find first from each letter js code example

Example 1: get first object key javascript

var example = {
    foo1: { /* stuff1 */},
    foo2: { /* stuff2 */},
    foo3: { /* stuff3 */}
};

let [first] = Object.keys(example)

console.log(first)

Example 2: js get words first letter

var str = "Java Script Object Notation";
var matches = str.match(/\b(\w)/g); // ['J','S','O','N']
var acronym = matches.join(''); // JSON

console.log(acronym)