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// { dg-do compile { target c++11 } }
// Copyright (C) 2011-2019 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
#include <functional>
#include <type_traits>
struct S { };
struct S0
{
typedef int argument_type;
};
struct S1
{
typedef float first_argument_type;
};
struct S2
{
typedef char second_argument_type;
};
struct S01 : S0, S1 { };
struct S02 : S0, S2 { };
struct S12 : S1, S2 { };
struct S012 : S0, S1, S2 { };
using std::true_type;
using std::false_type;
using std::__void_t;
_GLIBCXX_HAS_NESTED_TYPE(argument_type)
_GLIBCXX_HAS_NESTED_TYPE(first_argument_type)
_GLIBCXX_HAS_NESTED_TYPE(second_argument_type)
template<typename T>
struct has_arg_type : __has_argument_type<T>
{ };
template<typename T>
struct has_1st_arg_type : __has_first_argument_type<T>
{ };
template<typename T>
struct has_2nd_arg_type : __has_second_argument_type<T>
{ };
template<typename T, bool = has_arg_type<T>::value>
struct test_arg_type
{
static_assert( !has_arg_type<std::reference_wrapper<T>>::value,
"reference_wrapper has no nested argument_type");
};
template<typename T>
struct test_arg_type<T, true>
{
typedef std::reference_wrapper<T> ref;
static_assert( has_arg_type<ref>::value,
"reference_wrapper has nested argument_type");
static_assert(
std::is_same< typename T::argument_type,
typename ref::argument_type >::value,
"reference_wrapper has the correct argument_type");
};
template<typename T,
bool = has_1st_arg_type<T>::value && has_2nd_arg_type<T>::value>
struct test_1st_2nd_arg_types
{
typedef std::reference_wrapper<T> ref;
static_assert( !has_1st_arg_type<ref>::value,
"reference_wrapper has no nested first_argument_type");
static_assert( !has_2nd_arg_type<ref>::value,
"reference_wrapper has no nested second_argument_type");
};
template<typename T>
struct test_1st_2nd_arg_types<T, true>
{
typedef std::reference_wrapper<T> ref;
static_assert( has_1st_arg_type<ref>::value,
"reference_wrapper has nested first_argument_type");
static_assert( has_2nd_arg_type<ref>::value,
"reference_wrapper has nested second_argument_type");
static_assert(
std::is_same< typename T::first_argument_type,
typename ref::first_argument_type>::value,
"reference_wrapper has correct first_argument_type");
static_assert(
std::is_same< typename T::second_argument_type,
typename ref::second_argument_type>::value,
"reference_wrapper has correct second_argument_type");
};
template<typename T>
void test()
{
test_arg_type<T> t __attribute__((unused));
test_arg_type<const T> tc __attribute__((unused));
test_arg_type<volatile T> tv __attribute__((unused));
test_arg_type<const volatile T> tcv __attribute__((unused));
test_1st_2nd_arg_types<T> t12 __attribute__((unused));
test_1st_2nd_arg_types<const T> t12c __attribute__((unused));
test_1st_2nd_arg_types<volatile T> t12v __attribute__((unused));
test_1st_2nd_arg_types<const volatile T> t12cv __attribute__((unused));
}
int main()
{
test<S>();
test<S0>();
test<S1>();
test<S2>();
test<S01>();
test<S02>();
test<S12>();
test<S012>();
}
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