Intermediate changes

commit_hash:1f5f18fdf0f2495984459d943dd860d4ae2c6202

1 files changed, 46 insertions, 13 deletions

diff --git a/library/cpp/containers/dense_hash/dense_hash.h b/library/cpp/containers/dense_hash/dense_hash.h
index b5feb16eefb..a3ada43ff87 100644
--- a/library/cpp/containers/dense_hash/dense_hash.h
+++ b/library/cpp/containers/dense_hash/dense_hash.h
@@ -10,6 +10,8 @@
 #include <util/str_stl.h>
 #include <util/ysaveload.h>
 
+#include <iterator>
+
 /*
  * There are 2 classes in this file:
  *   - TDenseHash - analog of THashMap
@@ -38,8 +40,8 @@ private:
         template <class THash2, class TVal2>
         friend class TIteratorBase;
 
-        THash* Hash;
-        size_t Idx;
+        THash* Hash = nullptr;
+        size_t Idx = 0;
 
         // used only to implement end()
         TIteratorBase(THash* hash, size_t initIdx)
@@ -49,6 +51,15 @@ private:
         }
 
     public:
+        using iterator_concept = std::forward_iterator_tag;
+        using iterator_category = std::forward_iterator_tag;
+        using value_type = std::remove_const_t<TVal>;
+        using difference_type = std::ptrdiff_t;
+        using pointer = TVal*;
+        using reference = TVal&;
+
+        TIteratorBase() = default;
+
         TIteratorBase(THash& hash)
             : Hash(&hash)
             , Idx(0)
@@ -67,10 +78,6 @@ private:
 
         TIteratorBase(const TIteratorBase&) = default;
 
-        static TIteratorBase CreateEmpty() {
-            return TIteratorBase(nullptr, 0);
-        }
-
         TIteratorBase& operator=(const TIteratorBase&) = default;
 
         void Next() {
@@ -85,15 +92,17 @@ private:
             return *this;
         }
 
-        TVal& operator*() {
-            return Hash->Buckets[Idx];
+        TIteratorBase operator++(int) {
+            TIteratorBase tmp = *this;
+            Next();
+            return tmp;
         }
 
-        TVal* operator->() {
-            return &Hash->Buckets[Idx];
+        TVal& operator*() const {
+            return Hash->Buckets[Idx];
         }
 
-        const TVal* operator->() const {
+        TVal* operator->() const {
             return &Hash->Buckets[Idx];
         }
 
@@ -128,6 +137,9 @@ public:
     using iterator = TIteratorBase<TDenseHash, value_type>;
     using const_iterator = TIteratorBase<const TDenseHash, const value_type>;
 
+   static_assert(std::forward_iterator<iterator>);
+   static_assert(std::forward_iterator<const_iterator>);
+
 public:
     TDenseHash(const key_type& emptyMarker = key_type{}, size_type initSize = 0)
         : EmptyMarker(emptyMarker)
@@ -526,8 +538,8 @@ private:
     class TIteratorBase {
         friend class TDenseHashSet;
 
-        THash* Hash;
-        size_t Idx;
+        THash* Hash = nullptr;
+        size_t Idx = 0;
 
         // used only to implement end()
         TIteratorBase(THash* hash, size_t initIdx)
@@ -537,6 +549,15 @@ private:
         }
 
     public:
+        using iterator_concept = std::forward_iterator_tag;
+        using iterator_category = std::forward_iterator_tag;
+        using value_type = TKey;
+        using difference_type = std::ptrdiff_t;
+        using pointer = const TKey*;
+        using reference = const TKey&;
+
+        TIteratorBase() = default;
+
         TIteratorBase(THash& hash)
             : Hash(&hash)
             , Idx(0)
@@ -558,6 +579,12 @@ private:
             return *this;
         }
 
+        TIteratorBase operator++(int) {
+            TIteratorBase tmp = *this;
+            Next();
+            return tmp;
+        }
+
         bool Initialized() const {
             return Hash != nullptr;
         }
@@ -570,6 +597,10 @@ private:
             return Key();
         }
 
+        const TKey* operator->() const {
+            return &Hash->Buckets[Idx];
+        }
+
         const TKey& Key() const {
             return Hash->Buckets[Idx];
         }
@@ -587,6 +618,8 @@ private:
 public:
     typedef TIteratorBase<const TDenseHashSet> TConstIterator;
 
+   static_assert(std::forward_iterator<TConstIterator>);
+
     TConstIterator begin() const {
         return TConstIterator(*this);
     }