Is there a way to check if a class is derived from another?
I mean something like "a.classinfo.isDerived(b.classinfo)".
Maybe object.d should include a function to do that.
I think it can be written as follows:
    class ClassInfo
    {
        byte[] init;
        char[] name;
        void*[] vtbl;
        Interface[] interfaces;
        ClassInfo base;
        void* destructor;
        void function(Object) _invariant;
        uint flags;
        void* deallocator;

        bit isDerived(ClassInfo c)
        {
            for(ClassInfo b=base; b!==Object.classinfo; b=b.base)
                if(b === c)
                    return true;
            return false;
        }
    }

I also have to advise the great confusion in the D math library.
"math.d" contains functions like "double pow(double,double)" and "real
pow(real,int)"
which inevitably conflicts with each other. Moreover I saw that the sin
function in "math.d"
is still the old C function, not the optimized D intrinsic one. These
conflicts together too.
I know that explicit casts can resolve any conflict, but I think that
explicit casts are
annoying and cumbersome. Why should "pow(3.0, 0.5);" be ambiguous?
Dario

"Dario" <supdar@yahoo.com> wrote in message news:b8kabs$75t$1@digitaldaemon.com...
> Is there a way to check if a class is derived from another?

Yes. Try a down cast, if it produces a non-null value it is derived from the other. For example:

class A { }
class B : A { }

int isB(A *a)
{
    return cast(B)A !== null;
}

> I also have to advise the great confusion in the D math library.
> "math.d" contains functions like "double pow(double,double)" and "real
> pow(real,int)"
> which inevitably conflicts with each other. Moreover I saw that the sin
> function in "math.d"
> is still the old C function, not the optimized D intrinsic one. These
> conflicts together too.
> I know that explicit casts can resolve any conflict, but I think that
> explicit casts are
> annoying and cumbersome. Why should "pow(3.0, 0.5);" be ambiguous?

I agree that all needs work.

Dario:
>> Is there a way to check if a class is derived from another?

Walter:
> Yes. Try a down cast, if it produces a non-null value it is derived from the other. For example:
>
> class A { }
> class B : A { }
>
> int isB(A *a)
> {
>    return cast(B)A !== null;
> }

Wow! =)