online compiler and debugger for c/c++

#include <iostream> template <class T, class U> struct Typelist { typedef T head; typedef U Tail; }; class NullType { }; template <typename T1 = NullType, typename T2 = NullType, typename T3 = NullType, typename T4 = NullType, typename T5 = NullType> class MakeList { typedef typename MakeList< T2, T3, T4, T5 >::Result Tail; public: typedef Typelist<T1, Tail> Result; }; template <> class MakeList<> { public: typedef NullType Result; }; template <class TList> struct Length; template <> struct Length< NullType > { enum { value = 0 }; }; template <class T, class U> struct Length< Typelist<T, U> > { enum { value = 1 + Length<U>::value }; }; template <class TList, unsigned int Index> struct TypeAt; template <class Head, class Tail> struct TypeAt<Typelist<Head, Tail>, 0> { typedef Head Result; }; template <class Head, class Tail, unsigned int Index> struct TypeAt<Typelist<Head, Tail>, Index> { typedef typename TypeAt<Tail, Index - 1>::Result Result; }; //============ Примитивная реализация Tuple с использованием списка типов ================== template <typename T, unsigned int I> class TupleElement { public: T & get() { return m_value; } private: T m_value; }; template <typename List, unsigned int I = 0> class TupleImpl; template <typename T, typename U, unsigned int I> class TupleImpl<Typelist<T, U>, I> : public TupleElement<T, I> , public TupleImpl<U, I + 1> { }; template <unsigned int I> class TupleImpl<NullType, I> { }; template < typename T1 = NullType, typename T2 = NullType, typename T3 = NullType, typename T4 = NullType, typename T5 = NullType > class Tuple : public TupleImpl<typename MakeList<T1, T2, T3, T4, T5>::Result> { typedef typename MakeList<T1, T2, T3, T4, T5>::Result ElementsList; public: template <unsigned int Index> typename TypeAt<ElementsList, Index>::Result & get() { TupleElement<typename TypeAt<ElementsList, Index>::Result, Index> & el = *this; return el.get(); } enum { Size = Length<ElementsList>::value }; }; //======================== Эмуляция перебора в цикле ==================================== template <typename Tuple, unsigned int I = Tuple::Size> struct TupleForEach_ { template <typename F> static void run(Tuple & tpl, F f) { TupleForEach_<Tuple, (I - 1)>::run(tpl, f); f(tpl.template get<(I - 1)>()); } }; template <typename Tuple> struct TupleForEach_<Tuple, 0> { template <typename F> static void run(Tuple & tpl, F f) { } }; template <typename Tuple, typename F> void TupleForEeach(Tuple & x, F f) { TupleForEach_<Tuple>::run(x, f); } //======================================================================= template<typename Tuple, unsigned int I = Tuple::Size> struct TupleFor__ { template<typename F> static void run(Tuple& tpl, F f, unsigned int i) { if (i == I - 1) f(tpl.template get<(I - 1)>()); else TupleFor__<Tuple, (I - 1)>::run(tpl, f, i); } }; template <typename Tuple> struct TupleFor__<Tuple, 0> { template <typename F> static void run(Tuple& tpl, F f, unsigned int i) { } }; template <typename Tuple, typename F> void TupleFor_(Tuple& t, F f, unsigned int i) { TupleFor__<Tuple>::run(t, f, i); } template<typename Tuple, typename F> void TupleFor(unsigned int first, unsigned int last, Tuple t, F f) { for (unsigned int i = first; i <= last; ++i) TupleFor_(t, f, i); } //======================================================================= struct CoutPrinter { template <typename T> void operator()(T const & v) const { std::cout << v << ' '; } }; int main() { Tuple<int, char, double, unsigned int> tpl; tpl.get<0>() = -12; tpl.get<1>() = 'a'; tpl.get<2>() = 3.14; tpl.get<3>() = 50; unsigned int a = 0; unsigned int b = 0; std::cin >> a; std::cin >> b; TupleFor(a, b, tpl, CoutPrinter()); }