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Tutorial
The JavaScript language
Data types
Arrays

Is array copied?

importance: 3

What is this code going to show?

let fruits = ["Apples", "Pear", "Orange"];

// push a new value into the "copy"
let shoppingCart = fruits;
shoppingCart.push("Banana");

// what's in fruits?
alert( fruits.length ); // ?

The result is 4:

let fruits = ["Apples", "Pear", "Orange"];

let shoppingCart = fruits;

shoppingCart.push("Banana");

alert( fruits.length ); // 4

That’s because arrays are objects. So both shoppingCart and fruits are the references to the same array.

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