| // (C) Copyright Steve Cleary, Beman Dawes, Howard Hinnant & John Maddock 2000. |
| // Use, modification and distribution are subject to the Boost Software License, |
| // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
| // http://www.boost.org/LICENSE_1_0.txt). |
| // |
| // See http://www.boost.org/libs/utility for most recent version including documentation. |
| |
| // compressed_pair: pair that "compresses" empty members |
| // (see libs/utility/compressed_pair.htm) |
| // |
| // JM changes 25 Jan 2004: |
| // For the case where T1 == T2 and both are empty, then first() and second() |
| // should return different objects. |
| // JM changes 25 Jan 2000: |
| // Removed default arguments from compressed_pair_switch to get |
| // C++ Builder 4 to accept them |
| // rewriten swap to get gcc and C++ builder to compile. |
| // added partial specialisations for case T1 == T2 to avoid duplicate constructor defs. |
| |
| #ifndef BOOST_DETAIL_COMPRESSED_PAIR_HPP |
| #define BOOST_DETAIL_COMPRESSED_PAIR_HPP |
| |
| #include <algorithm> |
| |
| #include <boost/type_traits/remove_cv.hpp> |
| #include <boost/type_traits/is_empty.hpp> |
| #include <boost/type_traits/is_same.hpp> |
| #include <boost/call_traits.hpp> |
| |
| #ifdef BOOST_MSVC |
| # pragma warning(push) |
| # pragma warning(disable:4512) |
| #endif |
| namespace boost |
| { |
| |
| template <class T1, class T2> |
| class compressed_pair; |
| |
| |
| // compressed_pair |
| |
| namespace details |
| { |
| // JM altered 26 Jan 2000: |
| template <class T1, class T2, bool IsSame, bool FirstEmpty, bool SecondEmpty> |
| struct compressed_pair_switch; |
| |
| template <class T1, class T2> |
| struct compressed_pair_switch<T1, T2, false, false, false> |
| {static const int value = 0;}; |
| |
| template <class T1, class T2> |
| struct compressed_pair_switch<T1, T2, false, true, true> |
| {static const int value = 3;}; |
| |
| template <class T1, class T2> |
| struct compressed_pair_switch<T1, T2, false, true, false> |
| {static const int value = 1;}; |
| |
| template <class T1, class T2> |
| struct compressed_pair_switch<T1, T2, false, false, true> |
| {static const int value = 2;}; |
| |
| template <class T1, class T2> |
| struct compressed_pair_switch<T1, T2, true, true, true> |
| {static const int value = 4;}; |
| |
| template <class T1, class T2> |
| struct compressed_pair_switch<T1, T2, true, false, false> |
| {static const int value = 5;}; |
| |
| template <class T1, class T2, int Version> class compressed_pair_imp; |
| |
| #ifdef __GNUC__ |
| // workaround for GCC (JM): |
| using std::swap; |
| #endif |
| // |
| // can't call unqualified swap from within classname::swap |
| // as Koenig lookup rules will find only the classname::swap |
| // member function not the global declaration, so use cp_swap |
| // as a forwarding function (JM): |
| template <typename T> |
| inline void cp_swap(T& t1, T& t2) |
| { |
| #ifndef __GNUC__ |
| using std::swap; |
| #endif |
| swap(t1, t2); |
| } |
| |
| // 0 derive from neither |
| |
| template <class T1, class T2> |
| class compressed_pair_imp<T1, T2, 0> |
| { |
| public: |
| typedef T1 first_type; |
| typedef T2 second_type; |
| typedef typename call_traits<first_type>::param_type first_param_type; |
| typedef typename call_traits<second_type>::param_type second_param_type; |
| typedef typename call_traits<first_type>::reference first_reference; |
| typedef typename call_traits<second_type>::reference second_reference; |
| typedef typename call_traits<first_type>::const_reference first_const_reference; |
| typedef typename call_traits<second_type>::const_reference second_const_reference; |
| |
| compressed_pair_imp() {} |
| |
| compressed_pair_imp(first_param_type x, second_param_type y) |
| : first_(x), second_(y) {} |
| |
| compressed_pair_imp(first_param_type x) |
| : first_(x) {} |
| |
| compressed_pair_imp(second_param_type y) |
| : second_(y) {} |
| |
| first_reference first() {return first_;} |
| first_const_reference first() const {return first_;} |
| |
| second_reference second() {return second_;} |
| second_const_reference second() const {return second_;} |
| |
| void swap(::boost::compressed_pair<T1, T2>& y) |
| { |
| cp_swap(first_, y.first()); |
| cp_swap(second_, y.second()); |
| } |
| private: |
| first_type first_; |
| second_type second_; |
| }; |
| |
| // 1 derive from T1 |
| |
| template <class T1, class T2> |
| class compressed_pair_imp<T1, T2, 1> |
| : protected ::boost::remove_cv<T1>::type |
| { |
| public: |
| typedef T1 first_type; |
| typedef T2 second_type; |
| typedef typename call_traits<first_type>::param_type first_param_type; |
| typedef typename call_traits<second_type>::param_type second_param_type; |
| typedef typename call_traits<first_type>::reference first_reference; |
| typedef typename call_traits<second_type>::reference second_reference; |
| typedef typename call_traits<first_type>::const_reference first_const_reference; |
| typedef typename call_traits<second_type>::const_reference second_const_reference; |
| |
| compressed_pair_imp() {} |
| |
| compressed_pair_imp(first_param_type x, second_param_type y) |
| : first_type(x), second_(y) {} |
| |
| compressed_pair_imp(first_param_type x) |
| : first_type(x) {} |
| |
| compressed_pair_imp(second_param_type y) |
| : second_(y) {} |
| |
| first_reference first() {return *this;} |
| first_const_reference first() const {return *this;} |
| |
| second_reference second() {return second_;} |
| second_const_reference second() const {return second_;} |
| |
| void swap(::boost::compressed_pair<T1,T2>& y) |
| { |
| // no need to swap empty base class: |
| cp_swap(second_, y.second()); |
| } |
| private: |
| second_type second_; |
| }; |
| |
| // 2 derive from T2 |
| |
| template <class T1, class T2> |
| class compressed_pair_imp<T1, T2, 2> |
| : protected ::boost::remove_cv<T2>::type |
| { |
| public: |
| typedef T1 first_type; |
| typedef T2 second_type; |
| typedef typename call_traits<first_type>::param_type first_param_type; |
| typedef typename call_traits<second_type>::param_type second_param_type; |
| typedef typename call_traits<first_type>::reference first_reference; |
| typedef typename call_traits<second_type>::reference second_reference; |
| typedef typename call_traits<first_type>::const_reference first_const_reference; |
| typedef typename call_traits<second_type>::const_reference second_const_reference; |
| |
| compressed_pair_imp() {} |
| |
| compressed_pair_imp(first_param_type x, second_param_type y) |
| : second_type(y), first_(x) {} |
| |
| compressed_pair_imp(first_param_type x) |
| : first_(x) {} |
| |
| compressed_pair_imp(second_param_type y) |
| : second_type(y) {} |
| |
| first_reference first() {return first_;} |
| first_const_reference first() const {return first_;} |
| |
| second_reference second() {return *this;} |
| second_const_reference second() const {return *this;} |
| |
| void swap(::boost::compressed_pair<T1,T2>& y) |
| { |
| // no need to swap empty base class: |
| cp_swap(first_, y.first()); |
| } |
| |
| private: |
| first_type first_; |
| }; |
| |
| // 3 derive from T1 and T2 |
| |
| template <class T1, class T2> |
| class compressed_pair_imp<T1, T2, 3> |
| : protected ::boost::remove_cv<T1>::type, |
| protected ::boost::remove_cv<T2>::type |
| { |
| public: |
| typedef T1 first_type; |
| typedef T2 second_type; |
| typedef typename call_traits<first_type>::param_type first_param_type; |
| typedef typename call_traits<second_type>::param_type second_param_type; |
| typedef typename call_traits<first_type>::reference first_reference; |
| typedef typename call_traits<second_type>::reference second_reference; |
| typedef typename call_traits<first_type>::const_reference first_const_reference; |
| typedef typename call_traits<second_type>::const_reference second_const_reference; |
| |
| compressed_pair_imp() {} |
| |
| compressed_pair_imp(first_param_type x, second_param_type y) |
| : first_type(x), second_type(y) {} |
| |
| compressed_pair_imp(first_param_type x) |
| : first_type(x) {} |
| |
| compressed_pair_imp(second_param_type y) |
| : second_type(y) {} |
| |
| first_reference first() {return *this;} |
| first_const_reference first() const {return *this;} |
| |
| second_reference second() {return *this;} |
| second_const_reference second() const {return *this;} |
| // |
| // no need to swap empty bases: |
| void swap(::boost::compressed_pair<T1,T2>&) {} |
| }; |
| |
| // JM |
| // 4 T1 == T2, T1 and T2 both empty |
| // Originally this did not store an instance of T2 at all |
| // but that led to problems beause it meant &x.first() == &x.second() |
| // which is not true for any other kind of pair, so now we store an instance |
| // of T2 just in case the user is relying on first() and second() returning |
| // different objects (albeit both empty). |
| template <class T1, class T2> |
| class compressed_pair_imp<T1, T2, 4> |
| : protected ::boost::remove_cv<T1>::type |
| { |
| public: |
| typedef T1 first_type; |
| typedef T2 second_type; |
| typedef typename call_traits<first_type>::param_type first_param_type; |
| typedef typename call_traits<second_type>::param_type second_param_type; |
| typedef typename call_traits<first_type>::reference first_reference; |
| typedef typename call_traits<second_type>::reference second_reference; |
| typedef typename call_traits<first_type>::const_reference first_const_reference; |
| typedef typename call_traits<second_type>::const_reference second_const_reference; |
| |
| compressed_pair_imp() {} |
| |
| compressed_pair_imp(first_param_type x, second_param_type y) |
| : first_type(x), m_second(y) {} |
| |
| compressed_pair_imp(first_param_type x) |
| : first_type(x), m_second(x) {} |
| |
| first_reference first() {return *this;} |
| first_const_reference first() const {return *this;} |
| |
| second_reference second() {return m_second;} |
| second_const_reference second() const {return m_second;} |
| |
| void swap(::boost::compressed_pair<T1,T2>&) {} |
| private: |
| T2 m_second; |
| }; |
| |
| // 5 T1 == T2 and are not empty: //JM |
| |
| template <class T1, class T2> |
| class compressed_pair_imp<T1, T2, 5> |
| { |
| public: |
| typedef T1 first_type; |
| typedef T2 second_type; |
| typedef typename call_traits<first_type>::param_type first_param_type; |
| typedef typename call_traits<second_type>::param_type second_param_type; |
| typedef typename call_traits<first_type>::reference first_reference; |
| typedef typename call_traits<second_type>::reference second_reference; |
| typedef typename call_traits<first_type>::const_reference first_const_reference; |
| typedef typename call_traits<second_type>::const_reference second_const_reference; |
| |
| compressed_pair_imp() {} |
| |
| compressed_pair_imp(first_param_type x, second_param_type y) |
| : first_(x), second_(y) {} |
| |
| compressed_pair_imp(first_param_type x) |
| : first_(x), second_(x) {} |
| |
| first_reference first() {return first_;} |
| first_const_reference first() const {return first_;} |
| |
| second_reference second() {return second_;} |
| second_const_reference second() const {return second_;} |
| |
| void swap(::boost::compressed_pair<T1, T2>& y) |
| { |
| cp_swap(first_, y.first()); |
| cp_swap(second_, y.second()); |
| } |
| private: |
| first_type first_; |
| second_type second_; |
| }; |
| |
| } // details |
| |
| template <class T1, class T2> |
| class compressed_pair |
| : private ::boost::details::compressed_pair_imp<T1, T2, |
| ::boost::details::compressed_pair_switch< |
| T1, |
| T2, |
| ::boost::is_same<typename remove_cv<T1>::type, typename remove_cv<T2>::type>::value, |
| ::boost::is_empty<T1>::value, |
| ::boost::is_empty<T2>::value>::value> |
| { |
| private: |
| typedef details::compressed_pair_imp<T1, T2, |
| ::boost::details::compressed_pair_switch< |
| T1, |
| T2, |
| ::boost::is_same<typename remove_cv<T1>::type, typename remove_cv<T2>::type>::value, |
| ::boost::is_empty<T1>::value, |
| ::boost::is_empty<T2>::value>::value> base; |
| public: |
| typedef T1 first_type; |
| typedef T2 second_type; |
| typedef typename call_traits<first_type>::param_type first_param_type; |
| typedef typename call_traits<second_type>::param_type second_param_type; |
| typedef typename call_traits<first_type>::reference first_reference; |
| typedef typename call_traits<second_type>::reference second_reference; |
| typedef typename call_traits<first_type>::const_reference first_const_reference; |
| typedef typename call_traits<second_type>::const_reference second_const_reference; |
| |
| compressed_pair() : base() {} |
| compressed_pair(first_param_type x, second_param_type y) : base(x, y) {} |
| explicit compressed_pair(first_param_type x) : base(x) {} |
| explicit compressed_pair(second_param_type y) : base(y) {} |
| |
| first_reference first() {return base::first();} |
| first_const_reference first() const {return base::first();} |
| |
| second_reference second() {return base::second();} |
| second_const_reference second() const {return base::second();} |
| |
| void swap(compressed_pair& y) { base::swap(y); } |
| }; |
| |
| // JM |
| // Partial specialisation for case where T1 == T2: |
| // |
| template <class T> |
| class compressed_pair<T, T> |
| : private details::compressed_pair_imp<T, T, |
| ::boost::details::compressed_pair_switch< |
| T, |
| T, |
| ::boost::is_same<typename remove_cv<T>::type, typename remove_cv<T>::type>::value, |
| ::boost::is_empty<T>::value, |
| ::boost::is_empty<T>::value>::value> |
| { |
| private: |
| typedef details::compressed_pair_imp<T, T, |
| ::boost::details::compressed_pair_switch< |
| T, |
| T, |
| ::boost::is_same<typename remove_cv<T>::type, typename remove_cv<T>::type>::value, |
| ::boost::is_empty<T>::value, |
| ::boost::is_empty<T>::value>::value> base; |
| public: |
| typedef T first_type; |
| typedef T second_type; |
| typedef typename call_traits<first_type>::param_type first_param_type; |
| typedef typename call_traits<second_type>::param_type second_param_type; |
| typedef typename call_traits<first_type>::reference first_reference; |
| typedef typename call_traits<second_type>::reference second_reference; |
| typedef typename call_traits<first_type>::const_reference first_const_reference; |
| typedef typename call_traits<second_type>::const_reference second_const_reference; |
| |
| compressed_pair() : base() {} |
| compressed_pair(first_param_type x, second_param_type y) : base(x, y) {} |
| #if !(defined(__SUNPRO_CC) && (__SUNPRO_CC <= 0x530)) |
| explicit |
| #endif |
| compressed_pair(first_param_type x) : base(x) {} |
| |
| first_reference first() {return base::first();} |
| first_const_reference first() const {return base::first();} |
| |
| second_reference second() {return base::second();} |
| second_const_reference second() const {return base::second();} |
| |
| void swap(::boost::compressed_pair<T,T>& y) { base::swap(y); } |
| }; |
| |
| template <class T1, class T2> |
| inline |
| void |
| swap(compressed_pair<T1, T2>& x, compressed_pair<T1, T2>& y) |
| { |
| x.swap(y); |
| } |
| |
| } // boost |
| |
| #ifdef BOOST_MSVC |
| # pragma warning(pop) |
| #endif |
| |
| #endif // BOOST_DETAIL_COMPRESSED_PAIR_HPP |
| |