Shallow array equals in javascript

June 17, 2023

Are there any improvements that can be made on the following to check the equality of two arrays in javascript?

"use strict"
function main(arr1, arr2) {
    if (arr1.length !== arr2.length) {
        return false;
    }
    for (let i = 0; i < arr1.length; i++) {
        if (arr1[i] !== arr2[i]) {
            return false
        }
    }
    return true;
}
const tests = [
  [[1,2],[1,2]],
  [[1],[1,2]],
  [[1,2],[1]],
  [[1,2],[3,4]],
  [[],[]]
]
for (const [arr1, arr2] of tests) {
  let res = main(arr1, arr2);
  console.log(arr1, arr2, res);
}

>Solution :

Not sure this is an improvement, but you could make it shorter:

"use strict"

function main(arr1, arr2) {
    return (
      arr1.length === arr2.length
      && arr1.every((v, i) => arr2[i] === v)
    );
}

const tests = [
  [[1,2],[1,2]],
  [[1],[1,2]],
  [[1,2],[1]],
  [[1,2],[3,4]],
  [[],[]]
]
for (const [arr1, arr2] of tests) {
  let res = main(arr1, arr2);
  console.log(arr1, arr2, res);
}