JavaScript and TypeScript Foundations

19:30 – 21:30

JavaScript: what it is, why it behaves that way, and how it runs

engines, runtimes and where JavaScript runs, types, values and the misconceptions, tested live, the DOM, events and event delegation, why textContent is safe and innerHTML is not

Takeaway ShopScope Lite's first page: sixteen product cards built from data, sale prices, stock badges and a wishlist counter, plus a playground that tests eleven JavaScript myths.

19:30 – 21:30

Modern JavaScript (ES6+): search, filter and sort a catalogue

let, const, destructuring, spread and rest, optional chaining, and ?? versus ||, map, filter, reduce, Set and Map, modules, and one state object driving the view

Takeaway A catalogue you can search as you type, filter by category with live counts and sort five ways, with a live stats panel and a wishlist that survives a reload.

19:30 – 21:30

Functions, closures, this and immutability: one cart built twice

closures, stale state and why React state is a snapshot, debounce and memoize, written by hand, the four rules of this, and classes with private fields, reference equality and immutable updates

Takeaway A debounced search and a working cart, built as a React-style closure store and as an Angular-style class service, with a live check that every change returns a new reference.

19:30 – 21:30

Async JavaScript and the event loop: a catalogue that cancels and retries

the event loop, tasks and microtasks, promises, async and await, and fetch done properly, race conditions ended with AbortController, retry with backoff, and Observables for Angular

Takeaway A live catalogue from the DummyJSON API that loads in parallel, cancels stale searches, retries a failing API with exponential backoff and logs every request.

19:30 – 21:30

TypeScript for React and Angular: the live catalogue in strict mode

inference, unions, narrowing and type guards, discriminated unions and exhaustive checks, generics: fetchJson<T> and createStore<T>, strict mode, utility types, and unknown versus any

Takeaway The same live catalogue in strict TypeScript with zero any, one RequestState type driving the screen, and the same types shown in a React hook and an Angular service.