OOP python questions

Question

Is a class iterable in python (can we iterate through a class)?

Answer 1

A class isn't iterable by default, but you can make instances of it iterable. This is done by using the special methods like __iter__() and __next__(). Example:

class iterableClass:
def __init__(self, string):
self.string = string
self.index = 0

def __iter__(self):
return self # Returns itself, basically iterating itself

def __next__(self):
if self.index >= len(self.string):
raise StopIteration
letter = self.string[self.index]
self.index += 1
return letter

# Sample usage
myString = iterableClass("Iterating Class")

for letter in myString:
print(letter)

Answer 2

interesting.
It got me thinking on how it's useful...

Instead of defining an __iter__ method, I instead subclassed one class to collections.UserList. Then it became basically a custom list class.

how about a list where you can only append?

https://sololearn.com/compiler-playground/cHUw53g69OZf/?ref=app

Answer 3

Use a metaclass as a constructor for your class to get the desired iterable behavior.
https://sololearn.com/compiler-playground/cOAQcq5yLd2P/?ref=app