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Diffstat (limited to 'src/corelib/global/qcompare_impl.h')
| -rw-r--r-- | src/corelib/global/qcompare_impl.h | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/src/corelib/global/qcompare_impl.h b/src/corelib/global/qcompare_impl.h new file mode 100644 index 0000000000..c52417fcec --- /dev/null +++ b/src/corelib/global/qcompare_impl.h @@ -0,0 +1,34 @@ +// Copyright (C) 2020 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Giuseppe D'Angelo <giuseppe.dangelo@kdab.com> +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only + +#ifndef QCOMPARE_IMPL_H +#define QCOMPARE_IMPL_H + +#if 0 +#pragma qt_sync_skip_header_check +#pragma qt_sync_stop_processing +#endif + +#include <QtCore/qtconfigmacros.h> +#include <QtCore/qcompilerdetection.h> + +QT_BEGIN_NAMESPACE + +namespace QtPrivate { + +// [cmp.categories.pre] / 3, but using a safe bool trick +// and also rejecting std::nullptr_t (unlike the example) +class CompareAgainstLiteralZero { +public: + using SafeZero = void (CompareAgainstLiteralZero::*)(); + Q_IMPLICIT constexpr CompareAgainstLiteralZero(SafeZero) noexcept {} + + template <typename T, std::enable_if_t<std::is_null_pointer_v<T>, bool> = true> + CompareAgainstLiteralZero(T) = delete; +}; + +} // namespace QtPrivate + +QT_END_NAMESPACE + +#endif // QCOMPARE_IMPL_H |