Python - Way to restart a for loop, similar to "continue" for while loops?

python loops for-loop continue
Georgina picture Georgina · Sep 14, 2010 · Viewed 71.9k times · Source

Basically, I need a way to return control to the beginning of a for loop and actually restart the entire iteration process after taking an action if a certain condition is met.

What I'm trying to do is this:

    for index, item in enumerate(list2):
    if item == '||' and list2[index-1] == '||':
        del list2[index]
        *<some action that resarts the whole process>*

That way, if ['berry','||','||','||','pancake] is inside the list, I'll wind up with:

['berry','||','pancake'] instead.

Thanks!

Answer

Liquid_Fire picture Liquid_Fire · Sep 14, 2010

I'm not sure what you mean by "restarting". Do you want to start iterating over from the beginning, or simply skip the current iteration?

If it's the latter, then for loops support continue just like while loops do:

for i in xrange(10):
  if i == 5:
    continue
  print i

The above will print the numbers from 0 to 9, except for 5.

If you're talking about starting over from the beginning of the for loop, there's no way to do that except "manually", for example by wrapping it in a while loop:

should_restart = True
while should_restart:
  should_restart = False
  for i in xrange(10):
    print i
    if i == 5:
      should_restart = True
      break

The above will print the numbers from 0 to 5, then start over from 0 again, and so on indefinitely (not really a great example, I know).

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