klona

Related Links

• GitHub

Introduction

klona is a tiny (240B to 501B) and fast utility to "deep clone" Objects, Arrays, Dates, RegExps, and more!

Features

• Super tiny and performant
• Deep clone / recursive copies
• Safely handles complex data types: Array, Date, Map, Object, RegExp, Set, TypedArray, and more.

Unlike a "shallow copy" (eg, Object.assign), a "deep clone" recursively traverses a source input and copies its values — instead of references to its values — into a new instance of that input. The result is a structurally equivalent clone that operates independently of the original source and controls its own values.

Why "klona"? It's "clone" in Swedish.

Install

npm install --save klona

Modes

There are multiple "versions" of klona available, which allows you to bring only the functionality you need!

klona/json

Size (gzip): 240 bytes Availability: CommonJS, ES Module, UMD Ability: JSON data types

import { klona } from 'klona/json';

klona/lite

Size (gzip): 354 bytes Availability: CommonJS, ES Module, UMD Ability: extends klona/json with support for custom class, Date, and RegExp

import { klona } from 'klona/lite';

klona (default)

Size (gzip): 451 bytes Availability: CommonJS, ES Module, UMD Ability: extends klona/lite with support for Map, Set, DataView, ArrayBuffer, TypedArray

import { klona } from 'klona';

klona/full

Size (gzip): 501 bytes Availability: CommonJS, ES Module, UMD Ability: extends klona with support for Symbol properties and non-enumerable properties

import { klona } from 'klona/full';

Usage

import { klona } from 'klona';

const input = {
  foo: 1,
  bar: {
    baz: 2,
    bat: {
      hello: 'world'
    }
  }
};

const output = klona(input);

// exact copy of original
// assert.deepStrictEqual(input, output); // For assertion in Node.js environment

// applying deep updates...
output.bar.bat.hola = 'mundo';
output.bar.baz = 99;

// ...doesn't affect source!
console.log(JSON.stringify(input, null, 2));
// {
//   "foo": 1,
//   "bar": {
//     "baz": 2,
//     "bat": {
//       "hello": "world"
//     }
//   }
// }

API

klona(input)

Returns: typeof input

Returns a deep copy/clone of the input.