[Python-ideas] PEP 479: Change StopIteration handling inside generators

[Juancarlo Añez]

On Tue, Nov 25, 2014 at 5:26 PM, <random832 at fastmail.us> wrote:

> def pairs(x):
>     i = iter(x)
>     while True:
>         yield next(i), next(i)
>

That's not too pythonic, and trying to support non-pythonic code while
evolving the language is a dead-end street.

The web documents pythonic ways to obtain pairs from an iterable:

def pairs(x):
    i = iter(x)
    return zip(i, i)

Or even:

def pairs(x):
     return zip(*[iter(x)]*2)

The usual way of dealing with an odd number of elements is to use
zip_longest.

I don't remember seeing documented that raising StopIteration will cancel
more than one iterator. If it's undocumented, then code that relies on the
non-feature is broken.

Cheers,

-- 
Juancarlo *Añez*
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