iterator.hpp

CGAL is a collaborative effort of several sites in Europe and Israel. The goal is to make the most i

//
//  Copyright (c) 2000-2002
//  Joerg Walter, Mathias Koch
//
//  Permission to use, copy, modify, distribute and sell this software
//  and its documentation for any purpose is hereby granted without fee,
//  provided that the above copyright notice appear in all copies and
//  that both that copyright notice and this permission notice appear
//  in supporting documentation.  The authors make no representations
//  about the suitability of this software for any purpose.
//  It is provided "as is" without express or implied warranty.
//
//  The authors gratefully acknowledge the support of
//  GeNeSys mbH & Co. KG in producing this work.
//

#ifndef BOOST_UBLAS_ITERATOR_H
#define BOOST_UBLAS_ITERATOR_H

#include <iterator>

#include <boost/numeric/ublas/exception.hpp>

// Using older GCC the following is missing:
//
// namespace std {
//
//    template <class C, class T, class D = std::ptrdiff_t, class P = T *, class R = T &>
//    struct iterator {
//        typedef C iterator_category;
//        typedef T value_type;
//        typedef D difference_type;
//        typedef P pointer;
//        typedef R reference;
//    };
//
// }
//
// We therefore include the following header
#include <boost/iterator.hpp>
// and use namespace boost instead of std.

namespace boost { namespace numeric { namespace ublas {

  /** \brief Base class of all proxy classes that contain
   *       a (redirectable) reference to an immutable object.
   *
   *       \param C the type of the container referred to
   */
    template<class C>
    class container_const_reference:
        private nonassignable {
    public:
        typedef C container_type;

        BOOST_UBLAS_INLINE
        container_const_reference ():
            c_ (0) {}
        BOOST_UBLAS_INLINE
        container_const_reference (const container_type &c):
            c_ (&c) {}

        BOOST_UBLAS_INLINE
        const container_type &operator () () const {
            return *c_;
        }

        BOOST_UBLAS_INLINE
        container_const_reference &assign (const container_type *c) {
            c_ = c;
            return *this;
        }
        
        // Closure comparison
        BOOST_UBLAS_INLINE
        bool same_closure (const container_const_reference &cr) const {
            return c_ == cr.c_;
        }

    private:
        const container_type *c_;
    };

  /** \brief Base class of all proxy classes that contain
   *         a (redirectable) reference to a mutable object.
   *
   * \param C the type of the container referred to
   */
    template<class C>
    class container_reference:
        private nonassignable {
    public:
        typedef C container_type;

        BOOST_UBLAS_INLINE
        container_reference ():
            c_ (0) {}
        BOOST_UBLAS_INLINE
        container_reference (container_type &c):
            c_ (&c) {}

        BOOST_UBLAS_INLINE
        container_type &operator () () const {
           return *c_;
        }

        BOOST_UBLAS_INLINE
        container_reference &assign (container_type *c) {
            c_ = c;
            return *this;
        }

        // Closure comparison
        BOOST_UBLAS_INLINE
        bool same_closure (const container_reference &cr) const {
            return c_ == cr.c_;
        }

    private:
        container_type *c_;
    };

  /** \brief Base class of all forward iterators.
   * 
   *  \param IC the iterator category
   *  \param I the derived iterator type
   *  \param T the value type
   * 
   * The forward iterator can only proceed in one direction
   * via the post increment operator.
   */
    template<class IC, class I, class T>
    struct forward_iterator_base:
        public boost::iterator<IC, T> {
        typedef I derived_iterator_type;
        typedef T derived_value_type;

        // Arithmetic
        BOOST_UBLAS_INLINE
        derived_iterator_type operator ++ (int) {
            derived_iterator_type &d (*static_cast<const derived_iterator_type *> (this));
            derived_iterator_type tmp (d);
            ++ d;
            return tmp;
        }
#ifndef BOOST_UBLAS_NO_MEMBER_FRIENDS
        BOOST_UBLAS_INLINE
        friend derived_iterator_type operator ++ (derived_iterator_type &d, int) {
            derived_iterator_type tmp (d);
            ++ d;
            return tmp;
        }
#endif

        // Comparison
        BOOST_UBLAS_INLINE
        bool operator != (const derived_iterator_type &it) const {
            const derived_iterator_type *d = static_cast<const derived_iterator_type *> (this);
            return ! (*d == it);
        }
    };

#ifdef BOOST_UBLAS_NO_MEMBER_FRIENDS
    template<class IC, class I, class T>
    BOOST_UBLAS_INLINE
    typename forward_iterator_base<IC, I, T>::derived_iterator_type operator ++ (forward_iterator_base<IC, I, T> &it, int) {
        typedef BOOST_UBLAS_TYPENAME forward_iterator_base<IC, I, T>::derived_iterator_type derived_iterator_type;
        derived_iterator_type &d (static_cast<derived_iterator_type &> (it));
        derived_iterator_type tmp (d);
        ++ d;
        return tmp;
    }
#endif

  /** \brief Base class of all bidirectional iterators.
   *
   * \param IC the iterator category
   * \param I the derived iterator type
   * \param T the value type
   *
   * The bidirectional iterator can proceed in both directions
   * via the post increment and post decrement operator.
   */
    template<class IC, class I, class T>
    struct bidirectional_iterator_base:
        public boost::iterator<IC, T> {
        typedef I derived_iterator_type;
        typedef T derived_value_type;

        // Arithmetic
        BOOST_UBLAS_INLINE
        derived_iterator_type operator ++ (int) {
            derived_iterator_type &d (*static_cast<const derived_iterator_type *> (this));
            derived_iterator_type tmp (d);
            ++ d;
            return tmp;
        }
#ifndef BOOST_UBLAS_NO_MEMBER_FRIENDS
        BOOST_UBLAS_INLINE
        friend derived_iterator_type operator ++ (derived_iterator_type &d, int) {
            derived_iterator_type tmp (d);
            ++ d;
            return tmp;
        }
#endif
        BOOST_UBLAS_INLINE
        derived_iterator_type operator -- (int) {
            derived_iterator_type &d (*static_cast<const derived_iterator_type *> (this));
            derived_iterator_type tmp (d);
            -- d;
            return tmp;
        }
#ifndef BOOST_UBLAS_NO_MEMBER_FRIENDS
        BOOST_UBLAS_INLINE
        friend derived_iterator_type operator -- (derived_iterator_type &d, int) {
            derived_iterator_type tmp (d);
            -- d;
            return tmp;
        }
#endif

        // Comparison
        BOOST_UBLAS_INLINE
        bool operator != (const derived_iterator_type &it) const {
            const derived_iterator_type *d = static_cast<const derived_iterator_type *> (this);
            return ! (*d == it);
        }
    };

#ifdef BOOST_UBLAS_NO_MEMBER_FRIENDS
    template<class IC, class I, class T>
    BOOST_UBLAS_INLINE
    typename bidirectional_iterator_base<IC, I, T>::derived_iterator_type operator ++ (bidirectional_iterator_base<IC, I, T> &it, int) {
        typedef BOOST_UBLAS_TYPENAME bidirectional_iterator_base<IC, I, T>::derived_iterator_type derived_iterator_type;
        derived_iterator_type &d (static_cast<derived_iterator_type &> (it));
        derived_iterator_type tmp (d);
        ++ d;
        return tmp;
    }
    template<class IC, class I, class T>
    BOOST_UBLAS_INLINE
    typename bidirectional_iterator_base<IC, I, T>::derived_iterator_type operator -- (bidirectional_iterator_base<IC, I, T> &it, int) {
        typedef BOOST_UBLAS_TYPENAME bidirectional_iterator_base<IC, I, T>::derived_iterator_type derived_iterator_type;
        derived_iterator_type &d (static_cast<derived_iterator_type &> (it));
        derived_iterator_type tmp (d);
        -- d;
        return tmp;
    }
#endif

  /** \brief Base class of all random access iterators.
   *
   * \param IC the iterator category
   * \param I the derived iterator type
   * \param T the value type
   * \param D the difference type, default: std::ptrdiff_t
   *
   * The random access iterator can proceed in both directions
   * via the post increment/decrement operator or in larger steps
   * via the +, - and +=, -= operators. The random access iterator
   * is LessThan Comparable.
   */
    template<class IC, class I, class T, class D = std::ptrdiff_t>
    // ISSUE the default here seems rather dangerous as it can easlly be (silently) incorrect
    struct random_access_iterator_base:
        public boost::iterator<IC, T> {
        typedef I derived_iterator_type;
        typedef T derived_value_type;
        typedef D derived_difference_type;
#ifdef BOOST_MSVC_STD_ITERATOR
        typedef D difference_type;
#endif

        /*
         *  FIXME Need to explicitly pass derived_refernce_type as otherwise I undefined type or foward declared
        typedef BOOST_UBLAS_TYPENAME derived_iterator_type::reference derived_reference_type;
        // Indexed element
        BOOST_UBLAS_INLINE
        derived_reference_type operator [] (derived_difference_type n) {
            return *(*this + n);
        }
        */

        // Arithmetic
        BOOST_UBLAS_INLINE
        derived_iterator_type operator ++ (int) {
            derived_iterator_type &d (*static_cast<derived_iterator_type *> (this));
            derived_iterator_type tmp (d);
            ++ d;
            return tmp;
        }
#ifndef BOOST_UBLAS_NO_MEMBER_FRIENDS
        BOOST_UBLAS_INLINE
        friend derived_iterator_type operator ++ (derived_iterator_type &d, int) {
            derived_iterator_type tmp (d);
            ++ d;
            return tmp;
        }
#endif
        BOOST_UBLAS_INLINE
        derived_iterator_type operator -- (int) {
            derived_iterator_type &d (*static_cast<derived_iterator_type *> (this));
            derived_iterator_type tmp (d);
            -- d;
            return tmp;
        }
#ifndef BOOST_UBLAS_NO_MEMBER_FRIENDS
        BOOST_UBLAS_INLINE
        friend derived_iterator_type operator -- (derived_iterator_type &d, int) {
            derived_iterator_type tmp (d);
            -- d;
            return tmp;
        }
#endif
        BOOST_UBLAS_INLINE
        derived_iterator_type operator + (derived_difference_type n) const {
            derived_iterator_type tmp (*static_cast<const derived_iterator_type *> (this));
            return tmp += n;
        }
#ifndef BOOST_UBLAS_NO_MEMBER_FRIENDS
        BOOST_UBLAS_INLINE
        friend derived_iterator_type operator + (const derived_iterator_type &d, derived_difference_type n) {
            derived_iterator_type tmp (d);
            return tmp += n;
        }
        BOOST_UBLAS_INLINE
        friend derived_iterator_type operator + (derived_difference_type n, const derived_iterator_type &d) {
            derived_iterator_type tmp (d);
            return tmp += n;
        }
#endif
        BOOST_UBLAS_INLINE
        derived_iterator_type operator - (derived_difference_type n) const {
            derived_iterator_type tmp (*static_cast<const derived_iterator_type *> (this));
            return tmp -= n;
        }
#ifndef BOOST_UBLAS_NO_MEMBER_FRIENDS
        BOOST_UBLAS_INLINE
        friend derived_iterator_type operator - (const derived_iterator_type &d, derived_difference_type n) {
            derived_iterator_type tmp (d);
            return tmp -= n;
        }
#endif

        // Comparison
        BOOST_UBLAS_INLINE
        bool operator != (const derived_iterator_type &it) const {
            const derived_iterator_type *d = static_cast<const derived_iterator_type *> (this);
            return ! (*d == it);
        }
        BOOST_UBLAS_INLINE
        bool operator <= (const derived_iterator_type &it) const {
            const derived_iterator_type *d = static_cast<const derived_iterator_type *> (this);
            return ! (it < *d);
        }
        BOOST_UBLAS_INLINE
        bool operator >= (const derived_iterator_type &it) const {
            const derived_iterator_type *d = static_cast<const derived_iterator_type *> (this);
            return ! (*d < it);
        }
        BOOST_UBLAS_INLINE
        bool operator > (const derived_iterator_type &it) const {
            const derived_iterator_type *d = static_cast<const derived_iterator_type *> (this);
            return it < *d;
        }
    };

#ifdef BOOST_UBLAS_NO_MEMBER_FRIENDS
    template<class IC, class I, class T>