On Thursday, 17 April 2014 04:28:02 UTC+8, John Mastro wrote: > > > I assume that there's a good reason that iterate returns a Cons > > instead of a LazySeq. > > IIUC, this particular case arises because iterate's body is implemented > as > > (cons x (lazy-seq (iterate f (f x)))) > > rather than > > (lazy-seq (cons x (iterate f (f x)))) > > Can anyone comment on whether there's a reason to prefer one over the > other? >
The difference is that the former is slightly less lazy - the Cons cell containing x is constructed immediately rather than being deferred as part of the lazy seq. This probably performs slightly better in some circumstances, and since you already have x as a value it probably makes sense to do this eagerly since no arbitrary computation is being done (f doesn't need to be called yet in either case). -- 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.
