nullish-coalescing.js

let foo = '';

let a = (3 - 3) || "this is falsy";   // returns "this is falsy" - 3 - 3 = 0 which is falsy
let b = (3 - 3) ?? "this is nullish"; // returns 0 - 3 - 3 = 0 which is not null or undefined
let c = foo || "this is falsy";       // returns "this is falsy" - since '' is falsy
let d = foo ?? "this is nullish";     // returns '' - since '' is not null or undefined