[pattern-switch] Opting into totality

[Guy Steele]

> On Sep 3, 2020, at 2:16 PM, Brian Goetz <brian.goetz at oracle.com> wrote:
> 
> That came up in the expression switch exploration.  The thinking then, which I think is still valid, that it is easier to understand the difference when default-totality is attached to the expression versions, because expressions _must_ be total and statements totally make sense to be partial.  

Which, many theorists would say, is an indictment of statements (both generally and in this specific instance).