Jump to content
  • Advertisement
Sign in to follow this  
nlbs

One template question

This topic is 3541 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

template <typename T, typename CONT /*= std::vector*/ > 
struct Stack{
    CONT elem;
};
The above code compiles fine as it should be If I just uncomment the std::vector one it fires compilation errors saying
error: expected type-specifier
error: expected '>'
But I don't find any syntactic or symantic error in the above code. can anybody please point it out.

Share this post


Link to post
Share on other sites
Advertisement
It's because std::vector is a templated type too, so you need to specify something for it to template on. For example, template <typename T, typename CONT = std::vector<int> > will work because now the compiler knows 'a vector of what?'

Share this post


Link to post
Share on other sites
You probably wanted:

template <typename T, typename CONT = std::vector<T> >
struct Stack{
CONT elem;
};

Share this post


Link to post
Share on other sites
For std::vector to be considered a complete type it needs its one parameter specified. You might want something like this


template <typename T, typename CONT = std::vector<T> >
struct Stack{
CONT elem;
};




And as they say... ninja'd... twice :p

Share this post


Link to post
Share on other sites
You can do what you want by using template template parameters:

#include <vector>

template<typename T, template<typename T, typename Alloc> class CONT = std::vector>
struct Stack{
CONT<T, std::allocator<T> > elem;
};


int main()
{
Stack<int, std::vector> s;
return 0;
}


[Edited by - D_Tr on December 5, 2008 10:26:07 AM]

Share this post


Link to post
Share on other sites
Thanks all understood
I forgot that std::vector does not name a type rather std::vector<SOMETYPE> is a Typename

Share this post


Link to post
Share on other sites
Sign in to follow this  

  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

We are the game development community.

Whether you are an indie, hobbyist, AAA developer, or just trying to learn, GameDev.net is the place for you to learn, share, and connect with the games industry. Learn more About Us or sign up!

Sign me up!