js copay of array [...array] code example

Example 1: javascript duplicate an array

let arr =["a","b","c"];
// ES6 way
const duplicate = [...arr];

// older method
const duplicate = Array.from(arr);

Example 2: how to copy one array to another in javascript

// 1) Array of literal-values (boolean, number, string) 
const type1 = [true, 1, "true"];

// 2) Array of literal-structures (array, object)
const type2 = [[], {}];

// 3) Array of prototype-objects (function)
const type3 = [function () {}, function () {}];