gistfile1.txt

type alias RDoc a = { a | id : Int }
type alias RUser = RDoc { userName : String }
type alias RGroup = RDoc { groupName : String }


type RSelectedDoc
  = RSelectedUser RUser
  | RSelectedGroup RGroup


rselectedDocToDoc : RSelectedDoc -> RDoc a
rselectedDocToDoc selectedDoc = 
  case selectedDoc of
    RSelectedUser user -> { id = user.id }
    RSelectedGroup group -> { id = group.id }