afl-material: progs/app6.scala@86b2aeae3e98 (annotated)

262 ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	1	def simp(r: Rexp): Rexp = r match {
ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	2	case ALT(r1, r2) => {
343 539b2e88f5b9 updated Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 262 diff changeset	3	(simp(r1), simp(r2)) match {
539b2e88f5b9 updated Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 262 diff changeset	4	case (NULL, r2s) => r2s
539b2e88f5b9 updated Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 262 diff changeset	5	case (r1s, NULL) => r1s
539b2e88f5b9 updated Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 262 diff changeset	6	case (r1s, r2s) => if (r1s == r2s) r1s else ALT(r1s, r2s)
262 ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	7	}
ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	8	}
ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	9	case SEQ(r1, r2) => {
343 539b2e88f5b9 updated Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 262 diff changeset	10	(simp(r1), simp(r2)) match {
262 ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	11	case (NULL, _) => NULL
ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	12	case (_, NULL) => NULL
343 539b2e88f5b9 updated Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 262 diff changeset	13	case (EMPTY, r2s) => r2s
539b2e88f5b9 updated Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 262 diff changeset	14	case (r1s, EMPTY) => r1s
539b2e88f5b9 updated Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 262 diff changeset	15	case (r1s, r2s) => SEQ(r1s, r2s)
262 ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	16	}
ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	17	}
ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	18	case NTIMES(r, n) => NTIMES(simp(r), n)
ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	19	case r => r
7 73cf4406b773 updated Christian Urban <urbanc@in.tum.de> parents: diff changeset	20	}
73cf4406b773 updated Christian Urban <urbanc@in.tum.de> parents: diff changeset	21
117 25999de692b2 added slides Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 93 diff changeset	22	def ders (s: List[Char], r: Rexp) : Rexp = s match {
25999de692b2 added slides Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 93 diff changeset	23	case Nil => r
262 ee4304bc6350 updated handouts Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 117 diff changeset	24	case c::s => ders(s, simp(der(c, r)))
117 25999de692b2 added slides Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 93 diff changeset	25	}
25999de692b2 added slides Christian Urban <christian dot urban at kcl dot ac dot uk> parents: 93 diff changeset	26

author	Christian Urban <christian dot urban at kcl dot ac dot uk>
	Fri, 16 Oct 2015 14:27:20 +0100
changeset 354	86b2aeae3e98
parent 343	539b2e88f5b9
child 399	5c1fbb39c93e
permissions	-rw-r--r--