hana/test/_include/auto/for_each.hpp
2017-01-07 14:14:18 -08:00

65 lines
1.9 KiB
C++

// 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)
#ifndef BOOST_HANA_TEST_AUTO_FOR_EACH_HPP
#define BOOST_HANA_TEST_AUTO_FOR_EACH_HPP
#include <boost/hana/assert.hpp>
#include <boost/hana/for_each.hpp>
#include "test_case.hpp"
#include <laws/base.hpp>
#include <vector>
TestCase test_for_each{[]{
namespace hana = boost::hana;
using hana::test::ct_eq;
// Make sure the function is applied in left-to-right order.
{
auto check = [](auto ...xs) {
std::vector<int> seen{};
hana::for_each(MAKE_TUPLE(xs...), [&](int x) {
seen.push_back(x);
});
BOOST_HANA_RUNTIME_CHECK(seen == std::vector<int>{xs...});
};
check();
check(0);
check(0, 1);
check(0, 1, 2);
check(0, 1, 2, 3);
check(0, 1, 2, 3, 4);
}
// Make sure the function is never called when the sequence is empty.
{
struct undefined { };
hana::for_each(MAKE_TUPLE(), undefined{});
}
// Make sure it works with heterogeneous sequences.
{
hana::for_each(MAKE_TUPLE(ct_eq<0>{}), [](auto) { });
hana::for_each(MAKE_TUPLE(ct_eq<0>{}, ct_eq<1>{}), [](auto) { });
hana::for_each(MAKE_TUPLE(ct_eq<0>{}, ct_eq<1>{}, ct_eq<2>{}), [](auto) { });
hana::for_each(MAKE_TUPLE(ct_eq<0>{}, ct_eq<1>{}, ct_eq<2>{}, ct_eq<3>{}), [](auto) { });
}
// Make sure for_each is constexpr when used with a constexpr function
// and constexpr arguments. This used not to be the case.
#ifndef MAKE_TUPLE_NO_CONSTEXPR
{
struct f { constexpr void operator()(int) const { } };
constexpr int i = (hana::for_each(MAKE_TUPLE(1, 2, 3), f{}), 0);
(void)i;
}
#endif
}};
#endif // !BOOST_HANA_TEST_AUTO_FOR_EACH_HPP