Python constructor attibute missing

Question

I want to print dates in the following format:

23:59:59 Sunday

But all I get is this

23:59:59

This is my code:

    class Counter:
    def __init__(self, start=0):
        self.value = start

    def advance(self):
        self.value = self.value + 1

    def __str__(self):
        return str(self.value)


class CyclicCounter(Counter):

    def __init__(self, period, start=0):
        self.period = period
        Counter.__init__(self, start)

    def advance(self):
        self.value = (self.value + 1) % self.period

    def __str__(self):
        s = Counter.__str__(self)
        return (len(str(self.period - 1)) - len(s)) * '0' + s


class CascadeCounter(CyclicCounter):

    def __init__(self, next, period, start=0):

        CyclicCounter.__init__(self, period, start)
        self.next = next

    def advance(self):
        CyclicCounter.advance(self)
        if self.next and self.value == 0:
            self.next.advance()


class Clock(Counter):
    def __init__(self, h, m, s):
        super().__init__()
        self._h = CyclicCounter(24, h)
        self._m = CascadeCounter(self._h, 60, m)
        self._s = CascadeCounter(self._m, 60, s)

    def advance(self):
        self._s.advance()

    def __str__(self):
        return '{0}:{1}:{2}'.format(self._h, self._m, self._s)


class DayCounter(CyclicCounter):
    _days = ['Sunday', 'Monday', 'Tuesday', 'Wednesday',
             'Thursday', 'Friday', 'Saturday']
    day = ''
    def __init__(self, day='Sunday'):
        self.day = CyclicCounter.__init__(self, day)

    def __str__(self):
        return str(self.day)


class DayClock(Clock):

    def __init__(self, h=0, m=0, s=0, day='Sunday'):
        super().__init__(h, m, s)
        self._d = DayCounter(day)

    def __str__(self):
        return Clock.__str__(self) + ' ' + str(self._d)


if __name__ == '__main__':
    from time import sleep

    clock = DayClock(23, 59, 45)
    threshold = 5
    while threshold > 0:
        print(str(clock) + "\n")
        sleep(1)
        clock.advance()
        threshold -= 1

As far as I can tell I do assign a value on the day attribute as well so I would expect it to be printed to but it doesnt. Specifically, in the main I create a DayClock, and I initialise the _d attribute with a DayCounter instance of the class that takes as input the string value of Sunday.

Answer 1

DayClock doesn't have a __str__() method that adds the day, it just inherits the method from Clock . It should call the inherited method and then concatenate the day name to that.

class DayClock(Clock):

    def __init__(self, h=0, m=0, s=0, day='Sunday'):
        super().__init__(h, m, s)
        self._d = DayCounter(day)

    def __str__(self):
        return Clock.__str__(self) + ' ' + str(self._d)

The DayCounter class also seems to have some serious problems. Shouldn't it use _days.index(day) to provide the start() argument to CyclicCounter ? And the __str__() method should return a string from _days . I'm not going to try to fix all your bugs here, since the question was just about the DayClock class.