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Diffstat (limited to 'src/boost/libs/hana/example/index_if.cpp')
-rw-r--r-- | src/boost/libs/hana/example/index_if.cpp | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/boost/libs/hana/example/index_if.cpp b/src/boost/libs/hana/example/index_if.cpp new file mode 100644 index 000000000..098b2b8c2 --- /dev/null +++ b/src/boost/libs/hana/example/index_if.cpp @@ -0,0 +1,22 @@ +// 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) + +#include <boost/hana/core/is_a.hpp> +#include <boost/hana/equal.hpp> +#include <boost/hana/index_if.hpp> +#include <boost/hana/integral_constant.hpp> +#include <boost/hana/optional.hpp> +#include <boost/hana/tuple.hpp> +namespace hana = boost::hana; + + +constexpr auto xs = hana::make_tuple(0, '1', 2.0); + +static_assert(hana::index_if(xs, hana::is_an<int>) == hana::just(hana::size_c<0>), ""); +static_assert(hana::index_if(xs, hana::is_a<char>) == hana::just(hana::size_c<1>), ""); +static_assert(hana::index_if(xs, hana::is_a<double>) == hana::just(hana::size_c<2>), ""); +static_assert(hana::index_if(xs, hana::is_a<hana::tuple_tag>) == hana::nothing, ""); + +int main() { } |