4 replies to this topic

[lukesmith123]

Hi,

I made a template class like this:

template<class identifier>
class myclass
{
public:
   void function();
};

and I want to define the function in a cpp file but I cant figure out how to do this. I tried this:

template<class identifier>
myclass::function()
{
   //---
}

but I get the error - use of template requires template argument list.

Is there any way I can define the functions for the class in a cpp file or would I just need to do it in the header?

thanks,

[SuperVGA]

Hi Luke,

Templates need to be explicitly defined.
- You need to implement the template function in the header like you suggested.

[Kraecker]

Hi there,

as SuperVGA said, you have to implement your methods / functions in the header file.

BUT you can include other files in those headers.

So you write your declaration in your header file and include the ".inl" file where your actual implementation is.

-- Edit --

Maybe take a look at http://stackoverflow.com/questions/1208028/significance-of-a-inl-file-in-c

[SiCrane]

To fix the compiler error you would change your code to:

template<class identifier>
void myclass<identifier>::function()
{
   //---
}

As noted above you'll get a linker error without explicit instantiation if you put that code in a source file.

[lukesmith123]

Ah ok thanks!