remove function does index instead of value code example

Example 1: js remove if

ar = [1, 2, 3, 4];
ar = ar.filter(item => !(item > 3));
console.log(ar) // [1, 2, 3]

Example 2: pop up element from specific index in array

let items = ['a', 'b', 'c', 'd'];
let index = items.indexOf('a')
let numberOfElementToRemove = 1;
if (index !== -1) { items.splice(index,numberOfElementToRemove)}