diff --git a/adapter.hpp b/adapter.hpp
index 3d4f4e63..87b929b9 100644
--- a/adapter.hpp
+++ b/adapter.hpp
@@ -192,20 +192,16 @@ namespace cruft::adapter {
         /// corresponds to the underlying iterator::value_type when
         /// dereferenced.
         template <size_t I, typename IteratorT>
-        struct scalar : public std::iterator<
-            typename std::iterator_traits<IteratorT>::iterator_category,
-            typename std::tuple_element<
+        struct scalar {
+        public:
+            using iterator_category = typename std::iterator_traits<IteratorT>::iterator_category;
+            using value_type = typename std::tuple_element<
                 I,
                 typename std::iterator_traits<
                     IteratorT
                 >::value_type
-            >::type,
-            typename std::iterator_traits<IteratorT>::difference_type
-        > {
-        public:
-            using inner_type = typename std::iterator_traits<IteratorT>::value_type;
-
-            using value_type = decltype (std::get<I> (std::declval<inner_type> ()));
+            >::type;
+            using difference_type = typename std::iterator_traits<IteratorT>::difference_type;
             using reference  = value_type&;
             using const_reference  = value_type const&;