Christophe Grand a écrit : > Timothy Pratley a écrit : > >> I want to grow a tree programmatically so have been trying zippers: >> >> (defn insert-parent [loc n] >> (clojure.zip/replace loc (clojure.zip/make-node >> loc n loc))) >> (println (clojure.zip/root (insert-parent (clojure.zip/seq-zip (list >> 1)) 2))) >> (println (clojure.zip/root (clojure.zip/append-child >> (clojure.zip/seq-zip (list 1)) 2))) >> >> [(1) nil] >> (1 2) >> >> My 'insert-parent' function does not work, I was trying to get (2 1) - >> any tips? >> >> > > It's clojure.zip/insert-child you are looking for: > > clojure.contrib.struct-ed=> (clojure.zip/root (clojure.zip/insert-child > (clojure.zip/seq-zip (list 1)) 2)) > (2 1) > > Christophe >
My take on your followup question (asked on #clojure): If you want to add a parent you have to know how to make a new node with a single child. Since you are using seq-zip, it's easy: you simply use 'list ((list x) yields indeed a node with one child: x)! user=> (-> '(1) clojure.zip/seq-zip (clojure.zip/edit list) clojure.zip/root) ((1)) Then you can easily add 2: user=> (-> '(1) clojure.zip/seq-zip (clojure.zip/edit list) (clojure.zip/insert-child 2) clojure.zip/root) (2 (1)) or in a single step: user=> (-> '(1) clojure.zip/seq-zip (clojure.zip/edit #(list 2 %)) clojure.zip/root) (2 (1)) Christophe --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
