An hour ago, Greg Hendershott wrote:
> In generator.rkt I notice an early version that didn't support
> multiple values. The new version does, keeping a "yielder" proc in a
> parameter.
>
> Could a single-valued generator yield be faster enough? Or am I
> misapplying my misunderstanding? :)
That's not the main difference between the two. It's an earlier
experiment where the `yield' is bound staticaly as a syntax parameter
instead of a dynamic one. The resulting generator facility is closer
to python, where `yield' must appear in the body of the generator.
So, for example, you can't write some helper for generators like
(define (yield-3 n)
(yield (sub1 n))
(yield n)
(yield (add1 n)))
I think that it's not as bad as python, since you can still write such
a helper and pass `yield' as an argument. (At least as much as I
tried, I couldn't get python to use it as a value.)
Our assumption at the time was that the cost of the parameter is much
smaller than the continuation, but we never really tried to measure
it.
--
((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay:
http://barzilay.org/ Maze is Life!
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