I would use reductions(i.e. Haskell's scanl) given my understanding that clojure sequence is just as lazy as Haskell.
(rest (map first (reductions (fn [ [v a b] x ] (if (= a x) [b nil b] [x a b])) [nil 2 3] '(1 1 2 2 3 4)))) I use nil here as 'something that would not appear in the list', I am sure there are better marker if 'nil' is a valid value. If there is a foldr in clojure, it is also possible to short circuit the rest of comparison once the first is found. The other possibility is using 'unfold', I am not quite familiar with clojure's sequence functions. There may be one already, using some other names. -- 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
