How to find an array in another array?

Question

These codes don't work:

const a = [[1, 1], [2, 2]]
console.log(a.includes([1, 1])); // --> false
console.log(a.indexOf([1, 1])); // --> -1

This work but I think its not optimized

console.log(a.map(x => x.toString()).includes([1, 1].toString()));
// --> true

Is there a simpler way ?

this might also help: https://stackoverflow.com/questions/7837456/how-to-compare-arrays-in-javascript (if `[1, 1]` are the same reference in memory, then you can find your result using the first two methods) — Nick Parsons, Aug 19 '19 at 10:26
Array is one kind of object, both the objects are referring to a different location from the addressing point of view. Compare each element one by one. — Sufiyan Ansari, Aug 19 '19 at 10:29

score 0 · Accepted Answer · answered Aug 19 '19 at 10:36

0

const a = [[1, 1], [2, 2]]
var index=a.findIndex(x=>{return JSON.stringify(x)===JSON.stringify([2, 2])})

console.log(`item index : ${index}`);

answered Aug 19 '19 at 10:36

Libin C Jacob

score -2 · Answer 2 · answered Aug 19 '19 at 10:26

-2

Assuming this:

var arr = ['a', 'b', 'b'];

you can invoke:

Array.isArray(arr);

will return true if the considered variable is an array, otherwise not.

Once you get it, you can apply it to the external array.

answered Aug 19 '19 at 10:26

Istorn

2 Answers2