| author | Christian Urban <christian dot urban at kcl dot ac dot uk> |
| Sun, 21 Aug 2016 00:38:32 +0100 | |
| changeset 408 | 5322e1c46890 |
| parent 407 | 4b454a6d1814 |
| child 409 | fb8ee3f58d19 |
| progs/rev.scala | file | annotate | diff | comparison | revisions |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/progs/rev.scala Sun Aug 21 00:38:32 2016 +0100 @@ -0,0 +1,8 @@ +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)) +}