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Diffstat (limited to 'src/boost/libs/hana/example/tap.cpp')
-rw-r--r-- | src/boost/libs/hana/example/tap.cpp | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/src/boost/libs/hana/example/tap.cpp b/src/boost/libs/hana/example/tap.cpp new file mode 100644 index 000000000..6c93eeb55 --- /dev/null +++ b/src/boost/libs/hana/example/tap.cpp @@ -0,0 +1,28 @@ +// 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/chain.hpp> +#include <boost/hana/equal.hpp> +#include <boost/hana/tap.hpp> +#include <boost/hana/tuple.hpp> + +#include <set> +namespace hana = boost::hana; + + +int main() { + // We use a sorted container because the order in which the functions + // are called is unspecified. + std::set<int> before, after; + + auto xs = hana::make_tuple(1, 2, 3) + | hana::tap<hana::tuple_tag>([&](int x) { before.insert(x); }) + | [](auto x) { return hana::make_tuple(x, -x); } + | hana::tap<hana::tuple_tag>([&](int x) { after.insert(x); }); + + BOOST_HANA_RUNTIME_CHECK(before == std::set<int>{1, 2, 3}); + BOOST_HANA_RUNTIME_CHECK(after == std::set<int>{1, -1, 2, -2, 3, -3}); + BOOST_HANA_RUNTIME_CHECK(xs == hana::make_tuple(1, -1, 2, -2, 3, -3)); +} |