[Tutor] Python Idioms?

[Mark Lawrence]

On 01/04/2015 14:16, Steven D'Aprano wrote:
> On Wed, Apr 01, 2015 at 12:06:33PM +0100, Mark Lawrence wrote:
>
>> In which case I'll stick with the more-itertools pairwise() function
>> which I pointed out on another thread just yesterday.  From
>> http://pythonhosted.org//more-itertools/api.html
>>
>> <quote>
>> Returns an iterator of paired items, overlapping, from the original
>>
>>>>> take(4, pairwise(count()))
>> [(0, 1), (1, 2), (2, 3), (3, 4)]
>
> I betcha the implementation of pairwise is something really close to:
>
> def pairwise(iterable):
>      it = iter(iterable)
>      return itertools.izip(it, it)
>
> for Python 2, and for Python 3:
>
> def pairwise(iterable):
>      it = iter(iterable)
>      return zip(it, it)
>

Not a bad attempt :)  It's actually.

def pairwise(iterable):
     """Returns an iterator of paired items, overlapping, from the original

         >>> take(4, pairwise(count()))
         [(0, 1), (1, 2), (2, 3), (3, 4)]

     """
     a, b = tee(iterable)
     next(b, None)
     return zip(a, b)

-- 
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence