Merge Arrays in one with ES6 Array spread

gistfile1.txt

const arr1 = [1,2,3]
const arr2 = [4,5,6]
const arr3 = [...arr1, ...arr2] //arr3 ==> [1,2,3,4,5,6]

This is so strange.. I rather use arr3= arr1.concat(arr2)

This way has a lot of performance issues

_travelDevs

Thanks.. Its working. You make my day

I'm getting an error jQuery is not defined?

this es6 solution is also pretty cool
const concat = (...args) => args.flat();
concat([1, 2, 3], [4, 5], [6, 7]); //➞ [1, 2, 3, 4, 5, 6, 7]

I'm getting an error jQuery is not defined?

You need to add jQuery external link in script tag

arr3 = [...arr1, ...arr2]; will fail if any of them are null.

const arr = [[1,2,3], [4,5,6]]
const merged = arr.reduce((a, b) => { a.splice(0, 0, b); return a; }, [])