Convert the array with nested arrays to the new array without nested arrays (JavaScript)

Question

I have the array "arrs" with nested arrays like below:

let arrs = ["Apple", ["Peach", "Grape"], [["Pear", "Kiwi"], ["Lemon"]]];

Now, I want to convert the array "arrs" to the new array "newArr" without nested arrays like below:

let newArr = [ "Apple", "Peach", "Grape", "Pear", "Kiwi", "Lemon" ];

I created the code to convert "arrs" to "newArr" without nested arrays:

let newArr = [arrs[0], arrs[1][0], arrs[1][1], arrs[2][0][0], arrs[2][0][1], arrs[2][1][0]];

console.log(newArr); // [ "Apple", "Peach", "Grape", "Pear", "Kiwi", "Lemon" ]

This is the full runnable code:

let arrs = ["Apple", ["Peach", "Grape"], [["Pear", "Kiwi"], ["Lemon"]]];

let newArr = [arrs[0], arrs[1][0], arrs[1][1], arrs[2][0][0], arrs[2][0][1], arrs[2][1][0]];

console.log(newArr); // [ "Apple", "Peach", "Grape", "Pear", "Kiwi", "Lemon" ]

However, I want to make this code simpler, cooler or clever. Are there any ways to do this?

let newArr = [arrs[0], arrs[1][0], arrs[1][1], arrs[2][0][0], arrs[2][0][1], arrs[2][1][0]];

console.log(newArr); // [ "Apple", "Peach", "Grape", "Pear", "Kiwi", "Lemon" ]

Super Kai - Kazuya Ito · Answer 1 · 2021-12-09T21:30:23.147

1

You can use "flat()" with "2":

let arrs = ["Apple", ["Peach", "Grape"], [["Pear", "Kiwi"], ["Lemon"]]];

let newArr = arrs.flat(2);

console.log(newArr); // [ "Apple", "Peach", "Grape", "Pear", "Kiwi", "Lemon" ]

In addition, you can use "flat()" with "Infinity" for any depth of nested array.

let arrs = ["Apple", ["Peach", "Grape"], [["Pear", "Kiwi"], ["Lemon"]]];

let newArr = arrs.flat(Infinity);

console.log(newArr); // [ "Apple", "Peach", "Grape", "Pear", "Kiwi", "Lemon" ]

edited Dec 09 '21 at 21:30

answered Dec 08 '21 at 12:59

Super Kai - Kazuya Ito

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Let's hope non of the strings in the array contain a comma. – Ivar Dec 08 '21 at 13:01
Very nice and uncommon way! – A1exandr Belan Dec 08 '21 at 13:23
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@Ivar, you right my bad – A1exandr Belan Dec 08 '21 at 13:28
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@Ivar, you right. If string contain a comma, my way with join() and split() don't work. Thanks for reminding me. – Super Kai - Kazuya Ito Dec 08 '21 at 13:59
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`["Apple", ["Peach", "Grape"], [["Pear", "Kiwi"], ["Lemon"]]].toString().split(',')` - also works – A1exandr Belan Dec 08 '21 at 17:17

Convert the array with nested arrays to the new array without nested arrays (JavaScript)

1 Answers1