How to fix error my function is not define?

Asked May 07 '20 at 13:03

Active May 07 '20 at 13:03

Viewed 21 times

int main()
 {
    Pair<int, int> A = makePair (10, 20);
    cout << A ;
 return 0;
}

it give me error here (makePair is not define) and i define it in header file

template<class T1, class T2>
class Pair{
private:
    T1 first;
    T2 second;
public:
    Pair(T1, T2);
    Pair() {};
    Pair<T1, T2>  makePair(T1  a, T2  b);
    void operator==(const Pair& other);
    friend ostream& operator<<(ostream& out, const Pair<T1, T2>& A);
};

and this is another file called pair.cpp that i used a template classes in it

template<class T1, class T2>
Pair<T1, T2> makePair(T1   a, T2   b)
{
    return (Pair<T1, T2>(a, b));
}

asked May 07 '20 at 13:03

Sophia John

did you #include your header file? – nivpeled May 07 '20 at 13:06
Are you including the header file that defines `makePair` with a `#include` directive? Your code with `main` is incomplete. – h0r53 May 07 '20 at 13:06
@SophiaJohn the `includes` part of the file is the most important part for the issue you are describing, so you should provide it as well. – h0r53 May 07 '20 at 13:09
so what's the solution ? – Sophia John May 07 '20 at 13:10
1

Move `makePair` into a header file. All templates should go into header files. – Evg May 07 '20 at 13:11
Read the above link, you cannot split templates into .h/.cpp files – Cory Kramer May 07 '20 at 13:16

How to fix error my function is not define?

0 Answers0