Hi Dave, I don't know if there is the one true way of representing a tree as a vector, but clojure.zip allows you to zip over pretty much any structure you like, as long as you provide the right functions. The zipper function is a bit like an informal protocol in that way.
The built-in vector-zip treats all vectors as branch nodes, but these branch nodes don't have any "node value" of their own, as you would like them to have in your example. On Mon, Oct 15, 2012 at 01:20:13PM -0700, Dave Kincaid wrote: > <https://lh5.googleusercontent.com/-mq1roiqfqw4/UHxvMDQUIfI/AAAAAAAAA_o/mNA9pAkOEIs/s1600/tree.png> > my first intuition was a vector like this [:A [:B [:D :E]] [:C [:F :G]]] but > that didn't work. Then I thought of something like this: [[:B [:D :E]] :A > [:C [:F :G]]]. It seems like that gets me a little bit closer since now the > zipper at least gets that :A has two children. Here is a primitive example of how you might construct the tree you want with a vector notation. The first element in the vector is treated as the "node value", the rest as the children (this use of a vector is similar to how the hiccup library uses vectors, for example). (ns foo (:require [clojure.zip :as z] [clojure.string :as string])) (defn print-tree [loc] (when-not (z/end? loc) (do (println (str (string/join "" (repeat (count (z/path loc)) " ")) (if (z/branch? loc) (first (z/node loc)) (z/node loc)))) (recur (z/next loc))))) (defn my-make-node [n children] (cons (first n) children)) (defn my-zipper [v] (z/zipper coll? next my-make-node v)) (defn show-tree [] (print-tree (my-zipper [:A [:B :D :E] [:C :F :G]]))) Regards, Caspar -- 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
