1fe6e33a3SDouglas Gregor // RUN: %clang_cc1 -std=c++0x -fsyntax-only -verify %s 2fe6e33a3SDouglas Gregor 3fe6e33a3SDouglas Gregor // Example tuple implementation from the variadic templates proposal, 4*b41e2d92SDouglas Gregor // ISO C++ committee document number N2080. 5fe6e33a3SDouglas Gregor 6fe6e33a3SDouglas Gregor // Helper type traits 7fe6e33a3SDouglas Gregor template<typename T> 8fe6e33a3SDouglas Gregor struct add_reference { 9fe6e33a3SDouglas Gregor typedef T &type; 10fe6e33a3SDouglas Gregor }; 11fe6e33a3SDouglas Gregor 12fe6e33a3SDouglas Gregor template<typename T> 13fe6e33a3SDouglas Gregor struct add_reference<T&> { 14fe6e33a3SDouglas Gregor typedef T &type; 15fe6e33a3SDouglas Gregor }; 16fe6e33a3SDouglas Gregor 17fe6e33a3SDouglas Gregor template<typename T> 18fe6e33a3SDouglas Gregor struct add_const_reference { 19fe6e33a3SDouglas Gregor typedef T const &type; 20fe6e33a3SDouglas Gregor }; 21fe6e33a3SDouglas Gregor 22fe6e33a3SDouglas Gregor template<typename T> 23fe6e33a3SDouglas Gregor struct add_const_reference<T&> { 24fe6e33a3SDouglas Gregor typedef T &type; 25fe6e33a3SDouglas Gregor }; 26fe6e33a3SDouglas Gregor 27fe6e33a3SDouglas Gregor template<typename T, typename U> 28fe6e33a3SDouglas Gregor struct is_same { 29fe6e33a3SDouglas Gregor static const bool value = false; 30fe6e33a3SDouglas Gregor }; 31fe6e33a3SDouglas Gregor 32fe6e33a3SDouglas Gregor template<typename T> 33fe6e33a3SDouglas Gregor struct is_same<T, T> { 34fe6e33a3SDouglas Gregor static const bool value = true; 35fe6e33a3SDouglas Gregor }; 36fe6e33a3SDouglas Gregor 37fe6e33a3SDouglas Gregor template<typename T> 38fe6e33a3SDouglas Gregor class reference_wrapper { 39fe6e33a3SDouglas Gregor T *ptr; 40fe6e33a3SDouglas Gregor 41fe6e33a3SDouglas Gregor public: 42fe6e33a3SDouglas Gregor reference_wrapper(T& t) : ptr(&t) { } 43fe6e33a3SDouglas Gregor operator T&() const { return *ptr; } 44fe6e33a3SDouglas Gregor }; 45fe6e33a3SDouglas Gregor 46fe6e33a3SDouglas Gregor template<typename T> reference_wrapper<T> ref(T& t) { 47fe6e33a3SDouglas Gregor return reference_wrapper<T>(t); 48fe6e33a3SDouglas Gregor } 49fe6e33a3SDouglas Gregor template<typename T> reference_wrapper<const T> cref(const T& t) { 50fe6e33a3SDouglas Gregor return reference_wrapper<const T>(t); 51fe6e33a3SDouglas Gregor } 52fe6e33a3SDouglas Gregor 53fe6e33a3SDouglas Gregor template<typename... Values> class tuple; 54fe6e33a3SDouglas Gregor 55fe6e33a3SDouglas Gregor // Basis case: zero-length tuple 56fe6e33a3SDouglas Gregor template<> class tuple<> { }; 57fe6e33a3SDouglas Gregor 58fe6e33a3SDouglas Gregor template<typename Head, typename... Tail> 59fe6e33a3SDouglas Gregor class tuple<Head, Tail...> : private tuple<Tail...> { 60fe6e33a3SDouglas Gregor typedef tuple<Tail...> inherited; 61fe6e33a3SDouglas Gregor 62fe6e33a3SDouglas Gregor public: 63fe6e33a3SDouglas Gregor tuple() { } 64fe6e33a3SDouglas Gregor // implicit copy-constructor is okay 65fe6e33a3SDouglas Gregor 66fe6e33a3SDouglas Gregor // Construct tuple from separate arguments. 67fe6e33a3SDouglas Gregor tuple(typename add_const_reference<Head>::type v, 68fe6e33a3SDouglas Gregor typename add_const_reference<Tail>::type... vtail) 69fe6e33a3SDouglas Gregor : m_head(v), inherited(vtail...) { } 70fe6e33a3SDouglas Gregor 71fe6e33a3SDouglas Gregor // Construct tuple from another tuple. 72fe6e33a3SDouglas Gregor template<typename... VValues> tuple(const tuple<VValues...>& other) 73fe6e33a3SDouglas Gregor : m_head(other.head()), inherited(other.tail()) { } 74fe6e33a3SDouglas Gregor 75fe6e33a3SDouglas Gregor template<typename... VValues> tuple& 76fe6e33a3SDouglas Gregor operator=(const tuple<VValues...>& other) { 77fe6e33a3SDouglas Gregor m_head = other.head(); 78fe6e33a3SDouglas Gregor tail() = other.tail(); 79fe6e33a3SDouglas Gregor return *this; 80fe6e33a3SDouglas Gregor } 81fe6e33a3SDouglas Gregor 82fe6e33a3SDouglas Gregor typename add_reference<Head>::type head() { return m_head; } 83fe6e33a3SDouglas Gregor typename add_reference<const Head>::type head() const { return m_head; } 84fe6e33a3SDouglas Gregor inherited& tail() { return *this; } 85fe6e33a3SDouglas Gregor const inherited& tail() const { return *this; } 86fe6e33a3SDouglas Gregor 87fe6e33a3SDouglas Gregor protected: 88fe6e33a3SDouglas Gregor Head m_head; 89fe6e33a3SDouglas Gregor }; 90fe6e33a3SDouglas Gregor 91fe6e33a3SDouglas Gregor void test_tuple() { 92fe6e33a3SDouglas Gregor tuple<> t0a; 93fe6e33a3SDouglas Gregor tuple<> t0b(t0a); 94fe6e33a3SDouglas Gregor t0a = t0b; 95fe6e33a3SDouglas Gregor 96fe6e33a3SDouglas Gregor tuple<int> t1a; 97fe6e33a3SDouglas Gregor tuple<int> t1b(17); 98fe6e33a3SDouglas Gregor tuple<int> t1c(t1b); 99fe6e33a3SDouglas Gregor t1a = t1b; 100fe6e33a3SDouglas Gregor 101fe6e33a3SDouglas Gregor tuple<float> t1d(3.14159); 102fe6e33a3SDouglas Gregor tuple<float> t1e(t1d); 103fe6e33a3SDouglas Gregor t1d = t1e; 104fe6e33a3SDouglas Gregor 105fe6e33a3SDouglas Gregor int i; 106fe6e33a3SDouglas Gregor float f; 107fe6e33a3SDouglas Gregor double d; 108fe6e33a3SDouglas Gregor tuple<int*, float*, double*> t3a(&i, &f, &d); 109fe6e33a3SDouglas Gregor } 110fe6e33a3SDouglas Gregor 111fe6e33a3SDouglas Gregor // Creation functions 112fe6e33a3SDouglas Gregor template<typename T> 113fe6e33a3SDouglas Gregor struct make_tuple_result { 114fe6e33a3SDouglas Gregor typedef T type; 115fe6e33a3SDouglas Gregor }; 116fe6e33a3SDouglas Gregor 117fe6e33a3SDouglas Gregor template<typename T> 118fe6e33a3SDouglas Gregor struct make_tuple_result<reference_wrapper<T> > { 119fe6e33a3SDouglas Gregor typedef T& type; 120fe6e33a3SDouglas Gregor }; 121fe6e33a3SDouglas Gregor 122fe6e33a3SDouglas Gregor template<typename... Values> 123fe6e33a3SDouglas Gregor tuple<typename make_tuple_result<Values>::type...> 124fe6e33a3SDouglas Gregor make_tuple(const Values&... values) { 125fe6e33a3SDouglas Gregor return tuple<typename make_tuple_result<Values>::type...>(values...); 126fe6e33a3SDouglas Gregor } 127fe6e33a3SDouglas Gregor 128fe6e33a3SDouglas Gregor template<typename... Values> 129fe6e33a3SDouglas Gregor tuple<Values&...> tie(Values&... values) { 130fe6e33a3SDouglas Gregor return tuple<Values&...>(values...); 131fe6e33a3SDouglas Gregor } 132fe6e33a3SDouglas Gregor 133fe6e33a3SDouglas Gregor template<typename T> const T *addr(const T& ref) { return &ref; } 134fe6e33a3SDouglas Gregor void test_creation_functions() { 135fe6e33a3SDouglas Gregor int i; 136fe6e33a3SDouglas Gregor float f; 137fe6e33a3SDouglas Gregor double d; 138fe6e33a3SDouglas Gregor const tuple<int, float&, const double&> *t3p = addr(make_tuple(i, ref(f), cref(d))); 139fe6e33a3SDouglas Gregor const tuple<int&, float&, double&> *t3q = addr(tie(i, f, d)); 140fe6e33a3SDouglas Gregor } 141fe6e33a3SDouglas Gregor 142fe6e33a3SDouglas Gregor // Helper classes 143fe6e33a3SDouglas Gregor template<typename Tuple> struct tuple_size; 144fe6e33a3SDouglas Gregor 145fe6e33a3SDouglas Gregor template<typename... Values> struct tuple_size<tuple<Values...> > { 146fe6e33a3SDouglas Gregor static const int value = sizeof...(Values); 147fe6e33a3SDouglas Gregor }; 148fe6e33a3SDouglas Gregor 149fe6e33a3SDouglas Gregor int check_tuple_size_0[tuple_size<tuple<> >::value == 0? 1 : -1]; 150fe6e33a3SDouglas Gregor int check_tuple_size_1[tuple_size<tuple<int>>::value == 1? 1 : -1]; 151fe6e33a3SDouglas Gregor int check_tuple_size_2[tuple_size<tuple<float, double>>::value == 2? 1 : -1]; 152fe6e33a3SDouglas Gregor int check_tuple_size_3[tuple_size<tuple<char, unsigned char, signed char>>::value == 3? 1 : -1]; 153fe6e33a3SDouglas Gregor 154fe6e33a3SDouglas Gregor template<int I, typename Tuple> struct tuple_element; 155fe6e33a3SDouglas Gregor 156fe6e33a3SDouglas Gregor template<int I, typename Head, typename... Tail> 157fe6e33a3SDouglas Gregor struct tuple_element<I, tuple<Head, Tail...> > { 158fe6e33a3SDouglas Gregor typedef typename tuple_element<I-1, tuple<Tail...> >::type type; 159fe6e33a3SDouglas Gregor }; 160fe6e33a3SDouglas Gregor 161fe6e33a3SDouglas Gregor template<typename Head, typename... Tail> 162fe6e33a3SDouglas Gregor struct tuple_element<0, tuple<Head, Tail...> > { 163fe6e33a3SDouglas Gregor typedef Head type; 164fe6e33a3SDouglas Gregor }; 165fe6e33a3SDouglas Gregor 166fe6e33a3SDouglas Gregor int check_tuple_element_0[is_same<tuple_element<0, tuple<int&, float, double>>::type, 167fe6e33a3SDouglas Gregor int&>::value? 1 : -1]; 168fe6e33a3SDouglas Gregor 169fe6e33a3SDouglas Gregor int check_tuple_element_1[is_same<tuple_element<1, tuple<int&, float, double>>::type, 170fe6e33a3SDouglas Gregor float>::value? 1 : -1]; 171fe6e33a3SDouglas Gregor 172fe6e33a3SDouglas Gregor int check_tuple_element_2[is_same<tuple_element<2, tuple<int&, float, double>>::type, 173fe6e33a3SDouglas Gregor double>::value? 1 : -1]; 174fe6e33a3SDouglas Gregor 175fe6e33a3SDouglas Gregor // Element access 176fe6e33a3SDouglas Gregor template<int I, typename Tuple> class get_impl; 177fe6e33a3SDouglas Gregor template<int I, typename Head, typename... Values> 178fe6e33a3SDouglas Gregor class get_impl<I, tuple<Head, Values...> > { 179fe6e33a3SDouglas Gregor typedef typename tuple_element<I-1, tuple<Values...> >::type Element; 180fe6e33a3SDouglas Gregor typedef typename add_reference<Element>::type RJ; 181fe6e33a3SDouglas Gregor typedef typename add_const_reference<Element>::type PJ; 182fe6e33a3SDouglas Gregor typedef get_impl<I-1, tuple<Values...> > Next; 183fe6e33a3SDouglas Gregor public: 184fe6e33a3SDouglas Gregor static RJ get(tuple<Head, Values...>& t) { return Next::get(t.tail()); } 185fe6e33a3SDouglas Gregor static PJ get(const tuple<Head, Values...>& t) { return Next::get(t.tail()); } 186fe6e33a3SDouglas Gregor }; 187fe6e33a3SDouglas Gregor 188fe6e33a3SDouglas Gregor template<typename Head, typename... Values> 189fe6e33a3SDouglas Gregor class get_impl<0, tuple<Head, Values...> > { 190fe6e33a3SDouglas Gregor typedef typename add_reference<Head>::type RJ; 191fe6e33a3SDouglas Gregor typedef typename add_const_reference<Head>::type PJ; 192fe6e33a3SDouglas Gregor public: 193fe6e33a3SDouglas Gregor static RJ get(tuple<Head, Values...>& t) { return t.head(); } 194fe6e33a3SDouglas Gregor static PJ get(const tuple<Head, Values...>& t) { return t.head(); } 195fe6e33a3SDouglas Gregor }; 196fe6e33a3SDouglas Gregor 197fe6e33a3SDouglas Gregor template<int I, typename... Values> typename add_reference< 198fe6e33a3SDouglas Gregor typename tuple_element<I, tuple<Values...> >::type >::type 199fe6e33a3SDouglas Gregor get(tuple<Values...>& t) { 200fe6e33a3SDouglas Gregor return get_impl<I, tuple<Values...> >::get(t); 201fe6e33a3SDouglas Gregor } 202fe6e33a3SDouglas Gregor 203fe6e33a3SDouglas Gregor template<int I, typename... Values> typename add_const_reference< 204fe6e33a3SDouglas Gregor typename tuple_element<I, tuple<Values...> >::type >::type 205fe6e33a3SDouglas Gregor get(const tuple<Values...>& t) { 206fe6e33a3SDouglas Gregor return get_impl<I, tuple<Values...> >::get(t); 207fe6e33a3SDouglas Gregor } 208fe6e33a3SDouglas Gregor 209fe6e33a3SDouglas Gregor #if 0 210fe6e33a3SDouglas Gregor // FIXME: Not yet functional, because we aren't currently able to 211fe6e33a3SDouglas Gregor // extend a partially-explicitly-specified parameter pack. 212fe6e33a3SDouglas Gregor void test_element_access(tuple<int*, float*, double*&> t3) { 213fe6e33a3SDouglas Gregor int i; 214fe6e33a3SDouglas Gregor float f; 215fe6e33a3SDouglas Gregor double d; 216fe6e33a3SDouglas Gregor get<0>(t3) = &i; 217fe6e33a3SDouglas Gregor get<1>(t3) = &f; 218fe6e33a3SDouglas Gregor get<2>(t3) = &d; 219fe6e33a3SDouglas Gregor } 220fe6e33a3SDouglas Gregor #endif 221fe6e33a3SDouglas Gregor 222fe6e33a3SDouglas Gregor // Relational operators 223fe6e33a3SDouglas Gregor inline bool operator==(const tuple<>&, const tuple<>&) { return true; } 224fe6e33a3SDouglas Gregor 225fe6e33a3SDouglas Gregor template<typename T, typename... TTail, typename U, typename... UTail> 226fe6e33a3SDouglas Gregor bool operator==(const tuple<T, TTail...>& t, const tuple<U, UTail...>& u) { 227fe6e33a3SDouglas Gregor return t.head() == u.head() && t.tail() == u.tail(); 228fe6e33a3SDouglas Gregor } 229fe6e33a3SDouglas Gregor 230fe6e33a3SDouglas Gregor template<typename... TValues, typename... UValues> 231fe6e33a3SDouglas Gregor bool operator!=(const tuple<TValues...>& t, const tuple<UValues...>& u) { 232fe6e33a3SDouglas Gregor return !(t == u); 233fe6e33a3SDouglas Gregor } 234fe6e33a3SDouglas Gregor 235fe6e33a3SDouglas Gregor inline bool operator<(const tuple<>&, const tuple<>&) { return false; } 236fe6e33a3SDouglas Gregor 237fe6e33a3SDouglas Gregor template<typename T, typename... TTail, typename U, typename... UTail> 238fe6e33a3SDouglas Gregor bool operator<(const tuple<T, TTail...>& t, const tuple<U, UTail...>& u) { 239fe6e33a3SDouglas Gregor return (t.head() < u.head() || (!(t.head() < u.head()) && t.tail() < u.tail())); 240fe6e33a3SDouglas Gregor } 241fe6e33a3SDouglas Gregor 242fe6e33a3SDouglas Gregor template<typename... TValues, typename... UValues> 243fe6e33a3SDouglas Gregor bool operator>(const tuple<TValues...>& t, const tuple<UValues...>& u) { 244fe6e33a3SDouglas Gregor return u < t; 245fe6e33a3SDouglas Gregor } 246fe6e33a3SDouglas Gregor 247fe6e33a3SDouglas Gregor template<typename... TValues, typename... UValues> 248fe6e33a3SDouglas Gregor bool operator<=(const tuple<TValues...>& t, const tuple<UValues...>& u) { 249fe6e33a3SDouglas Gregor return !(u < t); 250fe6e33a3SDouglas Gregor } 251fe6e33a3SDouglas Gregor 252fe6e33a3SDouglas Gregor template<typename... TValues, typename... UValues> 253fe6e33a3SDouglas Gregor bool operator>=(const tuple<TValues...>& t, const tuple<UValues...>& u) { 254fe6e33a3SDouglas Gregor return !(t < u); 255fe6e33a3SDouglas Gregor } 256fe6e33a3SDouglas Gregor 257fe6e33a3SDouglas Gregor void test_relational_operators(tuple<int*, float*, double*> t3) { 258fe6e33a3SDouglas Gregor (void)(t3 == t3); 259fe6e33a3SDouglas Gregor (void)(t3 != t3); 260fe6e33a3SDouglas Gregor (void)(t3 < t3); 261fe6e33a3SDouglas Gregor (void)(t3 <= t3); 262fe6e33a3SDouglas Gregor (void)(t3 >= t3); 263fe6e33a3SDouglas Gregor (void)(t3 > t3); 264fe6e33a3SDouglas Gregor }; 265