Attic/rev.scala
author Christian Urban <christian.urban@kcl.ac.uk>
Sat, 09 Nov 2024 06:23:35 +0000
changeset 972 ebb4a40d9bae
parent 742 b5b5583a3a08
permissions -rw-r--r--
updated

def rev(r: Rexp) : Rexp = r match {
  case ZERO => ZERO
  case ONE => ONE
  case CHAR(c) => CHAR(c)
  case ALT(r1, r2) => ALT(rev(r1), rev(r2))
  case SEQ(r1, r2) => SEQ(rev(r2), rev(r1))
  case STAR(r) => STAR(rev(r))
}