#398 – Overloadable Operators

When you define an operator for a class, you are defining the behavior for that operator when acting upon instances of the class.  This is also known as overloading the operator.

You can overload any of the operators listed below.

• Unary operators  (apply to one operand):  +, -, !, ~, ++, –, true, false
• Binary operators  (apply to two operands):  +, -, *, /, %, &, |, ^, <<, >>
• Comparison operators  (apply to two operands): ==, !=, <, >, <=, >=

When you overload the comparison operators, you must overload them in pairs:

• Implement ==, != together
• Implement <, > together
• Implement <=, >= together