How to use swift standard library types in cpp package?

Over the weekend I was trying to send some data from swift side to cpp side.
How do I import the following headers? Perhaps those are just arbitrary headers from the documentation, it was not clear to me.

#include <SwiftLibrary-Swift.h> //  fatal error: 'SwiftLibrary-Swift.h' file not found
#include <StringsAndNumbers-Swift.h>  //  fatal error: 'StringsAndNumbers-Swift.h' file not found

I also tried #include <swift/bridging> and its not able to find swift:: module. Thoughts?

#include <swift/bridging>

struct KeyGrid {

  std::vector<std::vector<Key*>> data;

  KeyGrid(swift::Array<Key*> input) //: error: use of undeclared identifier 'swift'
  {   
  //....
  };