Example JavaScript Map Function

map1.js

// INPUT
let numbers = [1, 2, 3, 4];
let results = [];

// MULTIPLY EACH ARRAY ITEM BY 2
function multiplyBy2(currentValue, index, arr) {
  return currentValue*2;
}

results = numbers.map(multiplyBy2);

// OUTPUT
// [2, 4, 6, 8]