code: public static NFA<Integer> createNFA(Scope<NFAState<Integer>> scope, String expression, int token, Option... options)
      {
          if (regexParser == null)
          {
              regexParser = RegexParserFactory.newInstance();
          }
          return regexParser.createNFA(scope, expression, token, options);
      }
docs: Creates an NFA from regular expression
  @param scope
  @param expression
  @param token Token marks the accepting state with unique identifier
  @param options
  @return