dynamic classes and duck typing

[Andrei Alexandrescu]

retard wrote:
> Tue, 01 Dec 2009 14:30:43 +0300, Denis Koroskin wrote:
> 
>> On Tue, 01 Dec 2009 14:26:04 +0300, retard <re at tard.com.invalid> wrote:
>>
>>> Tue, 01 Dec 2009 03:16:47 -0800, Walter Bright wrote:
>>>
>>>> Ary Borenszweig wrote:
>>>>> Can you show examples of points 2, 3 and 4?
>>>> Have opDispatch look up the string in an associative array that
>>>> returns an associated delegate, then call the delegate.
>>>>
>>>> The dynamic part will be loading up the associative array at run time.
>>> This is not exactly what everyone of us expected. I'd like to have
>>> something like
>>>
>>> void foo(Object o) {
>>>   o.duckMethod();
>>> }
>>>
>>> foo(new Object() { void duckMethod() {} });
>>>
>>> The feature isn't very dynamic since the dispatch rules are defined
>>> statically. The only thing you can do is rewire the associative array
>>> when forwarding statically precalculated dispatching.
>> I believe you should distinguish duck types from other types.
>>
>> You shouldn't be able to call duckMethod given a reference to Object,
>> it's a statically-typed language, after all.
> 
> Agreed. But this new feature is a bit confusing - there isn't anything 
> dynamic in it. It's more or less a compile time rewrite rule. It becomes 
> dynamic when all of that can be done on runtime and there are no 
> templates involved.

Yes, that's done via old-school forwarding.

Andrei