[Mono-list] Re: Is Objective-C support possible?
Thomas F. Burdick
Fri, 15 Feb 2002 13:09:24 -0800
Martin Coxall writes:
> > > In any case the CLR is designed to avoid that by making its requirement of
> > > multiply inherited classes be abstract, so if you want broken OO via impure
> > > Mixins, I wouldn't expect the CLR to ever support that. ILX would still
> > > support the CLR notion of single inheritance, multiple interfaces.
> > You're talking about interfaces, not mixins. The term came from the
> > Flavors object system for Lisp, and mixins *do* come with
> > implementations. They're little classes that aretn't terribly useful
> > by themselves, but when mixed in with a substantial class, add
> > functionality.
> Which from a modern OO perspective is a Very Bad Thing. Which is why
> neither Java nor C# support them.
Bah. You seem to have missed the point that the OP was asking about:
whether the .NET CLR can support more than just languages that look
like C#. I would agree that mixin classes would be a bad idea in Java
or C#. But not all languages are like C#. For dynamically-typed
languages, mixins do *not* break encapsulation.
> To achieve what you want without breaking encapsulation, use the
> decorator pattern. Again if refer to Gang of Four.
Such patterns are specific to languages like C++. They apply somewhat
to Smalltalk, but really little at all to Lisp.
,' .\ / | No to Imperialist war |
,--' _,' | Wage class war! |
/ / `-----------------------'
( -. |
| ) |