Widget wag = * new widget ()

Question

I just came across a C ++ SDK that heavily uses this really weird pattern *new. I don’t understand why they do this.

What is the point of building objects using * new, for example. Widget wag = *new Widget();?

Update: I wonder what they are actually doing XPtr<T> p = *new T;- should be the semantics of some kind of smart pointer magic. Still doesn't make much sense. I am really sure that the SDK is of high quality.

Answer 1

It creates a new object and then copies it. The pointer to the source object is discarded, so a memory leak may occur.

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Answer 2

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Answer 3

:

Widget wag = *(new Widget());

// or
Widget wag;

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Answer 4

commom , ref, , IncRef:

SmartPtr<Type> ptr = new Type();

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SmartPtr<Type> ptr = *new Type();

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Answer 5

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int &a = *new int();
delete &a;

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template<typename T>
struct XPtr {
    T *ptr;
    XPtr(T &t):ptr(&t) { }
    ~XPtr() { delete ptr; }
};

...
XPtr<T> p = *new T;

Or even more complex, with reference counting - so that p can be copied, and XPtr keeps track of all its copies, etc.