[indexer] StringSet.

1 files changed, 47 insertions, 4 deletions

diff --git a/indexer/string_slice.hpp b/indexer/string_slice.hpp
index 510cdbe8cb..38d2a1230c 100644
--- a/indexer/string_slice.hpp
+++ b/indexer/string_slice.hpp
@@ -22,10 +22,7 @@ public:
 class NoPrefixStringSlice : public StringSliceBase
 {
 public:
-  NoPrefixStringSlice(vector<TString> const & strings)
-      : m_strings(strings)
-  {
-  }
+  NoPrefixStringSlice(vector<TString> const & strings) : m_strings(strings) {}
 
   virtual TString const & Get(size_t i) const override { return m_strings[i]; }
   virtual size_t Size() const override { return m_strings.size(); }
@@ -33,4 +30,50 @@ public:
 private:
   vector<TString> const & m_strings;
 };
+
+// Allows to iterate over space-separated strings in StringSliceBase.
+class JoinIterator
+{
+public:
+  using difference_type = ptrdiff_t;
+  using value_type = strings::UniChar;
+  using pointer = strings::UniChar *;
+  using reference = strings::UniChar &;
+  using iterator_category = std::forward_iterator_tag;
+
+  static JoinIterator Begin(StringSliceBase const & slice);
+  static JoinIterator End(StringSliceBase const & slice);
+
+  inline bool operator==(JoinIterator const & rhs) const
+  {
+    return &m_slice == &rhs.m_slice && m_string == rhs.m_string && m_offset == rhs.m_offset;
+  }
+
+  inline bool operator!=(JoinIterator const & rhs) const { return !(*this == rhs); }
+
+  inline strings::UniChar operator*() const { return GetChar(m_string, m_offset); }
+
+  JoinIterator & operator++();
+
+private:
+  enum class Position
+  {
+    Begin,
+    End
+  };
+
+  JoinIterator(StringSliceBase const & slice, Position position);
+
+  void Normalize();
+
+  size_t GetSize(size_t string) const;
+
+  inline size_t GetMaxSize() const { return m_slice.Size() == 0 ? 0 : m_slice.Size() * 2 - 1; }
+
+  strings::UniChar GetChar(size_t string, size_t offset) const;
+
+  StringSliceBase const & m_slice;
+  size_t m_string;
+  size_t m_offset;
+};
 }  // namespace search