Python: Method in class that returns instance of itself throwing NameError
I’m trying to create a method in a class that returns a new instance of itself however I keep getting
NameError: name 'CLASSNAME' is not defined. This only happens when I add the type annotation that the method returns and instance of itself. If I don’t do this, then I don’t get the compiler error and the function works as expected. Obviously it’s better to have the correct type on the function, so how can I annotate the function to return the same class?
This issue is resolved natively in Python 4.0+ but in previous versions, you’ll have to import
from __future__ import annotations.
Here’s an example that works without the annotation, breaks with the annotation, and is then fixed with the annotation so long as you import
from __future__ import annotations class Point: x: float y: float def __init__(self, x=0.0, y=0.0): self.x = x self.y = y def clone(self) -> Point: return Point(self.x, self.y) point = Point(1, 1) cloned_point = point.clone() print(cloned_point)
did this help?
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