The methods in a class have a special calling convention, which in Visual C++ is called __thiscall. The reason is that every method in a class has a hidden parameter called this, which is a pointer of the class type to the current instance:
class cartesian_vector { public: double x; double y; // other methods double get_magnitude() { return std::sqrt((this->x * this->x) + (this->y * this->y)); } };
Here, the get_magnitude method returns the length of the cartesian_vector object. The members of the object are accessed through the -> operator. As shown previously, the members of the class can be accessed without the this pointer, but it does make it explicit that the items are members of the class.
You could ...
