mirror of
https://github.com/bolero-MURAKAMI/Sprout.git
synced 2024-11-25 00:43:44 +00:00
250 lines
8.2 KiB
C++
250 lines
8.2 KiB
C++
/*=============================================================================
|
|
Copyright (c) 2011-2017 Bolero MURAKAMI
|
|
https://github.com/bolero-MURAKAMI/Sprout
|
|
|
|
Distributed under the Boost Software License, Version 1.0. (See accompanying
|
|
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|
=============================================================================*/
|
|
#ifndef SPROUT_ITERATOR_MERGE_ITERATOR_HPP
|
|
#define SPROUT_ITERATOR_MERGE_ITERATOR_HPP
|
|
|
|
#include <iterator>
|
|
#include <utility>
|
|
#include <type_traits>
|
|
#include <sprout/config.hpp>
|
|
#include <sprout/iterator/iterator.hpp>
|
|
#include <sprout/iterator/next.hpp>
|
|
#include <sprout/iterator/type_traits/common.hpp>
|
|
#include <sprout/functional/less.hpp>
|
|
#include <sprout/utility/swap.hpp>
|
|
|
|
namespace sprout {
|
|
//
|
|
// merge_iterator
|
|
//
|
|
template<
|
|
typename LIterator, typename RIterator,
|
|
typename Compare = sprout::less<>
|
|
>
|
|
class merge_iterator
|
|
: public sprout::iterator<
|
|
typename sprout::min_iterator_category<
|
|
typename sprout::common_iterator_category<LIterator, RIterator>::type,
|
|
std::forward_iterator_tag
|
|
>::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 Compare compare_type;
|
|
typedef typename sprout::min_iterator_category<
|
|
typename sprout::common_iterator_category<LIterator, RIterator>::type,
|
|
std::forward_iterator_tag
|
|
>::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;
|
|
private:
|
|
static SPROUT_CONSTEXPR bool check_in_left(
|
|
iterator_type it1, iterator_type las1,
|
|
iterator2_type it2, iterator2_type las2,
|
|
Compare comp
|
|
)
|
|
{
|
|
return it1 != las1 ? (it2 != las2 ? !comp(*it2, *it1) : true)
|
|
: !(it2 != las2)
|
|
;
|
|
}
|
|
protected:
|
|
iterator_type current1;
|
|
iterator_type las1;
|
|
iterator2_type current2;
|
|
iterator2_type las2;
|
|
Compare comp;
|
|
bool in_left;
|
|
public:
|
|
SPROUT_CONSTEXPR merge_iterator()
|
|
: current1(), las1(), current2(), las2(), comp(), in_left(true)
|
|
{}
|
|
merge_iterator(merge_iterator const&) = default;
|
|
SPROUT_CONSTEXPR merge_iterator(
|
|
iterator_type it1, iterator_type las1,
|
|
iterator2_type it2, iterator2_type las2,
|
|
Compare comp = Compare()
|
|
)
|
|
: current1(it1), las1(las1)
|
|
, current2(it2), las2(las2)
|
|
, comp(comp)
|
|
, in_left(check_in_left(it1, las1, it2, las2, comp))
|
|
{}
|
|
template<typename U, typename V, typename W>
|
|
SPROUT_CONSTEXPR merge_iterator(merge_iterator<U, V, W> const& it)
|
|
: current1(it.base()), las1(it.last1())
|
|
, current2(it.base2()), las2(it.last2())
|
|
, comp(it.compare())
|
|
, in_left(it.is_in_left())
|
|
{}
|
|
template<typename U, typename V, typename W>
|
|
SPROUT_CXX14_CONSTEXPR merge_iterator& operator=(merge_iterator<U, V, W> const& it) {
|
|
merge_iterator temp(it);
|
|
temp.swap(*this);
|
|
return *this;
|
|
}
|
|
SPROUT_CONSTEXPR iterator_type base() const {
|
|
return current1;
|
|
}
|
|
SPROUT_CONSTEXPR iterator_type last1() const {
|
|
return las1;
|
|
}
|
|
SPROUT_CONSTEXPR iterator2_type base2() const {
|
|
return current2;
|
|
}
|
|
SPROUT_CONSTEXPR iterator2_type last2() const {
|
|
return las2;
|
|
}
|
|
SPROUT_CONSTEXPR Compare compare() const {
|
|
return comp;
|
|
}
|
|
SPROUT_CONSTEXPR bool is_in_left() const {
|
|
return in_left;
|
|
}
|
|
SPROUT_CONSTEXPR reference operator*() const {
|
|
return is_in_left() ? *current1 : *current2;
|
|
}
|
|
SPROUT_CONSTEXPR pointer operator->() const {
|
|
return &*(*this);
|
|
}
|
|
SPROUT_CXX14_CONSTEXPR merge_iterator& operator++() {
|
|
if (current1 != las1) {
|
|
if (current2 != las2) {
|
|
if (comp(*current2, *current1)) {
|
|
++current2;
|
|
} else {
|
|
++current1;
|
|
}
|
|
} else {
|
|
++current1;
|
|
}
|
|
} else if (current2 != las2) {
|
|
++current2;
|
|
}
|
|
in_left = check_in_left(current1, las1, current2, las2, comp);
|
|
return *this;
|
|
}
|
|
SPROUT_CXX14_CONSTEXPR merge_iterator operator++(int) {
|
|
merge_iterator result(*this);
|
|
if (current1 != las1) {
|
|
if (current2 != las2) {
|
|
if (comp(*current2, *current1)) {
|
|
++current2;
|
|
} else {
|
|
++current1;
|
|
}
|
|
} else {
|
|
++current1;
|
|
}
|
|
} else if (current2 != las2) {
|
|
++current2;
|
|
}
|
|
in_left = check_in_left(current1, las1, current2, las2, comp);
|
|
return result;
|
|
}
|
|
SPROUT_CONSTEXPR merge_iterator next() const {
|
|
return current1 != las1
|
|
? current2 != las2
|
|
? comp(*current2, *current1)
|
|
? merge_iterator(current1, las1, sprout::next(current2), las2, comp)
|
|
: merge_iterator(sprout::next(current1), las1, current2, las2, comp)
|
|
: merge_iterator(sprout::next(current1), las1, current2, las2, comp)
|
|
: current2 != las2
|
|
? merge_iterator(current1, las1, sprout::next(current2), las2, comp)
|
|
: *this
|
|
;
|
|
}
|
|
SPROUT_CXX14_CONSTEXPR void swap(merge_iterator& other)
|
|
SPROUT_NOEXCEPT_IF(
|
|
SPROUT_NOEXCEPT_EXPR(sprout::swap(current1, other.current1))
|
|
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(las1, other.las1))
|
|
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(current2, other.current2))
|
|
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(las2, other.las2))
|
|
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(comp, other.comp))
|
|
&& SPROUT_NOEXCEPT_EXPR(sprout::swap(in_left, other.in_left))
|
|
)
|
|
{
|
|
sprout::swap(current1, other.current1);
|
|
sprout::swap(las1, other.las1);
|
|
sprout::swap(current2, other.current2);
|
|
sprout::swap(las2, other.las2);
|
|
sprout::swap(comp, other.comp);
|
|
sprout::swap(in_left, other.in_left);
|
|
}
|
|
};
|
|
|
|
template<
|
|
typename LIterator1, typename RIterator1, typename Compare1,
|
|
typename LIterator2, typename RIterator2, typename Compare2
|
|
>
|
|
inline SPROUT_CONSTEXPR bool operator==(
|
|
sprout::merge_iterator<LIterator1, RIterator1, Compare1> const& lhs,
|
|
sprout::merge_iterator<LIterator2, RIterator2, Compare2> const& rhs
|
|
)
|
|
{
|
|
return lhs.base() == rhs.base() && lhs.base2() == rhs.base2();
|
|
}
|
|
template<
|
|
typename LIterator1, typename RIterator1, typename Compare1,
|
|
typename LIterator2, typename RIterator2, typename Compare2
|
|
>
|
|
inline SPROUT_CONSTEXPR bool operator!=(
|
|
sprout::merge_iterator<LIterator1, RIterator1, Compare1> const& lhs,
|
|
sprout::merge_iterator<LIterator2, RIterator2, Compare2> const& rhs
|
|
)
|
|
{
|
|
return !(lhs == rhs);
|
|
}
|
|
|
|
//
|
|
// make_merge_iterator
|
|
//
|
|
template<typename LIterator, typename RIterator, typename Compare>
|
|
inline SPROUT_CONSTEXPR sprout::merge_iterator<LIterator, RIterator, Compare>
|
|
make_merge_iterator(LIterator it1, LIterator las1, RIterator it2, RIterator las2, Compare comp) {
|
|
return sprout::merge_iterator<LIterator, RIterator, Compare>(it1, las1, it2, las2, comp);
|
|
}
|
|
template<typename LIterator, typename RIterator>
|
|
inline SPROUT_CONSTEXPR sprout::merge_iterator<LIterator, RIterator>
|
|
make_merge_iterator(LIterator it1, LIterator las1, RIterator it2, RIterator las2) {
|
|
return sprout::merge_iterator<LIterator, RIterator>(it1, las1, it2, las2);
|
|
}
|
|
|
|
//
|
|
// swap
|
|
//
|
|
template<typename LIterator, typename RIterator, typename Compare>
|
|
inline SPROUT_CXX14_CONSTEXPR void
|
|
swap(
|
|
sprout::merge_iterator<LIterator, RIterator, Compare>& lhs,
|
|
sprout::merge_iterator<LIterator, RIterator, Compare>& rhs
|
|
)
|
|
SPROUT_NOEXCEPT_IF_EXPR(lhs.swap(rhs))
|
|
{
|
|
lhs.swap(rhs);
|
|
}
|
|
|
|
//
|
|
// iterator_next
|
|
//
|
|
template<typename LIterator, typename RIterator, typename Compare>
|
|
inline SPROUT_CONSTEXPR sprout::merge_iterator<LIterator, RIterator, Compare>
|
|
iterator_next(sprout::merge_iterator<LIterator, RIterator, Compare> const& it) {
|
|
return it.next();
|
|
}
|
|
} // namespace sprout
|
|
|
|
#endif // #ifndef SPROUT_ITERATOR_MERGE_ITERATOR_HPP
|