如何在结构中移动元素，可能使用拉链？ [英] How to move an element within a structure, possibly with zippers?

问题描述

我有这种结构：

  [{a{b1c2} 
children[{a{b3c4}children[]}]} 
 {a{b5c } 
 {a{b7c8} 
children[{a{b9c10}children[]} {a {b10c10}children[]}]}] 
  

I试图写一个算法来移动和向量内的元素。例如在最后一个元素中，它有 children 向量与：

  children[{a{b9c10}children[]} {a{b10c10}children[]}] 
  

我的函数应该搜索一个特定的嵌套映射 - 让我们说，找到它的值 10 为其 b 属性。我会找到 {a{b10c10}children[]} 。一旦我找到它，我需要改变它的位置与向量。让我们假设 children 将成为：

  a{b10c10}children[]} {a{b9c10}children[]}] 
  
 
 
 
使用Zipper，我可以遍历和定位嵌套地图，但不知道如何在向量中移动它。
 
 
 
以下是我的拉链的创建方式：
 （z / child）＃（get％children）（fn [_ c] c）data-structure）
  
 
 
解决方案
这将做我想要的：
 （defn update-tree [editable ？edit loc] 
（loop [loc loc] 
（if（z / end？loc）
（z / root loc）
 loc））
（recur（ - > loc z / up（z / edit edit）z / up z / next））
（recur（z / next loc））））） $ b  
但它只适用于这个精确的结构。嵌套更多元素会破坏算法。
 
I have this structure:
 [{"a" {"b" 1 "c" 2} 
   "children" [{"a" {"b" 3 "c" 4} "children" []}]}
  {"a" {"b" 5 "c" 6} "children" []}
  {"a" {"b" 7 "c" 8}
    "children" [{"a" {"b" 9 "c" 10} "children" []} {"a" {"b" 10 "c" 10} "children" []}]}]
I'm trying to write an algorithm to move and element within a vector. For example in the last element, it has children vector with:
"children" [{"a" {"b" 9 "c" 10} "children" []} {"a" {"b" 10 "c" 10} "children" []}]
My function is supposed to search for a specific nested map - let's say, find the map where it is the value 10 for its b property. I will locate {"a" {"b" 10 "c" 10} "children" []}. Once I found it, I need to change its location with the vector. Let's assume, that children will become:
 "children" [{"a" {"b" 10 "c" 10} "children" []} {"a" {"b" 9 "c" 10} "children" []}]
With Zipper, I was able to traverse and locate the nested map but not sure how to move it within the vector.

Here is how my zipper is created:
  (z/zipper #(contains? % "children") #(get % "children")  (fn [_ c] c) data-structure)

解决方案
This will do what I want:
(defn update-tree [editable? edit loc]
  (loop [loc loc]
    (if (z/end? loc)
    (z/root loc)
    (if (editable? (z/node loc))
      (recur (-> loc z/up (z/edit edit) z/up z/next))
      (recur (z/next loc))))))
But it is only working for this exact structure. Nesting more elements is breaking the algorithm.

                        
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