Fix #10108: Distinguish between soft and hard union types#10112

Merged

odersky merged 9 commits intoscala:masterfrom

dotty-staging:change-union-types

Oct 31, 2020

Commits on Oct 30, 2020

Fix #10108: Keep an `isSoft` flag in OrTypes
odersky
committed
Fix conditions when to add an AndType in CrossCastAnd
odersky
committed
Treat soft and hard unions differently when widening
odersky
committed
Drop asymmetric widening
odersky
committed
Remove asymmetric option in code and comments

odersky
authored and
liufengyun
committed
Drop CrossCastAnd

odersky
authored and
liufengyun
committed
Drop unreachable case in doctest

odersky
authored and
liufengyun
committed
Fix exhaustivity checks
liufengyun
committed
Refactor flatten to be lazy
liufengyun
committed