Definition of Class _ class

1. Explicitly specify an inline member function

You can specify that a member is inline as its declaration within the class definition body. Inline can also be specified on a function definition outside the body of the class definition. It is legal to specify inline at the declaration and definition.

The definition of an inline member function must be visible in every source file that invokes the function. An inline member function that is not defined in the class definition body, whose definition should normally be placed in the same header file as the class definition.

2. A data member can be specified as a class type only if the class definition has already been previously present. If the type is not a full type, the data member can only be a pointer to that type or reference. (A class is called an incomplete type before it is defined after the declaration.) ）

Because a class cannot be defined until the class definition body is complete, the class cannot have data members of its own type. However, as long as the class name is present, it can be assumed that the class is declared, so that the data members of the class can make a pointer or reference only to the type of itself. For example:

Class Linkscreen {screen    window;    Linkscreen *next;    Linkscreen *prev;};

Definition of Class _ class