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Yan Zaretskiy
4,475 PointsIs it possible to force setattr() to discard new attributes?
Coming from C++, I am confused with the amount of flexibility that Python provides in its type system. What if I want to ensure that my class cannot be extended with new attributes by the user? Is it possible?
1 Answer
Chris Freeman
Treehouse Moderator 68,454 PointsIt is possible to overwrite the class method __setattr__() to limit attribute changes and additions (See docs). This [StackOverflow]{http://stackoverflow.com/questions/3603502/prevent-creating-new-attributes-outside-init) question has an example.
You can also set the class variable __slots__ to restrict attribute creation, but there are some caveats as mentioned in this SO response.
More doc info on _slots_