1 files changed, 56 insertions, 0 deletions
diff --git a/src/boost/libs/hana/test/_include/support/counter.hpp b/src/boost/libs/hana/test/_include/support/counter.hpp
new file mode 100644
index 000000000..4640363d7
--- /dev/null
+++ b/src/boost/libs/hana/test/_include/support/counter.hpp
@@ -0,0 +1,56 @@
+// Copyright Louis Dionne 2013-2017
+// Copyright Jason Rice 2017
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+
+#ifndef TEST_SUPPORT_COUNTER_HPP
+#define TEST_SUPPORT_COUNTER_HPP
+
+#include <boost/hana/fwd/at.hpp>
+#include <boost/hana/fwd/concept/iterable.hpp>
+#include <boost/hana/fwd/drop_front.hpp>
+#include <boost/hana/fwd/is_empty.hpp>
+#include <boost/hana/integral_constant.hpp>
+
+
+// Counter - an infinite iterable for the masses
+
+struct Counter_tag { };
+
+template <std::size_t N = 0>
+struct Counter {
+    using hana_tag = Counter_tag;
+    static constexpr std::size_t value = N;
+};
+
+
+namespace boost { namespace hana {
+    //////////////////////////////////////////////////////////////////////////
+    // Iterable
+    //////////////////////////////////////////////////////////////////////////
+    template <>
+    struct at_impl<Counter_tag> {
+        template <typename T, typename N>
+        static constexpr decltype(auto) apply(T, N) {
+            return hana::size_c<T::value + N::value>;
+        }
+    };
+
+    template <>
+    struct drop_front_impl<Counter_tag> {
+        template <typename T, typename N>
+        static constexpr auto apply(T, N) {
+            return Counter<T::value + N::value>{};
+        }
+    };
+
+    template <>
+    struct is_empty_impl<Counter_tag> {
+        template <typename Xs>
+        static constexpr auto apply(Xs)
+            -> hana::false_
+        { return {}; }
+    };
+}} // end namespace boost::hana
+
+#endif // !TEST_SUPPORT_COUNTER_HPP