Subject: Re: [boost] [RFC] Protocol for operator. (dot) overloading
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2008-10-05 20:02:49
Corrado Zoccolo wrote:
> Hi boosters,
> I think that Adobe poly approach on "operator . overloading" could be
> extracted as orthogonal to the polymorphic object container concept, and
> easily generalized to serve all kinds of wrappers.
> My proposal (see code in the vault: *http://tinyurl.com/5xo9or*) is to have
> a class template (interface<T,W,B>) that describes the interface of type T,
> forwarding any operation to the implementation type, got directly from the
> wrapper (W). B is used when vertical inheritance is needed, either to
> benefit of EBO or to insert a base class on top of the hierarchy (see
> type_erasure_wrapper). There is actually a fourth boolean parameter, that
> will be explained later.
Such a complicated and specific mechanism.
I think a lot of people come up with lots of approaches at overloading
the dot operator which really do not truly overload its meaning.
What that operator takes is an an object, a name, and arguments.
Therefore, in my opinion, overloading the dot operator should mean
calling a function with a compile-time string and those arguments. Then,
with proper compile-time introspection support (an mpl map of
compile-time strings to functor types), one can for example choose to
call a member function with that name on some type, or do something else.
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