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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/fold_right.hpp>
#include <boost/hana/tuple.hpp>
#include <sstream>
#include <string>
namespace hana = boost::hana;
auto to_string = [](auto x) {
std::ostringstream ss;
ss << x;
return ss.str();
};
int main() {
auto f = [=](auto element, std::string s) {
return "f(" + to_string(element) + ", " + s + ")";
};
// with an initial state
BOOST_HANA_RUNTIME_CHECK(
hana::fold_right(hana::make_tuple(1, '2', 3.0, 4), "5", f)
==
"f(1, f(2, f(3, f(4, 5))))"
);
// without initial state
BOOST_HANA_RUNTIME_CHECK(
hana::fold_right(hana::make_tuple(1, '2', 3.0, 4, "5"), f)
==
"f(1, f(2, f(3, f(4, 5))))"
);
}
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