Functor for selecting the first element of a pair. More...
#include <select.h>
Public Member Functions | |
Pair::first_type & | operator() (Pair &x) const |
Return a reference to the first element. | |
const Pair::first_type & | operator() (const Pair &x) const |
Return a const reference to the first element. |
Functor for selecting the first element of a pair.