Is there any difference between js concat function and spread operator merging/inserting?

Question

I am wondering if there is any difference between these two methods to push to array in javascript knowing that they both will create new array.

const arr0 = [obj1, obj2, obj3];
const arr1 = arr0.concat(obj4);    // method 1
const arr2 = [...arr0, obj4];      // method 2

@CertainPerformance is there any reference i can check ? Thanks — Elnoor, Feb 13 '20 at 08:18

score 1 · Answer 1 · answered Feb 13 '20 at 08:22

1

a=[1] a.concat([2,3]) will give [1,2,3] whereas [...a,[2,3]] gives [1,[2,3]]. For more info checkout this answer (spread operator vs array.concat())

answered Feb 13 '20 at 08:22

Mohit Singh

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Is there any difference between js concat function and spread operator merging/inserting?

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