1// DR 339 2// 3// Test of the use of various binary operators with SFINAE 4 5// Boilerplate helpers 6typedef char yes_type; 7struct no_type { char data[2]; }; 8 9template<typename T> T create_a(); 10template<typename T> struct type { }; 11 12template<bool, typename T = void> struct enable_if { typedef T type; }; 13template<typename T> struct enable_if<false, T> { }; 14 15#define JOIN( X, Y ) DO_JOIN( X, Y ) 16#define DO_JOIN( X, Y ) DO_JOIN2(X,Y) 17#define DO_JOIN2( X, Y ) X##Y 18 19#define DEFINE_INFIX_BINARY_TRAIT(Name,Op) \ 20template<typename T, typename U> \ 21 typename enable_if<(sizeof(create_a<T>() Op create_a<U>(), 1) > 0), \ 22 yes_type>::type \ 23 JOIN(check_,Name)(type<T>, type<U>); \ 24 \ 25no_type JOIN(check_,Name)(...); \ 26 \ 27template<typename T, typename U = T> \ 28struct Name \ 29{ \ 30 static const bool value = \ 31 (sizeof(JOIN(check_,Name)(type<T>(), type<U>())) == sizeof(yes_type)); \ 32} 33 34template<typename T, typename U> 35 typename enable_if<(sizeof(create_a<T>()[create_a<U>()], 1) > 0), 36 yes_type>::type 37 check_subscript(int); 38 39template<typename T, typename U> 40 no_type check_subscript(...); 41 42template<typename T, typename U> 43struct can_subscript 44{ 45 static const bool value = 46 (sizeof(check_subscript<T, U>(0)) == sizeof(yes_type)); 47}; 48 49#ifdef __GXX_EXPERIMENTAL_CXX0X__ 50# define STATIC_ASSERT(Expr) static_assert(Expr, #Expr) 51#else 52# define STATIC_ASSERT(Expr) int JOIN(a,__LINE__)[Expr? 1 : -1] 53#endif 54 55struct X { }; 56struct Y { int operator[](X); }; 57 58// is_addable 59DEFINE_INFIX_BINARY_TRAIT(is_addable, +); 60X operator+(X, X); 61X operator+(X, Y); 62STATIC_ASSERT((is_addable<int>::value)); 63STATIC_ASSERT((is_addable<int, long>::value)); 64STATIC_ASSERT((is_addable<X>::value)); 65STATIC_ASSERT((is_addable<int*, int>::value)); 66STATIC_ASSERT((!is_addable<int*>::value)); 67STATIC_ASSERT((is_addable<X, Y>::value)); 68STATIC_ASSERT((!is_addable<Y>::value)); 69 70// is_subtractable 71DEFINE_INFIX_BINARY_TRAIT(is_subtractable, -); 72X operator-(X, X); 73X operator-(X, Y); 74STATIC_ASSERT((is_subtractable<int>::value)); 75STATIC_ASSERT((is_subtractable<int, long>::value)); 76STATIC_ASSERT((is_subtractable<X>::value)); 77STATIC_ASSERT((is_subtractable<int*, int>::value)); 78STATIC_ASSERT((is_subtractable<int*>::value)); 79STATIC_ASSERT((is_subtractable<X, Y>::value)); 80STATIC_ASSERT((!is_subtractable<Y>::value)); 81STATIC_ASSERT((!is_subtractable<int X::*>::value)); 82 83// is_multiplicable 84DEFINE_INFIX_BINARY_TRAIT(is_multiplicable, *); 85X operator*(X, X); 86X operator*(X, Y); 87STATIC_ASSERT((is_multiplicable<int>::value)); 88STATIC_ASSERT((is_multiplicable<int, long>::value)); 89STATIC_ASSERT((is_multiplicable<X>::value)); 90STATIC_ASSERT((!is_multiplicable<int*, int>::value)); 91STATIC_ASSERT((!is_multiplicable<int*>::value)); 92STATIC_ASSERT((is_multiplicable<X, Y>::value)); 93STATIC_ASSERT((!is_multiplicable<Y>::value)); 94STATIC_ASSERT((!is_multiplicable<int X::*>::value)); 95 96// is_divisible 97DEFINE_INFIX_BINARY_TRAIT(is_divisible, /); 98X operator/(X, X); 99X operator/(X, Y); 100STATIC_ASSERT((is_divisible<int>::value)); 101STATIC_ASSERT((is_divisible<int, long>::value)); 102STATIC_ASSERT((is_divisible<X>::value)); 103STATIC_ASSERT((!is_divisible<int*, int>::value)); 104STATIC_ASSERT((!is_divisible<int*>::value)); 105STATIC_ASSERT((is_divisible<X, Y>::value)); 106STATIC_ASSERT((!is_divisible<Y>::value)); 107STATIC_ASSERT((!is_divisible<int X::*>::value)); 108 109// has_remainder 110DEFINE_INFIX_BINARY_TRAIT(has_remainder, %); 111X operator%(X, X); 112X operator%(X, Y); 113STATIC_ASSERT((has_remainder<int>::value)); 114STATIC_ASSERT((has_remainder<int, long>::value)); 115STATIC_ASSERT((!has_remainder<float>::value)); 116STATIC_ASSERT((has_remainder<X>::value)); 117STATIC_ASSERT((!has_remainder<int*, int>::value)); 118STATIC_ASSERT((!has_remainder<int*>::value)); 119STATIC_ASSERT((has_remainder<X, Y>::value)); 120STATIC_ASSERT((!has_remainder<Y>::value)); 121STATIC_ASSERT((!has_remainder<int X::*>::value)); 122 123// has_xor 124DEFINE_INFIX_BINARY_TRAIT(has_xor, ^); 125X operator^(X, X); 126X operator^(X, Y); 127STATIC_ASSERT((has_xor<int>::value)); 128STATIC_ASSERT((has_xor<int, long>::value)); 129STATIC_ASSERT((!has_xor<float>::value)); 130STATIC_ASSERT((has_xor<X>::value)); 131STATIC_ASSERT((!has_xor<int*, int>::value)); 132STATIC_ASSERT((!has_xor<int*>::value)); 133STATIC_ASSERT((has_xor<X, Y>::value)); 134STATIC_ASSERT((!has_xor<Y>::value)); 135STATIC_ASSERT((!has_xor<int X::*>::value)); 136 137// has_bitand 138DEFINE_INFIX_BINARY_TRAIT(has_bitand, &); 139X operator&(X, X); 140X operator&(X, Y); 141STATIC_ASSERT((has_bitand<int>::value)); 142STATIC_ASSERT((has_bitand<int, long>::value)); 143STATIC_ASSERT((!has_bitand<float>::value)); 144STATIC_ASSERT((has_bitand<X>::value)); 145STATIC_ASSERT((!has_bitand<int*, int>::value)); 146STATIC_ASSERT((!has_bitand<int*>::value)); 147STATIC_ASSERT((has_bitand<X, Y>::value)); 148STATIC_ASSERT((!has_bitand<Y>::value)); 149STATIC_ASSERT((!has_bitand<int X::*>::value)); 150 151// has_bitor 152DEFINE_INFIX_BINARY_TRAIT(has_bitor, |); 153X operator|(X, X); 154X operator|(X, Y); 155STATIC_ASSERT((has_bitor<int>::value)); 156STATIC_ASSERT((has_bitor<int, long>::value)); 157STATIC_ASSERT((!has_bitor<float>::value)); 158STATIC_ASSERT((has_bitor<X>::value)); 159STATIC_ASSERT((!has_bitor<int*, int>::value)); 160STATIC_ASSERT((!has_bitor<int*>::value)); 161STATIC_ASSERT((has_bitor<X, Y>::value)); 162STATIC_ASSERT((!has_bitor<Y>::value)); 163STATIC_ASSERT((!has_bitor<int X::*>::value)); 164 165// has_left_shift 166DEFINE_INFIX_BINARY_TRAIT(has_left_shift, <<); 167X operator<<(X, X); 168X operator<<(X, Y); 169STATIC_ASSERT((has_left_shift<int>::value)); 170STATIC_ASSERT((has_left_shift<int, long>::value)); 171STATIC_ASSERT((!has_left_shift<float>::value)); 172STATIC_ASSERT((has_left_shift<X>::value)); 173STATIC_ASSERT((!has_left_shift<int*, int>::value)); 174STATIC_ASSERT((!has_left_shift<int*>::value)); 175STATIC_ASSERT((has_left_shift<X, Y>::value)); 176STATIC_ASSERT((!has_left_shift<Y>::value)); 177STATIC_ASSERT((!has_left_shift<int X::*>::value)); 178 179// has_right_shift 180DEFINE_INFIX_BINARY_TRAIT(has_right_shift, >>); 181X operator>>(X, X); 182X operator>>(X, Y); 183STATIC_ASSERT((has_right_shift<int>::value)); 184STATIC_ASSERT((has_right_shift<int, long>::value)); 185STATIC_ASSERT((!has_right_shift<float>::value)); 186STATIC_ASSERT((has_right_shift<X>::value)); 187STATIC_ASSERT((!has_right_shift<int*, int>::value)); 188STATIC_ASSERT((!has_right_shift<int*>::value)); 189STATIC_ASSERT((has_right_shift<X, Y>::value)); 190STATIC_ASSERT((!has_right_shift<Y>::value)); 191STATIC_ASSERT((!has_right_shift<int X::*>::value)); 192 193// can_subscript 194STATIC_ASSERT((can_subscript<int*, int>::value)); 195STATIC_ASSERT((can_subscript<int, int*>::value)); 196STATIC_ASSERT((can_subscript<int(&)[7], int>::value)); 197STATIC_ASSERT((can_subscript<int, int(&)[7]>::value)); 198STATIC_ASSERT((!can_subscript<X, Y>::value)); 199STATIC_ASSERT((can_subscript<Y, X>::value)); 200