returning a class

hi
I want to return a class in a function but i don't want really to declare it. I want to do something like:

Code:

---

#include <cstdio>

class wynik
{
public:
        int    a,
                b;
        wynik(int _a =0, int _b =0)
        {
                a=_a;
                b=_b;
        }
};

wynik  f(int i, int y)
{
        return (i, y);
}

int main()
{
        wynik lala;
        lala=f(12,14);
        printf("%d %d\n", lala.a, lala.b);
        return 0;
}

---

but on the output i don't see 12 14 but 14 0. Can anyone tell me if something like that is possible or i have to code f() like:

Code:

---

wynik  f(int i, int y)
{
        wynik a(i,y);
        return a;
}

---

Regards.
apacz

Your first method will not work, you must use something like the second method.

Code:

---

Foo f(int x, int y)
{
  return Foo(x, y);
}

---

That's how I would write it.

I'm sure you'll probably get the same amount of replies here as you would on any other C board, but, if I am correct, you might want to post this on the board for C, this is a board for C++ and most people who know about C will be hanging out at the other board, good luck!

>if I am correct, you might want to post this on the board for C, this is a board for C++
:confused: class == C++

You can use pointers or references to change multiple variables inside a function (without returning anything).

Or, the value returned by a function can be pointer. It can be a simple pointer to a variable, or a pointer to an array, a pointer to a structure, or a pointer to an object, etc.

you have to create a copy constructor. You should also provide a operator=

With that class you don't have to create a copy constructor or copy assignment operator=, the ints will be copied correctly automatically.

yes, but good practices pay up. If he had a ponter to allocated memory, that implementation would be troublesome....

IMHO, good practice is to only implement a copy constructor, copy assignment operator, and destructor when it is necessary, and leave comments that you are using the default versions if it is not obvious. Once you've written them, you must remember to maintain them every time you change the implementation of the class.