Python Stop Iteration
StopIteration
To prevent the iteration to go on forever, we can use the
StopIteration statement.
In the __next__() method, we can add a terminating condition to raise an error if the iteration is done a specified number of times:
Example
Stop after 20 iterations:
class MyNumbers:
def __iter__(self):
self.a =
1
return self
def __next__(self):
if self.a <= 20:
x = self.a
self.a += 1
return x
else:
raise StopIteration
myclass =
MyNumbers()
myiter = iter(myclass)
for x in myiter:
print(x)
Try it Yourself »
