The std::weak_ptr does need a shared_ptr, but that doesn't necessarily
prevent them from creating their own 'weak_reference' class or whatever
that could check on whether what it pointed to was still valid or not.
The case I'm using it for is I have a top level message, with a repeated
set of
A weak_ptr needs a shared_ptr to begin with so all the submessages would
end up being a shared_ptr (creating an impression that they are meant for
shared ownership). In fact, I feel that Protobuf could perhaps change the
generated code to use unique_ptr instead of it's raw pointers to more
I agree that since the model is that the top message owns its submessages,
the idea of shared ownership isn't necessarily useful. But something like a
weak pointer doesn't change the ownership, it would just allow objects to
be responsive to whether the submessage exists or not.
While holding
I think this would be a pretty difficult and invasive change to make,
because the basic memory model used by C++ protobuf is that each message
has sole ownership of its submessages, with no notion of shared ownership.
If we did introduce a change like this, it would also force existing users
to
