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 // <memory> 11 12 // template <class T> struct owner_less; 13 // 14 // template <class T> 15 // struct owner_less<shared_ptr<T> > 16 // : binary_function<shared_ptr<T>, shared_ptr<T>, bool> 17 // { 18 // typedef bool result_type; 19 // bool operator()(shared_ptr<T> const&, shared_ptr<T> const&) const noexcept; 20 // bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const noexcept; 21 // bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const noexcept; 22 // }; 23 // 24 // template <class T> 25 // struct owner_less<weak_ptr<T> > 26 // : binary_function<weak_ptr<T>, weak_ptr<T>, bool> 27 // { 28 // typedef bool result_type; 29 // bool operator()(weak_ptr<T> const&, weak_ptr<T> const&) const noexcept; 30 // bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const noexcept; 31 // bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const noexcept; 32 // }; 33 // 34 // Added in C++17 35 // template<> struct owner_less<void> 36 // { 37 // template<class T, class U> 38 // bool operator()(shared_ptr<T> const&, shared_ptr<U> const&) const noexcept; 39 // template<class T, class U> 40 // bool operator()(shared_ptr<T> const&, weak_ptr<U> const&) const noexcept; 41 // template<class T, class U> 42 // bool operator()(weak_ptr<T> const&, shared_ptr<U> const&) const noexcept; 43 // template<class T, class U> 44 // bool operator()(weak_ptr<T> const&, weak_ptr<U> const&) const noexcept; 45 // 46 // typedef unspecified is_transparent; 47 // }; 48 49 #include <memory> 50 #include <cassert> 51 #include <set> 52 #include "test_macros.h" 53 54 struct X {}; 55 56 int main() 57 { 58 const std::shared_ptr<int> p1(new int); 59 const std::shared_ptr<int> p2 = p1; 60 const std::shared_ptr<int> p3(new int); 61 const std::weak_ptr<int> w1(p1); 62 const std::weak_ptr<int> w2(p2); 63 const std::weak_ptr<int> w3(p3); 64 65 { 66 typedef std::owner_less<std::shared_ptr<int> > CS; 67 CS cs; 68 69 static_assert((std::is_same<std::shared_ptr<int>, CS::first_argument_type>::value), "" ); 70 static_assert((std::is_same<std::shared_ptr<int>, CS::second_argument_type>::value), "" ); 71 static_assert((std::is_same<bool, CS::result_type>::value), "" ); 72 73 assert(!cs(p1, p2)); 74 assert(!cs(p2, p1)); 75 assert(cs(p1 ,p3) || cs(p3, p1)); 76 assert(cs(p3, p1) == cs(p3, p2)); 77 ASSERT_NOEXCEPT(cs(p1, p1)); 78 79 assert(!cs(p1, w2)); 80 assert(!cs(p2, w1)); 81 assert(cs(p1, w3) || cs(p3, w1)); 82 assert(cs(p3, w1) == cs(p3, w2)); 83 ASSERT_NOEXCEPT(cs(p1, w1)); 84 ASSERT_NOEXCEPT(cs(w1, p1)); 85 } 86 { 87 typedef std::owner_less<std::weak_ptr<int> > CS; 88 CS cs; 89 90 static_assert((std::is_same<std::weak_ptr<int>, CS::first_argument_type>::value), "" ); 91 static_assert((std::is_same<std::weak_ptr<int>, CS::second_argument_type>::value), "" ); 92 static_assert((std::is_same<bool, CS::result_type>::value), "" ); 93 94 assert(!cs(w1, w2)); 95 assert(!cs(w2, w1)); 96 assert(cs(w1, w3) || cs(w3, w1)); 97 assert(cs(w3, w1) == cs(w3, w2)); 98 ASSERT_NOEXCEPT(cs(w1, w1)); 99 100 assert(!cs(w1, p2)); 101 assert(!cs(w2, p1)); 102 assert(cs(w1, p3) || cs(w3, p1)); 103 assert(cs(w3, p1) == cs(w3, p2)); 104 ASSERT_NOEXCEPT(cs(w1, p1)); 105 ASSERT_NOEXCEPT(cs(p1, w1)); 106 } 107 #if TEST_STD_VER > 14 108 { 109 std::shared_ptr<int> sp1; 110 std::shared_ptr<void> sp2; 111 std::shared_ptr<long> sp3; 112 std::weak_ptr<int> wp1; 113 114 std::owner_less<> cmp; 115 cmp(sp1, sp2); 116 cmp(sp1, wp1); 117 cmp(sp1, sp3); 118 cmp(wp1, sp1); 119 cmp(wp1, wp1); 120 ASSERT_NOEXCEPT(cmp(sp1, sp1)); 121 ASSERT_NOEXCEPT(cmp(sp1, wp1)); 122 ASSERT_NOEXCEPT(cmp(wp1, sp1)); 123 ASSERT_NOEXCEPT(cmp(wp1, wp1)); 124 } 125 { 126 // test heterogeneous lookups 127 std::set<std::shared_ptr<X>, std::owner_less<>> s; 128 std::shared_ptr<void> vp; 129 s.find(vp); 130 } 131 #endif 132 } 133
