[Development] Question about QCoreApplicationData::*_libpaths

Kevin Kofler kevin.kofler at chello.at
Sat Jan 23 00:12:30 CET 2016

Marc Mutz wrote:
> But again, CoW can be retrofitted onto any value type (e.g.
> shared_ptr<const T>), while CoW types will never be truly value types.

Again this nonsensical claim that shared_ptr is CoW. I already replied once 
explaining that it is not. Or where do you see a copy on write being done? 
shared_ptr does NOT detach. It is explicitly shared, you have to manually 
deep-copy the contained T object if you need a deep copy. It does track an 
atomic reference count, so it should be possible to implement CoW on top of 
shared_ptr, but shared_ptr by itself is not CoW.

There is no CoW smart pointer in the STL.

        Kevin Kofler

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