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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// type_traits
// is_empty
// T is a non-union class type with:
// no non-static data members,
// no unnamed bit-fields of non-zero length,
// no virtual member functions,
// no virtual base classes,
// and no base class B for which is_empty_v<B> is false.
#include <type_traits>
#include "test_macros.h"
template <class T>
void test_is_empty()
{
static_assert( std::is_empty<T>::value, "");
static_assert( std::is_empty<const T>::value, "");
static_assert( std::is_empty<volatile T>::value, "");
static_assert( std::is_empty<const volatile T>::value, "");
#if TEST_STD_VER > 14
static_assert( std::is_empty_v<T>, "");
static_assert( std::is_empty_v<const T>, "");
static_assert( std::is_empty_v<volatile T>, "");
static_assert( std::is_empty_v<const volatile T>, "");
#endif
}
template <class T>
void test_is_not_empty()
{
static_assert(!std::is_empty<T>::value, "");
static_assert(!std::is_empty<const T>::value, "");
static_assert(!std::is_empty<volatile T>::value, "");
static_assert(!std::is_empty<const volatile T>::value, "");
#if TEST_STD_VER > 14
static_assert(!std::is_empty_v<T>, "");
static_assert(!std::is_empty_v<const T>, "");
static_assert(!std::is_empty_v<volatile T>, "");
static_assert(!std::is_empty_v<const volatile T>, "");
#endif
}
class Empty {};
struct NotEmpty { int foo; };
class VirtualFn
{
virtual ~VirtualFn();
};
union Union {};
struct EmptyBase : public Empty {};
struct VirtualBase : virtual Empty {};
struct NotEmptyBase : public NotEmpty {};
struct StaticMember { static int foo; };
struct NonStaticMember { int foo; };
struct bit_zero
{
int : 0;
};
struct bit_one
{
int : 1;
};
int main(int, char**)
{
test_is_not_empty<void>();
test_is_not_empty<int&>();
test_is_not_empty<int>();
test_is_not_empty<double>();
test_is_not_empty<int*>();
test_is_not_empty<const int*>();
test_is_not_empty<char[3]>();
test_is_not_empty<char[]>();
test_is_not_empty<Union>();
test_is_not_empty<NotEmpty>();
test_is_not_empty<VirtualFn>();
test_is_not_empty<VirtualBase>();
test_is_not_empty<NotEmptyBase>();
test_is_not_empty<NonStaticMember>();
// test_is_not_empty<bit_one>();
test_is_empty<Empty>();
test_is_empty<EmptyBase>();
test_is_empty<StaticMember>();
test_is_empty<bit_zero>();
return 0;
}
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