As you may know, I have been developing a game engine using OpenGL and C++. I have tried learning as much about C++ as I could. Recently I decided to reread the Effective C++ book and apply what I have learned from the book into the engine. However, I also decided that I should also share with you what I learn. Today I read the following tip in the Effective C++ book:

Have assignment operators(=,+=,-+,*=,etc.) return a reference to *this

For example, the method below; since its an assignment, should be written as follows:

class Point{
        public:
        //...
        //this is an assignment operator
        Point& operator=(const Point& rhs){

        //...
        //Thus, make sure to return *this
        return *this;
        }
    }

The same applies to any other assignment operators such as: +=,-=, *=, etc

class Point{
        public:
        //...
        //this is another assignment operator
        Point& operator+=(const Point& rhs){

        //...
        //So, also make sure to return *this
        return *this;
        }
    }

This is a convention, any code that doesn't follow this rule will compile just fine. However, this convention is used by all built-in types and the standard library, so it is a good idea for you to follow it as well.

C++ tip 6: Have assignment operators return a reference to *this

Harold Serrano