scala> class T extends CanEqual
-- [E112] Syntax Error: --------------------------------------------------------
1 | class T extends CanEqual
  |       ^
  |       Cannot extend sealed trait CanEqual in a different source file
  |
  | longer explanation available when compiling with `-explain`
1 error found
scala> class T extends CanEqual
-- [E112] Syntax Error: --------------------------------------------------------
1 | class T extends CanEqual
  |       ^
  |       Cannot extend sealed trait CanEqual in a different source file
  |
  | longer explanation available when compiling with `-explain`
1 error found

