On Mar 25, 2011, at 7:09 PM, Toon Verwaest wrote:
>
>>> What do you think?
>>
>> I am for... for the JIT is is a monomorphic send to a primitive, so the IC
>> will be very effective
>> and should take care that the lookup is actually almost never done. (and the
>> lookup is the
>> only thing the #class bytecode saves, as the target method is a primitive).
> I think that programmers should have the illusion that the VM interacts with
> the system through message sends. By being able to overwrite this particular
> message you break this illusion.
Why that? I think exactly the opposite is true.
If I write
self class
I think that I send #class to self. But in the current system I do not.
If #class is not send, one can never ever do proxies that work for real. A
proxy can never stand in for an object as #class always answers "Proxy", even
though
it should not. Or for a Future it will say "Future".
> The VM will just fetch the real class; but the user doesn't get access to it
> anymore. Telling the system that this particular message shouldn't be
> overwritten is probably a good thing.
>
One should take care, but a system that just does not allow things like this
*even if you take care* is bad.
> If you want to overwrite the method class, maybe your tools should send
> another message than class in the first place?
>
So what if it's not a tool? It might be domain code that really does
self class == something
as part of execution. Now I want ot use a proxy here, but I can not.
Marcus
--
Marcus Denker -- http://www.marcusdenker.de
INRIA Lille -- Nord Europe. Team RMoD.
