That's the part I was missing, not the blessing, initially.

For the scalar, it is obvious that assignment to it doesn't change the container. For the hash, I was thinking "initialization" in C++ or reference-based things like in Java and Smalltalk, expecting assigning one hash to another to change the object's identity too.

I see now that assignment of a list (even if that's where you are declaring it) to a hash repopulates it but doesn't change its identity. In that respect it's no different than a scalar.

That's what I get for working on stuff late at night.

—John