1// Copyright (C) 2020 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#ifndef QCOMPARE_IMPL_H
5#define QCOMPARE_IMPL_H
6
7#if 0
8#pragma qt_sync_skip_header_check
9#pragma qt_sync_stop_processing
10#endif
11
12#include <QtCore/qtconfigmacros.h>
13#include <QtCore/qcompilerdetection.h>
14
15QT_BEGIN_NAMESPACE
16
17namespace QtPrivate {
18
19// [cmp.categories.pre] / 3, but using a safe bool trick
20// and also rejecting std::nullptr_t (unlike the example)
21class CompareAgainstLiteralZero {
22public:
23 using SafeZero = void (CompareAgainstLiteralZero::*)();
24 Q_IMPLICIT constexpr CompareAgainstLiteralZero(SafeZero) noexcept {}
25
26 template <typename T, std::enable_if_t<std::is_null_pointer_v<T>, bool> = true>
27 CompareAgainstLiteralZero(T) = delete;
28};
29
30} // namespace QtPrivate
31
32QT_END_NAMESPACE
33
34#endif // QCOMPARE_IMPL_H
35

source code of qtbase/src/corelib/global/qcompare_impl.h