Return of indicator to function

[terrea]

How can the index be returned to function from function?

void f0(char) {}
void (*)(char) f1() {return f0;} // В возвращаемом типе ошибка

May I announce auto I'm not interested.

[kalena]

The following ways can be used to re-enter the function.

(1) Clear indication of type.

void (*f1())(char) { return f0; }

(2) Synonym announcement through typedef♪

typedef void (*TFunc)(char);
TFunc f1() { return f0; }

(3) Synonym announcement through using (sighs)c++11)

using TFunc = void (*)(char);
TFunc f1() { return f0; }

(4) Semi-automatic definition of re-entry typec++11)

auto f1() -> decltype(&f0) { return f0; }

(5) Automatic definition of re-entry type (c)c++14)

auto f1() { return f0; }