c++ - Is it possible to call a member function for every type in a tuple? - 


namespace details { template <std::size_t = 0, typename tuple, typename function, typename... args> typename std::enable_if<i == std::tuple_size<tuple>::value, void>::type foreach(tuple &t, function f, args &... args) {}  template <std::size_t = 0, typename tuple, typename function, typename... args> typename std::enable_if<(i < std::tuple_size<tuple>::value), void>::type foreach(tuple &t, function f, args &... args) {     f(std::get<i>(t), args...);     foreach<i + 1>(t, f, args...); } }

an implementation foreach functionality types of tuple above. calls f(tuple_type, args...)

however want tuple_type.f(args...) f , args template arguments.

f member function of types in tuple, taking args... arguments.

template <typename... types> class tuplemanager {     std::tuple<types...> t;     template <typename function, typename... args>     void foreach(function f, args& ... args) {          details::foreach<>(t, f, args...);     } }

clarification: f needs member function, i.e function takes same name types in tuple.

eg: 

struct {     void foo() {         std::cout << "a's foo\n";     } }; struct b : {     void foo() {         std::cout << "b's foo\n";     } };  struct c : {     void foo() {         std::cout << "c's foo\n";     } };

but can't pass foo. passing &a::foo print's a's foo. requirement print a'foo object of in tuple, b's foo object of b in tuple, , c's foo object of c in tuple.

demo


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