- Python – User Input
`input()` always hands you a string, which is where most beginner bugs start. Validating and converting it, looping until the answer is usable, hidden input for passwords, and `argparse` when the input is command-line arguments instead.
- Frontend Dev – The JavaScript and TypeScript You Actually Need
The subset of the language that matters in a component app, which is not the subset a beginner course teaches. Immutable updates, the async model that makes a spinner possible, modules, and the handful of TypeScript ideas that catch real bugs — typing the API response, discriminated unions for loading state, and why `any` is a loss.
- Java 25 Flexible Constructor Bodies
Until Java 25, super() or this() had to be the very first statement in a constructor. Nothing could run before it. Flexible constructor bodies lift that restriction, which means you can finally validate an argument before handing it to the superclass. The restriction That rule existed for a good…
- iOS – Sheets, Modals and Alerts
sheet(isPresented:) versus sheet(item:), and why the second one resets a form for free. Detents, drag indicators, alerts and confirmation dialogs, and the boolean-flag mistake that makes a tap look like it was dropped — with the one enum that makes it unrepresentable.
- Spring Study Guide – AOP
Cross-cutting concerns, and the vocabulary you are expected to use precisely: join point, pointcut, advice, aspect, weaving. The five advice types and when each runs, the pointcut expressions worth memorising, what JoinPoint and ProceedingJoinPoint give you, the self-invocation limitation that catches everyone — and the Boot 4 starter rename that breaks every old pom.