diverge() like a clone()?

[getify]

Is diverge() like a clone()? Why not call it clone?

And is the diverging/cloning shallow or deep?

[erights]

Staying with the Map example for concreteness.

I would expect x.clone() to produce something of the same type as x. x.diverge() is not like x.clone(), in that x.diverge() always results in a new mutable Map, even when x is a ReadOnlyMap or a FixedMap.

It is shallow, because it is only about the collection, not the values contained in the collection.

[getify]

Is it an expected use-case that you'll want to go from a read-only or fixed map back to a mutable map so you could make a mutation and then roundtrip right back to the read-only/fixed version?

I'm trying to conceptualize the usage of these data structures vs the "immutable data structures" proposal.