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performant-array-to-tree
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Converts an array of items with ids and parent ids to a nested tree in a performant `O(n)` way. Runs in browsers and node.
Converts an array of items with ids and parent ids to a nested tree in a performant way (time complexity O(n)
). Runs in browsers and node.
Other packages have stricter assumptions or are not as performant, as they often use nested loops or recursion. For example:
o-unflatten requires the input to be ordered such that parent nodes always come before their children.
un-flatten-tree uses 2 nested loops (time complexity O(n^2)
).
This implementation does not require any order of items in the input array and focuses on runtime performance. It is the fastest amongst 4 different packages, you can find the benchmarks here. It uses an index and a single loop (time complexity O(n)
). It was inspired by this discussion on StackOverflow.
yarn add performant-array-to-tree
or if using npm
npm install --save performant-array-to-tree
const tree = arrayToTree([
{ id: '4', parentId: null, custom: 'abc' },
{ id: '31', parentId: '4', custom: '12' },
{ id: '1941', parentId: '418', custom: 'de' },
{ id: '1', parentId: '418', custom: 'ZZZz' },
{ id: '418', parentId: null, custom: 'ü'},
])
Which results in the following array:
[
{ data: { id: '4', parentId: null, custom: 'abc' }, children: [
{ data: { id: '31', parentId: '4', custom: '12' }, children: [] },
] },
{ data: { id: '418', parentId: null, custom: 'ü'}, children: [
{ data: { id: '1941', parentId: '418', custom: 'de' }, children: [] },
{ data: { id: '1', parentId: '418', custom: 'ZZZz' }, children: [] },
] },
]
You can provide a second argument to arrayToTree with configuration options. Right now, you can set the following:
id
: key of the id field of the item. Default: "id"
parentId
: key of the parent's id field of the item. Default: "parentId"
childrenField
: key which will contain all child nodes of the parent node. Default: "children"
dataField
: key which will contain all properties/data of the original items. Set to null if you don't want a container. Default: "data"
Example:
const tree = arrayToTree([
{ num: '4', ref: null, custom: 'abc' },
{ num: '31', ref: '4', custom: '12' },
{ num: '1941', ref: '418', custom: 'de' },
{ num: '1', ref: '418', custom: 'ZZZz' },
{ num: '418', ref: null, custom: 'ü'},
], { id: 'num', parentId: 'ref', childrenField: 'nodes' })
Which produces:
[
{ data: { num: '4', ref: null, custom: 'abc' }, nodes: [
{ data: { num: '31', ref: '4', custom: '12' }, nodes: [] },
] },
{ data: { num: '418', ref: null, custom: 'ü'}, nodes: [
{ data: { num: '1941', ref: '418', custom: 'de' }, nodes: [] },
{ data: { num: '1', ref: '418', custom: 'ZZZz' }, nodes: [] },
] },
]
Example with no data field:
const tree = arrayToTree([
{ id: '4', parentId: null, custom: 'abc' },
{ id: '31', parentId: '4', custom: '12' },
{ id: '1941', parentId: '418', custom: 'de' },
{ id: '1', parentId: '418', custom: 'ZZZz' },
{ id: '418', parentId: null, custom: 'ü'},
], { dataField: null })
Which produces:
[
{ id: '4', parentId: null, custom: 'abc', children: [
{ id: '31', parentId: '4', custom: '12', children: [] },
] },
{ id: '418', parentId: null, custom: 'ü', children: [
{ id: '1941', parentId: '418', custom: 'de', children: [] },
{ id: '1', parentId: '418', custom: 'ZZZz', children: [] },
] },
]
This project includes types, just import the module as usual:
import { arrayToTree } from 'performant-array-to-tree'
const tree = arrayToTree(array)
FAQs
Converts an array of items with ids and parent ids to a nested tree in a performant `O(n)` way. Runs in browsers and node.
The npm package performant-array-to-tree receives a total of 23,079 weekly downloads. As such, performant-array-to-tree popularity was classified as popular.
We found that performant-array-to-tree demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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