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 <string> 22 #include <cassert> 23 #include <type_traits> 24 25 #include "test_macros.h" 26 27 template <class T> 28 void test()29test() 30 { 31 typedef std::hash<T> H; 32 static_assert((std::is_same<typename H::argument_type, T>::value), "" ); 33 static_assert((std::is_same<typename H::result_type, std::size_t>::value), "" ); 34 ASSERT_NOEXCEPT(H()(T())); 35 36 H h; 37 std::string g1 = "1234567890"; 38 std::string g2 = "1234567891"; 39 T s1(g1.begin(), g1.end()); 40 T s2(g2.begin(), g2.end()); 41 assert(h(s1) != h(s2)); 42 } 43 main()44int main() 45 { 46 test<std::string>(); 47 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L 48 test<std::u8string>(); 49 #endif 50 #ifndef _LIBCPP_HAS_NO_UNICODE_CHARS 51 test<std::u16string>(); 52 test<std::u32string>(); 53 #endif // _LIBCPP_HAS_NO_UNICODE_CHARS 54 test<std::wstring>(); 55 } 56