Sprout/sprout/iterator/joint_iterator.hpp
2013-01-03 17:01:50 +09:00

335 lines
11 KiB
C++

#ifndef SPROUT_ITERATOR_JOINT_ITERATOR_HPP
#define SPROUT_ITERATOR_JOINT_ITERATOR_HPP
#include <iterator>
#include <utility>
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/iterator/next.hpp>
#include <sprout/iterator/prev.hpp>
#include <sprout/iterator/distance.hpp>
#include <sprout/iterator/type_traits/common.hpp>
#include <sprout/utility/swap.hpp>
#include <sprout/utility/limited.hpp>
#include <sprout/type_traits/arithmetic_promote.hpp>
#include <sprout/iterator/operation.hpp>
namespace sprout {
//
// joint_iterator
//
template<typename LIterator, typename RIterator>
class joint_iterator
: public std::iterator<
typename sprout::common_iterator_category<LIterator, RIterator>::type,
typename sprout::common_iterator_value_type<LIterator, RIterator>::type,
typename sprout::common_iterator_difference_type<LIterator, RIterator>::type,
typename sprout::common_iterator_pointer<LIterator, RIterator>::type,
typename sprout::common_iterator_reference<LIterator, RIterator>::type
>
{
public:
typedef LIterator iterator_type;
typedef RIterator iterator2_type;
typedef typename sprout::common_iterator_category<LIterator, RIterator>::type iterator_category;
typedef typename sprout::common_iterator_value_type<LIterator, RIterator>::type value_type;
typedef typename sprout::common_iterator_difference_type<LIterator, RIterator>::type difference_type;
typedef typename sprout::common_iterator_pointer<LIterator, RIterator>::type pointer;
typedef typename sprout::common_iterator_reference<LIterator, RIterator>::type reference;
protected:
iterator_type current1;
iterator_type last1;
iterator2_type first2;
iterator2_type current2;
private:
SPROUT_CONSTEXPR joint_iterator advance_impl_posite(difference_type n, difference_type d) const {
return n > d ? joint_iterator(last1, last1, first2, sprout::next(current2, n - d))
: joint_iterator(sprout::next(current1, n), last1, first2, current2)
;
}
SPROUT_CONSTEXPR joint_iterator advance_impl_negate(difference_type n, difference_type d) const {
return !(n > d) ? joint_iterator(sprout::next(current1, n - d), last1, first2, first2)
: joint_iterator(current1, last1, first2, sprout::next(current2, n))
;
}
SPROUT_CONSTEXPR joint_iterator advance_impl(difference_type n) const {
return n >= 0
? is_in_left()
? advance_impl_posite(n, sprout::distance(current1, last1))
: joint_iterator(current1, last1, first2, sprout::next(current2, n))
: first2 == current2
? joint_iterator(sprout::next(current1, n), last1, first2, current2)
: advance_impl_negate(n, -sprout::distance(first2, current2))
;
}
public:
joint_iterator() = default;
joint_iterator(joint_iterator const&) = default;
SPROUT_CONSTEXPR joint_iterator(iterator_type it1, iterator_type last1, iterator2_type first2, iterator2_type it2)
: current1(it1)
, last1(last1)
, first2(first2)
, current2(it2)
{}
template<typename U, typename V>
SPROUT_CONSTEXPR joint_iterator(joint_iterator<U, V> const& it)
: current1(it.base())
, last1(it.left_end())
, first2(it.right_begin())
, current2(it.base2())
{}
template<typename U, typename V>
joint_iterator& operator=(joint_iterator<U, V> const& it) {
joint_iterator temp(it);
temp.swap(*this);
return *this;
}
SPROUT_CONSTEXPR iterator_type base() const {
return current1;
}
SPROUT_CONSTEXPR iterator_type left_end() const {
return last1;
}
SPROUT_CONSTEXPR iterator2_type right_begin() const {
return first2;
}
SPROUT_CONSTEXPR iterator2_type base2() const {
return current2;
}
SPROUT_CONSTEXPR bool is_in_left() const {
return current1 != last1;
}
SPROUT_CONSTEXPR reference operator*() const {
return is_in_left() ? *current1 : *current2;
}
SPROUT_CONSTEXPR pointer operator->() const {
return &*(*this);
}
joint_iterator& operator++() {
if (is_in_left()) {
++current1;
} else {
++current2;
}
return *this;
}
joint_iterator operator++(int) {
joint_iterator result(*this);
if (is_in_left()) {
++current1;
} else {
++current2;
}
return result;
}
joint_iterator& operator--() {
if (first2 == current2) {
--current1;
} else {
--current2;
}
return *this;
}
joint_iterator operator--(int) {
joint_iterator temp(*this);
if (first2 == current2) {
--current1;
} else {
--current2;
}
return temp;
}
SPROUT_CONSTEXPR joint_iterator operator+(difference_type n) const {
return advance_impl(n);
}
SPROUT_CONSTEXPR joint_iterator operator-(difference_type n) const {
return advance_impl(-n);
}
joint_iterator& operator+=(difference_type n) {
joint_iterator temp(*this + n);
temp.swap(*this);
return *this;
}
joint_iterator& operator-=(difference_type n) {
joint_iterator temp(*this - n);
temp.swap(*this);
return *this;
}
SPROUT_CONSTEXPR reference operator[](difference_type n) const {
return *(*this + n);
}
SPROUT_CONSTEXPR joint_iterator next() const {
return is_in_left() ? joint_iterator(sprout::next(current1), last1, first2, current2)
: joint_iterator(current1, last1, first2, sprout::next(current2))
;
}
SPROUT_CONSTEXPR joint_iterator prev() const {
return first2 == current2 ? joint_iterator(sprout::prev(current1), last1, first2, current2)
: joint_iterator(current1, last1, first2, sprout::prev(current2))
;
}
void swap(joint_iterator& other)
SPROUT_NOEXCEPT_EXPR(
SPROUT_NOEXCEPT_EXPR(sprout::swap(current1, other.current1))
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(last1, other.last1))
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(first2, other.first2))
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(current2, other.current2))
)
{
sprout::swap(current1, other.current1);
sprout::swap(last1, other.last1);
sprout::swap(first2, other.first2);
sprout::swap(current2, other.current2);
}
};
template<
typename LIterator1, typename RIterator1,
typename LIterator2, typename RIterator2
>
inline SPROUT_CONSTEXPR bool operator==(
sprout::joint_iterator<LIterator1, RIterator1> const& lhs,
sprout::joint_iterator<LIterator2, RIterator2> const& rhs
)
{
return lhs.base() == rhs.base() && lhs.base2() == rhs.base2();
}
template<
typename LIterator1, typename RIterator1,
typename LIterator2, typename RIterator2
>
inline SPROUT_CONSTEXPR bool operator!=(
sprout::joint_iterator<LIterator1, RIterator1> const& lhs,
sprout::joint_iterator<LIterator2, RIterator2> const& rhs
)
{
return !(lhs == rhs);
}
template<
typename LIterator1, typename RIterator1,
typename LIterator2, typename RIterator2
>
inline SPROUT_CONSTEXPR bool operator<(
sprout::joint_iterator<LIterator1, RIterator1> const& lhs,
sprout::joint_iterator<LIterator2, RIterator2> const& rhs
)
{
return lhs.is_in_left() && rhs.is_in_left() ? lhs.base() < rhs.base()
: !lhs.is_in_left() && !rhs.is_in_left() ? lhs.base2() < rhs.base2()
: lhs.is_in_left()
;
}
template<
typename LIterator1, typename RIterator1,
typename LIterator2, typename RIterator2
>
inline SPROUT_CONSTEXPR bool operator>(
sprout::joint_iterator<LIterator1, RIterator1> const& lhs,
sprout::joint_iterator<LIterator2, RIterator2> const& rhs
)
{
return rhs < lhs;
}
template<
typename LIterator1, typename RIterator1,
typename LIterator2, typename RIterator2
>
inline SPROUT_CONSTEXPR bool operator<=(
sprout::joint_iterator<LIterator1, RIterator1> const& lhs,
sprout::joint_iterator<LIterator2, RIterator2> const& rhs
)
{
return !(rhs < lhs);
}
template<
typename LIterator1, typename RIterator1,
typename LIterator2, typename RIterator2
>
inline SPROUT_CONSTEXPR bool operator>=(
sprout::joint_iterator<LIterator1, RIterator1> const& lhs,
sprout::joint_iterator<LIterator2, RIterator2> const& rhs
)
{
return !(lhs < rhs);
}
template<
typename LIterator1, typename RIterator1,
typename LIterator2, typename RIterator2
>
inline SPROUT_CONSTEXPR typename sprout::arithmetic_promote<
typename sprout::joint_iterator<LIterator1, RIterator1>::difference_type,
typename sprout::joint_iterator<LIterator2, RIterator2>::difference_type
>::type
operator-(
sprout::joint_iterator<LIterator1, RIterator1> const& lhs,
sprout::joint_iterator<LIterator2, RIterator2> const& rhs
)
{
return lhs.is_in_left() && rhs.is_in_left() ? rhs.base() - lhs.base()
: !lhs.is_in_left() && !rhs.is_in_left() ? rhs.base2() - lhs.base2()
: lhs.is_in_left() ? sprout::limited::plus(lhs.left_end() - lhs.base(), rhs.base2() - rhs.right_begin())
: sprout::limited::plus(lhs.base2() - lhs.right_begin(), rhs.left_end() - rhs.base())
;
}
template<typename LIterator, typename RIterator>
inline SPROUT_CONSTEXPR sprout::joint_iterator<LIterator, RIterator> operator+(
typename sprout::joint_iterator<LIterator, RIterator>::difference_type n,
sprout::joint_iterator<LIterator, RIterator> const& it
)
{
return it + n;
}
//
// make_joint_iterator
//
template<typename LIterator, typename RIterator>
inline SPROUT_CONSTEXPR sprout::joint_iterator<LIterator, RIterator>
make_joint_iterator(LIterator it1, LIterator last1, RIterator first2, RIterator it2) {
return sprout::joint_iterator<LIterator, RIterator>(it1, last1, first2, it2);
}
template<typename LIterator, typename RIterator>
inline SPROUT_CONSTEXPR sprout::joint_iterator<LIterator, RIterator>
make_joint_iterator(LIterator it1, LIterator last1, RIterator first2) {
return sprout::joint_iterator<LIterator, RIterator>(it1, last1, first2, first2);
}
template<typename LIterator, typename RIterator>
inline SPROUT_CONSTEXPR sprout::joint_iterator<LIterator, RIterator>
make_joint_iterator(LIterator last1, RIterator first2, RIterator it2) {
return sprout::joint_iterator<LIterator, RIterator>(last1, last1, first2, it2);
}
//
// swap
//
template<typename LIterator, typename RIterator>
inline void
swap(
sprout::joint_iterator<LIterator, RIterator>& lhs,
sprout::joint_iterator<LIterator, RIterator>& rhs
)
SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(lhs.swap(rhs)))
{
lhs.swap(rhs);
}
//
// iterator_next
//
template<typename LIterator, typename RIterator>
inline SPROUT_CONSTEXPR sprout::joint_iterator<LIterator, RIterator>
iterator_next(sprout::joint_iterator<LIterator, RIterator> const& it) {
return it.next();
}
//
// iterator_prev
//
template<typename LIterator, typename RIterator>
inline SPROUT_CONSTEXPR sprout::joint_iterator<LIterator, RIterator>
iterator_prev(sprout::joint_iterator<LIterator, RIterator> const& it) {
return it.prev();
}
} // namespace sprout
#endif // #ifndef SPROUT_ITERATOR_JOINT_ITERATOR_HPP