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// Copyright Louis Dionne 2013-2016
// 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/detail/ebo.hpp>
#include <boost/hana/assert.hpp>
#include <string>
#include <type_traits>
#include <utility>
namespace hana = boost::hana;
using hana::detail::ebo;
template <int> struct empty { };
template <int> struct idx;
#ifdef BOOST_HANA_WORKAROUND_MSVC_EMPTYBASE
template <typename ...Bases> struct __declspec(empty_bases) inherit : Bases... { };
#else
template <typename ...Bases> struct inherit : Bases... { };
#endif
static_assert(sizeof(inherit<>) == sizeof(inherit<ebo<idx<0>, empty<0>>>), "");
static_assert(sizeof(inherit<>) == sizeof(inherit<ebo<idx<0>, empty<0>>, ebo<idx<1>, empty<1>>>), "");
static_assert(sizeof(inherit<>) == sizeof(inherit<ebo<idx<0>, empty<0>>, ebo<idx<1>, empty<1>>, ebo<idx<2>, empty<2>>>), "");
int main() {
// Test default-construction
{
constexpr ebo<idx<0>, int> e;
static_assert(hana::detail::ebo_get<idx<0>>(e) == 0, "");
}
// Test construction of a non-empty object
{
ebo<idx<0>, std::string> e{"foobar"};
BOOST_HANA_RUNTIME_CHECK(hana::detail::ebo_get<idx<0>>(e) == "foobar");
}
{
ebo<idx<0>, std::string> e{};
BOOST_HANA_RUNTIME_CHECK(hana::detail::ebo_get<idx<0>>(e) == "");
}
// Test construction of a non default-constructible type
{
struct nodefault {
nodefault() = delete;
explicit nodefault(char const*) { }
};
ebo<idx<0>, nodefault> e{"foobar"};
}
// Get lvalue, const lvalue and rvalue with a non-empty type
{
ebo<idx<0>, std::string> e{"foobar"};
std::string& s = hana::detail::ebo_get<idx<0>>(e);
BOOST_HANA_RUNTIME_CHECK(s == "foobar");
s = "foobaz";
BOOST_HANA_RUNTIME_CHECK(hana::detail::ebo_get<idx<0>>(e) == "foobaz");
}
{
ebo<idx<0>, std::string> const e{"foobar"};
std::string const& s = hana::detail::ebo_get<idx<0>>(e);
BOOST_HANA_RUNTIME_CHECK(s == "foobar");
}
{
ebo<idx<0>, std::string> e{"foobar"};
std::string&& s = hana::detail::ebo_get<idx<0>>(std::move(e));
BOOST_HANA_RUNTIME_CHECK(s == "foobar");
}
// Get lvalue, const lvalue and rvalue with an empty type
{
ebo<idx<0>, empty<0>> e{};
empty<0>& s = hana::detail::ebo_get<idx<0>>(e);
(void)s;
}
{
ebo<idx<0>, empty<0>> const e{};
empty<0> const& s = hana::detail::ebo_get<idx<0>>(e);
(void)s;
}
{
ebo<idx<0>, empty<0>> e{};
empty<0>&& s = hana::detail::ebo_get<idx<0>>(std::move(e));
(void)s;
}
}
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