| author | Christian Urban <christian dot urban at kcl dot ac dot uk> |
| Mon, 20 Oct 2014 00:28:03 +0100 | |
| changeset 290 | 3a2fa69ea675 |
| parent 261 | 24531cfaa36a |
| child 399 | 5c1fbb39c93e |
| permissions | -rw-r--r-- |
|
261
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
diff
changeset
|
1 |
def OPT(r: Rexp) = ALT(r, EMPTY) |
| 7 | 2 |
|
|
261
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
diff
changeset
|
3 |
def NTIMES(r: Rexp, n: Int) : Rexp = n match {
|
|
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
diff
changeset
|
4 |
case 0 => EMPTY |
|
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
diff
changeset
|
5 |
case 1 => r |
|
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
diff
changeset
|
6 |
case n => SEQ(r, NTIMES(r, n - 1)) |
|
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
diff
changeset
|
7 |
} |
|
24531cfaa36a
updated handouts
Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
93
diff
changeset
|
8 |