JS Practice — Built-in Objects

Interface — Readonly Properties

📖 Usage Example

interface Config { readonly host: string; readonly port: number }
const cfg = createFrozenConfig('localhost', 3000)
Object.isFrozen(cfg)   // → true

readonly interface properties cannot be reassigned; Object.freeze enforces this at runtime.

Interfaces: readonly + Object.freeze

readonly properties can be set at creation but not mutated afterward. Object.freeze() enforces this at runtime.

Challenge: Implement createFrozenConfig(host, port) returning a frozen object.

const cfg = createFrozenConfig('localhost', 3000)
Object.isFrozen(cfg) // → true

💡 Hints (1)