final Specifier
The latest version of this topic can be found at final Specifier.
You can use the final
keyword to designate virtual functions that cannot be overridden in a derived class. You can also use it to designate classes that cannot be inherited.
Syntax
function-declaration final;
class class-name final base-classes
Remarks
final
is context-sensitive and has special meaning only when it's used after a function declaration or class name; otherwise, it's not a reserved keyword.
When final
is used in class declarations, base-classes
is an optional part of the declaration.
Example
The following example uses the final
keyword to specify that a virtual function cannot be overridden.
class BaseClass
{
virtual void func() final;
};
class DerivedClass: public BaseClass
{
virtual void func(); // compiler error: attempting to
// override a final function
};
For information about how to specify that member functions can be overridden, see override Specifier.
The next example uses the final
keyword to specify that a class cannot be inherited.
class BaseClass final
{
};
class DerivedClass: public BaseClass // compiler error: BaseClass is
// marked as non-inheritable
{
};