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boost/ptr_container/ptr_array.hpp

//
// Boost.Pointer Container
//
//  Copyright Thorsten Ottosen 2003-2005. Use, modification and
//  distribution is 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)
//
// For more information, see http://www.boost.org/libs/ptr_container/
//

#ifndef BOOST_PTR_CONTAINER_PTR_ARRAY_HPP
#define BOOST_PTR_CONTAINER_PTR_ARRAY_HPP

#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif

#include <boost/array.hpp>
#include <boost/static_assert.hpp>
#include <boost/ptr_container/ptr_sequence_adapter.hpp>

namespace boost
{

    namespace ptr_container_detail
    {
        template
        <
            class T,
            size_t N,
            class Allocator = int // dummy
        >
        class ptr_array_impl : public boost::array<T,N>
        {
        public:
            typedef Allocator allocator_type;

            ptr_array_impl( Allocator /*a*/ = Allocator() )
            {
                this->assign( 0 );
            }

            ptr_array_impl( size_t, T*, Allocator /*a*/ = Allocator() )
            {
                this->assign( 0 );
            }
        };
    }

    template
    <
        class T,
        size_t N,
        class CloneAllocator = heap_clone_allocator
    >
    class ptr_array : public
        ptr_sequence_adapter< T,
                              ptr_container_detail::ptr_array_impl<void*,N>,
                              CloneAllocator >
    {
    private:
        typedef ptr_sequence_adapter< T,
                                      ptr_container_detail::ptr_array_impl<void*,N>,
                                      CloneAllocator >
            base_class;

        typedef BOOST_DEDUCED_TYPENAME remove_nullable<T>::type U;

        typedef ptr_array<T,N,CloneAllocator>
                          this_type;

    public:
        typedef std::size_t size_type;
        typedef U*          value_type;
        typedef U*          pointer;
        typedef U&          reference;
        typedef const U&    const_reference;
        typedef BOOST_DEDUCED_TYPENAME base_class::auto_type
                            auto_type;

    public: // constructors
        ptr_array() : base_class()
        { }

        ptr_array( const ptr_array& r )
        {
            size_t i = 0;
            for( ; i != N; ++i )
                this->base()[i] = this->null_policy_allocate_clone( 
                                        static_cast<const T*>( &r[i] ) ); 
        }

        template< class U >
        ptr_array( const ptr_array<U,N>& r )
        {
            size_t i = 0;
            for( ; i != N; ++i )
                this->base()[i] = this->null_policy_allocate_clone( 
                                        static_cast<const T*>( &r[i] ) ); 
        }

        explicit ptr_array( std::auto_ptr<this_type> r )
        : base_class( r ) { }

        ptr_array& operator=( ptr_array r )
        {
            this->swap( r );
            return *this;            
        }

        ptr_array& operator=( std::auto_ptr<this_type> r )
        {
            base_class::operator=(r);
            return *this;
        }

        std::auto_ptr<this_type> release()
        {
            std::auto_ptr<this_type> ptr( new this_type );
            this->swap( *ptr );
            return ptr;
        }

        std::auto_ptr<this_type> clone() const
        {
            std::auto_ptr<this_type> pa( new this_type );
            for( size_t i = 0; i != N; ++i )
            {
                if( ! is_null(i) )
                    pa->replace( i, this->null_policy_allocate_clone( &(*this)[i] ) ); 
            }
            return pa;
        }

    private: // hide some members
        using base_class::insert;
        using base_class::erase;
        using base_class::push_back;
        using base_class::push_front;
        using base_class::pop_front;
        using base_class::pop_back;
        using base_class::transfer;
        using base_class::get_allocator;

    public: // compile-time interface

        template< size_t idx >
        auto_type replace( U* r ) // strong
        {
            BOOST_STATIC_ASSERT( idx < N );

            this->enforce_null_policy( r, "Null pointer in 'ptr_array::replace()'" );

            auto_type res( static_cast<U*>( this->base()[idx] ) ); // nothrow
            this->base()[idx] = r;                                 // nothrow
            return boost::ptr_container::move(res);                // nothrow 
        }

        template< size_t idx, class V >
        auto_type replace( std::auto_ptr<V> r )
        {
            return replace<idx>( r.release() );
        }

        auto_type replace( size_t idx, U* r ) // strong
        {
            this->enforce_null_policy( r, "Null pointer in 'ptr_array::replace()'" );

            auto_type ptr( r );

            BOOST_PTR_CONTAINER_THROW_EXCEPTION( idx >= N, bad_index,
                                                 "'replace()' aout of bounds" );

            auto_type res( static_cast<U*>( this->base()[idx] ) ); // nothrow
            this->base()[idx] = ptr.release();                     // nothrow
            return boost::ptr_container::move(res);                // nothrow 
        }

        template< class V >
        auto_type replace( size_t idx, std::auto_ptr<V> r )
        {
            return replace( idx, r.release() );
        }

        using base_class::at;

        template< size_t idx >
        T& at()
        {
            BOOST_STATIC_ASSERT( idx < N );
            return (*this)[idx];
        }

        template< size_t idx >
        const T& at() const
        {
            BOOST_STATIC_ASSERT( idx < N );
            return (*this)[idx];
        }

        bool is_null( size_t idx ) const
        {
            return base_class::is_null(idx);
        }

        template< size_t idx >
        bool is_null() const
        {
            BOOST_STATIC_ASSERT( idx < N );
            return this->base()[idx] == 0;
        }
    };

    //////////////////////////////////////////////////////////////////////////////
    // clonability

    template< typename T, size_t size, typename CA >
    inline ptr_array<T,size,CA>* new_clone( const ptr_array<T,size,CA>& r )
    {
        return r.clone().release();
    }

    /////////////////////////////////////////////////////////////////////////
    // swap

    template< typename T, size_t size, typename CA >
    inline void swap( ptr_array<T,size,CA>& l, ptr_array<T,size,CA>& r )
    {
        l.swap(r);
    }
}

#endif