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Discussion on: 2 Uses of concat method when working with arrays in JavaScript

lukeshiru profile image

Worth mentioning than for flattening, you can just use Array.prototype.flat (mdn):

[[1, 2, 3], [4, 5, 6]].flat(); // [1, 2, 3, 4, 5, 6]
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Another "flat related" method is Array.prototype.flatMap (mdn), which you can use like this:

[1, 2, 3].flatMap(value => [value, value *2]); // [1, 2, 2, 4, 3, 6]
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Generally is better to use any of these to flatten instead of concat.


kritikapattalam profile image
Kritika Pattalam Bharathkumar Author

100% agree with you. Using Array.prototyoe.flat is the most efficient way, but the post was more about what concat is possible of doing.
Thanks for adding this, its helpful for others reading that concat is not the only way to flatten arrays.