20.04.20 23:33, Andrew Barnert via Python-ideas пише:
> Should this print 1 or 2 or raise StopIteration or be a don’t-care?
>
> Should it matter if you zip(y, x, strict=True) instead?

It should print 2 in both cases. The only way to determine whether the
iterator ends is to try to get its next value. And this value (1) will
lost, because there is no way to return it or "unput" to the iterator.
There is no reason to consume more values, so StopIteration is irrelevant.

There is more interesting example:

     x = iter(range(5))
     y = [0]
     z = iter(range(5))
     try:
         zipped = list(zip(x, y, z, strict=True))
     except ValueError: # assuming that’s the exception you want?
        assert zipped == [(0, 0, 0)]
        assert next(x) == 2
         print(next(z))

Should this print 1 or 2?

The simple implementation using zip_longest() would print 2, but more
optimal implementation can print 1.