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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
//! [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 implicitly
// 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]
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