How Do I Create a True Copy of a JavaScript Array?

Cloning Arrays in JavaScript

In JavaScript, copying an array by assignment creates a reference to the original array rather than an independent copy. This can lead to unexpected behavior, as demonstrated in the following code snippet:

var arr1 = ['a', 'b', 'c'];
var arr2 = arr1;
arr2.push('d'); // Now, arr1 = ['a', 'b', 'c', 'd']

To create an independent copy of an array, use the slice() method:

let oldArray = [1, 2, 3, 4, 5];
let newArray = oldArray.slice();
console.log({newArray}); // [1, 2, 3, 4, 5]

The slice() method returns a shallow copy of the original array, creating a new array with the same elements but no direct reference to the original array. This ensures that changes made to the new array do not affect the original array.

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