On Mon, Nov 19, 2012 at 6:24 PM, Andy Fingerhut <andy.finger...@gmail.com> wrote: > Clojure's loop/recur only implements tail recursion, not general tail-call > optimization. tail recursion is far more commonly used in languages that > have it than the general tail-call optimization to arbitrary functions.
Can you explain this? I'm assuming that "having tail recursion" here means not "you can call yourself in tail position" but "calls to yourself in tail position don't grow the stack". But I don't really follow the second sentence, which seems to have two possible continuations: (a) tail recursion is far more commonly used in languages that have it than the general tail-call optimization to arbitrary functions ... is used in languages that have tail recursion. (b) tail recursion is far more commonly used in languages that have it than the general tail-call optimization to arbitrary functions ... is used in languages that have *it* (i.e. general TCO). But in (a), general tail-call optimization to arbitrary functions couldn't be used very much in those languages; they don't have it. And in (b), general TCO subsumes the optimization of tail recursion and comes into play whenever a procedure is called from tail position, so it would seem to be used pervasively in languages that have general TCO. -- Ben Wolfson "Human kind has used its intelligence to vary the flavour of drinks, which may be sweet, aromatic, fermented or spirit-based. ... Family and social life also offer numerous other occasions to consume drinks for pleasure." [Larousse, "Drink" entry] -- 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
