what's the actual use case where you want this? it seems pretty weird just on it's own. it may in practice be more clever than other solutions, but that's not clear yet. if you just want a unique symbol there's (gensym)
regarding vectors, I found this a helpful read a while back, it's a few years old, but I think it's still accurate, and may help you get a picture of what's under the hood. http://blog.higher-order.net/2009/02/01/understanding-clojures-persistentvector-implementation/ Kevin On Sep 23, 12:09 am, F Lengyel <florian.leng...@gmail.com> wrote: > On Sep 23, 1:39 am, Nathan Sorenson <n...@sfu.ca> wrote: > > > Just to clarify, you want to conj a vector to itself? i.e. [1 2 3 4] --> [1 > > 2 3 4 [1 2 3 4]] I'm curious what the application of this is. > > > Regarding the overhead of conj-ing to a vector: Clojure's data structures > > make use of structural sharing so conjoining an element to the end of a > > vector won't require any copying of entire vectors. It's a cheap, > > constant(ish) time operation. > > Good: (conj v v) is O(1) in time and space, and appends an element > distinct from the preceding elements (if any). I meant to add that > querying > the vector is not allowed. The reason is to use reduce in situations > where > some data structure is created based on a previous and current > element. If the last element is guaranteed to be different from those > preceding it, then an edge case is eliminated (or rather, encoded into > the sequence at minimal cost). -- 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
