1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <functional> 11 12 // template <class T> 13 // struct hash 14 // : public unary_function<T, size_t> 15 // { 16 // size_t operator()(T val) const; 17 // }; 18 19 // Not very portable 20 21 #include <functional> 22 #include <cassert> 23 #include <type_traits> 24 #include <limits> 25 #include <cmath> 26 27 template <class T> 28 void 29 test() 30 { 31 static_assert((std::is_base_of<std::unary_function<T, std::size_t>, 32 std::hash<T> >::value), ""); 33 std::hash<T> h; 34 std::size_t t0 = h(0.); 35 std::size_t tn0 = h(-0.); 36 std::size_t tp1 = h(0.1); 37 std::size_t t1 = h(1); 38 std::size_t tn1 = h(-1); 39 std::size_t pinf = h(INFINITY); 40 std::size_t ninf = h(-INFINITY); 41 assert(t0 == tn0); 42 assert(t0 != tp1); 43 assert(t0 != t1); 44 assert(t0 != tn1); 45 assert(t0 != pinf); 46 assert(t0 != ninf); 47 48 assert(tp1 != t1); 49 assert(tp1 != tn1); 50 assert(tp1 != pinf); 51 assert(tp1 != ninf); 52 53 assert(t1 != tn1); 54 assert(t1 != pinf); 55 assert(t1 != ninf); 56 57 assert(tn1 != pinf); 58 assert(tn1 != ninf); 59 60 assert(pinf != ninf); 61 } 62 63 int main() 64 { 65 test<float>(); 66 test<double>(); 67 test<long double>(); 68 } 69
