Operator Overloading
	• We cannot change the.... – number of operands an operator expects – precedence and associativity of operators – or use default arguments with operators • We should not change... – the meaning of the operator (+ does not mean subtraction!) – the nature of the operator (3+4  == 4+3) – the data types and residual value expected – whether it is an rvalued or lvalued result – provide consistent definitions (if + is overloaded, then += should also be)