operator overloading question

[fafner]

I have two classes, Vector3D and Normal. I need to define two operators for the Normal class for the following operations:

Normal normal;
Vector3D vector;

double a = normal * vector;
double b = vector * normal;

The first one I have defined like so:
double operator *(const Vector3D& v) const;

But how do I define/implement the other one?

[Bazzy]

You can implement operator* as an external function ( declaring two parameters instead of just one )

[M364M4Ncro]

uf u gonna declare it as external function, then u have to declre is as friend

[jsmith]

uf u gonna declare it as external function, then u have to declre is as friend

That is not necessarily true; it depends on what the external function does. For example:

class MyComplexNumber
{
    public:
        MyComplexNumber operator+( int rhs ) const { /* ... */ }
};

// This need not be a friend since it just calls a public member of MyComplexNumber:
inline MyComplexNumber operator+( int lhs, const MyComplexNumber& rhs )
    { return rhs + lhs; }

[fafner]

Thanks, everyone, that's exactly what I needed!