https://bugs.kde.org/show_bug.cgi?id=386134
--- Comment #2 from Roman <dism...@gmail.com> ---
See, this cast function is very tricky. Let's imagine such an hierarchy:
class Bar : public QGraphicsItem
{
virtual int type() const Q_DECL_OVERRIDE {return Type;}
enum { Type = UserType + 1};
};
class Foo : public Bar
{
virtual int type() const Q_DECL_OVERRIDE {return Type;}
enum { Type = UserType + 2};
};
Foo *f = new Foo();
Bar *b = f;
b->type() == f->type();
Because the type() function is virtual in both cases you will get the same
result from Foo::type(). This looks obvious. But what if i want use
qgraphicsitem_cast like this:
QGraphicsItem *p = new Foo();
Bar *parent = qgraphicsitem_cast<Bar *>(p);
It will not work! qgraphicsitem_cast can only cast to Foo in this case. If i
want to cast to Bar i must not to reimplement the type() function in Foo.
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