Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 21 insertions, 0 deletions

diff --git a/src/boost/libs/hana/example/optional/sfinae.cpp b/src/boost/libs/hana/example/optional/sfinae.cpp
new file mode 100644
index 000000000..1fe9adf0e
--- /dev/null
+++ b/src/boost/libs/hana/example/optional/sfinae.cpp
@@ -0,0 +1,21 @@
+// 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/assert.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/equal.hpp>
+#include <boost/hana/optional.hpp>
+namespace hana = boost::hana;
+
+
+int main() {
+    BOOST_HANA_CONSTEXPR_LAMBDA auto incr = [](auto x) -> decltype(x + 1) {
+        return x + 1;
+    };
+
+    BOOST_HANA_CONSTEXPR_CHECK(hana::sfinae(incr)(1) == hana::just(2));
+
+    struct invalid { };
+    BOOST_HANA_CONSTANT_CHECK(hana::sfinae(incr)(invalid{}) == hana::nothing);
+}