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+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above copyright
+** notice, this list of conditions and the following disclaimer in
+** the documentation and/or other materials provided with the
+** distribution.
+** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
+** the names of its contributors may be used to endorse or promote
+** products derived from this software without specific prior written
+** permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+void myFunction(bool useSubClass)
+{
+ MyClass *p = useSubClass ? new MyClass() : new MySubClass;
+ QIODevice *device = handsOverOwnership();
+
+ if (m_value > 3) {
+ delete p;
+ delete device;
+ return;
+ }
+
+ try {
+ process(device);
+ }
+ catch (...) {
+ delete p;
+ delete device;
+ throw;
+ }
+
+ delete p;
+ delete device;
+}
+//! [0]
+
+//! [1]
+void myFunction(bool useSubClass)
+{
+ // assuming that MyClass has a virtual destructor
+ QScopedPointer<MyClass> p(useSubClass ? new MyClass() : new MySubClass);
+ QScopedPointer<QIODevice> device(handsOverOwnership());
+
+ if (m_value > 3)
+ return;
+
+ process(device);
+}
+//! [1]
+
+//! [2]
+ const QWidget *const p = new QWidget();
+ // is equivalent to:
+ const QScopedPointer<const QWidget> p(new QWidget());
+
+ QWidget *const p = new QWidget();
+ // is equivalent to:
+ const QScopedPointer<QWidget> p(new QWidget());
+
+ const QWidget *p = new QWidget();
+ // is equivalent to:
+ QScopedPointer<const QWidget> p(new QWidget());
+//! [2]
+
+//! [3]
+if (scopedPointer) {
+ ...
+}
+//! [3]
+
+//! [4]
+class MyPrivateClass; // forward declare MyPrivateClass
+
+class MyClass
+{
+private:
+ QScopedPointer<MyPrivateClass> privatePtr; // QScopedPointer to forward declared class
+
+public:
+ MyClass(); // OK
+ inline ~MyClass() {} // VIOLATION - Destructor must not be inline
+
+private:
+ Q_DISABLE_COPY(MyClass) // OK - copy constructor and assignment operators
+ // are now disabled, so the compiler won't implicitely
+ // generate them.
+};
+//! [4]
+
+//! [5]
+// this QScopedPointer deletes its data using the delete[] operator:
+QScopedPointer<int, QScopedPointerArrayDeleter<int> > arrayPointer(new int[42]);
+
+// this QScopedPointer frees its data using free():
+QScopedPointer<int, QScopedPointerPodDeleter> podPointer(reinterpret_cast<int *>(malloc(42)));
+
+// this struct calls "myCustomDeallocator" to delete the pointer
+struct ScopedPointerCustomDeleter
+{
+ static inline void cleanup(MyCustomClass *pointer)
+ {
+ myCustomDeallocator(pointer);
+ }
+};
+
+// QScopedPointer using a custom deleter:
+QScopedPointer<MyCustomClass, ScopedPointerCustomDeleter> customPointer(new MyCustomClass);
+//! [5]