Brilliant or insane code?

[Ian Kelly]

On Tue, Mar 17, 2015 at 7:14 PM, Dan Sommers <dan at tombstonezero.net> wrote:
> On Wed, 18 Mar 2015 00:35:42 +0000, Mark Lawrence wrote:
>
>> I've just come across this
>> http://www.stavros.io/posts/brilliant-or-insane-code/ as a result of
>> this http://bugs.python.org/issue23695
>>
>> Any and all opinions welcomed, I'm chickening out and sitting firmly
>> on the fence.
>
> According to the article itself, "it relies in an implementation detail
> (the order the zip function iterates over the arrays) to work."  Then
> again, the article also points to the official docs that says that this
> implementation detail is guaranteed.
>
> So it's no worse than depending on some weird but *documented* corner of
> the IEEE-754 or POSIX spec.

In fact, this is also a code recipe found in the itertools
documentation. The official docs don't just guarantee it; they
*recommend* it.

def grouper(iterable, n, fillvalue=None):
    "Collect data into fixed-length chunks or blocks"
    # grouper('ABCDEFG', 3, 'x') --> ABC DEF Gxx"
    args = [iter(iterable)] * n
    return zip_longest(*args, fillvalue=fillvalue)

https://docs.python.org/3.4/library/itertools.html