Class/header file question

Hi,
I am trying to create a very basic class but keep getting an undefined reference error. I am confused about what this error means, and when searching online, I was unable to find any complete answer. Any help would be greatly appreciated. Here is my code:

Code:

---

//My main/driver
#include <iostream>
#include "Example.h"
using std::cout;
using std::endl;

int main() {
        cout << "THIS IS AN EXAMPLE" << endl;
        Example sample;
        sample.print();
return 0;
}


//My example class, i just want it to print out something.
#include <iostream>
using std::cout;
using std::endl;

class Example
{
        void print() {
                cout << "THIS IS NOW PRINTING IN THE CLASS" << endl;
        }
};

//My header file:
#include <iostream>
using std::cout;
using std::endl;

class Example
{
        public:
                void println();
};

---

I am compiling on unix by typing g++ -o main main.cpp and as I mentioned before, it returns an undefined reference error.
Thanks for any help anyone can give me.

type

Code:

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g++ -o main main.cpp example.cpp

---

Kurt

Quote:

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Originally Posted by ZuK

type

Code:

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g++ -o main main.cpp example.cpp

---

Kurt

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When I do that, the undefined reference error is now gone, but then I get two new errors:
Example.cpp: redefinition of 'class Example'
Example.h: previous definition of 'class Example'

1. Your header file should have header guards.
2. Your implementation should be written as:

Code:

---

//My example class, i just want it to print out something.
#include <iostream>
#include "Example.h"

using std::cout;
using std::endl;

void Example::print() {
    cout << "THIS IS NOW PRINTING IN THE CLASS" << endl;
}

---

Incidentally, you should remove your using directives from your header file, so as to avoid contaminating the namespace of whatever source file that the header is included in.

Thanks so much for your help,
Its working now.