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-rw-r--r--src/boost/libs/hana/example/unfold_right.cpp28
1 files changed, 28 insertions, 0 deletions
diff --git a/src/boost/libs/hana/example/unfold_right.cpp b/src/boost/libs/hana/example/unfold_right.cpp
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+++ b/src/boost/libs/hana/example/unfold_right.cpp
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+// 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/equal.hpp>
+#include <boost/hana/if.hpp>
+#include <boost/hana/integral_constant.hpp>
+#include <boost/hana/minus.hpp>
+#include <boost/hana/optional.hpp>
+#include <boost/hana/pair.hpp>
+#include <boost/hana/tuple.hpp>
+#include <boost/hana/unfold_right.hpp>
+namespace hana = boost::hana;
+
+
+BOOST_HANA_CONSTANT_CHECK(
+ hana::unfold_right<hana::tuple_tag>(hana::int_c<10>, [](auto x) {
+ return hana::if_(x == hana::int_c<0>,
+ hana::nothing,
+ hana::just(hana::make_pair(x, x - hana::int_c<1>))
+ );
+ })
+ ==
+ hana::tuple_c<int, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1>
+);
+
+int main() { }