ahIterator.H

Go to the documentation of this file.

 
/*
                          Aleph_w
 
  Data structures & Algorithms
  version 2.0.0b
  https://github.com/lrleon/Aleph-w
 
  This file is part of Aleph-w library
 
  Copyright (c) 2002-2026 Leandro Rabindranath Leon
 
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
 
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
 
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/
 
 
# ifndef AHITERATOR_H
# define AHITERATOR_H
 
# include <type_traits>
 
namespace Aleph
{
 
  template <class Itor>
  struct iterator_traits
  {
    typedef typename Itor::value_type value_type;         
    typedef typename Itor::difference_type difference_type; 
    typedef typename Itor::pointer pointer;               
    typedef typename Itor::reference reference;           
  };
 
# define STL_ITOR_SPEC(It_Name)           \
  public:               \
                  \
  using T = typename Set_Type::Item_Type;       \
  using Itor = typename Set_Type::Iterator;       \
                  \
  using Itor::Itor;             \
                  \
  Itor operator ++ ()             \
  {                 \
    this->next();             \
    return *this;             \
  }                 \
                  \
  Itor operator ++ (int)            \
  {                 \
    Itor ret_val = *this;           \
    this->next();             \
    return ret_val;             \
  }                 \
                  \
  bool operator == (const Itor & it) const noexcept     \
  {                 \
    if (this->has_curr() and it.has_curr())       \
      return this->get_pos() == it.get_pos();       \
                  \
    if (not this->has_curr() and not it.has_curr())     \
      return true;              \
                  \
    return false;             \
  }                 \
                  \
  bool operator != (const Itor & it) const noexcept     \
  {                 \
    return not (*this == it);           \
  }
 
 
  template <class Set_Type>
  struct __iterator : public Set_Type::Iterator
  {
    STL_ITOR_SPEC(__iterator);
 
    // Note: operator* must be const to satisfy std::indirectly_readable concept
    // (required by std::ranges::input_iterator). The constness of the iterator
    // does not affect the constness of the pointed-to value.
    T &operator *() const { return const_cast<T &>(this->get_curr()); }
 
    T * operator ->() const
    {
      return &const_cast<T &>(this->get_curr());
    }
 
    static __iterator begin(const Set_Type & s) noexcept
    {
      return __iterator(s);
    }
 
    static __iterator end(const Set_Type & s) noexcept
    {
      __iterator it(s);
      it.Itor::end();
      return it;
    }
  };
 
  template <class Set_Type>
  struct __const_iterator : public Set_Type::Iterator
  {
    STL_ITOR_SPEC(__const_iterator);
 
    const T &operator *() const noexcept { return this->get_curr(); }
 
    T const * operator ->() const noexcept
    {
      return const_cast<T *>(&this->get_curr());
    }
 
    static __const_iterator cbegin(const Set_Type & s) noexcept
    {
      return __const_iterator(s);
    }
 
    static __const_iterator cend(const Set_Type & s) noexcept
    {
      __const_iterator it(s);
      it.Itor::end();
      return it;
    }
  };
 
 
# define STL_ALEPH_ITERATOR(Set_Name)         \
  using iterator = __iterator<Set_Name>;        \
                  \
  using const_iterator = __const_iterator<Set_Name>;      \
                  \
  iterator begin() noexcept { return iterator::begin(*this); }    \
                  \
  iterator end() noexcept { return iterator::end(*this); }    \
                  \
  const_iterator begin() const noexcept         \
  {                 \
    return const_iterator::cbegin(*this);       \
  }                 \
                  \
  const_iterator end() const noexcept         \
  {                 \
    return const_iterator::cend(*this);         \
  }                 \
                    \
  const_iterator cbegin() const noexcept        \
  {                 \
    return const_iterator::cbegin(*this);       \
  }                 \
                  \
  const_iterator cend() const noexcept          \
  {                 \
    return const_iterator::cend(*this);         \
  }                 \
                  \
  const_iterator cbegin() noexcept          \
  {                 \
    return const_iterator::cbegin(*this);       \
  }                 \
                    \
  const_iterator cend() noexcept          \
  {                 \
    return const_iterator::cend(*this);         \
  }                 \
                  \
  friend const_iterator cbegin(const Set_Name & s) noexcept   \
  { return s.begin(); }             \
                  \
  friend const_iterator cend(const Set_Name & s) noexcept   \
  { return s.end(); }             \
                    \
  friend const_iterator begin(const Set_Name & s) noexcept    \
  { return s.begin(); }             \
                  \
  friend const_iterator end(const Set_Name & s) noexcept    \
  { return s.end(); }             \
                  \
  friend iterator begin(Set_Name & s) noexcept { return s.begin(); }  \
                  \
  friend iterator end(Set_Name & s) noexcept { return s.end(); }
 
# ifdef nada
  inline template <class Itor>
  typename iterator_traits<Itor>::difference_type distance(Itor it1, Itor it2)
  {
    typename iterator_traits<Itor>::difference_type d = 0;
 
    while (it1 not_eq it2)
      {
        d++;
        it1++;
      }
 
    return d;
  }
 
# endif
}; // end namespace Aleph
 
# endif // AHITERATOR_H