@Test
public void testInfixl() {

  expect(binaryOp.apply(4, 1)).andReturn(3);
  expect(binaryOp.apply(3, 2)).andReturn(1);
  replay();
  Parser<Integer> parser = INTEGER.infixl(isChar('-').retn(binaryOp));
  assertEquals((Object) 1, parser.parse("4-1-2", mode));
}