williamr@2: /* Copyright 2003-2005 Joaquín M López Muñoz.
williamr@2:  * Distributed under the Boost Software License, Version 1.0.
williamr@2:  * (See accompanying file LICENSE_1_0.txt or copy at
williamr@2:  * http://www.boost.org/LICENSE_1_0.txt)
williamr@2:  *
williamr@2:  * See http://www.boost.org/libs/multi_index for library home page.
williamr@2:  */
williamr@2: 
williamr@2: #ifndef BOOST_MULTI_INDEX_DETAIL_ITER_ADAPTOR_HPP
williamr@2: #define BOOST_MULTI_INDEX_DETAIL_ITER_ADAPTOR_HPP
williamr@2: 
williamr@2: #if defined(_MSC_VER)&&(_MSC_VER>=1200)
williamr@2: #pragma once
williamr@2: #endif
williamr@2: 
williamr@2: #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
williamr@2: #include <boost/mpl/apply.hpp>
williamr@2: #include <boost/multi_index/detail/prevent_eti.hpp>
williamr@2: #include <boost/operators.hpp>
williamr@2: 
williamr@2: namespace boost{
williamr@2: 
williamr@2: namespace multi_index{
williamr@2: 
williamr@2: namespace detail{
williamr@2: 
williamr@2: /* Poor man's version of boost::iterator_adaptor. Used instead of the
williamr@2:  * original as compile times for the latter are significantly higher.
williamr@2:  * The interface is not replicated exactly, only to the extent necessary
williamr@2:  * for internal consumption.
williamr@2:  */
williamr@2: 
williamr@2: class iter_adaptor_access
williamr@2: {
williamr@2: public:
williamr@2:   template<class Class>
williamr@2:     static typename Class::reference dereference(const Class& x)
williamr@2:   {
williamr@2:     return x.dereference();
williamr@2:   }
williamr@2: 
williamr@2:   template<class Class>
williamr@2:   static bool equal(const Class& x,const Class& y)
williamr@2:   {
williamr@2:     return x.equal(y);
williamr@2:   }
williamr@2: 
williamr@2:   template<class Class>
williamr@2:   static void increment(Class& x)
williamr@2:   {
williamr@2:     x.increment();
williamr@2:   }
williamr@2: 
williamr@2:   template<class Class>
williamr@2:   static void decrement(Class& x)
williamr@2:   {
williamr@2:     x.decrement();
williamr@2:   }
williamr@2: 
williamr@2:   template<class Class>
williamr@2:   static void advance(Class& x,typename Class::difference_type n)
williamr@2:   {
williamr@2:     x.advance(n);
williamr@2:   }
williamr@2: 
williamr@2:   template<class Class>
williamr@2:   static typename Class::difference_type distance_to(
williamr@2:     const Class& x,const Class& y)
williamr@2:   {
williamr@2:     return x.distance_to(y);
williamr@2:   }
williamr@2: };
williamr@2: 
williamr@2: template<typename Category>
williamr@2: struct iter_adaptor_selector;
williamr@2: 
williamr@2: template<class Derived,class Base>
williamr@2: class forward_iter_adaptor_base:
williamr@2:   public forward_iterator_helper<
williamr@2:     Derived,
williamr@2:     typename Base::value_type,
williamr@2:     typename Base::difference_type,
williamr@2:     typename Base::pointer,
williamr@2:     typename Base::reference>
williamr@2: {
williamr@2: public:
williamr@2:   typedef typename Base::reference reference;
williamr@2: 
williamr@2:   reference operator*()const
williamr@2:   {
williamr@2:     return iter_adaptor_access::dereference(final());
williamr@2:   }
williamr@2: 
williamr@2:   friend bool operator==(const Derived& x,const Derived& y)
williamr@2:   {
williamr@2:     return iter_adaptor_access::equal(x,y);
williamr@2:   }
williamr@2: 
williamr@2:   Derived& operator++()
williamr@2:   {
williamr@2:     iter_adaptor_access::increment(final());
williamr@2:     return final();
williamr@2:   }
williamr@2: 
williamr@2: private:
williamr@2:   Derived& final(){return *static_cast<Derived*>(this);}
williamr@2:   const Derived& final()const{return *static_cast<const Derived*>(this);}
williamr@2: };
williamr@2: 
williamr@2: template<>
williamr@2: struct iter_adaptor_selector<std::forward_iterator_tag>
williamr@2: {
williamr@2:   template<class Derived,class Base>
williamr@2:   struct apply
williamr@2:   {
williamr@2:     typedef forward_iter_adaptor_base<Derived,Base> type;
williamr@2:   };
williamr@2: };
williamr@2: 
williamr@2: template<class Derived,class Base>
williamr@2: class bidirectional_iter_adaptor_base:
williamr@2:   public bidirectional_iterator_helper<
williamr@2:     Derived,
williamr@2:     typename Base::value_type,
williamr@2:     typename Base::difference_type,
williamr@2:     typename Base::pointer,
williamr@2:     typename Base::reference>
williamr@2: {
williamr@2: public:
williamr@2:   typedef typename Base::reference reference;
williamr@2: 
williamr@2:   reference operator*()const
williamr@2:   {
williamr@2:     return iter_adaptor_access::dereference(final());
williamr@2:   }
williamr@2: 
williamr@2:   friend bool operator==(const Derived& x,const Derived& y)
williamr@2:   {
williamr@2:     return iter_adaptor_access::equal(x,y);
williamr@2:   }
williamr@2: 
williamr@2:   Derived& operator++()
williamr@2:   {
williamr@2:     iter_adaptor_access::increment(final());
williamr@2:     return final();
williamr@2:   }
williamr@2: 
williamr@2:   Derived& operator--()
williamr@2:   {
williamr@2:     iter_adaptor_access::decrement(final());
williamr@2:     return final();
williamr@2:   }
williamr@2: 
williamr@2: private:
williamr@2:   Derived& final(){return *static_cast<Derived*>(this);}
williamr@2:   const Derived& final()const{return *static_cast<const Derived*>(this);}
williamr@2: };
williamr@2: 
williamr@2: template<>
williamr@2: struct iter_adaptor_selector<std::bidirectional_iterator_tag>
williamr@2: {
williamr@2:   template<class Derived,class Base>
williamr@2:   struct apply
williamr@2:   {
williamr@2:     typedef bidirectional_iter_adaptor_base<Derived,Base> type;
williamr@2:   };
williamr@2: };
williamr@2: 
williamr@2: template<class Derived,class Base>
williamr@2: class random_access_iter_adaptor_base:
williamr@2:   public random_access_iterator_helper<
williamr@2:     Derived,
williamr@2:     typename Base::value_type,
williamr@2:     typename Base::difference_type,
williamr@2:     typename Base::pointer,
williamr@2:     typename Base::reference>
williamr@2: {
williamr@2: public:
williamr@2:   typedef typename Base::reference       reference;
williamr@2:   typedef typename Base::difference_type difference_type;
williamr@2: 
williamr@2:   reference operator*()const
williamr@2:   {
williamr@2:     return iter_adaptor_access::dereference(final());
williamr@2:   }
williamr@2: 
williamr@2:   friend bool operator==(const Derived& x,const Derived& y)
williamr@2:   {
williamr@2:     return iter_adaptor_access::equal(x,y);
williamr@2:   }
williamr@2: 
williamr@2:   friend bool operator<(const Derived& x,const Derived& y)
williamr@2:   {
williamr@2:     return iter_adaptor_access::distance_to(x,y)>0;
williamr@2:   }
williamr@2: 
williamr@2:   Derived& operator++()
williamr@2:   {
williamr@2:     iter_adaptor_access::increment(final());
williamr@2:     return final();
williamr@2:   }
williamr@2: 
williamr@2:   Derived& operator--()
williamr@2:   {
williamr@2:     iter_adaptor_access::decrement(final());
williamr@2:     return final();
williamr@2:   }
williamr@2: 
williamr@2:   Derived& operator+=(difference_type n)
williamr@2:   {
williamr@2:     iter_adaptor_access::advance(final(),n);
williamr@2:     return final();
williamr@2:   }
williamr@2: 
williamr@2:   Derived& operator-=(difference_type n)
williamr@2:   {
williamr@2:     iter_adaptor_access::advance(final(),-n);
williamr@2:     return final();
williamr@2:   }
williamr@2: 
williamr@2:   friend difference_type operator-(const Derived& x,const Derived& y)
williamr@2:   {
williamr@2:     return iter_adaptor_access::distance_to(y,x);
williamr@2:   }
williamr@2: 
williamr@2: private:
williamr@2:   Derived& final(){return *static_cast<Derived*>(this);}
williamr@2:   const Derived& final()const{return *static_cast<const Derived*>(this);}
williamr@2: };
williamr@2: 
williamr@2: template<>
williamr@2: struct iter_adaptor_selector<std::random_access_iterator_tag>
williamr@2: {
williamr@2:   template<class Derived,class Base>
williamr@2:   struct apply
williamr@2:   {
williamr@2:     typedef random_access_iter_adaptor_base<Derived,Base> type;
williamr@2:   };
williamr@2: };
williamr@2: 
williamr@2: template<class Derived,class Base>
williamr@2: struct iter_adaptor_base
williamr@2: {
williamr@2:   typedef iter_adaptor_selector<
williamr@2:     typename Base::iterator_category>        selector;
williamr@2:   typedef typename prevent_eti<
williamr@2:     selector,
williamr@2:     typename mpl::apply2<
williamr@2:       selector,Derived,Base>::type
williamr@2:   >::type                                    type;
williamr@2: };
williamr@2: 
williamr@2: template<class Derived,class Base>
williamr@2: class iter_adaptor:public iter_adaptor_base<Derived,Base>::type
williamr@2: {
williamr@2: protected:
williamr@2:   iter_adaptor(){}
williamr@2:   explicit iter_adaptor(const Base& b_):b(b_){}
williamr@2: 
williamr@2:   const Base& base_reference()const{return b;}
williamr@2:   Base&       base_reference(){return b;}
williamr@2: 
williamr@2: private:
williamr@2:   Base b;
williamr@2: };
williamr@2: 
williamr@2: } /* namespace multi_index::detail */
williamr@2: 
williamr@2: } /* namespace multi_index */
williamr@2: 
williamr@2: } /* namespace boost */
williamr@2: 
williamr@2: #endif