One-time actions when iterating

One-time actions when iterating - Printable Version

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One-time actions when iterating - ClassicalSoul - Apr-23-2020

Please note I've made a substantive edit to my original post

Suppose you had the following code, where x is an iterable:

for i in x:
    # do thing 1
    # do thing 2
    if <condition>:
        # do thing 3
        # do thing 4
        continue

But after the condition is met the first time you no longer wish to do thing 4. We could try:

x_iter = iter(x)

for i in x:
    # do thing 1
    # do thing 2
    if <condition>:
        # do thing 3
        # do thing 4
        break

for i in x:
    # do thing 1
    # do thing 2
    if <condition>:
        # do thing 3

But of course we would be repeating code. My question is whether there some shortcut to what I do in the second example.

RE: One-time actions when iterating - bowlofred - Apr-23-2020

Is there a reason you wouldn't just add another conditional?

thing_4_done = False
for i in x:
    # do thing 1
    # do thing 2
    if <condition>:
        # do thing 3
        if not thing_4_done:
            # do thing 4 first time condition is met
            thing_4_done = True