Re: Gee Functional iterators

[Martin DeMello <martindemello gmail com>]

On Mon, Jul 26, 2010 at 2:42 AM, Maciej Piechotka <uzytkownik2 gmail com> wrote:
>
> I'm sorry but I fail to see how does it work. Could you show what
> exactly map or other transformation would look like (even in terms of
> interface?).

* Iterable.map() would return View object that holds an iterator and a
list of [function, closure] pairs, where function is either `map` or
`filter` (or maybe split `filter` into `select` and `reject`).

* View.map(closure) would add the closure to the chain.

* Calling `next` on the View would call `next` on the iterator,
retrieve the value and apply the chain of operations to it, then yield
it.

Having a single View with a chain of operations rather than a nested
set of Views each with a single operation makes implementing `filter`
easier, even though nesting Views has more conceptual elegance. Not
sure how fast this would be, but it's very space-efficient.

martin