python operator overload and friends

Question

I wanted to know if anyone could give me an example of how to overload an operator within a class, in my case the + operator. Could I define a function (not a class method) that does it? I'm a newbie so I don't really know how to do it.

Thanks

Being a newbie doesn't really explain why you're not searching. No offense meant - it's generally in one's best interest to search before asking, as one usually gets more answers in less time. — , Mar 25 '11 at 22:01
Covered here: http://stackoverflow.com/questions/1552260/rules-of-thumb-for-when-to-use-operator-overloading-in-python — Tom Zych, Mar 25 '11 at 22:30

score 3 · Answer 1 · answered Mar 25 '11 at 22:06

3

Define its __add__() method.

See here.

answered Mar 25 '11 at 22:06

Joril

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score 2 · Accepted Answer · answered Mar 25 '11 at 22:06

class MyNum(object):
    def __init__(self, val):
        super(MyNum,self).__init__()
        self.val = val

    def __add__(self, num):
        return self.__class__.(self.val + num)

    def __str__(self):
        return self.__class__.__name__ + '(' + str(self.val) + ')'

print(MyNum(3) + 2)   # -> MyNum(5)

score 2 · Answer 3 · answered Mar 25 '11 at 22:08

2

When in doubt of the basics: manual. http://docs.python.org/reference/datamodel.html

answered Mar 25 '11 at 22:08

JohnMetta

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python operator overload and friends

3 Answers3

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