On Jun 4, 2014, at 1:29 PM, Timothy Baldridge <[email protected]> wrote:
> Although your original complaint was about clojure seqs being lazy. It should > be noted that reducers are also lazy down to the point of a fold or reduce, > so I'm not sure what you're really getting there. It wouldn't be hard at all > to write map, filter, remove, etc. in terms of list operations. Perhaps > that's what you're looking for? If I understand your original complaint, you > want map, filter, etc, to be eager. > True, my original concern was (and my main concern still is) to avoid crashes (in this case, stack overflow errors) that stem from unexpected (to me) consequences of laziness. Those problems could indeed be solved by rewriting map and filter etc, or (easier) by "wringing out the laziness" wherever it arises, e.g. by forcing everything to be a vector (or a list, as you suggest). It's a little cumbersome to do this everywhere, though, and I was wondering if there was an existing library or approach for this issue. Then, however, it was suggested that I could have my cake and another kind of cake too, by using reducers. The suggestion was that this could banish the laziness-related issues while also providing significant performance improvements. Sounds good to me! I'm still working on getting my current project to behave well using reducers, but it seems promising. > > On the other hand, time spent learning how lazy seqs work, and the caveats > involved will make it easier for you to understand the code produced by the > rest of the community. So perhaps that's the better option. I agree that it's important to understand lazy sequences, and I do think I understand the core concepts reasonably well (and I've implemented lazy evaluation in other languages, etc.). But I've also traced some really annoying and hard to find bugs to unexpected (and sometimes never fully explained) consequences of laziness, so I'd like to find the best ways to avoid it when I don't really want it. If that best way turns out to make things run faster too then that'd be fantastic. -Lee -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to [email protected] Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
