public ComparedToDateValidator()
 {
     When(Field("left", Has.Value()) & Field("right", Has.Value()))
     .Then("left", ComparedTo("right", t => Must.Be.LessOrEqualTo((DateTime)t)));
 }
 public ComparedToIntegerValidator()
 {
     When(Field("left", Has.Value()) & Field("right", Has.Value()))
     .Then("left", ComparedTo("right", t => Must.Be.LessOrEqualTo((int)t)));
 }