Removed useless code [#CLICKHOUSE-31].

dbms/src/Functions/FunctionsArray.cpp

@@ -15,6 +15,7 @@
 #include <Interpreters/AggregationCommon.h>
 #include <Columns/ColumnTuple.h>
 #include <Columns/ColumnAggregateFunction.h>
+#include <boost/iterator/counting_iterator.hpp>
 #include <tuple>
 #include <array>
 
@@ -2356,7 +2357,7 @@ bool FunctionRange::executeInternal(Block & block, const IColumn * const arg, co
         IColumn::Offset_t offset{};
         for (const auto i : ext::range(0, in->size()))
         {
-            std::copy(ext::make_range_iterator(T{}), ext::make_range_iterator(in_data[i]), &out_data[offset]);
+            std::copy(boost::counting_iterator(T{}), boost::counting_iterator(in_data[i]), &out_data[offset]);
             offset += in_data[i];
             out_offsets[i] = offset;
         }
@@ -2392,7 +2393,7 @@ bool FunctionRange::executeInternal(Block & block, const IColumn * const arg, co
         IColumn::Offset_t offset{};
         for (const auto i : ext::range(0, in->size()))
         {
-            std::copy(ext::make_range_iterator(T{}), ext::make_range_iterator(in_data), &out_data[offset]);
+            std::copy(boost::counting_iterator(T{}), boost::counting_iterator(in_data), &out_data[offset]);
             offset += in_data;
             out_offsets[i] = offset;
         }

libs/libcommon/include/ext/make_array_n.h

@@ -11,7 +11,6 @@
   */
 namespace ext
 {
-
     namespace detail
     {
 

libs/libcommon/include/ext/range.h

@@ -14,53 +14,32 @@ namespace ext
     template <typename T>
     using range_iterator = boost::counting_iterator<T>;
 
-    template <typename T>
-    using reverse_range_iterator = std::reverse_iterator<range_iterator<T>>;
-
     /** \brief Range-based for loop adapter for (reverse_)range_iterator.
-     *  By and large should be in conjunction with ext::range and ext::reverse_range. */
-    template <typename T, bool forward>
+      *  By and large should be in conjunction with ext::range and ext::reverse_range.
+      */
+    template <typename T>
     struct range_wrapper
     {
         using value_type = typename std::remove_reference<T>::type;
-        using range_iterator_t = ext::range_iterator<value_type>;
-        using iterator = typename std::conditional<forward,
-            range_iterator_t,
-            ext::reverse_range_iterator<value_type>>::type;
+        using iterator = range_iterator<value_type>;
 
-        value_type begin_, end_;
+        value_type begin_;
+        value_type end_;
 
-        iterator begin() const { return iterator(range_iterator_t{begin_}); }
-        iterator end() const { return iterator(range_iterator_t{end_}); }
+        iterator begin() const { return iterator(begin_); }
+        iterator end() const { return iterator(end_); }
     };
 
     /** \brief Constructs range_wrapper for forward-iteration over [begin, end) in range-based for loop.
      *  Usage example:
      *      for (const auto i : ext::range(0, 4)) print(i);
      *  Output:
-     *      0 1 2 3 */
-    template<typename T1, typename T2>
-    inline ext::range_wrapper<typename std::common_type<T1, T2>::type, true> range(T1 begin, T2 end)
+     *      0 1 2 3
+     */
+    template <typename T1, typename T2>
+    inline range_wrapper<typename std::common_type<T1, T2>::type> range(T1 begin, T2 end)
     {
         using common_type = typename std::common_type<T1, T2>::type;
         return { static_cast<common_type>(begin), static_cast<common_type>(end) };
     }
-
-    /** \brief Constructs range_wrapper for backward-iteration over [begin, end) in range-based for loop.
-     *  Usage example:
-     *      for (const auto i : ext::reverse_range(0, 4)) print(i);
-     *  Output:
-     *      3 2 1 0 */
-    template<typename T1, typename T2>
-    inline ext::range_wrapper<typename std::common_type<T1, T2>::type, false> reverse_range(T1 begin, T2 end)
-    {
-        using common_type = typename std::common_type<T1, T2>::type;
-        return { static_cast<common_type>(end), static_cast<common_type>(begin) };
-    }
-
-    template<typename T>
-    inline ext::range_iterator<T> make_range_iterator(const T value)
-    {
-        return { value };
-    }
 }