I've been converting a bunch of Python to Racket lately, and I have a
lot of loops that use break and continue. I end up turning them into:
(let/ec break
(for (...)
(let/ec continue
; do some work
(when this-iteration-isn't-what-i-want
(continue))
; do more expensive work
(when found-what-i-want
(break what-i-want)))))
I thought it would be nice if the let/ec's could be integrated with
for, so that you could instead write:
(for (#:ec break
...
#:ec continue)
; ...same as above...
In an attempt to help convey the behavior I want, I threw this patch together:
https://github.com/jkominek/racket/commit/b291a0b994c679445b3210bd3efba8c6cea867e4
I feel it behaves reasonably when using for and for/fold, but for/list
doesn't behave in any way I'd hope for.
Ideally somebody who understands for's implementation will agree that
this is a great idea, and go make it all work nicely. :) Failing that
I'm open to suggestions for how to make it behave better, in a fashion
which would make it appropriate for inclusion.
--
Jay Kominek
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