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diff --git a/boost/histogram/axis/iterator.hpp b/boost/histogram/axis/iterator.hpp
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+// Copyright 2015-2017 Hans Dembinski
+//
+// 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)
+
+#ifndef BOOST_HISTOGRAM_AXIS_ITERATOR_HPP
+#define BOOST_HISTOGRAM_AXIS_ITERATOR_HPP
+
+#include <boost/histogram/axis/interval_view.hpp>
+#include <boost/histogram/detail/meta.hpp>
+#include <boost/iterator/iterator_adaptor.hpp>
+#include <boost/iterator/reverse_iterator.hpp>
+
+namespace boost {
+namespace histogram {
+namespace axis {
+
+template <typename Axis>
+class iterator
+    : public boost::iterator_adaptor<iterator<Axis>, int,
+                                     decltype(std::declval<const Axis&>().bin(0)),
+                                     std::random_access_iterator_tag,
+                                     decltype(std::declval<const Axis&>().bin(0)), int> {
+public:
+  explicit iterator(const Axis& axis, int idx)
+      : iterator::iterator_adaptor_(idx), axis_(axis) {}
+
+protected:
+  bool equal(const iterator& other) const noexcept {
+    return &axis_ == &other.axis_ && this->base() == other.base();
+  }
+
+  decltype(auto) dereference() const { return axis_.bin(this->base()); }
+
+private:
+  const Axis& axis_;
+  friend class boost::iterator_core_access;
+};
+
+/// Uses CRTP to inject iterator logic into Derived.
+template <typename Derived>
+class iterator_mixin {
+public:
+  using const_iterator = iterator<Derived>;
+  using const_reverse_iterator = boost::reverse_iterator<const_iterator>;
+
+  /// Bin iterator to beginning of the axis (read-only).
+  const_iterator begin() const noexcept {
+    return const_iterator(*static_cast<const Derived*>(this), 0);
+  }
+
+  /// Bin iterator to the end of the axis (read-only).
+  const_iterator end() const noexcept {
+    return const_iterator(*static_cast<const Derived*>(this),
+                          static_cast<const Derived*>(this)->size());
+  }
+
+  /// Reverse bin iterator to the last entry of the axis (read-only).
+  const_reverse_iterator rbegin() const noexcept {
+    return boost::make_reverse_iterator(end());
+  }
+
+  /// Reverse bin iterator to the end (read-only).
+  const_reverse_iterator rend() const noexcept {
+    return boost::make_reverse_iterator(begin());
+  }
+};
+
+} // namespace axis
+} // namespace histogram
+} // namespace boost
+
+#endif