[Python-3000] Builtin iterator type

[George Sakkis]

On 11/14/06, Jim Jewett <jimjjewett at gmail.com> wrote:

> Yes, and at first glance, an IterMixin would be nice.  But only at first glance.
>
> (1)  Things that are already iterators won't implement the entire
> newly expanded iteration API.   I don't want people to start
> mechanically replacing
>
>     for var in seq
>
> with
>
>     for var in Iter(seq)
>
> just because they can't remember whether or not it matters.

Short answer: it doesn't. Only if you actually use the new API it matters, e.g.

for var in Iter(it1) + Iter(it2):


> (2)  Some of the functionality in itertools (particularly islice) is
> awkward enough that maybe it should be hidden in a library.  That way
> people are less likely to stumble on it without seeing the
> documentation.

You can argue the same for a gazillion other python features. There's
no way to know that list slicing returns a copy and not a view, or
that numpy arrays do the opposite, without reading the docs.

> (3)  IterMixin would be the only mixin exposed as a builtin -- the
> other mixins must be imported.  The builtin type factories are
> typically the stripped down versions.

That problem is solved if we boost up the existing iter() builtin.

George