You know async/await is syntactic sugar over Promises. But do you understand the microtask queue? Do you know why this code logs the way it does?
An “interesting review” of YDKJ often says more about the than the book’s quality. If they were humbled but grateful, they’ll praise it. If they felt talked down to, they’ll pan it. Rarely is the review neutral.
If you ask "What is the difference between Object.create(null) and {} ?" and you can't answer, read this book.
The word changes the entire context. It transforms a statement of inadequacy into a statement of potential. It acknowledges that learning is a spectrum. You might know how to write a function, but do you know how lexical scope works? You might know how to use Promise.then() , but do you understand the microtask queue? you don 39-t know js yet
If you don't understand why typeof behaves differently for undeclared variables vs. TDZ variables, you don't know JS yet.
// TDZ starts console.log(typeof notYetDeclared); // Outputs "undefined" (safely) console.log(typeof laterLet); // Throws ReferenceError! let laterLet = 'hello';
Because of this abstraction, most developers suffer from . They don't know what they don't know. You know async/await is syntactic sugar over Promises
Want to dig into which one you think the reviewer meant? Or how YDKJ holds up in 2025?
Because the moment you think you know everything about JavaScript is the exact moment you become obsolete.
For example, ask a random React developer how JavaScript handles Coercion . They will likely recite the meme: "Don't use == , always use === ." But ask them why —ask them about the ToPrimitive abstract operation, or how [] == ![] evaluates to true —and the confidence vanishes. An “interesting review” of YDKJ often says more
Forget ES6 class sugar for a moment. You need to understand . Objects delegate to other objects. Classes are a lie (syntactic sugar over prototypes).
: Explores prototypes, the this keyword, and how "classes" actually work in JS (forthcoming/in-progress in the 2nd edition).