15 class Emplaceable
17     Emplaceable(const Emplaceable&);
18     Emplaceable& operator=(const Emplaceable&);
23     Emplaceable() : int_(0), double_(0) {}  in Emplaceable()  function
24     Emplaceable(int i, double d) : int_(i), double_(d) {}  in Emplaceable()  function
25     Emplaceable(Emplaceable&& x)  in Emplaceable()  function
28     Emplaceable& operator=(Emplaceable&& x)
33     bool operator==(const Emplaceable& x) const
35     bool operator<(const Emplaceable& x) const
44 struct hash<Emplaceable>
45     : public std::unary_function<Emplaceable, std::size_t>
47     std::size_t operator()(const Emplaceable& x) const {return x.get();}