Introduce nontoken handling in preliminary transducer
diff --git a/datokenizer.go b/datokenizer.go
index 39596b9..f7339ab 100644
--- a/datokenizer.go
+++ b/datokenizer.go
@@ -305,20 +305,9 @@
os.Exit(1)
}
- /*
- // Allow any epsilon to become a newline
- if !(inSym == tok.epsilon && tok.sigmaRev[outSym] == NEWLINE) &&
-
- // Allow any whitespace to be ignored
- !(inSym != tok.epsilon && outSym == tok.epsilon) &&
-
- // Allow any whitespace to become a new line
- !(tok.sigmaRev[outSym] == NEWLINE) {
-
- }
- */
} else if inSym == tok.epsilon {
- panic("Epsilon transitions not allowed")
+ log.Error().Msg("Epsilon transitions not supported")
+ os.Exit(1)
}
// This collects all edges until arrstate changes
@@ -490,7 +479,7 @@
dat.setBase(t, dat.xCheck(A))
// TODO:
- // Sort the outgoing transitions based onm the
+ // Sort the outgoing transitions based on the
// outdegree of .end
// Iterate over all outgoing symbols
@@ -507,7 +496,7 @@
// Mark the state as being the target of a nontoken transition
if tok.transitions[s][a].nontoken {
- dat.setNonToken(t, true)
+ dat.setNonToken(t1, true)
}
// Check for representative states
@@ -850,3 +839,128 @@
goto FINALCHECK
}
+
+// Match an input string against the double array
+// FSA.
+//
+// Based on Match with additional support
+// for NONTOKEN handling
+func (dat *DaTokenizer) Transduce(input string) bool {
+ var a int
+ var tu uint32
+ var ok, nontoken bool
+
+ t := uint32(1) // Initial state
+ chars := []rune(input)
+ i := 0
+
+ for i < len(chars) {
+ a, ok = dat.sigma[chars[i]]
+
+ // Support identity symbol if character is not in sigma
+ if !ok && dat.identity != -1 {
+ if DEBUG {
+ fmt.Println("IDENTITY symbol", string(chars[i]), "->", dat.identity)
+ }
+ a = dat.identity
+ } else if DEBUG {
+ fmt.Println("Sigma transition is okay for [", string(chars[i]), "]")
+ }
+ tu = t
+ CHECK:
+ nontoken = false
+ t = dat.getBase(tu) + uint32(a)
+
+ // Check if the transition is valid according to the double array
+ if t > dat.getCheck(1) || dat.getCheck(t) != tu {
+
+ if DEBUG {
+ fmt.Println("Match is not fine!", t, "and", dat.getCheck(t), "vs", tu)
+ }
+
+ if !ok && a == dat.identity {
+ // Try again with unknown symbol, in case identity failed
+ if DEBUG {
+ fmt.Println("UNKNOWN symbol", string(chars[i]), "->", dat.unknown)
+ }
+ a = dat.unknown
+
+ } else if a != dat.epsilon {
+ // Try again with epsilon symbol, in case everything else failed
+ if DEBUG {
+ fmt.Println("EPSILON symbol", string(chars[i]), "->", dat.epsilon)
+ }
+ a = dat.epsilon
+ } else {
+ break
+ }
+ goto CHECK
+ } else if dat.isSeparate(t) {
+ // Move to representative state
+ nontoken = dat.isNonToken(t)
+
+ t = dat.getBase(t)
+ } else {
+ nontoken = dat.isNonToken(t)
+ }
+
+ // Transition is fine
+ if a != dat.epsilon {
+ // Character consumed
+
+ if !nontoken {
+ fmt.Print("[", string(chars[i]), "]")
+ }
+ i++
+ }
+
+ if nontoken {
+ fmt.Print("<|>")
+ }
+
+ // TODO:
+ // Prevent endless epsilon loops!
+ }
+
+ if i != len(chars) {
+ if DEBUG {
+ fmt.Println("Not at the end")
+ }
+ return false
+ }
+
+FINALCHECK:
+
+ // Automaton is in a final state
+ if dat.getCheck(dat.getBase(t)+uint32(dat.final)) == t {
+ if dat.isNonToken(t) {
+ fmt.Print("<|>")
+ }
+ return true
+ }
+
+ // Check epsilon transitions until a final state is reached
+ tu = t
+ t = dat.getBase(tu) + uint32(dat.epsilon)
+
+ // Epsilon transition failed
+ if t > dat.getCheck(1) || dat.getCheck(t) != tu {
+ if DEBUG {
+ fmt.Println("Match is not fine!", t, "and", dat.getCheck(t), "vs", tu)
+ }
+ return false
+
+ } else if dat.isSeparate(t) {
+ nontoken = dat.isNonToken(t)
+ // Move to representative state
+ t = dat.getBase(t)
+ } else {
+ nontoken = dat.isNonToken(t)
+ }
+
+ if nontoken {
+ fmt.Print("<|>")
+ }
+
+ goto FINALCHECK
+}