🔒 How do i delegate a magic method from a constructor parameter to the class

[frosty bay]

basically i am trying to golf this code

class A:
    def __init__(self, data: List):
        self.data = data
    def __iter__(self):
        return iter(self.data)

into something like this

class A:
    def __init__(self, data: List):
        self.data = data
        self.__iter__ = data.__iter__

but python doesn't recognise the magic method and says the object is not iterable. is there any way to do this?

[placid steeple]

@frosty bay

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[unborn lark]

you're trying to bind a method late, i googled that concept and found this which seems to work well
https://stackoverflow.com/a/33285227

not sure if it works precisely for your use case though...

[novel elbow]

I thought the issue might be that __iter__ is on the class not the object

!e

class A:
    def __init__(self, data: list):
        self.data = data
        type(self).__iter__ = data.__iter__

a = A([1, 2])
print(iter(a))

this seems to work?

[placid steeple]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

<list_iterator object at 0x7ff98cfc3910>

[unborn lark]

binding methods on class objects instead of instances does work, but the impression i get is that you can no longer have more than 1 instance

[novel elbow]

!e

class A:
    def __init__(self, data: list):
        self.data = data
        type(self).__iter__ = lambda self: iter(self.data)

a = A([1, 2])
print(iter(a))

[placid steeple]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

<list_iterator object at 0x7fb1887a77c0>

[novel elbow]

Would this solve the problem?

[frosty bay]

yea, not exactly what i was looking for but if that's the best you can do with python it's good, thanks

!close

[placid steeple]

Python help channel closed

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