I agree with that assessment of Pin. That's why the second post I linked to presents a set of features that would make it as easy to use as mutability (pinning

I agree with that assessment of Pin. That's why the second post I linked to presents a set of features that would make it as easy to use as mutability (pinning is really the dual of immutability: an immutable place cannot be assigned into, whereas a pinned place cannot be moved out of).