Start a new iteration of a loop from a different function in the loop [python]

Just make function_in_main return when your if statement is true. when it returns, the loop will move on to the next iteration and then re-call function_in_main.

Maybe try raising an exception:

def function_in_main():
    if #something happens:
        raise Exception

def main():
    n = 1
    for i in range(len(alist)): 
        print ('step ', n)
        try:
            x()
        except Exception:
            continue

        n += 1
main()

You can specify or make whatever type of exception you want.

Here is an example:

def function_in_main(x):
    return x=='Whopee'         # will return True if equal else False

def main():
    alist=['1','ready','Whopee']
    for i,item in enumerate(alist, 1): 
        print ('step {}, item: "{}" and {}'.format(i,item,function_in_main(item)))     

main()

Prints:

step 1, item: "1" and False
step 2, item: "ready" and False
step 3, item: "Whopee" and True

Note the use of enumerate rather than manually keeping a counter.

Sure you're not thinking of a while loop or something? It's a little tough to see what you're getting at…

def your_function():
    #…do some work, do something to something else
    if something_is_true:
        return True
    else:
        return False

def main():
    condition = True
    for i in range(len(your_list)):
        while condition:
            print "Step: %d" % i
            your_function()

Only when your_function returns False will the loop in main continue, otherwise it will stay within the while loop.