How do you create an optional parameter in a class method?

Question

I know that to create an optional parameter in a function you can do this:

void exemplo(int a,int b=0);

But how do I do it in a class function
ex:

class Exemplo{
    public:
    void nada(int,int);
};
void Exemplo::nada(int a,int b){}

This would be an example with "normal" parameters, to try to leave the optional (b) I did:

void Exemplo::nada(int a,int b=0){}

but when calling the compiler function says I need to put (b), probably because in that statement it is not optional:

void nada(int,int);

How can I solve this problem, remembering that I do not want a constructor with optional parameters but another function.

Answer 1

It’s the same thing:

#include <iostream>

class Exemplo {
    public:
    void nada(int a, int b = 0);
};
void Exemplo::nada(int a, int b) { std::cout << b; }

int main() {
    Exemplo x = Exemplo();
    x.nada(1);
}

Behold working in the ideone. And in the repl it.. Also put on the Github for future reference.