C++20 コンテナの非メンバ関数erase/erase_if : 戻り値改善の仕様変更を適用

reference/deque/deque/erase_free.md

@@ -19,10 +19,14 @@ namespace std {
 以下と等価：
 
 ```
-c.erase(remove(c.begin(), c.end(), value), c.end());
+auto it = remove(c.begin(), c.end(), value);
+auto r = distance(it, c.end());
+c.erase(it, c.end());
+return r;
 ```
 * c.erase[link erase.md]
 * remove[link /reference/algorithm/remove.md]
+* distance[link /reference/iterator/distance.md]
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 
@@ -68,4 +72,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/deque/deque/erase_if_free.md

@@ -19,10 +19,14 @@ namespace std {
 以下と等価：
 
 ```
-c.erase(remove_if(c.begin(), c.end(), pred), c.end());
+auto it = remove_if(c.begin(), c.end(), pred);
+auto r = distance(it, c.end());
+c.erase(it, c.end());
+return r;
 ```
 * c.erase[link erase.md]
 * remove_if[link /reference/algorithm/remove_if.md]
+* distance[link /reference/iterator/distance.md]
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 
@@ -68,4 +72,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/forward_list/forward_list/erase_free.md

@@ -65,4 +65,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/forward_list/forward_list/erase_if_free.md

@@ -65,4 +65,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/list/list/erase_free.md

@@ -65,4 +65,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/list/list/erase_if_free.md

@@ -65,4 +65,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/map/map/erase_if_free.md

@@ -7,7 +7,8 @@
 ```cpp
 namespace std {
   template <class Key, class T, class Compare, class Allocator, class Predicate>
-  void erase_if(map<Key, T, Compare, Allocator>& c, Predicate pred);
+  typename map<Key, T, Compare, Allocator>::size_type
+    erase_if(map<Key, T, Compare, Allocator>& c, Predicate pred);
 }
 ```
 
@@ -21,21 +22,24 @@ namespace std {
 以下と等価：
 
 ```
+auto original_size = c.size();
 for (auto i = c.begin(), last = c.end(); i != last;) {
   if (pred(*i)) {
     i = c.erase(i);
   } else {
     ++i;
   }
 }
+return original_size - c.size();
 ```
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 * c.erase[link erase.md]
+* c.size()[link size.md]
 
 
 ## 戻り値
-なし
+削除した要素数を返す。
 
 
 ## 例
@@ -78,4 +82,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/map/multimap/erase_if_free.md

@@ -7,7 +7,8 @@
 ```cpp
 namespace std {
   template <class Key, class T, class Compare, class Allocator, class Predicate>
-  void erase_if(multimap<Key, T, Compare, Allocator>& c, Predicate pred);
+  typename multimap<Key, T, Compare, Allocator>::size_type
+    erase_if(multimap<Key, T, Compare, Allocator>& c, Predicate pred);
 }
 ```
 
@@ -21,21 +22,24 @@ namespace std {
 以下と等価：
 
 ```
+auto original_size = c.size();
 for (auto i = c.begin(), last = c.end(); i != last;) {
   if (pred(*i)) {
     i = c.erase(i);
   } else {
     ++i;
   }
 }
+return original_size - c.size();
 ```
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 * c.erase[link erase.md]
+* c.size()[link size.md]
 
 
 ## 戻り値
-なし
+削除した要素数を返す。
 
 
 ## 例
@@ -78,4 +82,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/set/multiset/erase_if_free.md

@@ -7,7 +7,8 @@
 ```cpp
 namespace std {
   template <class Key, class Compare, class Allocator, class Predicate>
-  void erase_if(multiset<Key, Compare, Allocator>& c, Predicate pred);
+  typename multiset<Key, Compare, Allocator>::size_type
+    erase_if(multiset<Key, Compare, Allocator>& c, Predicate pred);
 }
 ```
 
@@ -19,21 +20,24 @@ namespace std {
 以下と等価：
 
 ```
+auto original_size = c.size();
 for (auto i = c.begin(), last = c.end(); i != last;) {
   if (pred(*i)) {
     i = c.erase(i);
   } else {
     ++i;
   }
 }
+return original_size - c.size();
 ```
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 * c.erase[link erase.md]
+* c.size()[link size.md]
 
 
 ## 戻り値
-なし
+削除した要素数を返す。
 
 
 ## 例
@@ -72,4 +76,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/set/set/erase_if_free.md

@@ -7,7 +7,8 @@
 ```cpp
 namespace std {
   template <class Key, class Compare, class Allocator, class Predicate>
-  void erase_if(set<Key, Compare, Allocator>& c, Predicate pred);
+  typename set<Key, Compare, Allocator>::size_type
+    erase_if(set<Key, Compare, Allocator>& c, Predicate pred);
 }
 ```
 
@@ -19,21 +20,24 @@ namespace std {
 以下と等価：
 
 ```
+auto original_size = c.size();
 for (auto i = c.begin(), last = c.end(); i != last;) {
   if (pred(*i)) {
     i = c.erase(i);
   } else {
     ++i;
   }
 }
+return original_size - c.size();
 ```
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 * c.erase[link erase.md]
+* c.size()[link size.md]
 
 
 ## 戻り値
-なし
+削除した要素数を返す。
 
 
 ## 例
@@ -72,4 +76,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/string/basic_string/erase_free.md

@@ -19,10 +19,14 @@ namespace std {
 以下と等価：
 
 ```
-c.erase(remove(c.begin(), c.end(), value), c.end());
+auto it = remove(c.begin(), c.end(), value);
+auto r = distance(it, c.end());
+c.erase(it, c.end());
+return r;
 ```
 * c.erase[link erase.md]
 * remove[link /reference/algorithm/remove.md]
+* distance[link /reference/iterator/distance.md]
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 
@@ -64,4 +68,5 @@ HelloWorld
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/string/basic_string/erase_if_free.md

@@ -19,10 +19,14 @@ namespace std {
 以下と等価：
 
 ```
-c.erase(remove_if(c.begin(), c.end(), pred), c.end());
+auto it = remove_if(c.begin(), c.end(), pred);
+auto r = distance(it, c.end());
+c.erase(it, c.end());
+return r;
 ```
 * c.erase[link erase.md]
 * remove_if[link /reference/algorithm/remove_if.md]
+* distance[link /reference/iterator/distance.md]
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 
@@ -64,4 +68,5 @@ HelloWorld
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/unordered_map/unordered_map/erase_if_free.md

@@ -7,7 +7,8 @@
 ```cpp
 namespace std {
   template <class K, class T, class H, class P, class A, class Predicate>
-  void erase_if(unordered_map<K, T, H, P, A>& c, Predicate pred);
+  typename unordered_map<K, T, H, P, A>::size_type
+    erase_if(unordered_map<K, T, H, P, A>& c, Predicate pred);
 }
 ```
 
@@ -21,21 +22,24 @@ namespace std {
 以下と等価：
 
 ```
+auto original_size = c.size();
 for (auto i = c.begin(), last = c.end(); i != last;) {
   if (pred(*i)) {
     i = c.erase(i);
   } else {
     ++i;
   }
 }
+return original_size - c.size();
 ```
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 * c.erase[link erase.md]
+* c.size()[link size.md]
 
 
 ## 戻り値
-なし
+削除した要素数を返す。
 
 
 ## 例
@@ -78,4 +82,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)

reference/unordered_map/unordered_multimap/erase_if_free.md

@@ -7,7 +7,8 @@
 ```cpp
 namespace std {
   template <class K, class T, class H, class P, class A, class Predicate>
-  void erase_if(unordered_multimap<K, T, H, P, A>& c, Predicate pred);
+  typename unordered_multimap<K, T, H, P, A>::size_type
+    erase_if(unordered_multimap<K, T, H, P, A>& c, Predicate pred);
 }
 ```
 
@@ -21,21 +22,24 @@ namespace std {
 以下と等価：
 
 ```
+auto original_size = c.size();
 for (auto i = c.begin(), last = c.end(); i != last;) {
   if (pred(*i)) {
     i = c.erase(i);
   } else {
     ++i;
   }
 }
+return original_size - c.size();
 ```
 * c.begin()[link begin.md]
 * c.end()[link end.md]
 * c.erase[link erase.md]
+* c.size()[link size.md]
 
 
 ## 戻り値
-なし
+削除した要素数を返す。
 
 
 ## 例
@@ -79,4 +83,5 @@ int main()
 
 
 ## 参照
-- [P1209R0 | Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [P1209R0 Adopt consistent container erasure from Library Fundamentals 2](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1209r0.html)
+- [R1115R3 Improving the Return Value of Erase-Like Algorithms II: Free `erase`/`erase_if`](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1115r3.pdf)