How do I find out if a tuple contains a type?

Question

Suppose I want to create a compile-time heterogenous container of unique types from some sequence of non-unique types. In order to do this I need to iterate over th

Answer 1

Since you asked for it, here is a boost::mpl version:

#include 
#include 
#include 
#include 

using namespace boost;

template
struct unique_concat : 
  mpl::unique>::type, 
              is_same> {};

template
struct print;

int main()
{
  typedef mpl::vector input;
  print::type> asdf;

  return 0;
}