On Apr 15, 2009, at 11:30 PM, bOR_ wrote:
> > Hi all, > > some functions (like map, or update-in) expect a function to be > applied on a value. In the case where the update I want is merely a > constant, is there a short way to write it? > > (map (fn [n] :new) (list :old1 :old2 :old3)) works > > (map :new (list :old1 :old2 :old3)) unfortunately doesn't work in the > way I would hope (gives nil nil nil) > There are a number of possible answers here depending on what you're trying to do. The one that corresponds literally to your approach is this: (map (constantly :new) (list :old1 :old2 :old3)) 'constantly' creates a function which simply ignores its arguments and returns the value provided. But if all you are really doing is creating a sequence of a given length containing a constant element, then this is more straightforward: (repeat (count (list :old1 :old2 :old3)) :new) Aloha, David Sletten --~--~---------~--~----~------------~-------~--~----~ 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 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 -~----------~----~----~----~------~----~------~--~---
