used from Objective-C, for those you will have to rename the method or you will have to provide an appropriate selector explictly.

- Fix crash when using some APIs in the LaunchServices framework.

- Issue #100:Building with the Command Line Tools for Xcode installed caused build errors on OSX 10.10

- Python 3.6 made a change to the bytecode format that affected the way PyObjC calculates the default method signature for Python methods.

  Earlier versions of PyObjC will therefore not work properly with Python 3.6.

- Update metadata for macOS 10.12.1

  Note: Building PyObjC on macOS 10.12 requires Xcode 8.1 (or a later version)

- Added bindings for the SafariServices and Intents frameworks, both introducted in macOS 10.12.

- Added bindings for the MediaPlayer framework, introducted in macOS 10.12.1.

- Add bindings for the ModelIO framework, introduced in OSX 10.11.

- Issue #153: Add missing metadata file to ApplicationServices bindings

- Issue #157: Bad reference to “_metadata” in ApplicationServices bindings

- ApplicationServices framework didn’t do “from … import *” as was intended.

- Don’t force the installation of py2app.

- Fix build failure using the OSX 10.10 SDK.

- Issue #21: Tweak build procedure for PyObjC to avoid building pyobjc-core multiple times when using `pip install pyobjc`.

- Issue #123: Use Twisted’s cfreactor module in the examples using Twisted.

- Issue #148: Fix build issue for the MapKit bindings on a case sensitive filesystem.

- Added bindings for the IOSurface framework (pyobjc-framework-IOSurface)

- Added bindings for the NetworkExtension framework (pyobjc-framework-NetworkExtension)

- Issue #149: Fix compile problems with Anaconda

- Fix SystemError for accessing a method whose `__metadata__` cannot be calculated, found while researching issue #122.

- Issue #146: Don’t hang when running `python setup.py build` using PyPy.

  Note that PyPy still doesn’t work, this just ensures that the build fails instead of hanging indefinely.

- Issue #143: Fix calculation of default type signature for selectors

  Due to this change it is possible to use decorators like this:

      def decorator(func):
         @functools.wraps(func)
         def wrapper(*args, **kwds):
             return func(*args, **kwds)
         return decorator

  Before this patch PyObjC gave an error due to the signature of `wrapper`, and if `wrapper` was defined with an explicit `self` argument PyObjC would not give an error but would calculate the wrong method signature for wrapped methods.

  An unfortunate side effect of this change is that the argument count of methods must now match the implied argument count of the selector, that is a method with name `someMethod_` must now have exactly two arguments (`self` and the argument implied by the underscore at the end).

  Use `objc.python_method` as a decorator for python methods that don’t use this convention and do no need to be registered with the Objective-C runtime as Objective-C selectors.

- The bridge now considers the default arguments for a function when determining if the Python signature of a function is compatible with the Objective-C signature, that is the following method definition is valid:

      class MyObject (NSObject):
         def someMethod_(self, a, b=2): pass

- The default selector calculated for Python methods with embedded underscores and without a closing underscore has changed, the embedded underscores are not translated to colons because the resulting Objective-C selector would not be valid.

  That is, in earlier versions the default selector for “some_method” would be “some:method”, and from this version on the default for selector for this method is “some_method”.

- (Python 3) Methods and functions with keyword-only arguments that don’t have defaults cause a `objc.BadPrototypeError` exception when proxied to Objective-C because those can never be called from Objective-C without causing an exception.

## Version 3.1.1

- Sigh… A number for sdists were incomplete due to missing MANIFEST.in files.

## Version 3.1

- Fix value of `FLT_MAX` and `FLT_MIN` in framework bindings.

- Fix for the functions in `PyObjCTools.AppHelper`: those functions didn’t work correctly when the calling thread didn’t have a runloop.

  Patch by Max Bélanger.

- Issue #126: Load the LaunchServices definitions through the CoreServices umbrella framework to avoid problems on OSX 10.11.

- Issue #124: Sporadic crash at program shutdown due to a race condition between Python interpreter shutdown and Cocoa cleanup.

  This is mostly a workaround, I don’t have a full solution for this yet and I’m not sure if one is possible.

- Added `objc.PyObjC_BUILD_RELEASE` which contains the version of the SDK that was used to build PyObjC in the same format as the OSX availability macros.

- Added maxTimeout parameter to `PyObjCTools.AppHelper.runConsoleEventLoop` to fix issue #117. The default value is 3 seconds, which means that the console eventloop will stop within 3 seconds of calling `stopEventLoop`.

- Re-enable faster method calls for simple method calls.

- Support OSX 10.10 in PyObjCTools.TestSupport (version comparison was too naive)

- Add bindings for ApplicationServices, currently only the HIServices sub framework is exposed.

- Add bindings for NetFS, introduced in OSX 10.7.

- Add bindings for ImageCaptureCore. Initial patch by Max Bélanger.

- Add bindings for IMServicePlugIn, introduced in OSX 10.7.

- Add bindings for SceneKit, introduced in OSX 10.8.

- Add bindings for CoreBluetooth, MapKit, AVKit, MediaLibrary, MediaAccessibility, GameController (all new in OSX 10.9)

- Add bindings for FinderSync, CloudKit, CryptoTokenKit, MultipeerConnectivity, NotificationCenter (all new in OSX 10.10)

- Add bindings for Contacts, ContactsUI, Photos, PhotosUI (new in OSX 10.11)

- Added function `objc.callbackPointer`.

- Updated bindings for AppKit, CoreData, CoreFoundation, CoreGraphics, CoreLocation, CoreText, CoreVideo, CoreWLAN, EventKit, FSEvents, ImageIO, ImageKit, JavaScriptCore, LaunchServices, OpenDirectory, PDFKit, QuartzComposer, QuartzCore, QuartzFilters, QuickLookUI, ServiceManagement, Social, StoreKit and WebKit with the new APIs introduced in OSX 10.9, 10.10 and 10.11.

- Unchanged framework bindings: Collaboration, DictionaryServices, ExceptionHandling, InputMethodKit, InstallerPlugins, InstantMessage, InterfaceBuilderKit, LatentSemanticMapping, PreferencePanes, PubSub.

  Note

  InterfaceBuilderKit will likely be removed in a future version of PyObjC

- TODO: DiskArbitration, GameController, SpriteKit bindings are incomplete

- Fix hard crash with invalid type strings in metadata.

- Default value for struct wrappers was incorrect for fields that have a type encoding that’s custom to PyObjC.

- Fix a type string validation error that could cause PyObjC to continue processing beyond the end of a type string (which can effectively hang the python interpreter with 100% CPU usage)

- Fix edge-case in NSCoding support that causes PyObjC to use proxy objects of the wrong type in some cases.

- Fix incompatibility with Python 3.6 (where `inspect.getargspec` no longer exists)

- Added (private) function `objc._copyMetadataRegistry`. This function returns a copy of the internal registry that’s used to find additional information about method signatures.

  Note that the data structure returned by this function is subject to change, that the data structure is undocumented and that modifying it does not affect the data used by PyObjC.

## Version 3.0.5

- PyObjC now uses the system libffi when CPython itself was compiled to use that version of libffi.

  Patch by Max Bélanger.

- BridgeSupport code failed when there are unions in the bridgesupport file due to a bug in the code that parses Objective-C encoded types.

  Issue #111

- BridgeSupport code didn’t work properly with Python 3.x

- Add objc.MAC_OS_X_VERSION_10_10 and MAC_OS_X_VERSION_10_9.

- The code that checked for compliance to formal protocols didn’t look at parent classes to determine if a class implements the protocol.

  Issue #107

- Fix build issue for python 3.

## Version 3.0.4

- Fix installation on OSX 10.10 when using “pip install pyobjc”.

  Issues #102, #103.

- Fix crash when `sys.modules` contains an object that is not a string.

  Issue #95.

- Fix crash on OSX 10.8 or later when using a 32-bit build and accessing an instance of “Object” (that is, pre-Nextstep classes).

- Fix a crash when using blocks without metadata, but with a block signature from the block runtime.

  Issue #106

- `PyObjCTools.MachSignals` likely hasn’t worked at all since PyObjC 2.0 because it uses a C module that was never ported to PyObjC 2.0. This private module is reintroduced in this release (with a slightly changed API)

  Issue #109

## Version 3.0.3

- Fix a number of OSX 10.10 support issues.

## Version 3.0.2

- Issue #99: Installation failed with recent versions of setuptools due to invalid assumptions in the PyObjC setup script.

- Issue #93: For a objc.PyObjCPointer object `ptr.pointerAsInteger` returned a 32-bit value on 64-bit systems.

- Issue #92: Removed dependency on pyobjc-framework-GameKit from the pyobjc package, GameKit isn’t packaged yet.

## Version 3.0.1

- Issue #86: Fix installation issue with setuptools 3.6.

- Issue #85: Remove debug output from the wrapper for `NSApplicationMain`.

- Issue #82: NSArray.__iter__ was accedently removed in PyObjC 3.0

- PyObjCTools.Debugging didn’t work properly on recent OSX versions (at least OSX 10.9) because `/usr/bin/atos` no longer worked.

## Version 3.0

- Issue #50: Accessing Objective-C methods on “magic cookie” variables, like `LaunchServices.kLSSharedFileListItemLast` would crash the interpreter.

  This affected code like:

      from LaunchServices import kLSSharedFileListItemLast

      kLSSharedFileListItemLast == kLSSharedFileListItemLast
      dir(kLSSharedFileListItemLast)
      kLSSharedFileListItemLast.compare_

- Added a decorator “python_method” than can be used to decorate methods that should not be registered with the Objective-C runtime and should not be converted to a Objective-C selector.

  Usage:

      class MyClass (NSObject):

          @python_method
          @classmethod
          def fromkeys(self, keys):
              pass

  This makes it easier to add a more “pythonic” API to Objective-C subclasses without being hindered by PyObjC’s conventions for naming methods.

- Issue #64: Fix metadata for `Quartz.CGEventKeyboardSetUnicodeString` and `Quartz.CGEventKeyboardGetUnicodeString`.

- Issue #77: Passing a bound selector as a block argument failed when the block was actually called because the trampoline that calls back to Python accidently ignored the bound `self` argument.

- Issue #76: It is now possible to pass `None` to a method expecting a block argument, as with normal object arguments the Objective-C method receives a `nil` value.

- Python integer values with values between 2 ** 63 and 2**64 are now proxied as plain NSNumber objects, not as using PyObjC specific subclass of NSNumber, to avoid a problem with writing them to binary plist files.

  This is a workaround and will likely be changed in some future version.

- `inspect.signature` works for all functions and methods implemented in C, when using Python 3.4 or later.

- The module `PyObjCTools.NibClassBuilder` is not longer available. It only worked with ancient versions of Interface Builder (pre-Xcode)

- The wrapper type for opaque pointers didn’t have a “__module__” attribute, which breaks code that (correctly) assumes that all types have such an attribute.

- Archiving now supports nested definitions and method references, simular to the support of those added to pickle protocol 4 in Python 3.4.

  Encoding nested classes requires support for the `__qualname__` attribute, and hence requires Python 3.3. Decoding should work with earlier python versions as well.

- Addd `objc.autorelease_pool`, a context manager for managing an autorelease pool. Usage:

      with objc.autorelease_pool():
         pass

  This is equivalent to:

      _pool = NSAutoreleasePool.alloc().init()
      try:
          pass

      finally:
          del _pool

- Added `objc.registerABCForClass` to make it possible to register a class with a number of ABC classes when the class becomes available.

- `NSDecimalNumber` can now be instantatiated as a normal Python object:

      value = NSDecimalNumber(4)

- `NSData` and `NSMutableData` can now be instantiated as a normal Python object:

         value = NSData(someBytes)

      or::

         value = NSData()

- `NSDecimal` now coerces the other value to `NSDecimal` in coercions. Because of you can now order instances of `NSDecimal` and `int`.

- `PyObjCTools.KeyValueCoding.ArrayOperators` and `PyObjCTools.KeyValueCoding.arrayOperators` were accidently public names in previous releases, and are now removed. Use the array operators in the KVC protocol instead.

- Restructured the “convenience” method code. This shouldn’t have user visible effects, but makes the code easier to maintain.

- `objc.addConvienceForSelector` no longer exists, it isn’t possible to provide this functionality with the current implementation of the bridge.

- The build of pyobjc-core can now be configured by editing setup.cfg (or providing arguments to the build_ext command), instead of editing the setup.py file.

  Currently the following options are availabel for the build_ext command:

  - `--use-system-libffi`: When this option is used the build will use /usr/lib/libffi.dylib instead of the embedded copy of libffi. The latter is the default is and is better tested.

  - `--deployment-target=VAL`: The value of `MACOSX_DEPLOYMENT_TARGET` to use, defaults to the deployment target used for building Python itself

  - `--sdk-root=VAL`: Path to the SDK root used to build PyObjC, or “python” to use the default SDK selected by distutils. The default is to use the most recent SDK available.

- The lazy importer has smarter calculation of the `__all__` attribute, which should speed up ‘from Cocoa import *’.

- BUGFIX: using a method definition with only `*args` and `**kwds` used to crash the interpreter, the now once again raise a TypeError exception.

- The metadata for pyobjc-framework-Accounts was incomplete, fixed that.

- `objc.callbackFor()` now also adds a __metadata__ method to decorated functions. This is primarily to make it easier to test the metadata values.

- The __typestr__ attribute of opaque pointer types is now a byte string, in previous versions this was an instance of `str` (this only affects Python 3 support)

- The JavaScriptCore bindings (in pyobjc-framework-WebKit) are now more usable because types like “JSValueRef” are now exposed to Python (they were missing due to incomplete metadata).

- Exclude a number of keys from the metadata dictionary when they have the default value (in the result from the __metadata__() method on methods and functions)

- The “lazy” modules used by framework wrappers now always have a `__loader__` attribute (as required by PEP 302). The value can be `None` when there is no explicit loader (such as when importing from the filesystem in Python 3.2 or earlier).

- Method (and function) metadata is stored in a more compact manner, reducing the memory use of PyObjC applications.

- Removed support for hiding “protected” methods, `objc.setHideProtected()` is gone, it complicated the code without real advantages.

  Reasons for this:

  - There were some conflicts because a class implemented two selectors that caused the same python method to be added to the class __dict__. Which one was added was basicly random.

  - The functionality required PyObjC to maintain a full __dict__ for classes, even when most Cocoa methods were never called. Ensuring that the contents of __dict__ is correct in the face of Objective-C categories and class patches required some very expensive code.

  As a side effect of this some classes may no longer have the convenience methods they had in earlier releases (in particular classes that are not mentioned in Apple’s documentation).

- Issue #3: The bridge now lazily looks for Objective-C methods as they are used from Python, instead of trying to maintain a class __dict__ that mirrors the method list of the Objective-C class.

  Maintaining the __dict__ was very expensive, on every method call the bridge would check if the method list had changed and there is no cheap way to perform that check.

  Note

  I haven’t done performance tests at this time, it is not yet clear if this work will make the bridge more efficient or that there are other more important bottlenecks.

- The default translation from a python name to a selector was slightly changed:

  - double underscores inside the name are no translated to colons, that is ‘foo__bar_’ is translated to ‘foo__bar:’, not ‘foo::bar:’

  - if the Python name start with two uppercase letters and an underscore, that first underscore is not translated into an colon. Two leading capitals are often used as a way to add some kind of namespacing to selector names (and avoid conflicts when a method with the same name is added later by the library provider)

- Added __new__ method to NSString, it is now possible to explictly convert a python string to a Cocoa string with `NSString(someString)`

- Added __eq__ and __ne__ methods to native selector objects, which mean you can now check if two method objects are the same using ‘sel1 == sel2’. This works both for bound and unbound selectors.

- NSData.bytes() could raise an exception on some version of Python 3 when the data object is empty. The function now returns an empty bytes object instead.

- NSMutableData.mutableBytes() raises an exception when the data object has a 0-sized buffer. (see also the previous bullet)

- Add attribute __objclass__ to `objc.selector` instances as an alias for definingClass. The name __objclass__ is used by builtin method objects for the same purpose as definingClass.

  The new attribute is needed to ensure that `help(NSObject)` works (although all methods are shown as data descriptors, not methods)

- :class`objc.selector` no longer implements __set__, which means it is now classified as a method descriptor by the `inspec` module, which gives nicer output in `pydoc`.

  This doesn’t change any functionality beyond that, it is still possible to overwrite methods and not possible to delete them.

- `objc.native_selector` and `objc.function` now have a (minimal) docstring with information object. This makes `help` for Cocoa classes and functions more useful.

  As a side-effect of this the docstring is no longer writeable.

  Note

  The docstring show the interface of a block with a function prototype instead of the proper C declaration, that makes the implementation slightly easier and the function prototype syntax is slightly easier to read for users that aren’t C experts.

- `objc.selector`, `objc.function` and `objc.IMP` now have an implementation for the “__signature__” property when using Python 3.3 or later. This makes it possible to use `inspect.signature()` with these objects.

- It should now be possible to write tuples with more than INT_MAX elements to an NSArchive. Those archives cannot be read back by older versions of PyObjC (or python running in 32-bit mode), but archives that contain only smaller tuples can be read back by earlier versions.

- Issue #38: Struct wrappers and opaque pointer types now implement support for `sys.getsizeof()`, as do `objc.FSRef`, `objc.FSSpec`, and Objective-C classes.

  The size of Objective-C instances is not entirely correct, and cannot be. The `sizeof` function only reports the size of the proxy object and the basic size of the Objective-C object. It does not report additional buffers used by the object, which for example means that a too low size is reported for Cocoa containers like NSArray.

- Opaque pointer objects now have a method “__c_void_p__” that returns a `ctypes.void_p` for the same pointer.

- Added an API to “pyobjc-api.h” that makes it easier to explicitly load function references in manual function wrappers. This replaces the compiler support for weak linking, which was needed because weak linking did not work properly with clang (Xcode 4.5.1). This also makes it possible to compile in support for functions that aren’t available on the build platform (in particular, when building on 10.8 the Quartz bindings now contain support for some functions that were dropped in 10.8 and which will be available through pyobjc when deploying to 10.7)

- The framework wrappers no longer export a “protocols” submodule. Those submodules were deprecated in 2.4 and did not contain information that is usefull for users of PyObjC.

- Dropped the “objc.runtime” attribute (which was deprecated in PyObjC 2.0)

- Dropped depcreated APIs objc.pluginBundle, objc.registerPlugin. Py2app has used a different mechanism for years now.

- Dropped deprecatd APIs: objc.splitStruct, objc._loadFunctionList. Both have been replaced by newer APIs in PyObjC 2.4.

- Foundation’s NSDecimal type is exposed in the objc module as well.

  This was done to remove a dependency from the pyobjc-core package to pyobjc-framework-Cocoa.

- The type `objc.NSDecimal` is now an immutable type, just like `decimal.Decimal` and other Python value types.

  Because of this the interface of `Foundation.NSScanner.scanDecimal_` has changed, in previous versions it is used as:

      dec = Foundation.NSDecimal()
      ok = scanner.scanDecimal_(dec)

  In the current version it is called just like any other method with an output argument:

      ok, dec = scanner.scanDecimal_(None)

- The C code is more careful about updating Python reference counts, in earlier versions it was possible to trigger access to a field in a datastructure that was being deallocated because the calls to `Py_DECREF` for the field happened before setting the field to `NULL` or a new value. This could then result in a hard crash due to accessing freed memory.

- Bugfix: objc.NSDecimal(2.5) works with python 3 (caused a confusing exception due to buggy code before).

- Bugfix: the support for `round` for `objc.NSDecimal` always rounded down, instead of using the normal rounding rules used by other methods.

- PybjC no longer supports the CoreFoundation bindings in the “Carbon.CF” module in the standard library for Python 2. The “Carbon.CF” module is not present in Python 3, and is unmaintained in Python 2.

- The ‘struct sockaddr’ conversion code now understands the AF_UNIX address family.

- The function “objc.setSignatureForSelector” has been removed (and was deprecated in 2.3), use the metadata system instead.”

- The ‘returnTypes’ and ‘argumentTypes’ parameters for ‘objc.selector’ have been removed (they were deprecated in version 2.5). These were an attempt to use type encodings as used in `Py_BuildValue()` and AFAIK were never used in real code.

- The header “pyobjc-api.h” has been cleaned up:

  Note

  “pyobjc-api.h” is used by extension modules in the PyObjC framework wrappers but is not intended to be a public API. Please let me (Ronald) know if you use this API, I’m trying to get the API as small as possible and that might lead to its complete removal in a future version of PyObjC.

  - Py_ARG_SIZE_T is no longer defined by pyobjc-api.h (use “n” instead)

  - Removed the following functions from the API (PYOBJC_API_VERSION is now 20) because they aren’t used by PyObjC:

    - PyObjC_PerformWeaklinking (and struct PyObjC_WeakLink)

    - PyObjCRT_RemoveFieldNames

    - PyObjC_is_ascii_string

    - PyObjC_is_ascii_prefix

    - PyObjCObject_Check

    - PyObjCClass_Check

    - PyObjCSelector_Check

    - PyObjCObject_ClearObject

    - PyObjCClass_New

    - PyObjCErr_ToObjC

    - PyObjC_RegisterSignatureMapping

    - PyObjCRT_AlignOfType

    - PyObjCRT_SELName

    - PyObjCRT_SimplifySignature

    - PyObjC_RegisterStructType

    - PyObjCObject_IsUninitialized

    - PyObjCObject_New

    - PyObjCCreateOpaquePointerType

    Note

    There will be futher cleanup of this API before the 3.0 release.

    Added a name argument to PyObjCPointerWrapper_Register.

- The KVO implementation for Cocoa subclasses used to ignore exceptions in the implementation of `[obj willChangeValueForKey:]` and `[obj didChangeValueForKey:]` and no longer does so.

  One side effect of this is that `willChangeForForKey_` and `didChangeValueForKey_` can now cause user visible exceptions when “__useKVO__” is true (the default) and these methods are implemented in Python.

- PyObjC 3 requires a compiler that supports Objective-C with C99 as the base language.

- PyObjC raises an exception instead of creating instances of `objc.PyObjCPointer` when you set `objc.options.unknown_pointer_raises` to `True`.

  The default is currently `False`, that will be changed in a future version and the entire objc.ObjCPointer class will likely be removed some releases after that.

- Configuration options are now attributes of special object `objc.options`.

  The following functions are therefore now deprecated and will be removed in PyObjC 3.1:

  - `objc.getVerbose()`

  - `objc.setVerbose()`

  - `objc.setUseKVOForSetAttr()`

  - `objc.setStrBridgeEnabled()`

  - `objc.getStrBridgeEnabled()`

- Removed objc._setClassSetUpHook, an internal method that is not used anymore.

- Removed +[OC_PythonObject setVersion:encoder:decoder:], +[OC_PythonObject pythonifyStructTable], +[OC_PythonObject depythonifyTable].

> All were private methods used by the core bridge and are no longer necessary.

- Added `objc.registerSetType()` and `objc.registerDateType()`, with simular semantics as the already existing functions `objc.registerMappingType()` and `objc.registerListType()`.

- Moved the logic for creating Objective-C proxies for Python objects from class methods on OC_PythonObject, OC_PythonArray, OC_PythonDictionary, OC_PythonSet and OC_PythonDate to a C function to simplify this logic and make it easier to further optimize.

  Because of this a number of (private) class methods are no longer available. This shouldn’t affect normal code because these methods aren’t part of the public API for PyObjC.

- Added bindings to the CoreWLAN framework (macOS 10.6 or later) in package “pyobjc-framework-CoreWLAN”

- Added bindings to the AVFoundation framework (macOS 10.7 or later) in package “pyobjc-framework-AVFoundation”

- The __dict__ for `anObject.pyobjc_instanceMethods` and `AClass.pyobjc_classMethods` is now read-only instead of read-write.

  Updates of __dict__ already did not affect anything (the value is calculated on access).

- Removed workarounds for KVO bugs in macOS 10.3.9, which means KVO will likely not work properly anymore on that release of OS X.

- Earlier versions of PyObjC accidently exposed `-[NSObject respondsToSelector:]` as `NSObject.respondsToSelector()` as well as the expected `NSObject.respondsToSelector_()`. The first incorrect binding no longer works.

- Python 3 only: NSKeyedArchives with a bytes object can now be read back by a pure Objective-C program (that program will decode it as an NSData object).

  Because of this the encoding for method for OC_PythonData was changed, archives created by PyObjC 3.0 can therefore not be read back by earlier PyObjC versions (but PyObjC 3.0 can read archives created by those older versions)

- NSKeyedArchives with a python list or tuple (but not subclasses) can now be read back as NSArrays in Objective-C programs.

- NSKeyedArchives with a python set or frozenset (but not subclasses) can now be read back as NSSets in Objective-C programs.

  This required a change in the format used to create the archive, which means that archives with a set or frozenset (but not subclasses) cannot be read back by earlier versions of PyObjC.

- When writing instances of list, tuple, dict, set and frozenset to an NSArchive, but not an NSKeyedArchiver, the objects are stored with the same encoding as the corresponding Cocoa class.

  This has two side effects: the archive can be read back by pure Objective-C code and when you read back the archive using PyObjC you’ll get instances of Cocoa classes instead of the native python classes.

- `-[OC_PythonEnumerator nextObject]` now returns `[NSNull null]` instead of `nil`, to be compatible with the behavior of item getters/setters and to avoid ending iteration premature when a Python sequence contains `None`.

- Fixed a number of issues with `None` as a member of a set-like object proxied by `OC_PythonSet`. The easiest way to trigger the issue in earlier versions:

      assert {None} == NSSet.setWithArray([None])

  These expose sets with the same members to ObjC code, but those objects didn’t compare equal.

- Python 2 only: NSDictionary instances now have the same internal other as dict instances with the same value, that is `cmp(anNSDict1, anNSDict2) == ``cmp(dict(anNSDict1), dict(anNSDict2))`.

- In previous versions of PyObjC instances of `Foundation.NSDecimal` behaved as if they had the same methods as `Foundation.NSDecimalNumber`. In 3.0 PyObjC no longer exposes these methods.

- Python blocks (that is, Python callables passed to a method/function that expects an Objective-C block argument) now include an Objective-C signature string (introduced in “ABI.2010.3.16”).

- PyObjC now supports blocks that have a large struct as the return value (for example a block that returns an NSRect structure).

- Reduced the number of unnecessary methods implemented by the various OC_Python* classes, this might affect some Objective-C code that directly uses these classes instead of just using the interface of their superclasses.

- `del NSObject.__version__` crashed the interpreter because the setter didn’t guard against deletion attempts.

- `del aSelector.isHidden` crashed the interpreter (see above)

- Class `objc.ObjCPointer` was not exposed in the `objc` module.

- The implementation of `objc.ObjCPointer` didn’t have a proper implementation of __getattribute__ and that made objects of this class even more useless than they should have been.

- Values of `objc.ObjCPointer` no longer have an unpack method (the method has been inaccisible for several releases and its implementation as unsafe)

- The type attribute of `objc.ObjCPointer` now starts with `objc._C_PTR` (that is, the type attribute is the encoded type of the pointer, instead of the encoded type of the pointed-to value).

- Framework wrappers no longer have a ‘protocols’ submodule, use `objc.protocolNamed()` to access a protocol.

- `-[OC_PythonObject valueForKeyPath:]` and `-[OC_PythonObject setValue:forKeyPath:]` now call helper functions in `PyObjCTools.KeyValueCoding`, just like `-[OC_PythonObject valueForKey:]` and `-[OC_PythonObject setValue:forKey:]`.

  This should give better results in some edge cases when dealing with complicated keypaths.

## Version 2.5.2

- “easy_install pyobjc” always tried to install the FSEvents binding, even when running on OSX 10.4 (where that API is not available).

- `objc.ObjCPointer` didn’t implement __getattribute__.

  (reported by private mail)

- Implementing a python method that has a block as one of its arguments didn’t work. It now works when there is metadata that describes the method signature.

  (reported by private mail)

- BUGFIX: a method definition like this now once again raises TypeError instead of crashing the interpreter:

      def myMethod(*args):
         pass

  (reported by private mail)

## Version 2.5.1

- PyObjC could crash when calling a method that is dynamicly generated (that is, the selector is not present in the class according to the Objective-C runtime but the instance responds to it anyway).

  The cases that used to crash now raise `objc.error` instead.

  Note

  It is highly unlikely that real code would run into this, found while working on PyObjC 3.x.

- When writing a python unicode object to an NSArchiver or NSKeyedArchiver the object is now stored exactly the same as a normal NSString, and will be read back as such.

  This increases interoperability with code that expects to read back a non-keyed archive in a different proces. An example of this is the use of Growl (see issue #31)

  Instances of subclasses of unicode are not affected by this change, and can only be read back by other PyObjC programs.

- Issue #43: It was no longer possible to create instances of LaunchServices.LSLaunchURLSpec due to incomplete metadata.

- Issue #41: the ‘install.py’ script in the root of pyobjc repository failed to perform an install when running in a clean checkout of the tree.

- Issue #44: the various Cocoa frameworks only export @protocol defintions when they happen to be used by code in the framework. Added extensions to the various framework wrappers to ensure that all protocols are available to python code.

- Opaque pointer types now can be constructed with a “c_void_p” keyword argument that contains a `ctypes.c_void_p` value for the pointer.

  This is the reverse of the __c_void_p__() method that was added earlier.

- Issue #46: It was not possible to use the Quartz.CoreGraphics module on OSX 10.5 when the binary was build on 10.8 (and using a 10.5 deployment target).

  Simular issues may be present in some of the other framework wrappers, there will be a more generic fix for this issue in a future release.

## Version 2.5

- Add conversion to/from ctypes.c_void_p to proxies for Cocoa objects.

  To use:

      anObject = NSArray.array()
      void_p = anObject.__c_void_p__()
      # use void_p with ctypes

      otherObject = NSObject(c_void_p=voip_p)
      assert anObject is otherObject

  Note that it is save to contruct the python proxy from NSObject, the class will return an instance of the correct proxy type (in this example an instance of NSArray)

- Fixed problem where the result of `anObject.__cobject__()` could not be converted back to a PyObjC object again.

- A number of framework wrappers have a “protocols” submodule containing protocol objects (for example the module ‘Foundation.protocol’). Use of these modules is deprecated, they will be removed in PyObjC 3.0.

  Use `objc.protocolNamed()` to access protocols instead.

- Instances of `objc.ivar` now have slots for introspection:

  - __typestr__: The type encoding

  - __name__: The Objective-C name

  - __isOutlet__: `True` if the instance variable is an IBOutlet

  - __isSlot__: `True` if the instance variable is a Python slot

- Added implementation of ‘==’ and ‘!=’ for selectors defined in Python that is slightly smarter than the default (identity based) implementation in Python.

  This is mostly done for the PyObjC unittests and shouldn’t affect user code.

- Issue #30: Explicitly check if the compiler works, and try to fall back to clang if it doesn’t. This uses a simular algoritm as the fix for <https://bugs.python.org/issue13590> in Python’s tracker.

- Issue #22: Reimplement support for bridgesupport files

  This reintroduces `objc.parseBridgeSupport` and `objc.initFrameworkWrapper`, both are reimplemented in Python (previous version used C code)

  Note

  The implementation is currently barely tested and therefore likely contains bugs.

- Struct types created by the framework wrappers once again create class methods on `objc.ivar` to generate instance variables of that type:

      myLocation = objc.ivar.NSPoint()

  This has the same result as:

      myLocation = objc.ivar(typer=NSPoint.__typestr__)

- `objc.IBAction()` now raises TypeError when the argument is `None`.

- `objc.instancemethod()` is now actually exported by the `objc` package.

- `objc.accessor()` and `objc.typedAccessor()` were not 64-bit safe.

- `objc.accessor()` and `objc.typedAccessor()` didn’t support the entire set of KVC accessors.

- Add methods “_asdict” and “_replace” and field “_fields” to the struct wrapper types. These new attributes mirror the `collections.namedtuple` interface.

  Note

  In the long run I’d like to make struct wrappers immutable to allow using them as dictionary keys. This is a first step in that direction and makes it possible to verify that immutable struct wrappers are useable.

- Added `objc.createStructAlias()`, and deprecated `objc.registerStructAlias()`. The new function has a “name” argument and can register types with the `objc.ivar` type (see previous item)

- Add explicit deprecation warnings to `objc.CFToObject` and `objc.ObjectToCF`. Both functions barely function at all and will be removed with PyObjC 3.0.

- `objc.CFToObject` and `objc.ObjectToCF` are no longer available when using Python 3.x, the APIs are used for MacPython support and that part of the standard library is not available with Python 3.x.

- `objc.splitStruct` is renamed to `objc.splitStructSignature` and now actually works. The old name is temporarily available as an alias.

- Fix refcounting leak in `objc.splitSignature`.

- `objc._loadFunctionList` is renamed to `objc.loadFunctionList` and is fully documented. The old name is temporarily available as an alias.

- Move (deprected) decorator “signature” from objc._functions to objc._descriptors, and remove the former module.

  Note

  The names op submodules of objc are implementation details, don’t import them directly.

- The optional argument for the decorator `objc.selectorFor()` was broken

- The `PyObjCTools.KeyValueCoding.kvc` wrapper __setattr__ wrapper incorrectly set attributes on itself as well as on the wrapped object (the latter using Key-Value Coding)

- Renamed (private) function injectSuffixes to inject_suffixes to match the other code in objc._dyld.

- Slight restructuring of objc._pythonify to reduce code duplication between the python 2.x and python 3.x cases.

- Removed deprecated methods from PyObjCTools.TestSupport

- `collections.Sequence` objects are now automaticly proxied as NSArray instances

- `collections.Mapping` objects are now automaticly proxies as NSDictionary instances

- Removed some objects and functions from objc._bridges that weren’t public and weren’t used by PyObjC itself:

  - BRIDGED_STRUCTURES: mapping of python type to proxy class

  - BRIDGED_STRUCTURES2: mapping of python type to proxy class (not used at all)

  - BRIDGED_TYPES: mapping of python type to proxy class

  - _bridgePythonTypes: uses BRIDGED_STRUCTURES and BRIDGED_TYPES to update bridge data

  _bridgePythonTypes was called unconditionally, but never did anything because the data structures were empty and no code adds anything to them.

- Improved documentation

- For Objective-C blocks: try to extract the block signature from the (Objective-)C runtime when there is no metadata for the block. The block signature is available only when the code that creates the block is compiled using a recent enough compiler (although “recent enough” is fairly old by now)

- Fixes some issues with `objc.object_property` which were found by improved unittests. In particular:

  - The selector names for boolean properties were wrong

  - Properties with a “depends_on” list didn’t inherit properly

  - Properties that were used in subclasses didn’t generate the correct KVO events when they were observed.

  - KVO issues with computed (read-only) properties

- Fixed some issues with `objc.array_property` and `objc.set_property` that were found by much improved unittests.

- Fixed issues with `PyObjCTools.KeyValueCoding` that were found by improved unittests:

  - `getKey` didn’t work propertly on dictionaries (dictionaries were treated as sequences)

  - `getKeyPath(list, "@avg.field")` didn’t work when field wasn’t a valid key for all

      items in the list, and likewise for the ‘@sum’, ‘@min’, ‘@max’ special keys.

  - `getKeyPath` didn’t raise the correct exception for empty key paths

  - `@unionOfObjects` and `@distinctUnionOfObjects` operators for Python sequences didn’t raise an exception when the selected keypath didn’t exist on an item of the sequence.

  - `@unionOfArrays` and `@distinctUnionOfArrays` operators for Python sequences didn’t raise an exception when the selected keypath didn’t exist on an item of the sequence.

  - `@distinctUnionOfArrays` and `@distinctUnionOfObjects` didn’t work properly when

      the keypath pointed to objects that weren’t hashable.

  - `@distinctUnionOfSets` operator was not present at all.

- ‘PyObjCTools.KeyValueCoding.setKey’ now sets keys in dictionaries, that is:

      >>> a = {}
      >>> setKey(a, 'foo', 42)
      >>> a
      {'foo': 42 }

- ‘PyObjCTools.KeyValueCoding.setKey(object, ‘key’, value)’ now sets attribute ‘key’ when the object already has that attribute, before looking at ‘_key’. This avoids that `setKey` changes the underlying storage for a common Python property pattern:

      class Record (object):
         @property
         def prop(self):
             return self._prop

         @prop.setter
         def prop(self, value):
             self._prop = calculate_using(value)

  Until PyObjC 2.5 the property setter for ‘prop’ would not be called when using KeyValueCoding.

- Removed macOS 10.2 (!) compatibility from `PyObjCTools.KeyValueCoding`.

- PyObjCTools.KeyValueCoding has undocumented attributes ‘ArrayOperators’ and ‘arrayOperators’, both will be removed in a future release.

- Using NSArchiver or NSKeyedArchiver to encode and then decode a python list or tuple could result in an unexpected value. In particular, if any element of the sequence was `None` before archiving it would by `NSNull.null()` when read back.

- Using NSArchiver or NSKeyedArchiver to encode and decode (pure) python objects didn’t always work correctly. Found by improved unittests.

- Using NSArchiver or NSKeyedArchiver to encode and decode bytes objects in Python 3 would result in an instance of NSData instead of bytes.

- The implementation of cmp() for NSSet instances now matches the behavior of regular python sets, that is calling `cmp(anNSSet, aValue)` will raise a TypeError exception unless both arguments are the same object (`anNSSet is aValue`).

- Issue #36: explictly document that PyObjC does not support the Objective-C Garbage Collection system (introduced in OSX 10.5, deprecated in OSX 10.8), and also mention this in the documentation for the screen saver framework because the screen saver engine uses GC on OSX 10.6 and 10.7.

- Issue #37: Fix runtime link error with EPD (Enthought Python Distribution), which doesn’t include the pymactoolbox functionality.

- Various improvements to the documentation

## Version 2.4.1

Note

2.41 was never released, all bugfixes are in the 2.4 branch as well as the 2.5 release.

- Cocoa wrappers: fix metadata for `copy`, `mutableCopy`, `copyWithZone:` and `mutableCopyWithZone:`

- Fix for issue 3585235 on SourceForge: the threading helper category on NSObject didn’t work due to a typo (defined in the Cocoa bindings)

  Fix is based on a patch by “Kentzo” with further updates and tests by Ronald.

- Rename ReadMe.txt to README.txt to work around misfeature in the sdist command in distutils.

- Issue #28: Avoid crash when using CGEventTabProxy values.

- Issue #33: “easy_install pyobjc” no longer tries to install the InterfaceBuilderKit bindings on OSX 10.7 or later.

## Version 2.4

Note

Sadly enough this changelog is incomplete.

- Fix crash when unarchiving a Python object.

- Add missing calls to `[super init]` in the implementation of OC_PythonUnicode and OC_PythonString (the ObjC proxies for python’s unicode and str types)

- `objc.addConvenienceForSelector` is deprecated, primarily to make it possible to restructure the pyobjc internals.

- Workaround for bug in pip that resulted in pyobjc-core not being pip installable. Patch by Marc Abramowitz.

- Creating new formal protocols now uses the new runtime API that was introduced in OSX 10.7. Because of this it is now possible to create new formal protocols in 64-bit code (when running on OSX 10.7 or later)

- Codebase should work again when Python using `--enable-unicode=ucs4`.

- BUG: Avoid crashes in calculating with NSDecimal values in Python 3

- Implement ‘//’ operator for NSDecimal and NSDecimalNumber.

- Implement support for the `round` builtin in NSDecimal and NSDecimalNumber

- There is now limited support for packed struct definitions. This requires that the struct is wrapped using `objc.createStructType`.

  Struct packing is not described in the encoding string for a structure, which is why special support is needed.

- objc.registerStructAlias now returns the alias type instead of `None`

- In Python 3.x there is a new way to explicitly specify which (informal) protocols a class conforms to:

      class MyClass (NSObject, protocols=[Protocol1, Protocol2]):
         pass

  Python 2.x does not support this syntax, you can still use the following code there:

      class MyClass (NSObject, Protocol1, Protocol2):
         pass

  Note: The Python 2.x style works upto Python 3.2. In Python 3.3 and later the Python 2.x style declaration no longer works due to changes in the language.

- It is also possible to specify the protocols that a class conforms to using a “__pyobjc_protocols__” attribute in the class body. This has the same interface as the “protocols” keyword argument in Python 3.x.

  This is primarily meant to be used by code that needs to work in Python 2 as well as Python 3.

- Updated Python support. With this release PyObjC supports Python 2.6 and later, including Python 3.3 (which has a completely new representation for unicode strings)

  NOTE: Support for 3.3 is very much work in progress right now, there have been changes for the new unicode representation, but more changes are required.

  Known issues:

  - metadata conflict error when explictly implementing a prototype

  - one test failure w.r.t. unichar argument arrays

  Futhermore there are two refcounting test failures in both 3.2 and 3.3

- Add `objc.setObjCPointerIsError` and `objc.getObjCPointerIsError`.

  By default PyObjC will create a `PyObjCPointer` object when it tries to convert a pointer it doesn’t know about to Python. These values are fairly useless and obvious an indication that an API is wrapped improperly.

  With `objc.setObjCPointerIsError(True)` you can tell the bridge to raise an exception instead of creating these values.

- -[OC_PythonNumber compare:] calls super when the other value is an NSNumber and the Python value can be represented using a basic C type.

  This could slightly affect the results of comparing Python and Cocoa numbers, and avoids unbounded recursion when comparing Python numbers with NSDecimalNumbers on OSX 10.7 or later.

- Add implementations for methods from the NSComparisonMethods informal protocol to OC_PythonNumber

- Add ‘__cmp__’ method when the Objective-C class implements the ‘compare:’ selector.

- Introduced a way to compile bridgesupport data and lazily load wrappers.

  Avoid using “from Cocoa import *” to get the most benefits from this, use either “import Cocoa” or “from Cocoa import NSObject”.

- `objc.initFrameworkWrapper` is now deprecated, switch to the new compiled metadata code instead.

- `objc.allocateBuffer` now returns a bytearray on python >= 2.6, it used to return a buffer object in Python 2.

- `objc.FSRef.from_pathname` actually works instead of always raising

    a TypeError.

- `objc.getAssociatedObject`, `objc.setAssociatedObject` and `objc.removeAssociatedObjects` are wrappers for the corresponding functions in the Objective-C runtime API. These functions are only available when PyObjC was build on a system running OSX 10.6 or later, and the script is also running on such as system.

  The `policy` argument for `objc.setAssociatedObject` is optional and defaults to `objc.OBJC_ASSOCIATION_RETAIN`.

## Version 2.3

- Add some experimental code that slightly reduces the amount of memory used when loading bridgesupport files.

  Futher work is needed to investigate what causes the memory usage to increase as much as it does, sadly enough Instruments doesn’t play nice with `--with-pymalloc` and for some reason ‘import Foundation’ crashes with `--without-pymalloc`.

- “<struct>” definitions in the bridgesupport files can now have an alias attribute containing the name of Python type that should be used to proxy values of this type.

  This is used in the Quartz bindings to ensure that `CGRect` and `NSRect` (from the Foundation framework) map onto the same Python type.

- Added `objc.registerStructAlias`, a helper function to add a type encoding that should map on an already existing struct type.

- Use this to ensure that `NSRect` and `CGRect` are the same (in the Foundation and Quartz bindings).

- This version requires Python 2.6 or later, and also supports Python 3.1 or later.

- BUGFIX: The generic proxy for Python objects now implements `-(CFTypeID)_cfTypeID`, which should result in less hard to understand Objective-C exceptions.

- BUGFIX: The metadata file support now checks if the metadata is compatible with information gathered from the Objective-C runtime.

  This ensures that when a native method signature is incompatible with the signature in a metadata file the brige won’t garble the correct information (and that in turn avoids hard crashes).

- PyObjC’s support for `NSCoding` now also works with plain `NSArchiver` instances, not just with `NSKeyedArchiver`.

- (This item is currenlty only true for python3, need tests for python 2.x)

  NSDictionary now fully implements the dict API, except for the differences not below:

  - `NSDictionary` doesn’t have the `__missing__` hook.

  - `NSDictionary` always copies keys, which gives slightly different

      semantics from Python.

  - `NSDictionary.copy` always returns an immutable dictionary, use `NSDictionary.mutableCopy` to get a mutable dictionary.

  - Instances of `NSDictionary` cannot be pickled

  `NSDictionary` implements one important feature that native Python dictionaries don’t: full support for Key-Value Observations. Sadly enough it is not possible to support Key-Value Observation of native Python dictionaries without patching the interpreter.

- NSSet and NSMutableSet implement the same interface as `frozenset` and `set`, except for the differences listed below:

  - `NSSet.copy` and `NSMutableSet.copy` always return an immutable

      object, use the `mutableCopy` method to create a mutable copy.

  - Instances of `NSSet` cannot be pickled

  - In-place operators are not implemented, which means that `aSet |= value` will assign a new object to `aSet` (as if you wrote `aSet = aSet | value`.

    This is needed because the bridge cannot know if if `aSet` is mutable, let alone if `aSet` is a value that you are allowed to mutate by API contracts.

  - It is not possible to subclass `NSSet` and `NSMutableSet` in the same way as Python’s `set` and `frozenset` classes because the Cocoa classes are class clusters (which means that all instances of `NSSet` are actually instances of, non-necessarily public, subclasses.

  - Sadly enough `set([1,2,3]) == NSSet([1, 2, 3])` evaluates to False, even though the values are equavalent. Reversing the order of the test (`NSSet([1, 2, 3]) == set([1,2,3])`) results in the expected result.

    This is caused by the way equality tests for sets are implemented in CPython and is not something that can be fixed in PyObjC.

- BUGFIX: accessing methods through `anObject.pyobjc_instancMethods` is now safer, before this release this could cause unlimited recursion (although I’m not sure if it was possible to trigger this without other changes in this release).

- The PyObjC egg now includes the header files that should be used to compile to compile the extensions in the framework wrappers, which makes it a lot easier to access those headers.

- BUGFIX: The definition for Py_ARG_SIZE_T was incorrect, which causes problems in 64-bit code.

- Initial port to Python 3.x

  C-style ‘char’ characters and ‘char*’ strings are translated to/from byte strings (‘str’ in Python 2.x, ‘bytes’ in Python 3.x). There is no automatic translation from Unicode strings.

  Objective-C selector names and encoded type strings are byte strings as well.

  NOTE: Python 3 support is pre-alpha at this time: the code compiles but does not pass tests yet. The code also needs to be reviewed to check for python3<->objc integration (dict.keys now returns a view, NSDictionary.keys still returns a basic iterator, …)

  TODO:

  - Implement new style buffer support when depythonifying an array of C structures.

  - Documentation updates

- The Python 3.x port does not support transparent proxies for ‘FILE*’ “objects” because the `file` type in Python3 is not implemented on top of the C library stdio.

- The Python 2.x port has been enhanced to accept Unicode strings in more locations.

- Implement support for PEP-3118, for both Python 2.x and Python 3.x.

  This means that proxying arrays of basic C types to ObjC can now make use of the extended type information provided by the PEP-3118 API.

  Furthermore it is possible to use `memoryview` objects with `NSData` instances, with the limitation that the memoryview must be cleaned up before the currently active autorelease pool is cleared, or the data instance is resized. That’s a result of API restrictions in Apple’s frameworks.

- The PyObjCTest testsuite now supports version-specific tests: for Python 2.x it will load modules whose name starts with ‘test2_’ and for Python 3.x those starting with ‘test3_’. For both versions it will load test modules whose name starts with ‘test_’ as well.

- Renamed the assertion functions in `PyObjCTools.TestSupport`, added `assertFoo` methods and deprecated the `failIfFoo` and `failUnlessFoo` methods (simularly to what’s happening in the stdlib).

- Added `objc.propertiesForClass`. This function returns information about properties for a class from the Objective-C runtime. The information does not include information about properties in superclasses.

- Added `objc.object_property`. This is class behaves simularly to `property`, but integrates better with Objective-C code and APIs like Key-Value Observation.

- Added `objc.array_property`. This is simular to `objc.object_property`, but models a list-like object and implements the right Objective-C interfaces for Key-Value Coding/Observations.

- Added `objc.set_property`. This is simular to `objc.object_property`, but models a set-like object and implements the right Objective-C interfaces for Key-Value Coding/Observations.

- Added `objc.dict_property`. This is simular to `objc.object_property`, but models a dict-like object and implements the right Objective-C interfaces for Key-Value Coding/Observations.

- NOTE: The interfaces of `array_property`, `set_property` and `dict_property` are minimal w.r.t. options for tweaking their behaviour. That will change in future versions of PyObjC.

  Please let us know which hooks would be usefull.

- The documentation is now written using Sphinx.

  NOTE: This is an operation in progress, the documentation needs work to be truly usefull.

- The (undocument) module `PyObjCTools.DistUtilsSupport` is no longer present.

- Converting a negative value to an unsigned integer now causes a deprecation warning, this will be a hard error once I update all framework wrapper metadata.

## Version 2.2 (2009-11-24)

- BUGFIX: Ensure PyObjC compiles cleanly with Python 2.6.4.

- BUGFIX: It is now possible to explicitly define `__getitem__` (and other special methods) if your class implements `objectForKey:`:

      class MyObject (NSObject):
          def objectForKey_(self, k):
             pass

          def __getitem__(self, k):
             pass

  In previous version of PyObjC the implementation of `__getitem__` would silently be replaced by a generic one.

- The default value for the `__useKVO__` attribute in class definitions can now be controlled by `objc.setUseKVOForSetattr(b)`. The default is `True`.

  Note: in previous versions the default was `False`.

  Note2: the `__useKVO__` attribute is an implementation detail and should not be used in normal code.

  This change fixes an issue where KVO failed to detect some changes when those changes were done in Python using attribute access syntax.

- Wrappers for `objc_sync_wait`, `objc_sync_notify` and `objc_sync_notifyAll` have been removed. These have never been part of the public API and this should therefore not affect existing code.

- BUGFIX: There was a refcount leak in the code that proxies native code to Python. This causes refcount leaks in user code when a Python class is instantiated from native code, when that class has an initializer written in Python.

  Thanks to Dirk Stoop of Made by Sofa for providing the bugreport that helped fix this issue.

- `objc.recycleAutoreleasePool` is now a no-op when a python bundle is loaded in an Objective-C program and the PyObjC’s global release pool gets drained by an outer release pool. This should not affect user programs.

- BUGFIX: Storing pure python objects in a `NSKeyedArchiver` archive didn’t full work for all tuples, especially self-recursive tuples.

  The current support for archiving Python objects passes all pickle unittests in Python 2.7.

- BUGFIX: `+new` is supposed to return an already retained object (that is, the caller owns a reference). Until now PyObjC has assumed that the return value of `+new` is an autoreleased value. The same is true for all class methods whose name starts with `new`.

- There is initial support for Objective-C blocks, based on the implementation description in the clang repository. Blocks are represented in Python as callable objects. This means you can pass an arbitrary callable when an Objective-C argument is a block, and that when your method accepts a block it will get passed a callable object.

  There are some limitations on the usage of blocks due to lack of introspection in the current implementation of blocks. This has two side-effects:

  - There must be metadata to describe the signature of blocks in PyObjC’s metadata XML files.

  - Block metadata is not retained when a block is stored in an ObjC datastructure, such as an `NSArray`, and there are no direct references to the block from Python.

- `objc.inject` is no longer support. This was code that had no real relation to the rest of PyObjC and was only working in 32-bit mode with little reason to expect that it would ever be ported to 64-bit mode.

- Move the testsuite from `objc.test` to `PyObjCTest` and no longer install the tests.

  The tests are no longer installed because they aren’t needed for day-to-day usage of PyObjC. Furthermore this change will make it possible to copy all of the pyobjc-core “egg” into an application bundle without adding unnecessary files to that bundle.

- BUGFIX: Storing pure python objects in a `NSKeydArchiver` archive didn’t work 100% reliably for Python floats. I’ve changed the implementation on for encoding floats a little and now floats do get rounddtripped properly.

  The side effect of this is that archives written by PyObjC 2.2b2 or later cannot always be read by earlier versions (but PyObjC 2.2b2 can read archives created with earlier versions).

- BUGFIX: Enable building from source with the Python.org binary distribution.

- BUGFIX: Fix crash when using the animotor proxy feature of CoreAnimation. That is, the following code now works:

      1 app = NSApplication.sharedApplication()
      2 window = NSWindow.alloc().init()
      3 anim = window.animator()
      4 anim.setAlphaValue_(1.0)

- Improve handling of non-methods in objc.Category:

  - The docstring of a category is now ignored

  - You’ll get an explict error exception when trying to add and `ivar` to a class

  - It’s now possible to add class attributes in a category:

        1   class NSObject (objc.Category(NSObject)):
        2       aClassDefault = [ 1, 2, 3 ]
        3
        4       @classmethod
        5       def getDefault(cls):
        6           return cls.aClassDefault

- Fixed support for `FSRef` and `FSSpec` structures.

  - Transparently convert `Carbon.File.FSRef` and `Carbon.File.FSSpec` instances to C.

  - The types `objc.FSRef` and `objc.FSSpec` are the native PyObjC representation for `FSRef` and `FSSpec` structures.

- Added more magic signature heuristics: the delegate selector for sheets is now automaticly recognized, removing the need for the decorator `AppHelper.didEndSelector` (which will stay present for backward compatibility).

  FIXME: Do the same thing for `objc.accessor`. Both are a frequent source for errors.

- Added `PyObjC.TestSupport`. This is an unsupported module containing useful functionality for testing PyObjC itself.

- Added `free_result` attribute to the `retval` element in metadata files. When this attribute has value `'true'` the return value of the C function (or ObjC-method) will be free-ed using the function `free()`, otherwise the bridge assumes other code is reponsible to free the result.

  This is to be used for low-level C API’s that return a pointer to a dynamicly allocated array that is to be free-ed by the caller. One example is the function `DHCPClientPreferencesCopyApplicationOptions` in the SystemConfiguration framework.

- Added `objc.context`, which is helpfull for dealing with “context” arguments as used by several Cocoa APIs. The context argument must be a number in Python, while you’d prefer to pass in an arbitrary object instead. The `objc.context` registry allows you to get a context integer for an arbitrary Python object, and retrieve that later on.

  To get the context integer for a Python object:

      ctx = objc.context.register(myValue)

  To unregister the object when you no longer need the context integer:

      objc.context.unregister(myValue)

  To retrieve the Python object given a context integer:

      myValue = objc.context.get(ctx)

  NOTE: This API is particularly handy when using Key-Value Observing, where the context number should be a unique value to make ensure that KVO usage by the superclass doesn’t get confused with your own usage of KVO.

- PyObjC can now run in 64-bit mode.

  NOTE: 64-bit support is beta quality, that is: all unittests pass, but I haven’t tried running real programs yet and hence there might be issues lurking below the surface.

  NOTE: 64-bit support does not yet work on PPC due to a bug in libffi which prefents catching Objective-C exceptions.

  This requires Leopard (OSX 10.5), earlier version of the OS don’t have a 64-bit Objective-C runtime at all. This currently also requires a copy of python that was build with `MACOSX_DEPLOYMENT_TARGET=10.5`.

  Note that class posing (the `poseAsClass_` class method) is not supported in 64-bit mode. It is also not possible to create new protocols in 64-bit code. Neither are supported by the 64-bit runtime APIs (that is, it is a restriction in Apple’s Objective-C 2.0 runtime).

- There now is a custom proxy class for instances of `datetime.date` and `datetime.datetime`, which takes away the need to manually convert these instances before using them from Objective-C (such as using an `NSDateFormatter`)

- Objective-C classes that support the `NSCopying` protocol can now be copied using `copy.copy` as well.

- `OC_PythonArray` and `OC_PythonDictionary` now explicitly implement `copyWithZone:` and `mutableCopyWithZone:`, copies will now be Python objects instead of regular `NSDictionary` instances.

- Pure Python objects now support the `NSCopying` protocol.

- A new decorator: `objc.namedselector` for overriding the Objective-C selector. Usage:

      1class MyObject (NSObject):
      2
      3    @objc.namedselector("foo:bar:")
      4    def foobar(self, foo, bar):
      5        pass

- A number of new type signature values were added. These are not present in the Objective-C runtime, but are used to more precisely describe the type of some arguments.

  The new values are:

  - `_C_UNICHAR`: A “UniChar” value in Objective-C

  - `_C_NSBOOL`: A “BOOL” value in Objective-C

  - `_C_CHAR_AS_INT`: A “char” in Objective-C that is used as a number

  - `_C_CHAR_AS_TEXT`: A “char” in Objective-C that is used as a character

  PyObjC will automaticly translate these values into the correct Objective-C type encoding when communicating with the Objective-C runtime, making this change transparent to anyone but Python users.

  NOTE: `_C_CHR` is of course still supported, with the same semi-schizofrenic behaviour as always.

  NOTE2: The non-standard metadata extensions we used before to indicate that a C short is used as a unicode string are no longer supported.

- Output arguments are no longer optional. They must be specified both in method implementations and method calls. In PyObjC 2.0 they were optional, but raised a deprecation warning, for backward compatiblity with PyObjC 1.x.

  The backward compatibility code was removed because it made code more complicated and actually caused some bugs.

- In PyObjC 1.x you could redefine an Objective-C class, as long as you redefined it in the same module (such as by reloading a module). That functionality didn’t work in PyObjC 2.0 and is now completely removed because the functionality isn’t supported by the Objective-C 2.0 runtime.

- Adds custom wrappers for some more Python types:

  - `OC_PythonNumber`: wraps python numeric types

    This is used instead of `NSNumber` because we might loose information otherwise (such as when using custom subclasses of `int`).

  - `OC_PythonSet`: wraps a python set and is a subclass of `NSMutableSet`

- BUGFIX: `OC_PythonEnumerator` now actually works.

- BUGFIX: using the `@throw` syntax one can raise arbitrary objects as exceptions (not just instances of NSException) in Objective-C. All instances of NSObject are now converted to Python exceptions, throwing some other object (such as a C++ exception) will still case a fatal error due to an uncaught exception.

  (SF Bug: 1741095)

- BUGFIX: `repr(CoreFoundation.kCFAllocatorUseContext)` now works

  (SF Bug: 1827746)

- BUGFIX: The wrappers for CoreFoundation types no longer create a new type in the Objective-C runtime, that type wasn’t used anywhere and was an unwanted side-effect of how CoreFoundation types are wrapped.

- BUGFIX: The docstring for newly defined methods is no longer hidden by PyObjC. That is, given this code:

      1   class MyObject (NSObject):
      2       def doit(self):
      3           "do something"
      4           return 1 + 2

  `MyObject.doit.__doc__` now evaluates to `"do something"`, in previous versions of PyObjC the docstring was `None`.

- BUGFIX: Fixed calling and implementation methods where one or more of the arguments are defined as arrays, like this:

      -(void)fooCallback:(NSRect[4])rects;

  There were various issues that caused these to not work correctly in all earlier versions of PyObjC (which wasn’t noticed earlier because Apple’s frameworks don’t use this construction).

- BUGFIX: correctly select the native implementation of the compatiblity routines for the ObjC 2.0 runtime API when running on 10.5 (when compiled for OSX 10.3 or later).

- BUGFIX: fix a number of compatibility routines (ObjC 2.0 runtime API on OSX 10.4 or earlier).

## Version 2.0.1 (included with OSX 10.5.2)

- BUGFIX: `objc.inject` works on Leopard (at least on Intel Macs, haven’t tested on PPC).

- BUGFIX: don’t crash when printing CF objects that are magic cookies.

- BUGFIX: It is now possible to override `respondsToSelector:` in Python.

- Add support for interacting with ‘@synchronized’ blocks in Objective-C.

  The function `object_lock(object)` is a contextmanager that acquires and releases the ‘@synchronized’ mutex for an object, and can also be used manually.

  That is (as context manager):

      1   from __future__ import with_statement
      2
      3   obj = NSObject.new()
      4
      5   with objc.object_lock(obj):
      6      # Perform work while owning the @synchronize lock
      7      pass

  or (manually):

      1   obj = NSObject.new()
      2   mutex = objc.object_lock(obj)
      3   mutex.lock()
      4   try:
      5       # Perform work while owning the @synchronized lock
      6       pass
      7   finally:
      8       mutex.unlock()

  Note that the first version is slightly saver (see the documentation for with-statements for the details).

## Version 2.0 (MacOS X 10.5.0)

- The basic infrastructure for playing nice in a GC host was added.

  This doesn’t mean that PyObjC now actually plays nice with the ObjC garbage collector, some more development and much more testing is needed for that.

  Even so, the end result is about as good as we have without GC, programs won’t make optimal use of GC because that would require surgery on the Python interpreter itself.

- The metadata returned by the `__metadata__` method is slightly changed to make it more compatible with the XML files.

- Some of the older metadata attributes, such as `isAlloc` and `doesDonateRef` were dropped. `isAlloc` isn’t needed for anything but a number of now hardcoded methods (`+alloc` and `+allocWithZone:`), `doesDonateRef` is available through the new metadata mechanism.

- Fix a memory leak in the code that creates the python representation for method lists.

- Speed up framework loading due to three changes:

  1. Don’t rescan the list of classes unless the framework actually defines new classes.

  2. The metadata loader now implemented in C.

  3. CF wrapper types (e.g. CGContextRef) no longer have methods corresponding to global functions, the speed-hit for calculating these is too large.

- It is now conveniently possible to create instance variables with a specific type (e.g. without manually making up a encoded type string):

      1 class MyObject (NSObject):
      2     bounds = objc.ivar.NSRect()
      3     done = objc.ivar.bool()

- Objective-C metaclasses are modelled as Python metaclasses. This brings a major improvement: class methods “just work”(TM):

      1o = NSObject.alloc().init()
      2o.description()
      3
      4NSObject.description()

  In earlier versions of PyObjC the second call would fail because `NSObject.description` referred to an unbound instance-method instead of to the class method.

  This change should require little or change to existing code. There’s only two types of code where the new behaviour is incompatible:

  1. Code that introspects the class dictionary to see what methods are available. These will no longer see class methods, but will have to look at the metaclass as well. This affects `pydoc(1)` as well.

  2. Code that uses unbound instance methods will no pick up class methods in some occasions. Use `MyClass.instanceMethodForSelector_` instead of unbound methods, or alternatively access instance methods through `MyClass.pyobjc_instanceMethods`.

  3. Due to a limitation in the implementation of python’s `super` class [1] it is not possible to use the super machinery to resolve class methods.

     However, `from Foundation import *` will replace the builtin `super` by a subclass that does work correctly for PyObjC programs, therefore this doesn’t affect most PyObjC-using programs.

[ 1 ]

It is not possible to override the way `super` looks for the “next” method to call. The class `objc.super` is a subclass of the builtin superclass with a `__getattr__` implementation that does the right thing for supercalls for Objective-C class methods.

- It is now easily possible to tell PyObjC that a Python type should be treated like a builtin sequence type:

      1   import UserList, objc
      2
      3   class MyClass (UserList.UserList):
      4       pass
      5
      6   objc.registerListType(MyClass)

- And likewise for mapping types using `objc.registerMappingType`.

- `objc.enableThreading()` is gone. It was introduced in ancient times to enable threading in the Python runtime but has been a no-op for ages because the PyObjC enables threading by default now.

- The unittests can now use the leaks(1) command to check for memory leaks. This slows testing down significantly and is therefore off by default. Enable by setting `PYOBJC_WITH_LEAKS` to a value in the shell environment before running the tests:

          $ PYOBJC_WITH_LEAKS=1 python setup.py test

      NOTE: the actual value is ignored, as long as there is a value.

- (BUGFIX): PyObjC was leaking memory when doing scans of the Objective-C method tables

- (BUGFIX): The code below now raises an error, as it should have done in previous versions but never did:

      1  class MyObject (object):
      2      def updateDescription(self):
      3          self.description = 42

- PyObjC has been split into several smaller packages: `pyobjc-core` contains the core bridge and frameworks are wrapped as seperate setuptools packages.

- Objective-C objects now have an implicit attribute named `_` which can be used a shortcut for Key-Value-Coding.

  The code fragment below:

      1   o = <Some Objective-C Object>
      2   print o._.myKey
      3   o._.myKey = 44

  is equivalent to:

      1   print o.valueForKey_('myKey')
      2   o.setValue_forKey_(44, 'myKey')

  The former is much nicer to use.

- Struct wrappers now have a `copy` method. This method tries to do the right thing when subfields are other struct wrappers (that is, deep-copy them).

- The metadata system has been revamped and mostly removes the need to write C-code when wrapping frameworks (that includes most of the AppKit and Foundation wrappers as well). The metadata is loaded at runtime from an XML file, whose format is shared between PyObjC and RubyCocoa.

  `objc.initFrameworkWrapper` can be used to load a framework using these XML metadata files.

  Note: because we now use an XML metadata file the scripts in `Scripts/CodeGenerators` have been removed: they are no longer needed. Have a look at the project `pyobjc-metadata` if you want to generate your own metadata.

  Note2: the metadata format is shared with RubyCocoa, although there are currently some slight differences (that is, the PyObjC metadata is slightly richer).

- PyObjC now has builtin support for CoreFoundation-based types, which is used by the new metadata file support. Note that doesn’t mean we support all of CoreFoundation and other CF-based frameworks, just that the machinery that’s needed for that is present and working.

  This is a backward incompatible change: CF-based types will now be proxied using PyObjC-owned types instead of the ones in MacPython. However, PyObjC will still convert MacPython CF-wrappers to the right native type.

  Another backward compatible change: `registerCFSignature` has a different signature:

      registerCFSignature(name, encoding, typeId [, tollfreeName]) -> type

  This is needed to capture all information about CF types.

- This version introduces generic support for callback functions. The metadata metioned before contains information about the signature for callback functions, the decorator `callbackFor` converts a plain function to one that can be used as a callback:

      1   @objc.callbackFor(NSArray.sortedArrayUsingFunction_andContext_)
      2   def compare(left, right, context):
      3       if left.key < right.key:
      4           return NSOrderedAscending
      5       elif left.key > right.key:
      6           return NSOrderedDescending
      7       else:
      8           return NSOrderedSame

  The `makeCallbackFor` callback should be used for callbacks where the callable is stored by the called function and is optional otherwise (such as the example above).

- The decorator `selectorFor` can be used to ensure that a method has the right signature to be used as the callback method for a specific method.

  Usage:

      @objc.selectorFor(NSApplication.beginSheet_modalForWindow_modalDelegate_didEndSelector_contextInfo_)
      def sheetDidEnd_returnCode_contextInfo_(self, sheet, returnCode, info):
          pass

- PyObjC compiled on Leopard uses the Objective-C 2.0 runtime.

  The compiler on 10.5 still gives warning about usage of deprecated APIs unless compiling for 10.5 or later because of a compatibility layer.

- GNUstep support has been removed because this has never worked properly, nobody seems interested in fixing that and the internal APIs of PyObjC have changed greatly.

- Output arguments are treated slightly different. In previous versions you were not allowed to pass values for output arguments.

  This is now deprecated behaviour, you should choose to suply values for all arguments including output arguments (mixing these two styles is not allowed, if you have two output argument you must either supply a value for both of them or neither).

  There are only two acceptable values for output argument:

  - `None`: pass a non-NULL pointer to the objc function/method

  - `objc.NULL`: pass a NULL pointer to the objc method.

  The already existing behaviour is the same as passing in `None` for all output arguments.

  This is most useful for supressing an `NSError` value for methods that have an `NSError**` argument (when you don’t want to look at that value), because generating that object might be expensive.

- `objc.setSignature` is deprecated, use the new metadata machinery instead.

- Opaque types (such as NSZonePointer) are now mutable, which is mostly present to allow framework wrappers to provide a nice OO interface to those types instead of forcing users to use the procedural API.

  None of the current framework wrappers use this feature.

- Several new methods were added to improve integration with a future version of MacPython: opaque pointer types and `NSObject` now have a method named `__cobject__` that returns a `PyCObject` which represents the proxied value. Furthermore both opaque pointer types and subclasses of `NSObject` are now callable and will create the proper proxy object when passed a `PyCObject`. Note however than the caller is responsible to ensure that the `PyCObject` value represents a value of the right type.

- Archiving pure python objects using `NSArchiver` was already unsupported, we now explicitly raise an exception when users try to do this anyway. It is supported to archive and retrieve simple values: instances of `int`, `long`, `float`, `str` and `unicode`.

- A `__del__` or `dealloc` method can revive objects, which isn’t really supported by Objective-C. We’ll now warn about this, hopefully before the program crashes. The warning is `objc.RevivedObjectiveCObjectWarning`.

- Some functions and methods return an instance of `objc.varlist`. These objects behave a little like tuples, but don’t have a defined lenght, you are responsible to not peak beyond the end of the actual array.

  The best way to deal with these objects is to convert them to real tuples as soon as possbible (using the `as_tuple` method). The number of elements in that tuple should be known to you and depends on the API.

  These objects are used in places where objects return an array but the size of that array cannot be described using the bridge metadata. These are mostly arrays whose size depends on the state of an object, or whose size is a function of one or more arguments of the method.

- There now is a public API for adding new “convenience methods”, that is methods that emulate standard Python methods using Objective-C methods.

  There are two functions for adding new convenience methods:

  - `addConvenienceForSelector` adds a list of methods to a class when that class has the specified selector:

      addConvenienceForSelector('hash', [
               ('__hash__', lambda self: self.hash()),
       ])

  - `addConvenienceForClass` adds a list of methods to the class with the

      specified name:

      addConvenienceForSelector('NSObject', [
               ('dummy', lambda self: 42 ),
       ])

  In both cases the addition is done lazily, the class that will be changed need not be loaded at the time of the call.

- Fix a long-standing race condition where one could end up with a reference to an already deallocated Objective-C object when the last ObjC reference goes away on one thread and is just “recreated” on a second thread.

- The ‘name’ and ‘reason’ of an Objective-C exception are now represented as Unicode objects in the Python representation of the exception, instead of as a UTF-8 encoded string.

  The standard Python exception message is still a UTF-8 encoded string, that’s needed to ensure that we can always print the value of the exception message (such as in tracebacks).

## Version 1.4.1 (2006)

- PyObjC now uses setuptools. Setuptools support is fairly minimal at the moment, we expect to move more of the build infrastructure to setuptools and to split PyObjC into smaller eggs.

- Fix an issue that made is possible to create weakref’s to subclasses of subclasses of Objective-C classes. This was unintentional behaviour, the weakref is to the proxy (see the news for 1.0b1 for more details).

- Add RoundTransparentWindow and DragItemAround examples in `Examples/AppKit`.

  Both are ports of Objective-C examples at ADC and were provided by ytrewq1.

- Fix issue where programs would crash with an badly aligned C-stack on some problems. This issue only affected Intel systems.

- Remove `OC_PythonObject.pythonifyStructTable`. This method of wrapping structs was untested and not used in the core distribution. Use `objc.createStructType` instead.

- Binaries build on 10.4 also work on 10.3. This means it is no longer necessary to build PyObjC on the lowest version of the OS that you want to run your binaries on. Doing this with python is somewhat of a black art, please test your applications on the lowest version of the OS that you want to support to make sure that this actually works.

## Version 1.4 (2006-06-14)

- Classes whose name starts with and underscore are no longer imported when using `objc.loadBundle`. They are still available using `objc.lookUpClass`.

  Methods whose name starts with an underscore are no longer visible when introspecting using `dir()`, but can still be called.

  These changes were done to make introspection slightly more user-friendly: anything that is now hidden from introspection is most likely not part of a public API.

- Most of the libffi testsuite is now run using a module that emulates dejagnu.

- Introduction of a GUI tool to manage custom method signatures (`Tools/Signatures`). This replaces the `find-raw-pointers.py` script.

- Fixed memory leak in `OC_PythonObject`, this was due to bad reference counting.

- `NSMutableArray.sort` now has the same API as `list.sort`. Due to implementation constraints the `key` argument results in slower sorting than you’d see with `list.sort`.

- Selectors now have a read-only property ‘native_signature’ that contains the untampered signature for the method. This is for use by tools.

- ‘void*’ arguments are treated like unsigned integers, they are almost always opaque cookies.

- `FILE*` arguments are recognized and mostly work correctly. We can’t reliably detect if the file was opened in append mode though.

- Make it possible to override the KVO methods, like `setValue:forKey:` and `valueForKey:` in Python for all levels in the inheritance hierarchie.

- Fix issues with reference counts for `__slots__`.

- Experimental: use `-autorelease` instead of `-release` to release values in destructors. This seems to solve at least one memory managment issue.

- A slight complication in the naming rule:

  1. Don’t translate leading underscores in Python to colons in Objective-C, `_doFoo_andBar_` in Python will be `_doFoo:andBar:` in Objective-C.

  2. If a name starts and ends with double underscores don’t modify the name at all when moving from Python to Objective-C, `__foobar__` in Python will stay that way in Objective-C.

  These changes fix some minor annoyances with the older scheme. Note that the translation from Objective-C to Python is unmodified and is entirely consistent with the modified rules for translating from Python to Objective-C.

- Fix for a memory leak in `__pyobjc_object__` handling.

## Version 1.3.7 (2005-07-06)

- Added wrappers for embedded DiscRecording frameworks ([ 1224188 ] Fix for DiscRecording framework)

- Probably working Xcode 2.1 support (for converted Xcode 2.0 projects)

- Hide List, Object, and Protocol classes from objc.loadBundle to prevent confusion with Python code. They can still be looked up with objc.lookUpClass.

- Fixed a regression where type signatures for pointers weren’t normalized (fixes uses of NSModalSession, etc.)

- Fixed a bug with -[NSObject hash] to __hash__, there was a mismatch between integer types.

- Removed traces of the old Project Builder and Xcode templates in the examples and Foundation initialization code (PYOBJCFRAMEWORKS).

- Fixed a problem with reference counting in initializers.

- New TinyURLService example in AppKit that demonstrates how to write a service that transforms URLs into their tinyurl.com equivalents.

- Ported to macOS on Intel. This is an initial, experimental port. The Intel ABI has not been finalised yet. It is also possible to build fat binaries, that option should not be used in production builds.

- Support a number of new frameworks:

  - SenTestingKit

    TODO: this framework uses lots of macros (such as STAssertEquals), these have not yet been wrapped/converted.

  - SecurityFoundation

## Version 1.3.6 (2005-05-19)

- Fixed bugs in the ProgressViewPalette example

- Fixed a bug in the class builder that caused most plugins to break

- Removed all references to Project Builder

- macOS 10.2 (Jaguar) no longer supported

## Version 1.3.5 (2005-05-18)

- Importing objc now ensures that Foundation is multi-threaded, previously it only ensured that Python was.

- New `objc.RegisterCFSignature` used to register `CFTypeRef`-like signatures with the runtime.

- `PyObjCTools.Conversion` functions now support all property list types with the following conversions:

  - NSData <-> buffer

  - NSDecimalNumber <-> decimal.Decimal (if present)

  - NSDate <-> datetime.datetime

  New `toPythonDecimal`, `fromPythonDecimal` functions which convert between NSDecimalNumber and decimal.Decimal using an intermediate string.

  New `serializePropertyList` and `deserializePropertyList` functions which serialize (Objective-C) property lists to and from NSData.

- `OC_PythonObject`, the proxy for Python objects that do not have an Objective-C superclass and are not otherwise special-cased, now act slightly more like typical Objective-C objects (supporting `-isEqual:`, `-hash`, and `-compare:`). This allows them to work with Key-Value Coding if they are contained by an Objective-C object, among other things.

- New objc.signature decorator that allows easier specification of objc.selector wrappers for functions when using Python 2.4:

      @objc.signature('i@:if')
      def methodWithX_andY_(self, x, y):
          return 0

- `PyObjCTools.KeyValueCoding.getKeyPath` now supports all of the Array Operators supported by macOS 10.4.

- Key-Value Coding of Python objects (whether or not using an Objective-C base class) should act like Objective-C now. In previous versions there were inconsistencies with the use of capitalization, the underscore postfix in setters, and Key-Value Observing.

- The formal protocol list is now complete. A new internal function, `objc.protocolsForProcess()` enumerates over all mach headers and returns all of the protocols defined in the expected place. This fixes the scenario where an application uses a protocol but does not define any classes that conform to that protocol (i.e. to check plugin conformity). Previously it was not possible to reach these protocols simply by walking over all of the classes.

- A special value, `objc.NULL`, may now be passed in the place of ‘in’ and ‘inout’ arguments. This tells the bridge to pass a NULL pointer to the Objective-C method, instead of a pointer to the value. The return value will still be a tuple of the expected size.

- Some of the new Tiger frameworks now have wrappers:

  - `AppleScriptKit`

  - `Automator`

  - `CoreData`

  - `DiscRecording`

  - `DiscRecordingUI`

  - `OSAKit`

  - `Quartz`

  - `QTKit`

  - `SyncServices`

  - `XgridFoundation`

  Documentation and tests not yet written.

- New `OutlineEditor` example in `Examples/CoreData`, it is a Python version of the identically named Apple example.

- The last argument of selectors that end with ‘:error:’ is now assumed to be ‘out’ if its type is an object pointer.

- More conveniences for `list`-like and `dict`-like objects: `__reversed__`, `reverse`, `pop`, `remove`, `fromkeys`.

- `OC_PythonDictionary` and `OC_PythonArray` now return `NSNull` to Objective-C callers as appropriate.

- New `WebKitInterpreter` example in `Examples/Plugins`. Uses the new WebKit Cocoa plugin API available in Safari 1.3 and later to embed a PyInterpreter in the browser.

- Fixed a `CFBundleRef` reference counting bug in `Foundation._Foundation`. The symptom of this is usually a crashing application after having loaded a PyObjC-based plugin into an otherwise Objective-C app.

- New `PyObjCTools.AppHelper` functions: `callAfter` and `callLater`, conveniences for calling Python functions on the main thread as soon as possible, or after a delay.

- Twisted examples changed to use `threadedselectreactor` instead of `cfreactor`. `cfreactor` is deprecated. Needs Twisted newer than 2.0 (svn r13575 or later).

- `objc.inject` now injects on main thread by default, and takes an optional third `useMainThread` argument to change this behavior. This is a complete rewrite which should be correct, stable, Tiger compatible, and synchronized with mach_* 1.1.

- Removed an `NSAutoreleasePool` category hack that has been deprecated for quite some time.

- New `objc.removeAutoreleasePool` function that will remove PyObjC’s global `NSAutoreleasePool`, which may be useful for plugins.

- Fixed bug in the `NSBundle` hack that caused a `NULL` pointer dereference if looking up a non-existent class using `NSBundle` API.

- Added `OC_PythonUnicode` and `OC_PythonString` classes that preserve the identity of `str` and `unicode` objects across the bridge. The bridge for `str` now uses the default encoding of `NSString`, rather than `sys.getdefaultencoding()` from Python. For macOS, this is typically MacRoman. The reason for this is that not all Python `str` instances could cross the bridge at all previously. `objc.setStrBridgeEnabled(False)` will still trigger warnings, if you are attempting to track down an encoding bug. However, the symptoms of the bug will be incorrectly encoded text, not an exception.

- New Xcode project template “PyObjC Mixed Application” that is a py2app based Python application that loads an Objective-C plug-in built as a separate target.

- New py2app based Xcode templates “PyObjC Application” and “PyObjC Document-based Application”, these replace the older “Cocoa-Python Application” and “Cocoa-Python Document-based Application” respectively.

- New `InjectBrowser` example in `Examples/Inject` that demonstrates injection of the `ClassBrowser` example into another application using `objc.inject`.

- `NSData` and `NSMutableData` instances now support the Python buffer protocol.

- `NSData` instances now support a convenience API that allow them to act like a `buffer` instance for `str()` and slicing.

- Objects that support the Python buffer protocol, such as `buffer` and `array.array` (but not `str` or `unicode`) are now bridged as `NSData` subclasses.

## Version 1.3 (2005-03-31)

- New `objc.pyobjc_id` function that returns a the id of the underlying NSObject as an integer. (Python wrapper objects are often made on the fly, meaning `id(obj)` is not constant during the lifetime of the object.)

- The bridge now maintains object identity across the bridge in both directions. Previous versions of the bridge only did this when bridging from Objective-C to Python.

  Exceptions: `NSString` and `NSNumber` do not have unique proxies. These types are converted to subclasses of Python types as appropriate, so they can not have unique proxies. The identity of the original Objective-C object is maintained by these subclasses, but there may be many Python “value proxies” for a single Objective-C object.

  Any Python object that is proxied using the `__pyobjc_object__` interface will only get a unique proxy if the `__pyobjc_object__` method implements that feature.

- New `objc.protocolsForClass` function that returns a list of protocols that the class directly claims to conform to.

- PyObjC classes can now declare that they implement formal protocols, for example:

      class MyLockingClass(NSObject, objc.protocolNamed('NSLocking')):
          # implementation
          pass

  It is also possible to define new protocols:

      MyProtocol = objc.formal_protocol("MyProtocol", None, [
       selector(None, selector='mymethod', signature='v@:'),
      ])

  All formal protocols are instances of `objc.formal_protocol`.

- PyObjCTools.KeyValueCoding has a new `kvc` class that allows Pythonic Key-Value Coding.

  - `__getitem__` is mapped to `valueForKeyPath:`

  - `__setitem__` is mapped to `setValue:forKeyPath:`

  - `__getattr__` is mapped to `valueForKey:`

  - `__setattr__` is mapped to `setValue:forKey:`

  The `kvc` class uses `__pyobjc_object__`, so it may cross the bridge as the wrapped object.

- `NSNumber` instances are bridged to a `float`, `long`, or `int` subclass that uses `__pyobjc_object__`. `NSDecimal` is converted to `NSDecimalNumber` when used as an object, `NSDecimalNumber` is not bridged to `NSDecimal` because the latter is a mutable type.

- The Python to Objective-C bridge now looks for a `__pyobjc_object__` attribute to get a PyObjC object from a Python object.

- New IDNSnitch example in Inject that demonstrates how to write an monitor for the launch of another application, use `objc.inject` to load code into a target process, and override the implementation of an existing method but still call back into the original implementation (method swizzling).

- `objc.IMP` should do the right thing now. This type is returned by `+[NSObject methodForSelector:]` and `+[NSObject instanceMethodForSelector:]`

- New ToDos example in CocoaBindings that demonstrates how to use two array controllers for the same data, and how to use value transformers to alter the color of text. Originally from “Cocoa Bindings Examples and Hints”, converted to PyObjC by u.fiedler.

- New Bookmarks example in CocoaBindings that demonstrates how to subclass `NSArrayController` to implement the `NSTableView` delegate drag and drop protocol, including copying of objects between documents and accepting URL drops from other applications. Also demonstrates re-ordering of the content array. Originally from “Cocoa Bindings Examples and Hints”, converted to PyObjC by u.fiedler.

- New FilteringController example in CocoaBindings that demonstrates how to subclass `NSArrayController` to implement filtering of a `NSTableView`. Also demonstrates the use of indexed accessors. Originally from “Cocoa Bindings Examples and Hints”, converted to PyObjC by u.fiedler.

- New ControlledPreferences example in CocoaBindings that demonstrates how to use Cocoa Bindings to simplify storing and retrieving user preferences. Originally from “Cocoa Bindings Examples and Hints”, converted to PyObjC by u.fiedler.

- New TemperatureTransformer example in CocoaBindings that demonstrates how to use NSValueTransfomers with PyObjC. Based on Apple’s “Cocoa: Value Transformers” documentation, converted to PyObjC by u.fiedler.

- New CurrencyConvBindings example in CocoaBindings that demonstrates a Cocoa Bindings enabled version of the CurrencyConverter example. Converted to PyObjC by u.fiedler from the example in Apple’s “Introduction to Developing Cocoa Applications Using Bindings”.

- New ManualBindings example in CocoaBindings that demonstrates how to develop programmatic bindings from a PyObjC application. Converted to PyObjC by u.fiedler from the “Cocoa Bindings and Hints” example of the same name.

- New HotKeyPython example in AppKit that demonstrates how to use Carbon global hot keys from a PyObjC application. Also demonstrates how to use a NSApplication subclass.

- Key-Value Observing support is now automatic in Python classes that descend from `NSObject`, unless they implement a custom `willChangeValueForKey:`, `didChangeValueForKey:`, or `__useKVO__` is not True. This allows `self.foo = 1` to automatically trigger notifications. This works in all cases, whether `foo` is a `property`, `ivar`, or just in the `__dict__`.

- New Inject folder in Examples, with an InjectInterpreter example that will inject a GUI Python interpreter into any process.

- New `objc.inject()` function for macOS 10.3 and later, allows an arbitrary bundle to be loaded into another process using mach_inject.

- `objc.classAddMethods` now recognizes and supports classmethods.

- GC is now correctly implemented for struct wrappers.

- The `NSNumber` bridge has been removed, now you will get `NSNumber` instances across the bridge instead of a Python representation.

- `PyObjCTools.AppHelper.runEventLoop()` will now bring your application to the front at startup when using pdb mode for convenience.

- `objc.loadBundle()` no longer filters the class list. This solves a few potential issues and shaves off about 1/3rd of the overhead of `python -c "import AppKit"`.

- `PyObjCTools.AppHelper.runEventLoop()` no longer breaks on pure Objective-C exceptions. Most exceptions of this variety are more like warnings, and there is nothing that can be done them anyway.

- `PyObjCTools.AppHelper.runEventLoop()` now installs the interrupt handler and verbose exception logging when using pdb, either explicitly or by the USE_PDB environment variable.

- There is now a fast path for the `NSString`/`unicode` bridge when `Py_UNICODE_SIZE` is 2. This is the default setting for Python.

- The default selector signature will have a void return value unless a “return” statement with an argument is used in the bytecode. In that case, it will default to an object return value.

- `__bundle_hack__` is no longer necessary, py2app now sets a different environment variable to the current plugin during execution, and a hack is installed to `NSBundle` so that classes may respond to requests for their bundle with the `+bundleForClass` method. The class builder adds a default implementation of this to Python classes if this environment variable is set.

- Added `objc.currentBundle()`, which is equivalent to `NSBundle.mainBundle()` except after loading a plug-in. Makes it easier to load nib files.

- `PyObjCTools.NibClassBuilder.extractClasses()` now uses `objc.currentBundle()` instead of `NSBundle.mainBundle()`. This makes plugins less of a hassle to develop and allows identical code to be used for application or plugin development.

- `objc.registerPlugin()` and `objc.pluginBundle()` are now deprecated as they are no longer useful.

- It is now possible to subclass a class that implements `copyWithZone:` without setting `__slots__` to `()`.

- It is now possible to override `dealloc`. It is still possible to define `__del__`.

- As an experimental feature it is also possible to override `retain` and `release`. Note it almost never a good idea to do this (even when you’re programming in Objective-C and much more so in Python).

- `poseAsClass:` can be used, although it is not very useful in python, use categories instead.

  A major issue with `poseAsClass:` is that existing references to the old version of the class won’t be changed to point to the new class.

- It is now possible to access all instance variables of a class using the functions `objc.listInstanceVariables(aClassOrInstance)`, `objc.getInstanceVariable(obj, name)` and `objc.setInstanceVariable(obj, name, value [, updateRefCount])`.

  The last argument of `setInstanceVariable` is required when the instance variable is an object. If it is true the bridge will update reference counts, otherwise it won’t.

- All wrappers for opaque pointers (such as `NSZone*`) now have the same interface and share a single implementation. This decreases code-size and makes it easier to add new wrappers. A new feature is a `__typestr__` attribute on the type object, this contains the encoded Objective-C type of the pointer.

  A function for creating new wrappers is exposed to python, as `objc.createOpaquePointerType(name, typestr, doc)`. The same function is also exposed in the C-API.

- Wrappers for C-structs how have a `__typestr__` attribute on their type. This attribute contains the encoded Objective-C type of the struct.

  The default `__init__` for struct-wrappers now initializes fields with an appropriate default value, instead of `None`.

  New wrappers can now be created from Python using the function `objc.createStructType(name, typestr, fieldnames, doc)`. The same function is also exposed in the C API (and has been for a while).

## Version 1.2 (2004-12-29)

- `PyObjCTools.AppHelper.stopEventLoop` will attempt to stop the current `NSRunLoop` (if started by `runConsoleEventLoop`) or terminate the current `NSApplication` (which may or may not have been started by `runEventLoop`).

- This version no longer support Python 2.2. Python 2.3 or later is required.

- It is now possible to use `reload` on modules containing Objective-C classes.

- `objc.loadBundle` now returns bundle we just loaded.

- Added `objc.loadBundleVariables` and `objc.loadBundleFunctions`, two functions for reading global variables and functions from a bundle.

- objc.runtime will now raise AttributeError instead of objc.nosuchclass_error when a class is not found.

- objc.Category can be used to define categories on existing classes:

      class NSObject (objc.Category(NSObject)):
          def myMethod(self):
              pass

  This adds method `myMethod` to class NSObject.

- `py2app` is now used for all Example scripts and is the recommended method for creating PyObjC applications.

- Proxies of dict, list, and tuple now respect the invariant that you should get an identical instance if you ask for the same thing twice and the collection has not been mutated. This fixes some problems with binary plist serialization, and potentially some edge cases elsewhere.

- There is now a `__bundle_hack__` class attribute that will cause the PyObjC class builder to use a statically allocated class wrapper if one is available via certain environment variables. This functionality is used to enable +[NSBundle bundleForClass:] to work for exactly one class from a py2app-created plugin bundle.

- We now have a working Interface Builder palette example due to `__bundle__hack__`.

- `bool(NSNull.null())` is now false.

- `setup.py` supports several new commands:

  > build_libffi:

  > > builds libffi (used by build_ext)

  > build_html:

  >   builds html documentation from ReST source

  > bdist_dmg:

  >   creates a disk image with the binary installer

  > bdist_mpkg:

  >   creates a binary installer

  > test:

  >   runs unit test suite (replaces Scripts/runPyObjCTests and Scripts/runalltests)

- `PyObjCStrBridgeWarning` can now be generated when Python `str` objects cross the bridge by calling `objc.setStrBridgeEnabled(False)`. It is HIGHLY recommended that your application never send `str` objects over the bridge, as it is likely to cause problems due to the required coercion to unicode.

- The coercion bridge from Python to Objective-C instances can now be augmented from Python as it is exposed by `OC_PythonObject`. See `objc._bridges`. This is how the `str` -> `unicode` -> `NSString` bridge with optional warnings is implemented.

- The coercion bridge between Python objects and Objective-C structures can now be augmented from Python as it is exposed by `OC_PythonObject`. See `objc._bridges`. This is how the `Carbon.File.FSRef` <-> `'{FSRef=[80c]}'` structure bridge is implemented.

- Extension modules such as `_objc`, `_AppKit`, etc. are now inside packages as `objc._objc`, `AppKit._AppKit`, etc. They should never be used directly, so this should not break user code.

## Version 1.1 (2004-05-30)

- KVO now actually works from Python without using nasty hacks.

- Added Xcode template for document-based applications

## Version 1.1b2 (2004-04-11)

- More fine-grained multi-threading support

- Xcode templates use a smarter embedded main program

- Add support for WebObjects 4.5 (a one-line patch!)

- Add a PackageManager clone to the Examples directory

- Add better support for NSProxy

  This makes it possible to use at Distributed Objects, although this feature has not received much testing

- Function ‘objc.protocolNamed’ is the Python equivalent of the @protocol expression in Objective-C.

- Add several new examples

## Version 1.1b1 (2004-02-20)

- Fixes some regressions in 1.1 w.r.t. 1.0

- Add Xcode templates for python files

  You can now select a new python file in the ‘add file…’ dialog in Xcode

- Fix installer for Panther: the 1.1a0 version didn’t behave correctly

- There is now an easier way to define methods that conform to the expectations of Cocoa bindings:

      class MyClass (NSObject):

         @objc.accessor
         def setSomething_(self, value):
             pass

         @objc.accessor
         def something(self):
             return "something!"

  It is not necessary to use `objc.accessor` when overriding an existing accessor method.

## Version 1.1a0 (2004-02-02)

- Objective-C structs can now be wrapped using struct-like types. This has been used to implement wrapper types for NSPoint, NSSize, NSRange and NSRect in Foundation and NSAffineTransformStruct in AppKit.

  This means you can now access the x-coordinate of a point as `aPoint.x`, accessing `aPoint[0]` is still supported for compatibility with older versions of PyObjC.

  It is still allowed to use tuples, or other sequences, to represent Objective-C structs.

  NOTE: This has two side-effects that may require changes in your programs: the values of the types mentioned above are no longer immutable and cannot be used as keys in dicts or elements in sets. Another side-effect is that a pickle containing these values created using this version of PyObjC cannot be unpickled on older versions of PyObjC.

- This version adds support for NSDecimal. This is a fixed-point type defined in Cocoa.

- NSDecimalNumbers are no longer converted to floats, that would loose information.

- If an Objective-C method name is a Python keyword you can now access it by appending two underscores to its name, e.g. someObject.class__().

  The same is true for defining methods, if you define a method `raise__` in a subclass of NSObject it will registered with the runtime as `raise`.

  NOTE: Currently only `class` and `raise` are treated like this, because those are the only Python keywords that are actually used as Objective-C method names.

- Experimental support for `instanceMethodForSelector:` and `methodForSelector:`. This support is not 100% stable, and might change in the future.

- Backward incompatible change: class methods are no longer callable through the instances.

- Integrates full support for MacOS X 10.3 (aka Panther)

- Adds a convenience/wrapper module for SecurityInterface

- It is now safe to call from Objective-C to Python in arbitrary threads, but only when using Python 2.3 or later.

- Fixes some issues with passing structs between Python and Objective-C.

- Uses the Panther version of `NSKeyValueCoding`, the Jaguar version is still supported.

- method `updateNSString` of `objc.pyobjc_unicode` is deprecated, use create a new unicode object using `unicode(mutableStringInstance)` instead.

- NSAppleEventDescriptor bridged to Carbon.AE

- LibFFI is used more aggressivly, this should have no user-visible effects other than fixing a bug related to key-value observing.

- Adds a number of new Examples:

  - OpenGLDemo

    Shows how to use OpenGL with PyObjC

  - SillyBallsSaver

    Shows how to write a screensaver in Python. Requires a framework install of Python (that is, MacOS X 10.3 or MacPython 2.3 on MacOS X 10.2).

  - Twisted/WebServicesTool

    Shows how to integrate Twisted (1.1 or later) with Cocoa, it is a refactor of the WebServicesTool example that is made much simpler by using Twisted.

  - Twisted/WebServicesTool-ControllerLayer

    Shows how to integrate Twisted (1.1 or later) with Cocoa, it is a refactor of the WebServicesTool example that is made much simpler by using Twisted as it does not need threads. This one also uses NSController and therefore requires MacOS X 10.3.

## Version 1.0 (2003-09-21)

- This version includes a new version of libffi that properly deals with complex types on MacOS X.

## Version 1.0rc3 (2003-09-14)

- 1.0rc2 didn’t include the nibclassbuilder script

- Fix bug in NSRectFillList

## Version 1.0rc2 (2003-09-10)

- Fix a number of bugs found in 1.0rc1.

## Version 1.0rc1 (2003-08-10)

- Better support for the NSKeyValueCoding protocol. The module `PyObjCTools.KeyValueCoding` provides a python interface that makes it possible to use key-value coding with python objects as well as Objective-C objects. Key-Value Coding also works as one would expect with Python objects when accessing them from Objective-C (both for plain Python objects and Python/Objective-C hybrid objects).

- objc.pyobjc_unicode objects are now pickled as unicode objects, previously the couldn’t be pickled or were pickled as incomplete objects (protocol version 2).

- Pickling of ObjC objects never worked, we now explicitly throw an exception if you try to pickle one: pickle protocol version 2 silently wrote the incomplete state of objects to the pickle.

- The default repr() of ObjC objects is now the result of a call to the `description` method. This method is not called for unitialized objects, because that might crash the interpreter; we use a default implementation in that case.

- A minor change to the conversion rule for methods with output arguments (pointers to values in ObjC, where the method will write through the pointer). If the method has ‘void’ as its return type, we used to return a tuple where the first value is always None. This first element is no longer included, furthermore if the method has only 1 output argument we no longer return a tuple but return the output value directly (again only if the method has ‘void’ as its return type).

  This is a backward incompatible change, but there are not many of such methods.

- Another backward incompatible change is a minor cleanup of the names in the `objc` module. The most significant of these is the change from `recycle_autorelease_pool` to `recycleAutoreleasePool`. The other changed names are internal to the bridge and should not be used in other code.

- The interface of Foundation.NSFillRects changed, it now has an interface that is consistent with the rest of the bridge.

## Version 1.0b1 (2003-07-05)

- More tutorials

  Two new tutorials were added: ‘Adding Python code to an existing ObjC application’ and ‘Understanding existing PyObjC examples’. The former explains how you can use Python to add new functionality to an already existing Objective-C application, the latter explains how to understand PyObjC programs written by other people.

- More examples

  Three examples were added: DotView, ClassBrowser and PythonBrowser, respectively showing the use of a custom NSView, NSBrowser and NSOutlineView. PythonBrowser is reusable, making it trivial to add an object browser to your application.

- Support for MacOS X 10.1

  It is now possible to build PyObjC on MacOS X 10.1, with full access to the Cocoa API’s on that platform.

  Note: The port to MacOS X 10.1 is not as well supported as the 10.2 port. The developers do not have full-time access to a MacOS X 10.1 system.

- Support for the WebKit framework, included with Safari 1.0.

  If you build PyObjC from source you will have to build on a system that has the WebKit SDK installed to make use of this. Note that the additional functionality will only be usuable on systems that have Safari 1.0 installed, however as long as you don’t use the additional functionality it is safe to run a ‘WebKit-enabled’ PyObjC on systems without Safari 1.0.

- It is no longer necessary to specify which protocols are implemented by

  a class, this information is automaticly deduced from the list of implemented methods. You’ll still a runtime error if you implement some methods of a protocol and one of the unimplemented methods is required.

- Support for “toll-free bridging” of Carbon.CF types to Objective-C objects.

  It is now possible to use instances of Carbon.CF types in places where Objective-C objects are expected. And to explicitly convert between the two.

  Note: this requires Python 2.3.

- Better integration with MacPython 2.3:

  - `NSMovie.initWithMovie_` and `NSMovie.QTMovie` now use `QT.Movie` objects instead of generic pointer wrappers.

  - `NSWindow.initWithWindowRef_` and `Window.windowRef` now use `Carbon.Window` objects instead of generic pointer wrappers.

  - Methods returning CoreFoundation objects will return MacPython objects, and likewise, methods with CoreFoundation arguments will accept MacPython objects.

- It is now possible to write plugin bundles, such as preference panes for use in System Preferences, in Python. See Examples/PrefPanes for an example of this feature.

- The methods `pyobjcPopPool` and `pyobjcPushPool` of `NSAutoreleasePool` are deprecated. These were introduced when PyObjC did not yet support the usual method for creating autorelease pools and are no longer necessary.

- Improved unittests, greatly increasing the confidence in the correctness of the bridge.

- All suppport for non-FFI builds has been removed.

- Object state is completely stored in the Objective-C object. This has no user-visible effects, but makes the implementation a lot easier to comprehend and maintain.

- As part of the previous item we also fixed a bug that allowed addition of attributes to Objective-C objects. This was never the intention and had very odd semantics. Pure Objective-C objects not longer have a __dict__.

- Weakrefs are no longer used in the implementation of the bridge. Because the weakrefs to proxy objects isn’t very useful the entire feature has been removed: It is no longer possible to create weakrefs to Objective-C objects.

  NOTE: You could create weakrefs in previous versions, but those would expire as soon as the last reference from Python died, not when the Objective-C object died, therefore code that uses weakrefs to Objective-C objects is almost certainly incorrect.

- Added support for custom conversion for pointer types. The end result is that we support more Cocoa APIs without special mappings.

- The generator scripts are automaticly called when building PyObjC. This should make it easier to support multiple versions of MacOS X.

## Version 0.9 (May-02-2003)

- This version includes numerous bugfixes and improvements.

- The module AppKit.NibClassBuilder has been moved to the package PyObjCTools.

- Usage of libFFI (https://sourceware.org/libffi/) is now mandatory. The setup.py gives the impression that it isn’t, but we do not support non-FFI builds.

- We actually have some documentation, more will be added in future releases.

- There are more Project Builder templates (see ‘Project Templates’).

- The InterfaceBuilder, PreferencePanes and ScreenSaver frameworks have been wrapped.

- Management of reference counts is now completely automatic, it is no longer necessary to manually compensate for the higher reference count of objects returned by the alloc, copy and copyWithZone: class methods.

- Various function and keyword arguments have been renamed for a better integration with Cocoa. A partial list is of the changed names is:

      objc.lookup_class -> objc.lookUpClass
      objc.selector arguments/attributes:
          is_initializer -> isInitializer
          is_allocator -> isAlloc
          donates_ref -> doesDonateReference
          is_required -> isRequired
          class_method -> isClassMethod
          defining_class -> definingClass
          returns_self -> returnsSelf
          argument_types -> argumentTypes
          return_type -> returnType
      objc.get_class_list -> objc.getClassList

- On Python 2.2, objc.YES and objc.NO are instances of a private boolean type, on Python 2.3 these are instances of the builtin type bool.

- Because we now use libFFI a large amount of code could be disabled. The binaries are therefore much smaller, while we can now forward messages with arbitrary signatures (not limited to those we thought of while generating the static proxies that were used in 0.8)

- Better support for APIs that use byte arrays are arguments or return values. Specifically, the developer can now manipulate bitmaps directly via the NSBitmapImageRep class, work with binary data through the NSData class, and very quickly draw points and rects via NSRectFillList()

- We added a subclass of unicode that is used to proxy NSString values. This makes it easily possible to use NSString values with Python APIs, while at the same time allowing access to the full power of NSString.

## Version 0.8 (Dec-10-2002)

- GNUStep support has been removed for lack of support. Volunteers needed.

- Subclassing Objective-C classes from Python, including the addition of instance variables (like ‘IBOutlet’s)

- Generic support for pass-by-reference arguments

- More complete Cocoa package, including wrappers for a number of C functions, enumerated types, and globals.

- More example code

- Objective-C mappings and sequences can be accessed using the normal python methods for accessing mappings and sequences (e.g. subscripting works as expected)

- Documentation: See the directory ‘docs’

- Can build standalone Cocoa applications based entirely on Python without requiring that user installs anything extra (requires 10.2).

- Better packaging and wrapper construction tools (borrowed from MacPython).

- An installer package.

- Support for Project Builder based Cocoa-Python projects.

- Unit tests.

## Version 2002-01-30 (January 30, 2002)

- Version bumped to 0.6.1 ( __version__ is now a PyString )

- Will now build for Python 2.2

- added Cocoa package with Foundation.py and AppKit.py wrappers.

- HelloWorld.py in Examples

- builds with -g flag for debugging. -v option will dump log of message sends to /tmp file.

- Fixed one major runtime bug: added ISCLASS test before isKindOfClass - without check, it crashes on sends to abstract classes like NSProxy.

- There are still problems with Delegates and Notifications.

## Version 2001-03-17 (March 17, 2001)

- moved to using distutils setup.py (requires small patch to distutils that has been submitted against python 2.1b1)

## Version 2000-11-14 (November 14, 2000)

- GNU_RUNTIME is likely completely broken

- Compiles on macOS Server (python 2.0)

- Compiles on macOS (python 2.0)

- Works as either a dynamically loadable module or statically built into a python executable

- Requires a modified makesetup to work [patches have been sent to SourceForge.net’s Python project].

- Supports NSAutoReleasepool.

- Some pre-OSX stuff removed; references to old APIs, etc… (but nowhere near clean)

## Version 0.55, 18 August 1998

- Here again, supporting GNU_RUNTIME and GNUstep Base! On my new Linux box I can finally test the module against them: I installed the latest snapshot of gstep-core, that contains the base library too. Given a sane GNUstep env (GNUSTEP_XXX env vars), you should be able to build a static ObjC-ized interpreter by:

      o Adjusting Setup, commenting out NeXT definition and enabling GNU
        ones;
      o make -f Makefile.pre.in boot
      o make static

## Version 0.54, 24 March 1998

- OC_Pasteboard.[hm], OC_Stream.[mh] and ObjCStreams.m are definitively gone.

- OC_PythonObject derives from NSProxy.

## Version 0.53, 4 January 1998

- Tons of changes, retargeting the core functionality around the OpenSTEP API. This release basically matches the previous one in terms of functionalities, but is should be closer to GNUstep.

- OC_Streams and OC_Pasteboard aren’t supported, I’ve not yet decided if they are needed anymore.

- Updated LittleButtonedWindow demo.

## Version 0.47, 29 October 1996

- Misc/Makefile.pre.in automatically sets TARGET to `pyobjc`.

- ObjC.m splitted to ObjCObject.m ObjCMethod.m ObjCPointer.m ObjCRuntime.m.

- New (almost invisible) types: ObjCSequenceObject and ObjCMappingObject; this to implement sequence and mapping syntax (several mapping methods have stub implementation).

- OC_Pasteboard class is gone. Its functionalities are now in a category of Pasteboard/NSPasteboard.

- Better methods doc.

- PyArg_ParseTuple format strings contain arguments names.

- OC_Streams are mapped to ObjCStreams by pythonify_c_value and its counterpart.

## Version 0.46, 18 October 1996

- OC_Stream is now a subclass of NSData under Foundation.

- New Objective-C class: OC_Pasteboard. Use it instead of Pasteboard/ NSPasteboard.

- New Objective-C class: OC_PythonBundle. Use it instead of NXBundle/NSBundle. The ShellText demo has been upgraded to use it, and now you can run it directly from the WorkSpace.

- OC_Python.[hm] aren’t in the package anymore.

- Setup.in directives changed again, due to OC_Python.m dropping.

## Version 0.45, 14 October 1996

- Double syntax: to make it easier for us to test and choose the better candidate, the only one that will be present in the final 1.0 release. Keeping both would result in a speed penality.

- Revisited streams, in particular GNUstep support.

## Version 0.44, 9 October 1996

- Integers are now accepted too where floats or doubles are expected.

- New method: ObjC.make_pointer (1) returns an ObjCPointer containing `((void *) 1)`.

## Version 0.43, 7 October 1996

- Completed ObjCStream implementation. There is now a new module, ObjCStreams which is automatically loaded by ObjC. You can access it as ObjC.streams.

- Manual splitted in three parts: libPyObjC.tex with the chapter intro, libObjC.tex describing the main module, libObjCStreams.tex explains the stream facilities.

## Version 0.42, 4 October 1996

- You can pass initialization arguments when using the `Class()` syntax. You select the right initializer selector with the `init` keyword parameter.

- First cut on ObjCStream objects. Thanx to Bill Bumgarner for motivations.

- New demo ShellText, to test above points.

## Version 0.41, 2 October 1996

- Revised error messages: for arguments type mismatch they show the ObjC type expected.

- When a method returns a pointer to something, it gets translated as an ObjCPointer object, not the pythonified pointed value. When a method expects a pointer argument, it accepts such an object as well.

- New demo: Fred. To halt it, suspend the Python process with ^Z then kill it ;-).

- Setup.in directives changed. See the new file Modules/Setup.PyObjC.in

- Distribuited as a standalone package. Special thanks to Bill Bumgarner.

## Version 0.4, 27 September 1996

- Now handles methods returning doubles or floats.

- ObjCRuntime responds to .sel_is_mapped().

## Version 0.31, 26 September 1996

- It’s now possible to use a different strategy to map ObjC method names to Python ones. Sooner or later we should decide the one to go, and drop the other. For details, see comments on PYTHONIFY_WITH_DOUBLE_UNDERSCORE in objc_support.h.

- Manual section.

- ObjC.runtime.__dict__ added.

- ObjC.runtime.kind added.

## Version 0.3, 20 September 1996

- No user visible changes, just a little effort towards GNU_RUNTIME support.

## Version 0.2, 16 September 1996

- Accepts a struct.pack() string for pointer arguments, but…

- … New methods on ObjCMethod: .pack_argument and .unpack_argument: these should be used whenever an ObjC method expects a passed-by-reference argument; for example, on NeXTSTEP [View getFrame:] expects a pointer to an NXRect structure, that it will fill with the current frame of the view: in this case you should use something similar to:

      framep = aView.getFrame__.pack_argument (0)
      aView.getFrame__ (framep)
      frame = aView.getFrame__.unpack_argument (0, framep)

## Version 0.1, 13 September 1996

- Correctly handle pointer arguments.

- New syntax to get a class: ObjC.runtime.NameOfClass

- New syntax aliasing .new(): SomeClass()

- New Demo: LittleButtonedWindow, that tests points above.

- What follow is the recipe to get PyObjC dynamically loadable on NeXTSTEP:

  - apply the patch in Misc/INSTALL.PyObjC to Python/importdl.c

  - modify Python/Makefile adding the switch `-ObjC` to the importdl.o build rule:

        importdl.o:   importdl.c
          $(CC) -ObjC -c $(CFLAGS) -I$(DLINCLDIR) $(srcdir)/importdl.c

  - modify Modules/Setup moving the PyObjC entry suggested above AFTER `*shared*`, and remove `-u libNeXT_s -lNeXT_s` from it.

  - run `make`: this will update various files, in particular Modules/Makefile.

  - modify Modules/Makefile adding `-u libNeXT_s -lNeXT_s` to SYSLIBS:

        SYSLIBS=      $(LIBM) $(LIBC) -u libNeXT_s -lNeXT_s

  - run `make` again