Python Tutorial range function question

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Python Tutorial range function question - HawkeyeKnight - Sep-27-2018

I am working though the Python Tutorial. In the section after the section on the range function, which covers using "break", there is the following code-

for n in range(2, 10):
	for x in range(2, n):
	   if n % x == 0:
	      print(n, 'equals', x, '*', n//x)
	      break
	else:
	    print(n, 'is a prime number')

Which results in the following -

2 is a prime number
3 is a prime number
4 equals 2 * 2
5 is a prime number
6 equals 2 * 3
7 is a prime number
8 equals 2 * 4
9 equals 3 * 3

My problem is the second line of code where n == 2. The range function start and stop values are equal, i.e. range(2,2), which I would have expected to result in an error. Since it does not, I am guessing it results in a null [] value. If so, I do not understand how the modulus operation in the next line does not result in an error. Can someone walk me through this. I know it works, just cannot see how.

RE: Python Tutorial range function question - buran - Sep-27-2018

(Sep-27-2018, 05:19 AM)HawkeyeKnight Wrote: I am guessing it results in a null [] value

To be precise, that is not null, but empty list (in python2) or empty range object in python3.
on line 3 it try to iterate over empty object, so it just skip the whole body of the loop (i.e. it does not iterate at all) and goes to line 6

RE: Python Tutorial range function question - ThiefOfTime - Sep-27-2018

like buran said, sry had to correct my post