131     def parse(tsb: List[Token]) = tsb match {

   131     def parse(tsb: List[Token]) = tsb match {

   132         case T_STRING(s) :: rest => Set((s, rest))

   132         case T_STRING(s) :: rest => Set((s, rest))

   133         case _ => Set()

   133         case _ => Set()

   134     }

   134     }

   135 }

   135 }

   136 

   137 

   137 

   138 

   138 // WHILE Language Parsing

   139 // WHILE Language Parsing

   139 lazy val AExp: Parser[List[Token], AExp] =

   140 lazy val AExp: Parser[List[Token], AExp] =

   140   (Te ~ T_OP("+") ~ AExp).map{ case x ~ _ ~ z => Aop("+", x, z): AExp } ||

   141   (Te ~ T_OP("+") ~ AExp).map{ case x ~ _ ~ z => Aop("+", x, z): AExp } ||