@egjs/children-differ

What is @egjs/children-differ?

@egjs/children-differ is an npm package designed to efficiently detect changes in a list of children elements. It is particularly useful for applications where you need to track and respond to changes in a dynamic list of elements, such as in virtualized lists or complex UI components.

What are @egjs/children-differ's main functionalities?

Detecting Added and Removed Children

This feature allows you to detect which children have been added or removed between two states of a list. The code sample demonstrates how to use the `update` method to compare two lists and get the differences.

const ChildrenDiffer = require('@egjs/children-differ');

const differ = new ChildrenDiffer();
const prevList = ['a', 'b', 'c'];
const nextList = ['a', 'c', 'd'];

const result = differ.update(prevList, nextList);
console.log(result); // { added: [{ index: 2, value: 'd' }], removed: [{ index: 1, value: 'b' }], maintained: [{ index: 0, value: 'a' }, { index: 1, value: 'c' }] }

Detecting Moved Children

This feature allows you to detect which children have been moved between two states of a list. The code sample demonstrates how to use the `update` method to compare two lists and get the moved elements.

const ChildrenDiffer = require('@egjs/children-differ');

const differ = new ChildrenDiffer();
const prevList = ['a', 'b', 'c'];
const nextList = ['c', 'a', 'b'];

const result = differ.update(prevList, nextList);
console.log(result); // { added: [], removed: [], maintained: [{ index: 0, value: 'c' }, { index: 1, value: 'a' }, { index: 2, value: 'b' }], moved: [{ from: 2, to: 0, value: 'c' }, { from: 0, to: 1, value: 'a' }, { from: 1, to: 2, value: 'b' }] }

Other packages similar to @egjs/children-differ

react-diff

react-diff is a package that provides utilities for diffing React elements. It is similar to @egjs/children-differ in that it helps detect changes in a list of elements, but it is specifically designed for React components.

diff

diff is a general-purpose text diffing library that can be used to compare strings, arrays, and objects. While it is not specifically designed for detecting changes in children elements, it provides similar functionality for comparing lists and detecting differences.

immutability-helper

immutability-helper is a package that provides utilities for working with immutable data structures. It includes functions for updating lists and detecting changes, similar to @egjs/children-differ, but with a focus on immutability.

README

@egjs/children-differ

➕➖🔄 A module that checks diff when child elements are added, removed, or changed.

⚙️ Installation

$ npm i @egjs/children-differ

<script src="//naver.github.io/egjs-children-differ/release/latest/dist/children-differ.pkgd.min.js"></script>

📖 Documentation

• See Documentation page.
• Introducing ListDiffer to track changes in data and track changes(한국어)
• How to Make Cross Framework Component(한국어)

📦 Packages

Package	Version	Description
@egjs/react-children-differ		React port of @egjs/children-differ
@egjs/ngx-children-differ		Angular port of @egjs/children-differ
@egjs/vue-children-differ		Vue.js port of @egjs/children-differ

🏃How to use

Usage is similar to @egjs/list-differ.

checks diff

<div id="container">
    <div>0</div>
    <div>1</div>
    <div>2</div>
    <div>3</div>
    <div>4</div>
    <div>5</div>
    <div>6</div>
</div>
<script>

import ChildrenDiffer from "@egjs/children-differ";

// Value is key
const differ = new ChildrenDiffer(conatiner.children);


container.removeChild(container.children[5]);
container.removeChild(container.children[2]);

const result = differ.update(container.children);
// [2, 5]
console.log(result.removed);
</script>

🙌 Contributing

See CONTRIBUTING.md.

📝 Feedback

Please file an Issue.

📜 License

@egjs/list-differ is released under the MIT license.

Copyright (c) 2019-present NAVER Corp.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.