A local class is declared within a function definition. Declarations in a local class can only use type names, enumerations, static variables from the enclosing scope, as well as external variables and functions.
For example:
int x; // global variable void f() // function definition { static int y; // static variable y can be used by // local class int x; // auto variable x cannot be used by // local class extern int g(); // extern function g can be used by // local class class local // local class { int g() { return x; } // error, local variable x // cannot be used by g int h() { return y; } // valid,static variable y int k() { return ::x; } // valid, global x int l() { return g(); } // valid, extern function g }; } int main() { local* z; // error: the class local is not visible // ...}
Member functions of a local class have to be defined within their class definition, if they are defined at all. As a result, member functions of a local class are inline functions. Like all member functions, those defined within the scope of a local class do not need the keyword inline.
A local class cannot have static data members. In the following example, an attempt to define a static member of a local class causes an error:
void f() { class local { int f(); // error, local class has noninline // member function int g() {return 0;} // valid, inline member function static int a; // error, static is not allowed for // local class int b; // valid, nonstatic variable }; } // . . .
An enclosing function has no special access to members of the local class.
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