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0 pointsgrues-dinner1y ago0 comments

The whole point of a shared_ptr is that you can't delete it out from under other users. You can do exactly what you suggest with a weak_ptr.

A shared_ptr to an object with a deinit() is rather like a weak_ptr in that someone else can "delete" it, and you should check if it's really there, except it can still have some information about things like deinit failures rather than just telling you that the object is deleted.

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17186274401y ago· 1 in thread

In this case it is clearly intended to be deleted under users, so why not use the language feature for that (destructor) instead of inventing yet another level of book-keeping.

grues-dinnerOP1y ago

You can, as long as you don't need to know if/how something within the deinit failed. If you literally just want to know if the item is gone, that's exactly a weak_ptr.

File streams, say, do this by expecting users to close() the file themselves if they care if exceptions happen, but if you destruct without doing that first, any exceptions are caught and don't make it out of the destructor, so they're just gone and you'll never know.

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