code: @Test public void testLiteralWithPercent() throws ScanException {
  {
      List tl=new TokenStream("hello\\%world").tokenize();
      List<Token> witness=new ArrayList<Token>();
      witness.add(new Token(Token.LITERAL,"hello%world"));
      assertEquals(witness,tl);
    }
  {
      List tl=new TokenStream("hello\\%").tokenize();
      List<Token> witness=new ArrayList<Token>();
      witness.add(new Token(Token.LITERAL,"hello%"));
      assertEquals(witness,tl);
    }
  {
      List tl=new TokenStream("\\%").tokenize();
      List<Token> witness=new ArrayList<Token>();
      witness.add(new Token(Token.LITERAL,"%"));
      assertEquals(witness,tl);
    }
  }
  