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Diffstat (limited to 'src/boost/libs/hana/example/optional/sfinae.cpp')
-rw-r--r-- | src/boost/libs/hana/example/optional/sfinae.cpp | 21 |
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); +} |