User model stacking

[Kevin Bourrillion]

On Wed, Apr 27, 2022 at 9:36 PM Kevin Bourrillion <kevinb at google.com> wrote:

(Type R) e.g. Rational, EmployeeId: the default value is illegal; can't
> even construct it on purpose. Every method on it *should* call
> `checkValid()` first. Might as well repurpose it as a pseudo-null. Bugs
> could be prevented by some analogue of aftermarket nullness analysis.
>

This is me admitting defeat on the rule *I've* meant by "no new nulls". Not
sure if it's how others have used it too.

--
Kevin Bourrillion | Java Librarian | Google, Inc. | kevinb at google.com