add function to quad tree to turn items into strings (for later saving to file)

fcore/parser/all-dfa.sml

@@ -0,0 +1,35 @@
+structure AllDfa =
+struct
+  type t = {curInt: int, curSpace: int, curBrace: int, lastInt: int,
+  lastSpace: int, lastBrace: int}
+
+  val initial: t =
+    {
+      curInt = IntDfa.start,
+      curSpace = SpaceDfa.start,
+      curBrace = BraceDfa.start,
+
+      lastInt = ~1,
+      lastSpace = ~1,
+      lastBrace = ~1
+    }
+
+  fun areAllDead ({curInt, curSpace, curBrace, ...}: t) =
+    curInt = 0 andalso curSpace = 0 andalso curBrace = 0
+
+  fun update (chr, dfa, pos) =
+    let
+      val {curInt, curSpace, curBrace, lastInt, lastBrace, lastSpace} = dfa
+
+      val curInt = IntDfa.next (curInt, chr)
+      val curSpace = SpaceDfa.next (curSpace, chr)
+      val curBrace = BraceDfa.next (curBrace, chr)
+
+      val lastInt = if IntDfa.isFinal curInt then pos else lastInt
+      val lastSpace = if SpaceDfa.isFinal curSpace then pos else lastSpace
+      val lastBrace = if BraceDfa.isFinal curBrace then pos else lastBrace
+    in
+      {curInt = curInt, curSpace = curSpace, curBrace = curBrace, lastInt =
+      lastInt, lastBrace = lastBrace, lastSpace = lastSpace}
+    end
+end