--- a/progs/display/thompson2.scala Tue Jul 21 00:12:34 2020 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,43 +0,0 @@
-// Thompson Construction (Part 2)
-
-// some more type abbreviations
-type NFAtrans = (TState, Char) :=> Set[TState]
-type eNFAtrans = (TState, Option[Char]) :=> Set[TState]
-
-
-// for composing an eNFA transition with a NFA transition
-implicit class RichPF(val f: eNFAtrans) extends AnyVal {
- def +++(g: NFAtrans) : eNFAtrans =
- { case (q, None) => applyOrElse(f, (q, None))
- case (q, Some(c)) =>
- applyOrElse(f, (q, Some(c))) | applyOrElse(g, (q, c)) }
-}
-
-// sequence of two NFAs
-def NFA_SEQ(enfa1: NFAt, enfa2: NFAt) : NFAt = {
- val new_delta : eNFAtrans =
- { case (q, None) if enfa1.fins(q) => enfa2.starts }
-
- eNFA(enfa1.starts, new_delta +++ enfa1.delta +++ enfa2.delta,
- enfa2.fins)
-}
-
-// alternative of two NFAs
-def NFA_ALT(enfa1: NFAt, enfa2: NFAt) : NFAt = {
- val new_delta : NFAtrans = {
- case (q, c) => applyOrElse(enfa1.delta, (q, c)) |
- applyOrElse(enfa2.delta, (q, c)) }
- val new_fins = (q: TState) => enfa1.fins(q) || enfa2.fins(q)
-
- NFA(enfa1.starts | enfa2.starts, new_delta, new_fins)
-}
-
-// star of a NFA
-def NFA_STAR(enfa: NFAt) : NFAt = {
- val Q = TState()
- val new_delta : eNFAtrans =
- { case (Q, None) => enfa.starts
- case (q, None) if enfa.fins(q) => Set(Q) }
-
- eNFA(Set(Q), new_delta +++ enfa.delta, Set(Q))
-}