| author | Christian Urban <urbanc@in.tum.de> | 
| Tue, 20 Nov 2018 13:37:40 +0000 | |
| changeset 608 | 75edca6dd731 | 
| parent 436 | 9213b8298ca9 | 
| permissions | -rw-r--r-- | 
| 415 | 1 | def ders2(s: List[Char], r: Rexp) : Rexp = (s, r) match {
 | 
| 2 | case (Nil, r) => r | |
| 3 | case (s, ZERO) => ZERO | |
| 4 | case (s, ONE) => if (s == Nil) ONE else ZERO | |
| 5 | case (s, CHAR(c)) => if (s == List(c)) ONE else | |
| 6 | if (s == Nil) CHAR(c) else ZERO | |
| 7 | case (s, ALT(r1, r2)) => ALT(ders2(s, r2), ders2(s, r2)) | |
| 436 
9213b8298ca9
updated
 Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 
415diff
changeset | 8 | case (c::s, r) => ders2(s, simp(der(c, r))) | 
| 261 
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updated handouts
 Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 
93diff
changeset | 9 | } |