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Python Object-Oriented Python Advanced Objects Multiplication

Is mul just the same as add but with a multiplication sign?

It would seem like I would just substitute the plus sign with an asterisk and be on my merry way but it's not working.

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.value) * other
        return int(self.value) * other

    def __rmul:
        return self.value * other

1 Answer

Steven Parker
Steven Parker
218,639 Points

You have the right idea, but you haven't followed the example of the "add" methods exactly:

  • you have "self.value" where the other methods have just "self"
  • one method name has the "dunder" (double underscores) on just one side of the name instead of both