Error found:
at tests/purs/failing/NewtypeInstance2.purs:8:1 - 8:54 (line 8, column 1 - line 8, column 54)

  Cannot derive newtype instance for
                        
    Data.Show.Show (X a)
                        
  Make sure this is a newtype.


See https://github.com/purescript/documentation/blob/master/errors/InvalidNewtypeInstance.md for more information,
or to contribute content related to this error.