Extract header qtypetraits.h from qglobal.h

Task-number: QTBUG-99313
Change-Id: I6cb76607213ca5d64dec669a39e8a59e13b21497
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/CMakeLists.txt

@@ -85,6 +85,7 @@ qt_internal_add_module(Core
         global/qtversionchecks.h
         global/qtypeinfo.h
         global/qtypes.cpp global/qtypes.h
+        global/qtypetraits.h
         global/qvolatile_p.h
         global/q20algorithm.h
         global/q20functional.h

src/corelib/global/qglobal.cpp

@@ -2797,15 +2797,6 @@ void qAbort()
     that qExchange() returns a non-const object, so Qt containers may detach.
 */
 
-/*!
-    \fn template <typename Enum> std::underlying_type_t<Enum> qToUnderlying(Enum e)
-    \relates <QtGlobal>
-    \since 6.2
-
-    Converts the enumerator \a e to the equivalent value expressed in its
-    enumeration's underlying type.
-*/
-
 /*!
     \macro Q_LIKELY(expr)
     \relates <QtGlobal>

src/corelib/global/qglobal.h

@@ -158,13 +158,6 @@ noexcept(std::conjunction_v<std::is_nothrow_move_constructible<T>, std::is_nothr
     return old;
 }
 
-// like std::to_underlying
-template <typename Enum>
-constexpr std::underlying_type_t<Enum> qToUnderlying(Enum e) noexcept
-{
-    return static_cast<std::underlying_type_t<Enum>>(e);
-}
-
 QT_END_NAMESPACE
 
 // We need to keep QTypeInfo, QSysInfo, QFlags, qDebug & family in qglobal.h for compatibility with Qt 4.
@@ -188,6 +181,7 @@ QT_END_NAMESPACE
 #include <QtCore/qtdeprecationmarkers.h>
 #include <QtCore/qtranslation.h>
 #include <QtCore/qtresource.h>
+#include <QtCore/qtypetraits.h>
 #include <QtCore/qversiontagging.h>
 
 #endif /* __cplusplus */

src/corelib/global/qtypetraits.h

@@ -0,0 +1,27 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QTYPETRAITS_H
+#define QTYPETRAITS_H
+
+#include <QtCore/qtconfigmacros.h>
+
+#include <type_traits>
+
+#if 0
+#pragma qt_class(QTypeTraits)
+#pragma qt_sync_stop_processing
+#endif
+
+QT_BEGIN_NAMESPACE
+
+// like std::to_underlying
+template <typename Enum>
+constexpr std::underlying_type_t<Enum> qToUnderlying(Enum e) noexcept
+{
+    return static_cast<std::underlying_type_t<Enum>>(e);
+}
+
+QT_END_NAMESPACE
+
+#endif // QTYPETRAITS_H

src/corelib/global/qtypetraits.qdoc

@@ -0,0 +1,11 @@
+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
+
+/*!
+    \fn template <typename Enum> std::underlying_type_t<Enum> qToUnderlying(Enum e)
+    \relates <QTypeTraits>
+    \since 6.2
+
+    Converts the enumerator \a e to the equivalent value expressed in its
+    enumeration's underlying type.
+*/