C + +: Heavy override hidden overload override overwrite

Http://www.cnblogs.com/qlee/archive/2011/07/04/2097055.html

Overloading, overwriting, and hiding of member functions
The overloading, overwriting (override) and hiding of member functions are easily confused, and C + + programmers have to figure out
concept, otherwise errors will be impossible to guard against.
8.2.1 Overloading and overwriting
Features that are overloaded by member functions:
(1) The same range (in the same class);
(2) The function has the same name;
(3) different parameters;
(4) The virtual keyword is optional.
Overrides refer to a derived class function overriding a base class function, characterized by:
(1) different ranges (in the derived and base classes, respectively);
(2) The function has the same name;
(3) the same parameters;
(4) The base class function must have the virtual keyword.

8.2.2 confusing hidden rules
"Hide" here refers to a function of a derived class that masks a base class function with the same name as the following rule:
(1) If the function of the derived class has the same name as the function of the base class, but the parameters are different (return type is not considered). At this point, the function of the base class is hidden, regardless of the virtual keyword (Note that it is not confused with overloading).
(2) If the function of the derived class has the same name as the function of the base class, and the parameters are the same (the return type must be the same) and the base class function does not have the virtual keyword . At this point, the function of the base class is hidden (be careful not to confuse the overlay).

(2) If the return type is different, a compilation error occurs, and (2) the condition base function has virtual is overwritten.

C + +: Heavy override hidden overload override overwrite