Extract Header qforeach.h from qglobal.h

Task-number: QTBUG-99313
Change-Id: Ie89314ca7022e88c1fea957880c5aa4a41640744
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

3 files changed, 140 insertions, 84 deletions

diff --git a/src/corelib/global/qforeach.h b/src/corelib/global/qforeach.h
new file mode 100644
index 0000000000..2b6b9f7cee
--- /dev/null
+++ b/src/corelib/global/qforeach.h
@@ -0,0 +1,135 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Copyright (C) 2019 Intel Corporation.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QFOREACH_H
+#define QFOREACH_H
+
+#include <QtCore/qglobal.h>
+
+QT_BEGIN_NAMESPACE
+
+#if 0
+#pragma qt_class(QForeach)
+#pragma qt_sync_stop_processing
+#endif
+
+#ifndef QT_NO_FOREACH
+
+namespace QtPrivate {
+
+template <typename T>
+class QForeachContainer {
+    Q_DISABLE_COPY(QForeachContainer)
+public:
+    QForeachContainer(const T &t) : c(t), i(qAsConst(c).begin()), e(qAsConst(c).end()) {}
+    QForeachContainer(T &&t) : c(std::move(t)), i(qAsConst(c).begin()), e(qAsConst(c).end())  {}
+
+    QForeachContainer(QForeachContainer &&other)
+        : c(std::move(other.c)),
+          i(qAsConst(c).begin()),
+          e(qAsConst(c).end()),
+          control(std::move(other.control))
+    {
+    }
+
+    QForeachContainer &operator=(QForeachContainer &&other)
+    {
+        c = std::move(other.c);
+        i = qAsConst(c).begin();
+        e = qAsConst(c).end();
+        control = std::move(other.control);
+        return *this;
+    }
+
+    T c;
+    typename T::const_iterator i, e;
+    int control = 1;
+};
+
+// Containers that have a detach function are considered shared, and are OK in a foreach loop
+template <typename T, typename = decltype(std::declval<T>().detach())>
+inline void warnIfContainerIsNotShared(int) {}
+
+#if QT_DEPRECATED_SINCE(6, 0)
+// Other containers will copy themselves if used in foreach, this use is deprecated
+template <typename T>
+QT_DEPRECATED_VERSION_X_6_0("Do not use foreach/Q_FOREACH with containers which are not implicitly shared. "
+    "Prefer using a range-based for loop with these containers: `for (const auto &it : container)`, "
+    "keeping in mind that range-based for doesn't copy the container as Q_FOREACH does")
+inline void warnIfContainerIsNotShared(...) {}
+#endif
+
+template<typename T>
+QForeachContainer<typename std::decay<T>::type> qMakeForeachContainer(T &&t)
+{
+    warnIfContainerIsNotShared<typename std::decay<T>::type>(0);
+    return QForeachContainer<typename std::decay<T>::type>(std::forward<T>(t));
+}
+
+}
+
+// Use C++17 if statement with initializer. User's code ends up in a else so
+// scoping of different ifs is not broken
+#define Q_FOREACH_IMPL(variable, name, container)                                             \
+    for (auto name = QtPrivate::qMakeForeachContainer(container); name.i != name.e; ++name.i) \
+        if (variable = *name.i; false) {} else
+
+#define Q_FOREACH_JOIN(A, B) Q_FOREACH_JOIN_IMPL(A, B)
+#define Q_FOREACH_JOIN_IMPL(A, B) A ## B
+
+#define Q_FOREACH(variable, container) \
+    Q_FOREACH_IMPL(variable, Q_FOREACH_JOIN(_container_, __LINE__), container)
+#endif // QT_NO_FOREACH
+
+#define Q_FOREVER for(;;)
+#ifndef QT_NO_KEYWORDS
+# ifndef QT_NO_FOREACH
+#  ifndef foreach
+#    define foreach Q_FOREACH
+#  endif
+# endif // QT_NO_FOREACH
+#  ifndef forever
+#    define forever Q_FOREVER
+#  endif
+#endif
+
+QT_END_NAMESPACE
+
+#endif /* QFOREACH_H */
diff --git a/src/corelib/global/qglobal.cpp b/src/corelib/global/qglobal.cpp
index befc007868..a9c44d3237 100644
--- a/src/corelib/global/qglobal.cpp
+++ b/src/corelib/global/qglobal.cpp
@@ -3701,7 +3701,7 @@ bool qunsetenv(const char *varName)
 
 /*!
     \macro forever
-    \relates <QtGlobal>
+    \relates <QForeach>
 
     This macro is provided for convenience for writing infinite
     loops.
@@ -3722,7 +3722,7 @@ bool qunsetenv(const char *varName)
 
 /*!
     \macro Q_FOREVER
-    \relates <QtGlobal>
+    \relates <QForeach>
 
     Same as \l{forever}.
 
@@ -3734,7 +3734,7 @@ bool qunsetenv(const char *varName)
 
 /*!
     \macro foreach(variable, container)
-    \relates <QtGlobal>
+    \relates <QForeach>
 
     This macro is used to implement Qt's \c foreach loop. The \a
     variable parameter is a variable name or variable definition; the
@@ -3756,7 +3756,7 @@ bool qunsetenv(const char *varName)
 
 /*!
     \macro Q_FOREACH(variable, container)
-    \relates <QtGlobal>
+    \relates <QForeach>
 
     Same as foreach(\a variable, \a container).
 
diff --git a/src/corelib/global/qglobal.h b/src/corelib/global/qglobal.h
index e44929b379..d686bbdb8a 100644
--- a/src/corelib/global/qglobal.h
+++ b/src/corelib/global/qglobal.h
@@ -1242,86 +1242,6 @@ constexpr std::underlying_type_t<Enum> qToUnderlying(Enum e) noexcept
 #define Q_IMPLICIT
 #endif
 
-#ifndef QT_NO_FOREACH
-
-namespace QtPrivate {
-
-template <typename T>
-class QForeachContainer {
-    Q_DISABLE_COPY(QForeachContainer)
-public:
-    QForeachContainer(const T &t) : c(t), i(qAsConst(c).begin()), e(qAsConst(c).end()) {}
-    QForeachContainer(T &&t) : c(std::move(t)), i(qAsConst(c).begin()), e(qAsConst(c).end())  {}
-
-    QForeachContainer(QForeachContainer &&other)
-        : c(std::move(other.c)),
-          i(qAsConst(c).begin()),
-          e(qAsConst(c).end()),
-          control(std::move(other.control))
-    {
-    }
-
-    QForeachContainer &operator=(QForeachContainer &&other)
-    {
-        c = std::move(other.c);
-        i = qAsConst(c).begin();
-        e = qAsConst(c).end();
-        control = std::move(other.control);
-        return *this;
-    }
-
-    T c;
-    typename T::const_iterator i, e;
-    int control = 1;
-};
-
-// Containers that have a detach function are considered shared, and are OK in a foreach loop
-template <typename T, typename = decltype(std::declval<T>().detach())>
-inline void warnIfContainerIsNotShared(int) {}
-
-#if QT_DEPRECATED_SINCE(6, 0)
-// Other containers will copy themselves if used in foreach, this use is deprecated
-template <typename T>
-QT_DEPRECATED_VERSION_X_6_0("Do not use foreach/Q_FOREACH with containers which are not implicitly shared. "
-    "Prefer using a range-based for loop with these containers: `for (const auto &it : container)`, "
-    "keeping in mind that range-based for doesn't copy the container as Q_FOREACH does")
-inline void warnIfContainerIsNotShared(...) {}
-#endif
-
-template<typename T>
-QForeachContainer<typename std::decay<T>::type> qMakeForeachContainer(T &&t)
-{
-    warnIfContainerIsNotShared<typename std::decay<T>::type>(0);
-    return QForeachContainer<typename std::decay<T>::type>(std::forward<T>(t));
-}
-
-}
-
-// Use C++17 if statement with initializer. User's code ends up in a else so
-// scoping of different ifs is not broken
-#define Q_FOREACH_IMPL(variable, name, container)                                             \
-    for (auto name = QtPrivate::qMakeForeachContainer(container); name.i != name.e; ++name.i) \
-        if (variable = *name.i; false) {} else
-
-#define Q_FOREACH_JOIN(A, B) Q_FOREACH_JOIN_IMPL(A, B)
-#define Q_FOREACH_JOIN_IMPL(A, B) A ## B
-
-#define Q_FOREACH(variable, container) \
-    Q_FOREACH_IMPL(variable, Q_FOREACH_JOIN(_container_, __LINE__), container)
-#endif // QT_NO_FOREACH
-
-#define Q_FOREVER for(;;)
-#ifndef QT_NO_KEYWORDS
-# ifndef QT_NO_FOREACH
-#  ifndef foreach
-#    define foreach Q_FOREACH
-#  endif
-# endif // QT_NO_FOREACH
-#  ifndef forever
-#    define forever Q_FOREVER
-#  endif
-#endif
-
 template <typename T> inline T *qGetPtrHelper(T *ptr) noexcept { return ptr; }
 template <typename Ptr> inline auto qGetPtrHelper(Ptr &ptr) noexcept -> decltype(ptr.get())
 { static_assert(noexcept(ptr.get()), "Smart d pointers for Q_DECLARE_PRIVATE must have noexcept get()"); return ptr.get(); }
@@ -1485,6 +1405,7 @@ QT_END_NAMESPACE
 #include <QtCore/qglobalstatic.h>
 #include <QtCore/qnumeric.h>
 #include <QtCore/qversiontagging.h>
+#include <QtCore/qforeach.h>
 
 #endif /* __cplusplus */
 #endif /* !__ASSEMBLER__ */