Overloading in C++

• Two operators that need not be overloaded: assignment (=), address (&)
• Operators that cannot be overloaded
  • member (.), scope resolution (::), ternary operator (?:), sizeof, .*
• Cannot overload non-existent operator symbols
• Cannot change precedence, associativity, arity
• At least one operand must be user-defined type
• Two mechanisms:
  • Member
    • Assignment operator must be overloaded as member
      • To prevent different behaviors before and after the non-member function definition
  • Non-Member (friend for efficiency)
    • When first operand is not an object of the type
    • When commutativity desired
• Dynamic data members:
  • Overload assignment
    • Avoid self-assignment!
  • Copy constructor
• Overloading prefix versus postfix operator
  • Use this operator