I do not think we will extend into to support array sources. If your source is a vector, then vector seqs are actually really fast and into-array is probably not as bad as you think, however it won't apply the xf.
into is just doing transduce internally though and transducers are agnostic to how their outputs are handled. You could replace the reducing function in that transduce with something that incremented the index and set the next value like: (defn into-long-array [xf v] (let [arr (long-array (count v)) index (volatile! 0) conj-arr (fn [a item] (aset a @index item) (vswap! index inc) a)] (transduce xf (completing conj-arr) arr v))) (into-long-array (map inc) [0 1 2 3]) ;; returns long[] of [1 2 3 4] That could be generalized probably to take the array and the index to start adding elements, although given expanding transducers like mapcat, this would fail so you need some a priori knowledge about that. On Wednesday, May 11, 2016 at 4:31:02 AM UTC-5, Laszlo wrote: > > Hi, > > > The other day I was trying to do an > > (into (long-array 0) xform some-vec) > > which doesn't work, then I realized there is *into-array* for that, > however, it turns everything into a *seq* first. > > Is there any plans for extending *into* to hand primitive array, or > rewriting *into-array* to do away with the extra allocation? > > Thanks, > > Laszlo > -- 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 --- 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 clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.