Sprout/sprout/algorithm/find.hpp
2012-12-11 12:59:36 +09:00

71 lines
2.3 KiB
C++

#ifndef SPROUT_ALGORITHM_FIND_HPP
#define SPROUT_ALGORITHM_FIND_HPP
#include <iterator>
#include <sprout/config.hpp>
#include <sprout/iterator/operation.hpp>
#include HDR_ITERATOR_SSCRISK_CEL_OR_SPROUT
namespace sprout {
namespace detail {
template<typename RandomAccessIterator, typename T>
inline SPROUT_CONSTEXPR RandomAccessIterator
find_impl_ra(
RandomAccessIterator first, RandomAccessIterator last, T const& value,
typename std::iterator_traits<RandomAccessIterator>::difference_type pivot, RandomAccessIterator found
)
{
return found != first ? found
: pivot == 0 ? (*first == value ? first : last)
: sprout::detail::find_impl_ra(
sprout::next(first, pivot), last, value,
(NS_SSCRISK_CEL_OR_SPROUT::distance(first, last) - pivot) / 2,
sprout::detail::find_impl_ra(
first, sprout::next(first, pivot), value,
pivot / 2,
first
)
)
;
}
template<typename RandomAccessIterator, typename T>
inline SPROUT_CONSTEXPR RandomAccessIterator
find(
RandomAccessIterator first, RandomAccessIterator last, T const& value,
std::random_access_iterator_tag*
)
{
return first == last ? last
: sprout::detail::find_impl_ra(first, last, value, NS_SSCRISK_CEL_OR_SPROUT::distance(first, last) / 2, first)
;
}
// Copyright (C) 2011 RiSK (sscrisk)
template<typename InputIterator, typename T>
inline SPROUT_CONSTEXPR InputIterator
find_impl(InputIterator first, InputIterator last, T const& value) {
return first == last || *first == value ? first
: sprout::detail::find_impl(sprout::next(first), last, value)
;
}
template<typename InputIterator, typename T>
inline SPROUT_CONSTEXPR InputIterator
find(
InputIterator first, InputIterator last, T const& value,
void*
)
{
return sprout::detail::find_impl(first, last, value);
}
} //namespace detail
// 25.2.5 Find
template<typename InputIterator, typename T>
inline SPROUT_CONSTEXPR InputIterator
find(InputIterator first, InputIterator last, T const& value) {
typedef typename std::iterator_traits<InputIterator>::iterator_category* category;
return sprout::detail::find(first, last, value, category());
}
} // namespace sprout
#endif // #ifndef SPROUT_ALGORITHM_FIND_HPP