filter_view::iterator : iter_moveとiter_swapを追加 #713

Author: faithandbrave

GLOBAL_QUALIFY_LIST.txt

@@ -149,6 +149,7 @@
     * indirect_binary_predicate[link /reference/iterator/indirect_binary_predicate.md]
     * indirect_unary_predicate[link /reference/iterator/indirect_unary_predicate.md]
     * indirectly_comparable[link /reference/iterator/indirectly_comparable.md]
+    * indirectly_swappable[link /reference/iterator/indirectly_swappable.md]
     * input_iterator[link /reference/iterator/input_iterator.md]
     * iterator_traits[link /reference/iterator/iterator_traits.md]
     * iter_difference_t[link /reference/iterator/iter_difference_t.md]
@@ -158,11 +159,14 @@
     * projected[link /reference/iterator/projected.md]
     * projected_value_t[link /reference/iterator/projected_value_t.md]
     * random_access_iterator[link /reference/iterator/random_access_iterator.md]
+    * ranges::iter_move[link /reference/iterator/iter_move.md]
+    * ranges::iter_swap[link /reference/iterator/iter_swap.md]
     * sentinel_for[link /reference/iterator/sentinel_for.md]
     * std::back_inserter[link /reference/iterator/back_inserter.md]
     * std::begin[link /reference/iterator/begin.md]
     * std::distance[link /reference/iterator/distance.md]
     * std::end[link /reference/iterator/end.md]
+    * std::next[link /reference/iterator/next.md]
     * std::ostream_iterator[link /reference/iterator/ostream_iterator.md]
 * <latch>[link /reference/latch.md]
 * <limits>[link /reference/limits.md]

reference/ranges/filter_view/iterator.md

@@ -55,8 +55,8 @@ namespace std::ranges {
 
 | 名前                                     | 説明                   | 対応バージョン |
 |------------------------------------------|------------------------|----------------|
-| [`iter_move`](iterator/iter_move.md.nolink)     | イテレータの要素の移動 | C++20          |
-| [`iter_swap`](iterator/iter_swap.md.nolink)     | イテレータの要素の交換 | C++20          |
+| [`iter_move`](iterator/iter_move.md)     | イテレータの要素の移動 | C++20          |
+| [`iter_swap`](iterator/iter_swap.md)     | イテレータの要素の交換 | C++20          |
 
 ### 比較演算子
 

reference/ranges/filter_view/iterator/iter_move.md

@@ -0,0 +1,65 @@
+# iter_move
+* ranges[meta header]
+* std::ranges[meta namespace]
+* filter_view::iterator[meta class]
+* function[meta id-type]
+* cpp20[meta cpp]
+
+```cpp
+friend constexpr range_rvalue_reference_t<V>
+  iter_move(const iterator& i)
+    noexcept(noexcept(ranges::iter_move(i.current_))); // (1) C++20
+```
+
+## 概要
+イテレータの要素を移動する。
+
+
+## 効果
+以下と等価：
+
+```cpp
+return ranges::iter_move(i.current_);
+```
+
+
+## 例
+```cpp example
+#include <iostream>
+#include <ranges>
+#include <vector>
+#include <string>
+
+int main() {
+  std::vector<std::string> v = {"apple", "banana", "cherry", "date"};
+  auto is_long = [](const std::string& s) { return s.size() > 5; };
+
+  std::ranges::filter_view fv{v, is_long};
+  auto it = fv.begin();
+
+  // iter_moveで要素をムーブ
+  std::string s = iter_move(it);
+  std::cout << s << std::endl; // banana
+
+  // ムーブ後の元要素は空になる
+  std::cout << std::boolalpha << v[1].empty() << std::endl; // true
+}
+```
+* iter_move[color ff0000]
+
+### 出力
+
+```
+banana
+true
+```
+
+## バージョン
+### 言語
+- C++20
+
+### 処理系
+- [Clang](/implementation.md#clang): 13.0.0 [mark verified]
+- [GCC](/implementation.md#gcc): 10.1.0 [mark verified]
+- [ICC](/implementation.md#icc): ?
+- [Visual C++](/implementation.md#visual_cpp): 2019 Update 10 [mark verified]

reference/ranges/filter_view/iterator/iter_swap.md

@@ -0,0 +1,63 @@
+# iter_swap
+* ranges[meta header]
+* std::ranges[meta namespace]
+* filter_view::iterator[meta class]
+* function[meta id-type]
+* cpp20[meta cpp]
+
+```cpp
+friend constexpr void
+  iter_swap(const iterator& x, const iterator& y)
+    noexcept(noexcept(ranges::iter_swap(x.current_, y.current_)))
+    requires indirectly_swappable<iterator_t<V>>; // (1) C++20
+```
+
+## 概要
+イテレータの要素を交換する。
+
+
+## 効果
+以下と等価：
+
+```cpp
+return ranges::iter_swap(x.current_, y.current_);
+```
+
+
+## 例
+```cpp example
+#include <vector>
+#include <iostream>
+#include <ranges>
+
+int main() {
+  std::vector<int> v = {1, 2, 3, 4, 5, 6};
+  auto is_even = [](int x) { return x % 2 == 0; };
+  std::ranges::filter_view fv{v, is_even};
+
+  auto it1 = fv.begin();            // v[1] を指す
+  auto it2 = std::next(fv.begin()); // v[3] を指す
+
+  std::cout << v[1] << ", " << v[3] << std::endl; // 2, 4
+  iter_swap(it1, it2);
+  std::cout << v[1] << ", " << v[3] << std::endl; // 4, 2
+}
+```
+* iter_swap[color ff0000]
+
+### 出力
+
+```
+2, 4
+4, 2
+```
+
+## バージョン
+### 言語
+- C++20
+
+### 処理系
+- [Clang](/implementation.md#clang): 13.0.0 [mark verified]
+- [GCC](/implementation.md#gcc): 10.1.0 [mark verified]
+- [ICC](/implementation.md#icc): ?
+- [Visual C++](/implementation.md#visual_cpp): 2019 Update 10 [mark verified]