Thread: multiple operators in functors

Hi
I understand using functors and the operator however I was wondering if you can have more than one method in a class that can be called as though its a function?
so if I had

Code:

class add_x {
  add_x(int x) : x(x) {} //set member variable to value passed in
  int operator()(int y) { return x + y; }

private:
  int x;
};

then in main:

add_x adder(2); // create an instance of the functor class
int i = adder(8); // and "call" it
serial.printf("%d\n", i);

what if there was another method on add_x class called double
could I have another operator in some way that called that method double so whatever number was passed to it it doubled..?

Do I need templates for this or something?

Thanks

O_o

Your questions don't really make sense.

1): Methods are functions. You are never calling a method "as though its a function" because they are functions.

2): You can have as many overloads of the call operator as you wish. Methods are really just flavorful functions; you can overload them as normal. As with function overloading, you can't have two methods with the same signature visible in the same scope performing a different operation.

3): You can have a method named almost anything you like. You can basically have any method call any other method. The call operator can call any other method you like as it is, as before, basically just a function; it only has a special name.

4): Why would a class named `add_x' ever perform an operation called "double"? Why not just have a class named "double"? (You can't call it "double", but that's not the point.)

5): You don't need templates. You can use templates. I'd even recommend that you use templates so that the types operated on are appropriate to the purpose.

Soma

I just made "double" up as I was typing to try and give an example of another thing I might want that class to be able to do. Sorry for confusion, I understand I could just make another class to do the job, but Im thinking of a situation where you may need to be able to treat an object as a function but also be able to do more than just one thing with it?
I can overload the operator as long as Im not passing it the same types right?