diff --git a/include/boost/hana/detail/dependent_on.hpp b/include/boost/hana/detail/dependent_on.hpp
index 9ea56da2c..22d72e936 100644
--- a/include/boost/hana/detail/dependent_on.hpp
+++ b/include/boost/hana/detail/dependent_on.hpp
@@ -11,11 +11,11 @@ Distributed under the Boost Software License, Version 1.0.
 #define BOOST_HANA_DETAIL_DEPENDENT_ON_HPP
 
 namespace boost { namespace hana { namespace detail {
-    template <typename, typename T>
-    struct dependent_on_impl { using type = T; };
+    template <bool dummy, typename T>
+    struct dependent_on { using type = T; };
 
-    template <typename Dummy, typename T>
-    using dependent_on = typename dependent_on_impl<Dummy, T>::type;
+    template <bool dummy, typename T>
+    using dependent_on_t = typename dependent_on<dummy, T>::type;
 }}} // end namespace boost::hana::detail
 
 #endif // !BOOST_HANA_DETAIL_DEPENDENT_ON_HPP
diff --git a/include/boost/hana/maybe.hpp b/include/boost/hana/maybe.hpp
index c3a2d47bb..e2c0a256e 100644
--- a/include/boost/hana/maybe.hpp
+++ b/include/boost/hana/maybe.hpp
@@ -103,7 +103,7 @@ namespace boost { namespace hana {
     //! @snippet example/maybe/foldable.cpp main
     template <typename ...Nothing>
     struct Foldable::instance<Maybe, Nothing...>
-        : detail::dependent_on<char[sizeof...(Nothing) + 1], Foldable::mcd>
+        : detail::dependent_on_t<(bool)sizeof...(Nothing), Foldable::mcd>
     {
         template <typename F, typename S, typename M>
         static constexpr auto foldr_impl(F f, S s, M m)
diff --git a/include/boost/hana/type.hpp b/include/boost/hana/type.hpp
index 0ab878f5f..7f0919f0c 100644
--- a/include/boost/hana/type.hpp
+++ b/include/boost/hana/type.hpp
@@ -136,19 +136,19 @@ namespace boost { namespace hana {
 
         template <typename f>
         struct metafunction_class {
-            // We need to delay the fetching of `f::apply` in case `f` is
-            // invalid because we want to stay SFINAE friendly.
+            // We use `dependent_on` to delay the fetching of `f::apply` in
+            // case `f` is invalid because we want to stay SFINAE friendly.
             template <typename ...xs>
             using apply = typename detail::dependent_on<
-                char[static_cast<bool>(sizeof...(xs)) + 1], f
-            >::template apply<xs...>;
+                (bool)sizeof...(xs), f
+            >::type::template apply<xs...>;
 
             template <typename ...xs>
             constexpr auto operator()(xs...) const -> decltype(
                 type<
                     typename detail::dependent_on<
-                        char[static_cast<bool>(sizeof...(xs)) + 1], f
-                    >::template apply<typename xs::type...>::type
+                        (bool)sizeof...(xs), f
+                    >::type::template apply<typename xs::type...>::type
                 >
             ) { return {}; }
         };