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D - functions, delegates and templates

I have never used delegates in my life. Now I'm trying to start with D. I
think this should be legal:

template gen (T) {
    T max (T a,T b) {
        return (a>b?a:b);
    }

    bit comp(T a,T b,T delegate (T,T) f) {      /*************/
       return a==f(a,b);
    }
}

instance gen(int) intGen;
instance gen(real) realGen;
instance gen(char[]) strGen;

void main() {
    int a=45,b=32;
    real c=-12.3,d=2.4;
    char[] e='hola',f='chao';

    intGen.comp(a,b,intGen.max);
    realGen.comp(c,d,realGen.max);
    strGen.comp(e,f,strGen.max);
}

If I change delegate for function in the comp function, it doesn't work
either. Both ways, I get non-matching arguments. Is the code correct or am I
missing something?
The workaround that I've tried was to declare as a function, and also
declare 3 function pointers in main pointing to each max function, but I
think there must be another way to do it.


-------------------------
Carlos Santander


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