node js function notation and syntactic sugar

gistfile1.txt

// from https://medium.com/@chineketobenna/lambda-expressions-vs-anonymous-functions-in-javascript-3aa760c958ae

function traverseArray(arr, func) {
    let result = '';
    for (const value of arr) {
        result += func(value) + ' ';
    }
    console.log(result);
}

const arr = [1, 2, 3, 4, 5];
const doubler = value => value * 2;

////alternatively, can be written verbosely as

// const doubler = (value) => {
//    return value * 2;
//}

// or link this:
// const doubler = function(value) {
//    return value * 2
//}

traverseArray(arr, doubler);      
//result: 2 4 6 8 10