Redefining operators

If you need to redefine operators remember to redefine then consistently (if you redefine '+' don't forget '+=') and remember that you can't change precedence order. The default assignment operator does a simple copy of members, which might not be what you want.

Examples of redefining operators are in most books. Some things to remember when redefining assignment operators are

• that reference parameters help to overload operators efficiently (objects aren't copied) while keeping their use intuitive (pointers would require the user to supply addresses of objects).
• to deal with situations where a variable is assigned to itself. A pointer/reference to the object on the right of the = will be given to the function explicitly. A pointer to the object that the function is a member of is supplied implicitly to all non-static member functions. It's called this, so if this equals the supplied pointer, you'd usually want to do nothing.

• to return a const. This catches errors like (i+j)=k

• to return *this so that assignments can be chained (i.e. i=j=k becomes possible)