2009/4/10 Philippe Marschall <philippe.marschall at gmail.com>:
> 2009/4/10 Igor Stasenko <siguctua at gmail.com>:
>> 2009/4/10 Philippe Marschall <philippe.marschall at gmail.com>:
>>> 2009/4/10 Ralph Johnson <johnson at cs.uiuc.edu>:
>>>>> A very interesting article that anyone interested in the topic must
>>>>> read: "What To Know Before Debating Type Systems"
>>>>> http://www.pphsg.org/cdsmith/types.html
>>>>
>>>> i disagree that "strong typing" doesn't mean anything.  Weak typing
>>>> means "has a type system but it is easy to get around it".  Strong
>>>> typing means "has a type system and you can't get around it easily".
>>>> Strong typing certainly does NOT mean compile-time typing.
>>>>
>>>> I agree that "dynamic" (checked at run-time) vs. "static" (checked at
>>>> compile-time) is what is important.  C and Fortran have weak static
>>>> type systems.  Java has a strong static type system, but only because
>>>> casts are checked at run-time, i.e. the static type system has holes
>>>> in it but the run-time system patches those holes.  Smalltalk has a
>>>> strong dynamic type system; there is no way to run a method on an
>>>> object that it doesn't belong to.
>>>
>>> #valueWithReceiver:arguments:?
>>>
>> Right. But. Is given method is part of standard?
>
> What does that change?
>
>> IMO this is a dirty hack, which could crash the VM, if primitive
>> doesn't checking receiver & method class compatibility.
>
> Sounds pretty much like weak typing to me.
>
>> A secure VM could reject implementing primitive at all, and then as a
>> workaround, all you can do is temporarily compile&install given method
>> in receiver's class and only then send a message.
>
> Right and a multithreaded VM could, ... and an optimizing JIT could ...
>
Let's not mix a VM side and language side altogether. If you bury deep
into VM, you will find that there a very small number of primitives
checking which don't have any type checks.
>From your POV, then it would be right to say, that smalltalk is weakly
typed language, because its VM implemented in C.

> Cheers
> Philippe
>
>



-- 
Best regards,
Igor Stasenko AKA sig.