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; 20 // bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const; 21 // bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const; 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; 30 // bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const; 31 // bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const; 32 // }; 33 34 #include <memory> 35 #include <cassert> 36 37 int main() 38 { 39 const std::shared_ptr<int> p1(new int); 40 const std::shared_ptr<int> p2 = p1; 41 const std::shared_ptr<int> p3(new int); 42 const std::weak_ptr<int> w1(p1); 43 const std::weak_ptr<int> w2(p2); 44 const std::weak_ptr<int> w3(p3); 45 46 { 47 typedef std::owner_less<std::shared_ptr<int> > CS; 48 CS cs; 49 50 assert(!cs(p1, p2)); 51 assert(!cs(p2, p1)); 52 assert(cs(p1 ,p3) || cs(p3, p1)); 53 assert(cs(p3, p1) == cs(p3, p2)); 54 55 assert(!cs(p1, w2)); 56 assert(!cs(p2, w1)); 57 assert(cs(p1, w3) || cs(p3, w1)); 58 assert(cs(p3, w1) == cs(p3, w2)); 59 } 60 { 61 typedef std::owner_less<std::weak_ptr<int> > CS; 62 CS cs; 63 64 assert(!cs(w1, w2)); 65 assert(!cs(w2, w1)); 66 assert(cs(w1, w3) || cs(w3, w1)); 67 assert(cs(w3, w1) == cs(w3, w2)); 68 69 assert(!cs(w1, p2)); 70 assert(!cs(w2, p1)); 71 assert(cs(w1, p3) || cs(w3, p1)); 72 assert(cs(w3, p1) == cs(w3, p2)); 73 } 74 } 75
