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diff --git a/boost/poly_collection/detail/stride_iterator.hpp b/boost/poly_collection/detail/stride_iterator.hpp
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+++ b/boost/poly_collection/detail/stride_iterator.hpp
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+/* Copyright 2016 Joaquin M Lopez Munoz.
+ * Distributed under the Boost Software License, Version 1.0.
+ * (See accompanying file LICENSE_1_0.txt or copy at
+ * http://www.boost.org/LICENSE_1_0.txt)
+ *
+ * See http://www.boost.org/libs/poly_collection for library home page.
+ */
+
+#ifndef BOOST_POLY_COLLECTION_DETAIL_STRIDE_ITERATOR_HPP
+#define BOOST_POLY_COLLECTION_DETAIL_STRIDE_ITERATOR_HPP
+
+#if defined(_MSC_VER)
+#pragma once
+#endif
+
+#include <boost/iterator/iterator_facade.hpp>
+#include <type_traits>
+
+namespace boost{
+
+namespace poly_collection{
+
+namespace detail{
+
+/* random-access iterator to Value elements laid out stride *chars* apart */
+
+template<typename Value>
+class stride_iterator:
+  public boost::iterator_facade<
+    stride_iterator<Value>,
+    Value,
+    boost::random_access_traversal_tag
+  >
+{
+public:
+  stride_iterator()=default;
+  stride_iterator(Value* p,std::size_t stride)noexcept:p{p},stride_{stride}{}
+  stride_iterator(const stride_iterator&)=default;
+  stride_iterator& operator=(const stride_iterator&)=default;
+
+  template<
+    typename NonConstValue,
+    typename std::enable_if<
+      std::is_same<Value,const NonConstValue>::value>::type* =nullptr
+  >
+  stride_iterator(const stride_iterator<NonConstValue>& x)noexcept:
+    p{x.p},stride_{x.stride_}{}
+
+  template<
+    typename NonConstValue,
+    typename std::enable_if<
+      std::is_same<Value,const NonConstValue>::value>::type* =nullptr
+  >
+  stride_iterator& operator=(const stride_iterator<NonConstValue>& x)noexcept
+  {
+    p=x.p;stride_=x.stride_;
+    return *this;
+  }
+
+  /* interoperability with [Derived]Value* */
+
+  stride_iterator& operator=(Value* p_)noexcept{p=p_;return *this;}
+  operator Value*()const noexcept{return p;}
+
+  template<
+    typename DerivedValue,
+    typename std::enable_if<
+      std::is_base_of<Value,DerivedValue>::value&&
+      (std::is_const<Value>::value||!std::is_const<DerivedValue>::value)
+    >::type* =nullptr
+  >
+  explicit stride_iterator(DerivedValue* x)noexcept:
+    p{x},stride_{sizeof(DerivedValue)}{}
+
+  template<
+    typename DerivedValue,
+    typename std::enable_if<
+      std::is_base_of<Value,DerivedValue>::value&&
+      (!std::is_const<Value>::value||std::is_const<DerivedValue>::value)
+    >::type* =nullptr
+  >
+  explicit operator DerivedValue*()const noexcept
+  {return static_cast<DerivedValue*>(p);}
+
+  std::size_t stride()const noexcept{return stride_;}
+
+private:
+  template<typename>
+  friend class stride_iterator;
+
+  using char_pointer=typename std::conditional<
+    std::is_const<Value>::value,
+    const char*,
+    char*
+  >::type;
+
+  static char_pointer char_ptr(Value* p)noexcept
+    {return reinterpret_cast<char_pointer>(p);}
+  static Value*       value_ptr(char_pointer p)noexcept
+    {return reinterpret_cast<Value*>(p);}
+
+  friend class boost::iterator_core_access;
+
+  Value& dereference()const noexcept{return *p;}
+  bool equal(const stride_iterator& x)const noexcept{return p==x.p;}
+  void increment()noexcept{p=value_ptr(char_ptr(p)+stride_);}
+  void decrement()noexcept{p=value_ptr(char_ptr(p)-stride_);}
+  template<typename Integral>
+  void advance(Integral n)noexcept{p=value_ptr(char_ptr(p)+n*stride_);}
+  std::ptrdiff_t distance_to(const stride_iterator& x)const noexcept
+    {return (char_ptr(x.p)-char_ptr(p))/stride_;}          
+
+  Value*      p;
+  std::size_t stride_;
+};
+
+} /* namespace poly_collection::detail */
+
+} /* namespace poly_collection */
+
+} /* namespace boost */
+
+#endif