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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/tuple.hpp>
#include <string>
namespace hana = boost::hana;
struct Empty {};
struct S {
constexpr S()
: a{1, Empty{}},
k(hana::at_c<0>(a)),
e(hana::at_c<1>(a))
{ }
hana::tuple<int, Empty> a;
int k;
Empty e;
};
constexpr hana::tuple<int, int> getP () { return { 3, 4 }; }
int main() {
{
using T = hana::tuple<int>;
T t(3);
BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 3);
hana::at_c<0>(t) = 2;
BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 2);
}
{
using T = hana::tuple<std::string, int>;
T t("high", 5);
BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == "high");
BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == 5);
hana::at_c<0>(t) = "four";
hana::at_c<1>(t) = 4;
BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == "four");
BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == 4);
}
{
using T = hana::tuple<double&, std::string, int>;
double d = 1.5;
T t(d, "high", 5);
BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 1.5);
BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == "high");
BOOST_HANA_RUNTIME_CHECK(hana::at_c<2>(t) == 5);
hana::at_c<0>(t) = 2.5;
hana::at_c<1>(t) = "four";
hana::at_c<2>(t) = 4;
BOOST_HANA_RUNTIME_CHECK(hana::at_c<0>(t) == 2.5);
BOOST_HANA_RUNTIME_CHECK(hana::at_c<1>(t) == "four");
BOOST_HANA_RUNTIME_CHECK(hana::at_c<2>(t) == 4);
BOOST_HANA_RUNTIME_CHECK(d == 2.5);
}
// get on a rvalue tuple
{
static_assert(hana::at_c<0>(hana::tuple<float, int, double, long>{0.0f, 1, 2.0, 3L}) == 0, "" );
static_assert(hana::at_c<1>(hana::tuple<float, int, double, long>{0.0f, 1, 2.0, 3L}) == 1, "" );
static_assert(hana::at_c<2>(hana::tuple<float, int, double, long>{0.0f, 1, 2.0, 3L}) == 2, "" );
static_assert(hana::at_c<3>(hana::tuple<float, int, double, long>{0.0f, 1, 2.0, 3L}) == 3, "" );
static_assert(S().k == 1, "");
static_assert(hana::at_c<1>(getP()) == 4, "");
}
{
// make sure get<> returns the right types
struct T { };
struct U { };
struct V { };
hana::tuple<T, U, V> xs{};
(void)static_cast<T>(hana::at_c<0>(xs));
(void)static_cast<U>(hana::at_c<1>(xs));
(void)static_cast<V>(hana::at_c<2>(xs));
}
}
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