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/*
Copyright 2017-2018 Glen Joseph Fernandes
(glenjofe@gmail.com)
Distributed under the Boost Software License, Version 1.0.
(http://www.boost.org/LICENSE_1_0.txt)
*/
#include <boost/core/pointer_traits.hpp>
#include <boost/core/lightweight_test.hpp>
template<class T>
class P1 {
public:
explicit P1(T* p)
: p_(p) { }
T* operator->() const BOOST_NOEXCEPT {
return p_;
}
private:
T* p_;
};
template<class T>
class P2 {
public:
explicit P2(T* p)
: p_(p) { }
P1<T> operator->() const BOOST_NOEXCEPT {
return p_;
}
private:
P1<T> p_;
};
#if !defined(BOOST_NO_CXX14_RETURN_TYPE_DEDUCTION)
template<class T>
class P3 {
public:
explicit P3(T* p)
: p_(p) { }
T* get() const BOOST_NOEXCEPT {
return p_;
}
private:
T* p_;
};
namespace boost {
template<class T>
struct pointer_traits<P3<T> > {
static T* to_address(const P3<T>& p) BOOST_NOEXCEPT {
return p.get();
}
};
} /* boost */
template<class T>
class P4 {
public:
explicit P4(T* p)
: p_(p) { }
T* operator->() const BOOST_NOEXCEPT {
return 0;
}
T* get() const BOOST_NOEXCEPT {
return p_;
}
private:
int* p_;
};
namespace boost {
template<class T>
struct pointer_traits<P4<T> > {
static T* to_address(const P4<T>& p) BOOST_NOEXCEPT {
return p.get();
}
};
} /* boost */
#endif
int main()
{
int i = 0;
BOOST_TEST(boost::to_address(&i) == &i);
int* p = &i;
BOOST_TEST(boost::to_address(p) == &i);
P1<int> p1(&i);
BOOST_TEST(boost::to_address(p1) == &i);
P2<int> p2(&i);
BOOST_TEST(boost::to_address(p2) == &i);
#if !defined(BOOST_NO_CXX14_RETURN_TYPE_DEDUCTION)
P3<int> p3(&i);
BOOST_TEST(boost::to_address(p3) == &i);
P4<int> p4(&i);
BOOST_TEST(boost::to_address(p4) == &i);
#endif
return boost::report_errors();
}
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