dust3d/thirdparty/cgal/CGAL-5.1/include/CGAL/circulator_bases.h

127 lines
4.6 KiB
C++

// Copyright (c) 1997
// Utrecht University (The Netherlands),
// ETH Zurich (Switzerland),
// INRIA Sophia-Antipolis (France),
// Max-Planck-Institute Saarbruecken (Germany),
// and Tel-Aviv University (Israel). All rights reserved.
//
// This file is part of CGAL (www.cgal.org)
//
// $URL: https://github.com/CGAL/cgal/blob/v5.1/Circulator/include/CGAL/circulator_bases.h $
// $Id: circulator_bases.h 0779373 2020-03-26T13:31:46+01:00 Sébastien Loriot
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s) : Lutz Kettner <kettner@inf.ethz.ch>
#ifndef CGAL_CIRCULATOR_BASES_H
#define CGAL_CIRCULATOR_BASES_H 1
#include <cstddef>
#include <iterator>
namespace CGAL {
struct Circulator_tag {}; // any circulator.
struct Iterator_tag {}; // any iterator.
// conversion operators instead of inheritance to avoid ambiguous
// bases. we have to repeat all possible conversion so we don't run
// into a multiple user-defined conversions, problem.
struct Forward_circulator_tag
: public std::forward_iterator_tag
{};
struct Bidirectional_circulator_tag
: public std::bidirectional_iterator_tag
{
operator Forward_circulator_tag() const { return Forward_circulator_tag(); }
};
struct Random_access_circulator_tag
: public std::random_access_iterator_tag
{
operator Bidirectional_circulator_tag() const { return Bidirectional_circulator_tag(); }
operator Forward_circulator_tag() const { return Forward_circulator_tag(); }
};
template <typename Tag, typename T, typename Distance = std::ptrdiff_t,
/* size is so awkwardly placed to faciliate using the
* default arguments from the derived classes */
typename Size = std::size_t, typename Pointer = T*,
typename Reference = T&>
struct Circulator_base {
typedef Tag iterator_category;
typedef T value_type;
typedef Distance difference_type;
typedef Pointer pointer;
typedef Reference reference;
typedef Size size_type;
};
template <class T, class Dist = std::ptrdiff_t, class Size = std::size_t>
struct Forward_circulator_base
: Circulator_base<Forward_circulator_tag, T, Dist, Size> {};
template <class T, class Dist = std::ptrdiff_t, class Size = std::size_t>
struct Bidirectional_circulator_base
: Circulator_base<Bidirectional_circulator_tag, T, Dist, Size> {};
template <class T, class Dist = std::ptrdiff_t, class Size = std::size_t>
struct Random_access_circulator_base
: Circulator_base<Random_access_circulator_tag, T, Dist, Size> {};
// variant base classes
// ---------------------
template <class T, class Dist = std::ptrdiff_t, class Size = std::size_t>
class Forward_circulator_ptrbase // forward circulator.
{
protected:
void* _ptr;
public:
typedef Forward_circulator_tag iterator_category;
typedef T value_type;
typedef Dist difference_type;
typedef Size size_type;
typedef T* pointer;
typedef T& reference;
Forward_circulator_ptrbase() : _ptr(nullptr) {}
Forward_circulator_ptrbase(void* p) : _ptr(p) {}
};
template <class T, class Dist = std::ptrdiff_t, class Size = std::size_t>
class Bidirectional_circulator_ptrbase // bidirectional circulator.
{
protected:
void* _ptr;
public:
typedef Bidirectional_circulator_tag iterator_category;
typedef T value_type;
typedef Dist difference_type;
typedef Size size_type;
typedef T* pointer;
typedef T& reference;
Bidirectional_circulator_ptrbase() : _ptr(nullptr) {}
Bidirectional_circulator_ptrbase(void* p) : _ptr(p) {}
};
template <class T, class Dist = std::ptrdiff_t, class Size = std::size_t>
class Random_access_circulator_ptrbase // random access circulator.
{
protected:
void* _ptr;
public:
typedef Random_access_circulator_tag iterator_category;
typedef T value_type;
typedef Dist difference_type;
typedef Size size_type;
typedef T* pointer;
typedef T& reference;
Random_access_circulator_ptrbase() : _ptr(nullptr) {}
Random_access_circulator_ptrbase(void* p) : _ptr(p) {}
};
} //namespace CGAL
#endif // CGAL_CIRCULATOR_BASES_H //
// EOF //