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 37int 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