On Aug 26, 12:40 pm, Tassilo Horn <tass...@member.fsf.org> wrote: > Paul Mooser <taron...@gmail.com> writes: > > Hi Paul, > > > If you search for "filter" and "StackOverflowError" in this group, you > > will find people discussing related issues. > > Thanks, I've found some explanation by Meikel Brandmeier who explains > the layering issue. But do we really have to live with that? > > I mean, replacing the filter/remove with a list comprehension solved the > issue for me. And it's easy to define filter in terms of for. > > --8<---------------cut here---------------start------------->8--- > user> (defn philter [pred coll] > (for [x coll :when (pred x)] x)) > #'user/philter > user> (filter even? (take 10 (iterate inc 0))) > (0 2 4 6 8) > user> (philter even? (take 10 (iterate inc 0))) > (0 2 4 6 8) > --8<---------------cut here---------------end--------------->8--- > > I've tried benchmarking filter vs. philter with seqs of different sizes, > and there seems to be no difference. So why not simply do it that way?
It would make no difference. philter is exactly as lazy as filter, and will have the same stacked-laziness problem. See http://stackoverflow.com/questions/2946764/recursive-function-causing-a-stack-overflow which in my opinion is a pretty clear presentation of the problem. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
