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From: postmast.root.admi.gov@iname.com (blargg)
Subject: Re: Suggestion: "typeof" keyword
Date: 1999/08/19
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In article <37BBDDCA.90D590D4@physik.tu-muenchen.de>, Christopher Eltschka
<celtschk@physik.tu-muenchen.de> wrote:

> "Siemel B. Naran" wrote:
> > 
> > On 13 Aug 99 15:52:23 GMT, Lisa Lippincott
> > 
> > >/* what type goes here? */
> > >MultiplyAdd( const A& a, const B& b, const C& c )
> > >  { return a * b + c; }
> > 
> > In one of my posts I used this
> >    typeof(A*B+C) MultiplyAdd(...) { ... }
> 
> That's problematic:
> 
> class X {};
> class Y { Y operator*(); };
> X operator*(X, Y);
> Y operator*(X*, Y);
> 
> typeof(X**Y) a
> 
> Is a of type X or of type Y?
> (That is, is the first star the multiplication operator and the
> second one the dereference operator, or is the first one part of
> the type, making a pointer to X, and the second one the
> multiplication operator?)

As I said before (in case anyone missed it),

    template<typename T> // heh, I almost typed "typeof" instead of "typename"
    T make_type();

    typeof (make_type<X>() * *make_type<Y>())


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