Python generators

Question

def count_to_5():
for i in range(1,6):
yield i
c = count_to_5()
n = 0
for i in c:
n += 1
print(n)
for i in c:
n -= 1
print(n)

here, I thought the the output would be -
5
0
but it is -
5
5

why? can you explain, guys?

Answer 1

Generators become exhausted when the bottom of the function is reached.

A for loop calls 'next' on your generator.

The second loop runs, but since the generator c is already 'empty', it stops rightaway and no subtraction is executed.

Answer 2

Oh no!! 😫
HonFu, Thanks, anyway 😍

Answer 3

You can make a new generator anytime!

For example if in the second loop you write...

for i in count_to_5():
...

... you create a new generator and get the result you expect.

Answer 4

HonFu, ya, did so.. 😊