JSFiddle - React, Tailwind, and code Playground

JavaScript

var accumulator =[];

function mapForEach(array, transformation) {
    array.forEach(transformation);
    return accumulator;
}

function transformation(person, index, array) {
    var name = person.name;
    accumulator.push(name);
}

var array = [
    {
        name: 'aa',
        age: 34
    },
    {
        name: 'bb',
        age: 54
    },
    {
        name: 'cc',
        age: 24
    }
];

var output = mapForEach(array, transformation);
console.log(output);