Python - Way to restart a for loop, similar to “continue” for while loops? [duplicate]

Answer 1

continue works in for loops also.

>>> for i in range(3):
...     print 'Before', i
...     if i == 1:
...             continue
...     print 'After', i
... 
Before 0
After 0
Before 1
# After 1 is missing
Before 2
After 2

Answer 2

Continue will work for any loop.

Answer 3

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).

Answer 4

def remove_adjacent(nums):
     return [a for a,b in zip(nums, nums[1:]+[not nums[-1]]) if a != b]

example = ['berry','||','||','||','pancake']

example = remove_adjacent(example)
print example
""" Output:
['berry', '||', 'pancake']
"""

And by the way this is repeating of Remove adjacent duplicate elements from a list

Answer 5

some action that resarts the whole process

A poor way to think of an algorithm.

You're just filtering, i.e., removing duplicates.

And -- in Python -- you're happiest making copies, not trying to do del. In general, there's very little call to use del.

def unique( some_list ):
    list_iter= iter(some_list)
    prev= list_iter.next()
    for item in list_iter:
        if item != prev:
            yield prev
            prev= item
    yield prev

list( unique( ['berry','||','||','||','pancake'] ) )

Answer 6

while True:
    for i in xrange(10):
        if condition(i):
            break
    else:
        break

That will do what you seem to want. Why you would want to do it is a different matter. Maybe you should take a look at your code and make sure you're not missing an obvious and easier way to do it.