1 files changed, 41 insertions, 0 deletions
diff --git a/src/boost/libs/hana/test/functional/fix.cpp b/src/boost/libs/hana/test/functional/fix.cpp
new file mode 100644
index 00000000..79041b4a
--- /dev/null
+++ b/src/boost/libs/hana/test/functional/fix.cpp
@@ -0,0 +1,41 @@
+// Copyright Louis Dionne 2013-2017
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+
+#include <boost/hana/functional/fix.hpp>
+
+#include <boost/hana/assert.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/equal.hpp>
+#include <boost/hana/eval_if.hpp>
+#include <boost/hana/functional/always.hpp>
+#include <boost/hana/integral_constant.hpp>
+#include <boost/hana/minus.hpp>
+#include <boost/hana/mult.hpp>
+namespace hana = boost::hana;
+
+
+BOOST_HANA_CONSTEXPR_LAMBDA auto fact = hana::fix([](auto fact, auto n) {
+    return hana::eval_if(hana::equal(n, hana::ullong_c<0>),
+        hana::always(hana::ullong_c<1>),
+        [=](auto _) { return hana::mult(n, fact(_(n) - hana::ullong_c<1>)); }
+    );
+});
+
+constexpr unsigned long long reference(unsigned long long n)
+{ return n == 0 ? 1 : n * reference(n - 1); }
+
+template <int n>
+void test() {
+    BOOST_HANA_CONSTANT_CHECK(hana::equal(
+        fact(hana::ullong_c<n>),
+        hana::ullong_c<reference(n)>
+    ));
+    test<n - 1>();
+}
+
+template <> void test<-1>() { }
+
+int main() {
+    test<15>();
+}