> On Aug 22, 2020, at 2:06 PM, Brian Goetz <brian.go...@oracle.com> wrote: > . . . >> >> Option 1: If the type of the switch expression is an enum or a sealed type, >> then it is a static error if the patterns are not at least optimistically >> total. **This would be an incompatible change with respect to existing >> switches on enum types.** > > Actually, as stated, this is not inconsistent -- for switch *expressions*. > We added switch expressions in Java 12 and required that they be total, and, > when the target is an enum, we nodded to optimistic totality, by not > requiring a `default` when the cases were optimistically total. Where we > don't have an equivalent story is for switch *statements*, which have always > been partial -- and for which partiality is reasonable (just as an `if` > without an `else` is reasonable.) And the story for optimistic totality does > not scale quite as well as we'd hoped to sealed types, for a few reasons:
Yes, this was an error on my part; I meant to write "Option 1: If the type of the switch statement is . . .”
