operator overloading won't work

operator overloading won't work - Printable Version

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operator overloading won't work - MaartenRo - Aug-04-2020

Hi,

When i run this code i get

(0) + (1) = (2)

while i should get

Rood Groen Blauw + Geel Paars Cyaan = Rood Groen Blauw Geel Paars Cyaan

What am i doing wrong?
Any input is much appreciated!

class MyClass:
    def __init__(self, *args):
        self.Input = args

    def __add__(self, Other):
        Output = MyClass()
        Output.Input = self.Input + Other.Input
        return Output

    def __str__(self):
        Output = ""
        for Item in Self.Input:
            Output += Item
            Output += " "
        return Output

Value1 = MyClass("Rood", "Groen", "Blauw")
Value2 = MyClass("Geel", "Paars", "Cyaan")
Value3 = Value1 + Value2

print("(0) + (1) = (2)"
        .format(Value1, Value2, Value3))

RE: operator overloading won't work - deanhystad - Aug-04-2020

First lets do the format problem. You need to use curly brackets instead of parenthesis in your format string. This is an easy mistake to make when copying code. Depending on the font, {} can look a lot like ().

print("{0} + {1} = {2}".format('a', 'b', 'c'))

Your operator overloading code doesn't work because you use Self instead of self in method __add___. When I ran your code Python told me exactly what and where the error was.

Output:Traceback (most recent call last):
  File "C:\Users\djhys\Documents\python\musings\junk.py", line 21, in <module>
    print("{0} + {1} = {2}"
  File "C:\Users\djhys\Documents\python\musings\junk.py", line 12, in __str__
    for Item in Self.Input:
NameError: name 'Self' is not defined