Ruby

Data objects with at least one member are currently automatically frozen on construction, and shareable if all members are shareable. However, a Data object with no members is not frozen on construction. I would expect such an object similarly to be frozen (and also shareable since it has no non-shareable members).

Foo = Data.define(:foo)
Foo.new(1).frozen? # => true

Bar = Data.define
Bar.new.frozen? # => false