Does python have conditional code interpretation?

Question

I was wondering if python has something like conditional code interpretation. Something like this:

x = True
if x:
    for i in range(0, 10):
else:
    for i in range(0, 100):
# ------------------------------
        print(i) # this is the code inside either one these for loop heads

I know I could do this:

x = True
if x:
    for i in range(0, 10):
        print(i)
else:
    for i in range(0, 100):
        print(i)

But in my case, I have a lot of for-loop code and that wouldn't be a very good solution.

No, it does not. What you could do here though is `rng = range(10) if x else range(100)` then `for i in rng: ..` — juanpa.arrivillaga, May 05 '20 at 22:33
If you're going to use a variable anyway then just set it to `10` or `100`, and use that variable in the `range`. — Jongware, May 05 '20 at 22:38

score 3 · Accepted Answer · answered May 05 '20 at 22:36

3

You can always do:

x = True

for i in range(0,10) if x else range(0, 100):
    print(i)

answered May 05 '20 at 22:36

Andrej Kesely

168,389
15
48
91

John Kugelman · Answer 2 · 2020-05-05T22:47:32.523

No, it doesn't have that syntax. You could achieve the same goal through other means, though.

For example, extract the part that varies (10 versus 100) from the common part (the for in range(...) loop):

limit = 10 if x else 100

for i in range(limit):
    print(i)

Or save one of two different ranges in a variable and loop over that:

numbers = range(0, 10) if x else range(0, 100)

for i in numbers:
    print(i)

Or extract the loop to a function that performs an arbitrary action each iteration:

def loop(limit, action):
    for i in range(limit):
        action(i)

loop(10 if x else 100, lambda i: print(i))

score 0 · Answer 3 · answered May 05 '20 at 22:34

0

If you want you could do this.

x = True
for i in range(0, (10 if x else 20)):
    print(i)

Here the if else statement work like this result_if_true if condition else result_if_false.

answered May 05 '20 at 22:34

Zenocode

656
7
19

score 0 · Answer 4 · answered May 05 '20 at 22:36

0

if x:
    my_iter = range(0, 10)
else:
    my_iter = range(0, 100)
for i in my_iter:
     print(i)

answered May 05 '20 at 22:36

Błotosmętek

12,717
19
29

2

Please add a bit of explanation and context around your solution. – MegaIng May 05 '20 at 23:47

Does python have conditional code interpretation?

4 Answers4