Apple Certification Exam 9L0-509

The subscript operator, [ ], is a binary operator which must be a member function (hence it takes only 9L0-509 one explicit parameter, the index). The subscript operator is not limited to taking an integral index. For instance, the index for the subscript operator for the std::map template is the same as the type of the key, so it may be a string etc. The subscript operator is generally overloaded twice; as a non-constant function (for when elements are altered), 9L0-402 Questions and as a constant function (for when elements are only accessed).

The function call operator, ( ), is generally overloaded to create objects which behave like functions, or for classes that have a primary operation. The function call operator 9L0-509 must be a member function, but has no other restrictions - it may be overloaded with any number of parameters of any type, and may return any type. A class may also have several definitions for the function call operator.

These three operators, operator&(), operator*() and operator->() can be overloaded. In general these operators are only overloaded for smart pointers, or classes which attempt to mimic Apple 9L0-402 the behavior of a raw pointer. The pointer operator, operator->() has the additional requirement that the result of the call to that operator, must return a pointer, or a class with an overloaded operator->(). In general A == *&A should be true.