Category: JavaScript

80 questions in JavaScript.

What are private class fields in JavaScript

January 18, 2026 · JavaScript

Learn how private class fields with hash prefixes enforce true encapsulation in JavaScript classes without closures or WeakMaps.

January 12, 2026 · JavaScript

Understand the nullish coalescing operator (??) for providing defaults only when values are null or undefined.

January 05, 2026 · JavaScript

Learn how optional chaining (?.) safely accesses nested properties without writing verbose null checks.

December 30, 2025 · JavaScript

Learn how WeakMap and WeakSet allow private data and deduplication without preventing garbage collection of their object keys.

December 24, 2025 · JavaScript

Master JavaScript generators for lazy evaluation, cooperative multitasking, and creating clean custom iterators with yield.

December 17, 2025 · JavaScript

Learn the iterable protocol in JavaScript, how to create custom iterators, and how for...of loops work under the hood.

December 11, 2025 · JavaScript

Understand JavaScript Symbols, unique primitive values that prevent property name collisions and enable meta-programming patterns.

December 05, 2025 · JavaScript

Explore template literals for interpolation and tagged templates for custom string processing in JavaScript.

November 28, 2025 · JavaScript

Learn how to organize code with ES6 modules using import and export, including named, default, and namespace exports.

November 22, 2025 · JavaScript

Learn how Object.freeze and Object.seal restrict object modifications and when to use each for immutability and safety.