Any clean way to avoid explicit recursion when creating nested loops?
I was discussing this on the clojure channel, and it seems as though avoiding explicit recursion is the idiomatic thing to do. Is there a better way to define a function that loops over an arbitrary number of sequences in a nested fashion, similar to the 'for' macro, without relying on recursion? This is the current approach, using recursion: (defn nested [ seqs] returns lazy 'for'-like nesting of a seq of seqs. (letfn [(nestrec [prefix [list deeper-lists]] (if deeper-lists (mapcat #(nestrec (conj prefix %) deeper-lists) list) (map #(conj prefix %) list)))] (nestrec [] seqs))) so (nested (range) [:a :b]) returns [[0 :a][0 :b] [1 :a] [1 :b] [2 :a] ... ] -- 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
Re: Any clean way to avoid explicit recursion when creating nested loops?
That's perfect, thanks! On Sep 30, 4:55 pm, Mark Engelberg mark.engelb...@gmail.com wrote: clojure.contrib.cartesian-product does what your nested function does, but more efficiently, using iteration rather than recursion. -- 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
