The programming interface
The programming interface in the fragment in Listing 3 consists of the prototypes
- A constructor that receives initialization parameters.
- An overloaded plus operator function, presumably
allowing users of the class to add an integral number of days to the date
(without seeing the full definition of the overloaded operator function, we
can't be sure of its purpose).
The nomenclature you see in Listing 3 consists only of the
prototypes of the member functions.
The definition of the member functions must
be provided elsewhere.