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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/integral_constant.hpp>
#include <boost/hana/less.hpp>
#include <boost/hana/plus.hpp>
#include <boost/hana/while.hpp>
#include <vector>
namespace hana = boost::hana;
using namespace hana::literals;
int main() {
// while_ with a Constant condition (loop is unrolled at compile-time)
{
std::vector<int> ints;
auto final_state = hana::while_(hana::less.than(10_c), 0_c, [&](auto i) {
ints.push_back(i);
return i + 1_c;
});
// The state is known at compile-time
BOOST_HANA_CONSTANT_CHECK(final_state == 10_c);
BOOST_HANA_RUNTIME_CHECK(ints == std::vector<int>{0, 1, 2, 3, 4, 5, 6, 7, 8, 9});
}
// while_ with a constexpr or runtime condition (loop is not unrolled)
{
std::vector<int> ints;
int final_state = hana::while_(hana::less.than(10), 0, [&](int i) {
ints.push_back(i);
return i + 1;
});
// The state is known only at runtime, or at compile-time if constexpr
BOOST_HANA_RUNTIME_CHECK(final_state == 10);
BOOST_HANA_RUNTIME_CHECK(ints == std::vector<int>{0, 1, 2, 3, 4, 5, 6, 7, 8, 9});
}
}
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