itertools to iter transition (WAS: Pre-PEP: Dictionary accumulator methods)

[George Sakkis]

"Steven Bethard" <steven.bethard at gmail.com> wrote:
>
> [snip]
>
> I guess the real questions are[1]:
> * How much does iter feel like a type?
> * How closely are the itertools functions associated with iter?
>
> STeVe
>
> [1] There's also the question of how much you believe in OO tenets like
> "functions closely associated with a type should be members of that type"...

I would answer positively for both: iter does feel like a type conceptually and (most, if not all)
itertools would be suitable methods for such a type. Here I am referring to 'type' more as an
interface (or protocol; i'm not sure of the difference) rather than a concrete class, so whether the
result of iter is an iterator or a generator object is of little importance as long as it works as
expected (that it, whether it makes calls to next() or __getitem__() becomes a hidden implementation
detail).

If iter was a type, it would also be neat to replace some itertool callables with special methods,
as it has been mentioned in another thread (http://tinyurl.com/6mmmf), so that:
iter(x)[a:b:c] := itertools.islice(iter(x),a,b,c)
iter(x) + iter(y) := itertools.chain(iter(x), iter(y))
iter(x) * 3 := itertools.chain(* itertools.tee(iter(x), 3))

George