| 1 | /* |
|---|---|
| 2 | Copyright 2017-2018 Glen Joseph Fernandes |
| 3 | (glenjofe@gmail.com) |
| 4 | |
| 5 | Distributed under the Boost Software License, Version 1.0. |
| 6 | (http://www.boost.org/LICENSE_1_0.txt) |
| 7 | */ |
| 8 | #include <boost/core/pointer_traits.hpp> |
| 9 | #include <boost/core/lightweight_test.hpp> |
| 10 | |
| 11 | template<class T> |
| 12 | class P1 { |
| 13 | public: |
| 14 | explicit P1(T* p) |
| 15 | : p_(p) { } |
| 16 | |
| 17 | T* operator->() const BOOST_NOEXCEPT { |
| 18 | return p_; |
| 19 | } |
| 20 | |
| 21 | private: |
| 22 | T* p_; |
| 23 | }; |
| 24 | |
| 25 | template<class T> |
| 26 | class P2 { |
| 27 | public: |
| 28 | explicit P2(T* p) |
| 29 | : p_(p) { } |
| 30 | |
| 31 | P1<T> operator->() const BOOST_NOEXCEPT { |
| 32 | return p_; |
| 33 | } |
| 34 | |
| 35 | private: |
| 36 | P1<T> p_; |
| 37 | }; |
| 38 | |
| 39 | #if !defined(BOOST_NO_CXX14_RETURN_TYPE_DEDUCTION) |
| 40 | template<class T> |
| 41 | class P3 { |
| 42 | public: |
| 43 | explicit P3(T* p) |
| 44 | : p_(p) { } |
| 45 | |
| 46 | T* get() const BOOST_NOEXCEPT { |
| 47 | return p_; |
| 48 | } |
| 49 | |
| 50 | private: |
| 51 | T* p_; |
| 52 | }; |
| 53 | |
| 54 | namespace boost { |
| 55 | |
| 56 | template<class T> |
| 57 | struct pointer_traits<P3<T> > { |
| 58 | static T* to_address(const P3<T>& p) BOOST_NOEXCEPT { |
| 59 | return p.get(); |
| 60 | } |
| 61 | }; |
| 62 | |
| 63 | } /* boost */ |
| 64 | |
| 65 | template<class T> |
| 66 | class P4 { |
| 67 | public: |
| 68 | explicit P4(T* p) |
| 69 | : p_(p) { } |
| 70 | |
| 71 | T* operator->() const BOOST_NOEXCEPT { |
| 72 | return 0; |
| 73 | } |
| 74 | |
| 75 | T* get() const BOOST_NOEXCEPT { |
| 76 | return p_; |
| 77 | } |
| 78 | |
| 79 | private: |
| 80 | int* p_; |
| 81 | }; |
| 82 | |
| 83 | namespace boost { |
| 84 | |
| 85 | template<class T> |
| 86 | struct pointer_traits<P4<T> > { |
| 87 | static T* to_address(const P4<T>& p) BOOST_NOEXCEPT { |
| 88 | return p.get(); |
| 89 | } |
| 90 | }; |
| 91 | |
| 92 | } /* boost */ |
| 93 | #endif |
| 94 | |
| 95 | int main() |
| 96 | { |
| 97 | int i = 0; |
| 98 | BOOST_TEST(boost::to_address(&i) == &i); |
| 99 | int* p = &i; |
| 100 | BOOST_TEST(boost::to_address(p) == &i); |
| 101 | P1<int> p1(&i); |
| 102 | BOOST_TEST(boost::to_address(p1) == &i); |
| 103 | P2<int> p2(&i); |
| 104 | BOOST_TEST(boost::to_address(p2) == &i); |
| 105 | #if !defined(BOOST_NO_CXX14_RETURN_TYPE_DEDUCTION) |
| 106 | P3<int> p3(&i); |
| 107 | BOOST_TEST(boost::to_address(p3) == &i); |
| 108 | P4<int> p4(&i); |
| 109 | BOOST_TEST(boost::to_address(p4) == &i); |
| 110 | #endif |
| 111 | return boost::report_errors(); |
| 112 | } |
| 113 |