#include <string>
#include <future>

struct X
{
    void foo(int,std::string const&);
    std::string bar(std::string const&);
};


X x;
auto f1=std::async(&X::foo,&x,42,"hello");
auto f2=std::async(&X::bar,x,"goodbye");

struct Y
{
    double operator()(double);
};
Y y;
auto f3=std::async(Y(),3.141);
auto f4=std::async(std::ref(y),2.718);
X baz(X&);
auto f6=std::async(baz,std::ref(x));
class move_only
{
public:
    move_only();
    move_only(move_only&&);
    move_only(move_only const&) = delete;
    move_only& operator=(move_only&&);
    move_only& operator=(move_only const&) = delete;
    void operator()();
};
auto f5=std::async(move_only());