williamr@4: // Copyright 2002 The Trustees of Indiana University.
williamr@4: 
williamr@4: // Use, modification and distribution is subject to the Boost Software 
williamr@4: // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
williamr@4: // http://www.boost.org/LICENSE_1_0.txt)
williamr@4: 
williamr@4: //  Boost.MultiArray Library
williamr@4: //  Authors: Ronald Garcia
williamr@4: //           Jeremy Siek
williamr@4: //           Andrew Lumsdaine
williamr@4: //  See http://www.boost.org/libs/multi_array for documentation.
williamr@4: 
williamr@4: #ifndef ITERATOR_RG071801_HPP
williamr@4: #define ITERATOR_RG071801_HPP
williamr@4: 
williamr@4: //
williamr@4: // iterator.hpp - implementation of iterators for the
williamr@4: // multi-dimensional array class
williamr@4: //
williamr@4: 
williamr@4: #include "boost/multi_array/base.hpp"
williamr@4: #include "boost/iterator/iterator_facade.hpp"
williamr@4: #include "boost/mpl/aux_/msvc_eti_base.hpp"
williamr@4: #include <algorithm>
williamr@4: #include <cstddef>
williamr@4: #include <iterator>
williamr@4: 
williamr@4: namespace boost {
williamr@4: namespace detail {
williamr@4: namespace multi_array {
williamr@4: 
williamr@4: /////////////////////////////////////////////////////////////////////////
williamr@4: // iterator components
williamr@4: /////////////////////////////////////////////////////////////////////////
williamr@4: 
williamr@4: template <class T>
williamr@4: struct operator_arrow_proxy
williamr@4: {
williamr@4:   operator_arrow_proxy(T const& px) : value_(px) {}
williamr@4:   T* operator->() const { return &value_; }
williamr@4:   // This function is needed for MWCW and BCC, which won't call operator->
williamr@4:   // again automatically per 13.3.1.2 para 8
williamr@4:   operator T*() const { return &value_; }
williamr@4:   mutable T value_;
williamr@4: };
williamr@4: 
williamr@4: template <typename T, typename TPtr, typename NumDims, typename Reference>
williamr@4: class array_iterator;
williamr@4: 
williamr@4: template <typename T, typename TPtr, typename NumDims, typename Reference>
williamr@4: class array_iterator
williamr@4:   : public
williamr@4:     iterator_facade<
williamr@4:         array_iterator<T,TPtr,NumDims,Reference>
williamr@4:       , typename associated_types<T,NumDims>::value_type
williamr@4:       , boost::random_access_traversal_tag
williamr@4:       , Reference
williamr@4:     >
williamr@4:     , private
williamr@4: #if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
williamr@4:       mpl::aux::msvc_eti_base<typename 
williamr@4: #endif 
williamr@4:           value_accessor_generator<T,NumDims>::type
williamr@4: #if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
williamr@4:       >::type
williamr@4: #endif 
williamr@4: {
williamr@4:   friend class iterator_core_access;
williamr@4:   typedef detail::multi_array::associated_types<T,NumDims> access_t;
williamr@4: 
williamr@4:   typedef iterator_facade<
williamr@4:         array_iterator<T,TPtr,NumDims,Reference>
williamr@4:       , typename detail::multi_array::associated_types<T,NumDims>::value_type
williamr@4:       , boost::random_access_traversal_tag
williamr@4:       , Reference
williamr@4:     > facade_type;
williamr@4: 
williamr@4:   typedef typename access_t::index index;
williamr@4:   typedef typename access_t::size_type size_type;
williamr@4: 
williamr@4: #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
williamr@4:   template <typename, typename, typename, typename>
williamr@4:     friend class array_iterator;
williamr@4: #else
williamr@4:  public:
williamr@4: #endif 
williamr@4: 
williamr@4:   index idx_;
williamr@4:   TPtr base_;
williamr@4:   const size_type* extents_;
williamr@4:   const index* strides_;
williamr@4:   const index* index_base_;
williamr@4:  
williamr@4: public:
williamr@4:   // Typedefs to circumvent ambiguities between parent classes
williamr@4:   typedef typename facade_type::reference reference;
williamr@4:   typedef typename facade_type::value_type value_type;
williamr@4:   typedef typename facade_type::difference_type difference_type;
williamr@4: 
williamr@4:   array_iterator() {}
williamr@4: 
williamr@4:   array_iterator(index idx, TPtr base, const size_type* extents,
williamr@4:                 const index* strides,
williamr@4:                 const index* index_base) :
williamr@4:     idx_(idx), base_(base), extents_(extents),
williamr@4:     strides_(strides), index_base_(index_base) { }
williamr@4: 
williamr@4:   template <typename OPtr, typename ORef>
williamr@4:   array_iterator(
williamr@4:       const array_iterator<T,OPtr,NumDims,ORef>& rhs
williamr@4:     , typename boost::enable_if_convertible<OPtr,TPtr>::type* = 0
williamr@4:   )
williamr@4:     : idx_(rhs.idx_), base_(rhs.base_), extents_(rhs.extents_),
williamr@4:     strides_(rhs.strides_), index_base_(rhs.index_base_) { }
williamr@4: 
williamr@4: 
williamr@4:   // RG - we make our own operator->
williamr@4:   operator_arrow_proxy<reference>
williamr@4:   operator->() const
williamr@4:   {
williamr@4:     return operator_arrow_proxy<reference>(this->dereference());
williamr@4:   }
williamr@4:   
williamr@4: 
williamr@4:   reference dereference() const
williamr@4:   {
williamr@4:     typedef typename value_accessor_generator<T,NumDims>::type accessor;
williamr@4:     return accessor::access(boost::type<reference>(),
williamr@4:                             idx_,
williamr@4:                             base_,
williamr@4:                             extents_,
williamr@4:                             strides_,
williamr@4:                             index_base_);
williamr@4:   }
williamr@4:   
williamr@4:   void increment() { ++idx_; }
williamr@4:   void decrement() { --idx_; }
williamr@4: 
williamr@4:   template <class IteratorAdaptor>
williamr@4:   bool equal(IteratorAdaptor& rhs) const {
williamr@4:     const std::size_t N = NumDims::value;
williamr@4:     return (idx_ == rhs.idx_) &&
williamr@4:       (base_ == rhs.base_) &&
williamr@4:       ( (extents_ == rhs.extents_) ||
williamr@4:         std::equal(extents_,extents_+N,rhs.extents_) ) &&
williamr@4:       ( (strides_ == rhs.strides_) ||
williamr@4:         std::equal(strides_,strides_+N,rhs.strides_) ) &&
williamr@4:       ( (index_base_ == rhs.index_base_) ||
williamr@4:         std::equal(index_base_,index_base_+N,rhs.index_base_) );
williamr@4:   }
williamr@4: 
williamr@4:   template <class DifferenceType>
williamr@4:   void advance(DifferenceType n) {
williamr@4:     idx_ += n;
williamr@4:   }
williamr@4: 
williamr@4:   template <class IteratorAdaptor>
williamr@4:   typename facade_type::difference_type
williamr@4:   distance_to(IteratorAdaptor& rhs) const {
williamr@4:     return rhs.idx_ - idx_;
williamr@4:   }
williamr@4: 
williamr@4: 
williamr@4: };
williamr@4: 
williamr@4: } // namespace multi_array
williamr@4: } // namespace detail
williamr@4: } // namespace boost
williamr@4: 
williamr@4: #endif // ITERATOR_RG071801_HPP