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 #ifndef TRANSPARENT_H 11 #define TRANSPARENT_H 12 13 #include "test_macros.h" 14 15 // testing transparent 16 #if TEST_STD_VER > 11 17 18 struct transparent_less 19 { 20 template <class T, class U> 21 constexpr auto operator()(T&& t, U&& u) const 22 noexcept(noexcept(std::forward<T>(t) < std::forward<U>(u))) 23 -> decltype (std::forward<T>(t) < std::forward<U>(u)) 24 { return std::forward<T>(t) < std::forward<U>(u); } 25 using is_transparent = void; // correct 26 }; 27 28 struct transparent_less_not_referenceable 29 { 30 template <class T, class U> 31 constexpr auto operator()(T&& t, U&& u) const 32 noexcept(noexcept(std::forward<T>(t) < std::forward<U>(u))) 33 -> decltype (std::forward<T>(t) < std::forward<U>(u)) 34 { return std::forward<T>(t) < std::forward<U>(u); } 35 using is_transparent = void () const &; // it's a type; a weird one, but a type 36 }; 37 38 struct transparent_less_no_type 39 { 40 template <class T, class U> 41 constexpr auto operator()(T&& t, U&& u) const 42 noexcept(noexcept(std::forward<T>(t) < std::forward<U>(u))) 43 -> decltype (std::forward<T>(t) < std::forward<U>(u)) 44 { return std::forward<T>(t) < std::forward<U>(u); } 45 private: 46 // using is_transparent = void; // error - should exist 47 }; 48 49 struct transparent_less_private 50 { 51 template <class T, class U> 52 constexpr auto operator()(T&& t, U&& u) const 53 noexcept(noexcept(std::forward<T>(t) < std::forward<U>(u))) 54 -> decltype (std::forward<T>(t) < std::forward<U>(u)) 55 { return std::forward<T>(t) < std::forward<U>(u); } 56 private: 57 using is_transparent = void; // error - should be accessible 58 }; 59 60 struct transparent_less_not_a_type 61 { 62 template <class T, class U> 63 constexpr auto operator()(T&& t, U&& u) const 64 noexcept(noexcept(std::forward<T>(t) < std::forward<U>(u))) 65 -> decltype (std::forward<T>(t) < std::forward<U>(u)) 66 { return std::forward<T>(t) < std::forward<U>(u); } 67 68 int is_transparent; // error - should be a type 69 }; 70 71 struct C2Int { // comparable to int 72 C2Int() : i_(0) {} 73 C2Int(int i): i_(i) {} 74 int get () const { return i_; } 75 private: 76 int i_; 77 }; 78 79 bool operator <(int rhs, const C2Int& lhs) { return rhs < lhs.get(); } 80 bool operator <(const C2Int& rhs, const C2Int& lhs) { return rhs.get() < lhs.get(); } 81 bool operator <(const C2Int& rhs, int lhs) { return rhs.get() < lhs; } 82 83 #endif 84 85 #endif // TRANSPARENT_H 86
