Why does argparse return None instead of [] if an append action isn't used?

[Adam Funk]

On 2015-01-26, Peter Otten wrote:

> Adam Funk wrote:
>
>> On 2015-01-09, Ned Batchelder wrote:
>> 
>>> On 1/9/15 9:44 AM, Adam Funk wrote:
>>>> This makes it a bit more trouble to use:
>>>>
>>>>    if options.bar:
>>>>       for b in options:bar
>>>>          do_stuff(b)
>>>>
>>>> instead of
>>>>
>>>>    for b in options.bar
>>>>       do_stuff(b)
>>>
>>> This doesn't answer why the value defaults to None, and some people may
>>> recoil at it, but I've used:
>>>
>>>      for b in options.bar or ():
>>>          do_stuff(b)
>> 
>> Do you mean "for b in options.bar or []:" ?
>
> Doesn't matter; in the context of a for loop any empty iterable would do.

Of course it would.  Doh!


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