30 case class Right(v: Val) extends Val

    30 case class Right(v: Val) extends Val

    31 case class Stars(vs: List[Val]) extends Val

    31 case class Stars(vs: List[Val]) extends Val

    32 case class Rec(x: String, v: Val) extends Val

    32 case class Rec(x: String, v: Val) extends Val

    33    

    33    

    34 // some convenience for typing in regular expressions

    34 // some convenience for typing in regular expressions

    37 

    35 

    38 def charlist2rexp(s : List[Char]): Rexp = s match {

    36 def charlist2rexp(s : List[Char]): Rexp = s match {

    39   case Nil => ONE

    37   case Nil => ONE

    40   case c::Nil => CHAR(c)

    38   case c::Nil => CHAR(c)

    41   case c::s => SEQ(CHAR(c), charlist2rexp(s))

    39   case c::s => SEQ(CHAR(c), charlist2rexp(s))