utl/include/utl/concepts/iterators.h
2019-10-13 19:56:47 +03:00

71 lines
2.0 KiB
C++

/*!
* \file /utl/impl/concepts/iterators.h
* \brief utl iterator concept support header
*
* Copyright (C) 2018 Christos Choutouridis
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef __utl_concepts_iterator_h__
#define __utl_concepts_iterator_h__
#include <utl/core/impl.h>
#include <utl/concepts/defines.h>
#include <utl/concepts/stl.h>
/*!
* \ingroup concepts
* \defgroup iterators
*/
//! @{
namespace utl {
#if CXX_CONCEPTS
template <class I>
_utlConcept WeaklyIncrementable =
Semiregular<I> &&
requires(I i) {
{ ++i } -> Same<I>&; // not required to be equality preserving
i++; // not required to be equality preserving
};
#else
namespace detail {
template <typename I> using try_ppI = decltype (++(std::declval<I>()));
template <typename I> using try_Ipp = decltype (std::declval<I>()++);
}
template <class I>
_utlConcept WeaklyIncrementable =
Semiregular<I>
&& Same<_ref_t<I>, meta::detected_t<detail::try_ppI, _ref_t<I>>>
&& meta::is_detected<detail::try_Ipp, _ref_t<I>>::value;
#endif
#if CXX_CONCEPTS
template <class I>
_utlConcept DeviceIterator =
requires(I i) {
{ *i } -> auto&&; // Requires: i is dereferenceable
} &&
WeaklyIncrementable<I>;
#else
#endif
}
//! @}
#endif /* __utl_concepts_iterator_h__ */