Thread: Linker Error In Template Code

Hi team

I was working on template and found the linker error while compiling the code.

Below is the code:

Code:

//Template1.h: Header file where template define

#ifndef __Template1_H__  
#define __Template1__  
                      


template <typename T,typename T1> class A
{
 
	T a;
	T1 b;

	public:
		A(T ,T1 ) ;

		void getData();
		
};
#endif // __

Code:

//Template1.cpp where class define

#include<iostream>
#include<string>

#include "Template1.h"

using namespace std;





template<typename T,typename T1> A<T,T1>:: A(T x,T1 y)
{
 a = x;
 b = y;
}

 template<typename T,typename T1> void A<T,T1>:: getData()
{
 cout<< a << b;
}

Code:

// Main Class from where code called:Template2.cpp

#include<iostream>
#include<string>

#include "Template1.h"

int main()
{

   A<int,char> f(1,'d');

   f.getData();

   
   getchar();
   return 0;
}

I am getting below linker error:

Template2.obj : error LNK2001: unresolved external symbol "public: void __thiscall A<int,char>::getData(void)" (?getData@?$A@HD@@QAEXXZ)

Template2.obj : error LNK2001: unresolved external symbol "public: __thiscall A<int,char>::A<int,char>(int,char)" (??0?$A@HD@@QAE@HD@Z)

Can anyone help in this.

Thanks

Thanks for reply.

I was too reading that link. I am using class, so how can I declare member function as extern? As shown in link.
Is there some other syntax for Class ?

Could you please help.

Thanks
Nickman

Yes. By defining in header it was working fine. But I want to try the solution in the link. But it was not working.
Am I doing something wrong?

Also,as link suggest that make function as extern will not work in case of class member function..right?

thanks
Nickman

I tried this in Template1.h


I tried this in Template1.h

Code:

 template<typename T,typename T1> extern  void getData();

In Template1.cpp

Code:

template<typename T,typename T1> void getData();

And got error:

c:\c++\template1\template1.h(15) : error C2720: 'getData' : 'extern' storage-class specifier illegal on members

I tried this also:

Code:

extern void getData();

But same result.

Thanks