can't find: x in testdata/typesig.reject.lc:6:6:
x :: x
     ^
------------ trace
'X :: Type
X :: X
case'X :: forall (a :: X -> Type) -> a 'X -> forall (b :: X) -> a b
match'X :: forall (a :: Type -> Type) -> a X -> forall b -> a b -> a b
!can't find: x in testdata/typesig.reject.lc:6:6:
x :: x
     ^
------------ tooltips
4:6-4:7
    Type | Type | Type | Type | Type
4:6-4:11
    Type
4:10-4:11
    X