Re: [Pyobjc-dev] Protocol support

[Bob I. <bo...@re...>]

On Feb 17, 2005, at 3:59 PM, Ronald Oussoren wrote:

>
> On 17-feb-05, at 4:47, Bob Ippolito wrote:
>
>> I've committed basic (formal) Protocol support.  It can be used just 
>> like informal protocols:
>>
>> import objc
>> from Foundation import *
>> NSLocking = objc.protocolNamed('NSLocking')
>> class Foo(NSObject, NSLocking):
>>     pass
>>
>> # I can't wait until this is FINALLY FIXED, it is the thing that 
>> annoys me most about PyObjC
>> >>> Foo.pyobjc_classMethods.conformsToProtocol_(NSLocking)
>> 1
>> >>> Foo.alloc().init().conformsToProtocol_(NSLocking)
>> 1
>>
>> It could use (at least) the following improvements:
>> - Protocols are not type checked.  Anything in the base list that is 
>> a PyObjCObject will get chunked into the protocol list.  Will 
>> probably crash if you do something really stupid (though there's 
>> plenty of that in PyObjC anyway)
> Protocols are now typechecked.
>
> I've also added some unittests for this feature.
>
>> - Protocols can not be created from PyObjC
>> - selectors don't benefit from the Protocol information like they do 
>> for informal protocols
>> - PyObjC doesn't verify that you implement the protocol like it does 
>> for informal protocols
>> - objc.protocolNamed is probably pretty slow, should use a lookup hash
> These still need to be implemented.

I just added an objc.protocolsForClass, and re-implemented 
protocolNamed in Python using a lookup hash but with the same search 
algorithm.  Could be faster if it cached classes it has seen, but I 
guess maybe a category could change the behavior of that so this is 
safer.

The other three more important things are still unimplemented :)

-bob