[Python-Dev] AC Derby and accepting None for optional positional arguments

[Georg Brandl]

Am 16.01.2014 12:39, schrieb Antoine Pitrou:
> On Thu, 16 Jan 2014 04:42:43 -0500
> Terry Reedy <tjreedy at udel.edu> wrote:
> 
>> On 1/16/2014 3:31 AM, Serhiy Storchaka wrote:
>> > 16.01.14 08:05, Guido van Rossum написав(ла):
>> >> In this specific case it's clear to me that the special-casing of
>> >> negative count is intentional -- presumably it emulates sequence
>> >> repetition, where e.g. 'a'*-1 == ''.
>> >
>> > In this specific case it's contrary to sequence repetition. Because
>> > repeat('a', -1) repeats 'a' forever.
>> 
>> 'Forever' only when the keyword is used and the value is -1.
>> In 3.4b2
>> 
>>  >>> itertools.repeat('a', -1)
>> repeat('a', 0)
>>  >>> itertools.repeat('a', times=-1)
>> repeat('a')
>>  >>> itertools.repeat('a', times=-2)
>> repeat('a', -2)
> 
> Looks like a horrible bug to me. Passing an argument by position should
> mean the same as passing it by keyword!

Indeed, that should be fixed regardless of AC.

Georg