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-rw-r--r--boost/core/pointer_traits.hpp258
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diff --git a/boost/core/pointer_traits.hpp b/boost/core/pointer_traits.hpp
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+/*
+Copyright 2017 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#ifndef BOOST_CORE_POINTER_TRAITS_HPP
+#define BOOST_CORE_POINTER_TRAITS_HPP
+
+#include <boost/config.hpp>
+#if !defined(BOOST_NO_CXX11_POINTER_TRAITS)
+#include <memory>
+#else
+#include <boost/core/addressof.hpp>
+#endif
+
+namespace boost {
+
+template<class T>
+struct pointer_traits;
+
+namespace detail {
+
+template<class U>
+inline typename boost::pointer_traits<U>::element_type*
+ptr_traits_address(const U& v) BOOST_NOEXCEPT
+{
+ return boost::pointer_traits<U>::to_address(v);
+}
+
+} /* detail */
+
+#if !defined(BOOST_NO_CXX11_POINTER_TRAITS)
+template<class T>
+struct pointer_traits
+ : std::pointer_traits<T> {
+ template<class U>
+ struct rebind_to {
+ typedef typename std::pointer_traits<T>::template rebind<U> type;
+ };
+ static typename std::pointer_traits<T>::element_type*
+ to_address(const T& v) BOOST_NOEXCEPT {
+ return detail::ptr_traits_address(v.operator->());
+ }
+};
+
+template<class T>
+struct pointer_traits<T*>
+ : std::pointer_traits<T*> {
+ template<class U>
+ struct rebind_to {
+ typedef U* type;
+ };
+ static T* to_address(T* v) BOOST_NOEXCEPT {
+ return v;
+ }
+};
+#else
+namespace detail {
+
+struct ptr_traits_none { char first, second; };
+
+template<class T>
+struct ptr_traits_has_element {
+private:
+ template<class U>
+ static ptr_traits_none call(...);
+ template<class U>
+ static char call(typename U::element_type* = 0);
+public:
+ static const bool value = sizeof(call<T>(0)) == 1;
+};
+
+template<class T>
+struct ptr_traits_first;
+
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+template<template<class, class...> class T, class U, class... Args>
+struct ptr_traits_first<T<U, Args...> > {
+ typedef U type;
+};
+#else
+template<template<class> class T, class U>
+struct ptr_traits_first<T<U> > {
+ typedef U type;
+};
+
+template<template<class, class> class T, class U1, class U2>
+struct ptr_traits_first<T<U1, U2> > {
+ typedef U1 type;
+};
+
+template<template<class, class, class> class T, class U1, class U2, class U3>
+struct ptr_traits_first<T<U1, U2, U3> > {
+ typedef U1 type;
+};
+#endif
+
+template<class T, bool = ptr_traits_has_element<T>::value>
+struct ptr_traits_element {
+ typedef typename T::element_type type;
+};
+
+template<class T>
+struct ptr_traits_element<T, false> {
+ typedef typename ptr_traits_first<T>::type type;
+};
+
+template<class T>
+struct ptr_traits_has_difference {
+private:
+ template<class U>
+ static ptr_traits_none call(...);
+ template<class U>
+ static char call(typename U::difference_type* = 0);
+public:
+ static const bool value = sizeof(call<T>(0)) == 1;
+};
+
+template<class T, bool = ptr_traits_has_difference<T>::value>
+struct ptr_traits_difference {
+ typedef typename T::difference_type type;
+};
+
+template<class T>
+struct ptr_traits_difference<T, false> {
+ typedef std::ptrdiff_t type;
+};
+
+template<class T, class V>
+struct ptr_traits_has_rebind {
+private:
+ template<class U>
+ static ptr_traits_none call(...);
+ template<class U>
+ static char call(typename U::template rebind<V>* = 0);
+public:
+ static const bool value = sizeof(call<T>(0)) == 1;
+};
+
+template<class T, class V>
+struct ptr_traits_rebind_to;
+
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+template<template<class, class...> class T, class U, class... Args, class V>
+struct ptr_traits_rebind_to<T<U, Args...>, V> {
+ typedef T<V, Args...> type;
+};
+#else
+template<template<class> class T, class U, class V>
+struct ptr_traits_rebind_to<T<U>, V> {
+ typedef T<V> type;
+};
+
+template<template<class, class> class T, class U1, class U2, class V>
+struct ptr_traits_rebind_to<T<U1, U2>, V> {
+ typedef T<V, U2> type;
+};
+
+template<template<class, class, class> class T,
+ class U1, class U2, class U3, class V>
+struct ptr_traits_rebind_to<T<U1, U2, U3>, V> {
+ typedef T<V, U2, U3> type;
+};
+#endif
+
+#if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES)
+template<class T, class U, bool = ptr_traits_has_rebind<T, U>::value>
+struct ptr_traits_rebind {
+ typedef typename T::template rebind<U> type;
+};
+
+template<class T, class U>
+struct ptr_traits_rebind<T, U, false> {
+ typedef typename ptr_traits_rebind_to<T, U>::type type;
+};
+#else
+template<class T, class U>
+struct ptr_traits_rebind {
+ typedef typename ptr_traits_rebind_to<T, U>::type type;
+};
+#endif
+
+template<class T>
+struct ptr_traits_value {
+ typedef T type;
+};
+
+template<>
+struct ptr_traits_value<void> {
+ typedef struct { } type;
+};
+
+} /* detail */
+
+template<class T>
+struct pointer_traits {
+ typedef T pointer;
+ typedef typename detail::ptr_traits_element<T>::type element_type;
+ typedef typename detail::ptr_traits_difference<T>::type difference_type;
+ template<class U>
+ struct rebind_to {
+ typedef typename detail::ptr_traits_rebind<T, U>::type type;
+ };
+#if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES)
+ template<class U>
+ using rebind = typename detail::ptr_traits_rebind<T, U>::type;
+#endif
+ static pointer
+ pointer_to(typename detail::ptr_traits_value<element_type>::type& v) {
+ return pointer::pointer_to(v);
+ }
+ static element_type* to_address(const pointer& v) BOOST_NOEXCEPT {
+ return detail::ptr_traits_address(v.operator->());
+ }
+};
+
+template<class T>
+struct pointer_traits<T*> {
+ typedef T* pointer;
+ typedef T element_type;
+ typedef std::ptrdiff_t difference_type;
+ template<class U>
+ struct rebind_to {
+ typedef U* type;
+ };
+#if !defined(BOOST_NO_CXX11_TEMPLATE_ALIASES)
+ template<class U>
+ using rebind = U*;
+#endif
+ static T*
+ pointer_to(typename detail::ptr_traits_value<T>::type& v) BOOST_NOEXCEPT {
+ return addressof(v);
+ }
+ static T* to_address(T* v) BOOST_NOEXCEPT {
+ return v;
+ }
+};
+#endif
+
+template<class T>
+inline typename pointer_traits<T>::element_type*
+to_address(const T& v) BOOST_NOEXCEPT
+{
+ return pointer_traits<T>::to_address(v);
+}
+
+template<class T>
+inline T*
+to_address(T* v) BOOST_NOEXCEPT
+{
+ return v;
+}
+
+} /* boost */
+
+#endif
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