I'm trying to refactor JS code into functions. I'm comparing two arrays and return a new array with any items only found in one of the two given arrays, but not both.
The code below works, but obviously it's not DRY principal.
function diffArray(arr1, arr2) {
let newArr = []
for(let el2 of arr2) {
if(!arr1.includes(el2)) {
newArr.push(el2)
}
}
for(let el1 of arr1) {
if(!arr2.includes(el1)) {
newArr.push(el1)
}
}
return newArr;
}
I want to turn the loop block into a function and below is what i came up with. However, it returns an empty array. What's the issue here?
let newArr = []
function singleEl(arrA, arrB) {
for(let el of arrA) {
if(!arrB.includes(el)) {
newArr.push(el)
}
return newArr
}}
function diffArray(arr1, arr2) {
singleEl(arr2, arr1)
singleEl(arr1, arr2)
return newArr;
}
diffArray([1, "calf", 3, "piglet"], [1, "calf", 3, 4])
Your problem is return newArr inside the loop.
function singleEl(arrA, arrB) {
let newArr = [];
for (let el of arrA) {
if (!arrB.includes(el))
newArr.push(el);
}
return newArr;
}
function diffArray(arr1, arr2) {
let result = [];
result = [...singleEl(arr1, arr2), ...singleEl(arr2, arr1)];
return result;
}
console.log(diffArray([1, 2], [1, 5, 6]));
console.log(diffArray([1, "calf", 3, "piglet"], [1, "calf", 3, 4]));