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conversion to a reference warning......

Hi, I have a sample app which was written for MFC but I now have to convert the code to unix.

I have a class called Range which is derived from a structure RANGE :

Code:

typedef struct _tag_RANGE

{

        ANGLE start;

        ANGLE size;

        //ANGLE max;

} RANGE;

There is an operator in class Range defined as:

Code:

public:

//operators

operator RANGE& () { return dynamic_cast<RANGE&>(*this); };

When I build my app I get a warning:

Quote:

Range.h:108: warning: conversion to a reference to a base class will never use a type conversion operator

How can I get rid of this warning and it would be great if someone could explain why it is happening?

Thanks

Quote:

Range.h:108: warning: conversion to a reference to a base class will never use a type conversion operator

The compiler is correct, the conversion is implicit therefore making the operator redundant.

Quote:

How can I get rid of this warning

Really simply remove the operator :)

See below for example

Code:

typedef int ANGLE;

struct RANGE

{

        RANGE(ANGLE const& s,ANGLE const& sz):start(s),size(sz){}

        ANGLE start;

        ANGLE size;

};



struct Range : public RANGE

{

        Range(ANGLE const& s,ANGLE const& sz):RANGE(s,sz){}

};



#include <iostream>

int main()

{

        Range r(1,2);

        RANGE& rr(r);

        std::cout <<rr.start <<" " <<rr.size <<std::endl;

}

}