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// Copyright (c) 2014 GeometryFactory (France). All rights reserved.
//
// This file is part of CGAL (www.cgal.org)
//
// $URL: https://github.com/CGAL/cgal/blob/v6.1/STL_Extension/include/CGAL/Iterator_range.h $
// $Id: include/CGAL/Iterator_range.h b26b07a1242 $
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s) : Andreas Fabri
#ifndef CGAL_ITERATOR_RANGE_H
#define CGAL_ITERATOR_RANGE_H
#include <CGAL/tuple.h>
#include <utility>
#include <boost/foreach.hpp>
namespace CGAL {
/*!
\ingroup PkgSTLExtensionRef
`CGAL::Iterator_range` encapsulates two iterators so they fulfill the `ForwardRange` concept.
The class is essentially a clone of <A
href="https://www.boost.org/doc/libs/1_55_0/libs/range/doc/html/range/reference/utilities/iterator_range.html">`boost::iterator_range`</A>,
and it additionally is derived from `std::pair`, so that one can apply `boost::tie`.
*/
template <typename I>
class Iterator_range : public std::pair<I, I>
{
typedef std::pair<I, I> Base;
public:
typedef I iterator;
typedef I const_iterator;
Iterator_range() = default;
Iterator_range(I b, I e)
: Base(b, e) {}
Iterator_range(const std::pair<I, I>& ip)
: Base(ip) {}
I begin() const { return this->first; }
I end() const { return this->second; }
/// returns `std::distance(begin(), end())`
std::size_t size() const { return static_cast<std::size_t>(std::distance(begin(), end())); }
/// returns `std::distance(begin(), end())==0`
bool empty() const { return begin() == end(); }
operator std::tuple<I&, I&>()
{
return std::tuple<I&, I&>{this->first, this->second};
}
operator std::tuple<const I&, const I&>() const
{
return std::tuple<const I&, const I&>{this->first, this->second};
}
template <template<class...> class Container>
auto to() const
{
using V = std::remove_cv_t<std::remove_reference_t<decltype(*begin())>>;
return Container<V>(begin(), end());
}
};
template <typename T>
Iterator_range<T>
make_range(const T& b, const T&e)
{
return Iterator_range<T>(b,e);
}
template <typename T>
Iterator_range<T>
make_range(const std::pair<T,T>& p)
{
return Iterator_range<T>(p.first,p.second);
}
} // namespace CGAL
namespace boost::foreach {
template<typename T>
struct is_lightweight_proxy<CGAL::Iterator_range<T>> : boost::mpl::true_ {};
}
#if CGAL_CXX20 && __cpp_lib_ranges >= 201911L
# include <ranges>
template<typename I>
inline constexpr bool std::ranges::enable_borrowed_range<CGAL::Iterator_range<I>> = true;
#endif // C++20
#endif // CGAL_ITERATOR_RANGE_H
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