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Python Object-Oriented Python Advanced Objects Multiplication

In __rmul__ why don't we have to turn the self.value into a float and integer like we did in __mul__?

In rmul why don't we have to turn the self.value into a float and integer like we did in mul?

numstring.py
class NumString:
    def __init__(self, value):
        self.value = str(value)

    def __str__(self):
         return self.value

    def __int__(self):
        return int(self.value)

    def __float__(self):
        return float(self.value)

    def __add__(self, other):
        if '.' in self.value:
            return float(self) + other
        return int(self) + other

    def __radd__(self, other):
        return self + other

    def __iadd__(self, other):
        self.value = self + other
        return self.value

    def __mul__(self, other):
        if '.' in self.value:
            return float(self)*(other)
        return int(self) * other

    def __rmul__(self, other):
        return self * other

2 Answers

Greg Kaleka
Greg Kaleka
39,021 Points

Hey Andrew,

I very strongly recommend you go back and watch the video just before this challenge, because Kenneth explains this in detail for __add__ and __radd__.

The same holds true for __mul__and __rmul__: you could write it all out, but you don't need to, because Python will ultimately just call the __mul__ method from the __rmul__ method.

Please go back and watch the video again, though, because Kenneth does a great job explaining it, starting at around 2:30 and ending around 4:30.

Cheers :beers:

-Greg