Hari 30: Recap & TypeScript Ecosystem

60 min Last updated 09 Apr 2026

30 Hari TypeScript — Apa yang Sudah Dipelajari

Fondasi Type System

Primitive types, Type inference, Array, Tuple
Union, Intersection, Literal types
Interface vs Type alias
Enum dan Readonly

Advanced Types

Generics dengan constraints (extends, keyof)
Utility types: Partial, Required, Pick, Omit, Record
Conditional types, Mapped types, Template literal types
infer untuk ekstraksi tipe

OOP & Patterns

Class dengan access modifiers, abstract, readonly
Decorator pattern, Builder pattern
Repository pattern dengan generics
State machine dengan discriminated unions

Ecosystem

Zod — runtime validation
tRPC — end-to-end type safety
Prisma — type-safe ORM
React + TypeScript — type-safe UI
Vitest/Jest — testing

💡 Notice: Dependency Injection Container adalah pondasi framework modern (NestJS, Angular, inversify). Generic resolve<T> memastikan type safety saat mengambil dependency.

Assignment

Final challenge: Buat mini dependency injection container yang type-safe. Container menyimpan factory functions dan bisa resolve dependencies.

Expected output:

Selamat datang!

App v1.0.0 siap!

Greeting: Selamat datang!

TS index.ts

Solution

type Factory<T> = () => T;

class Container {
    private factories = new Map<string, Factory<any>>();

resolve<T>(token: string): T {
        const factory = this.factories.get(token);
        if (!factory) throw new Error(`Token "${token}" tidak terdaftar`);
        return factory();
    }
}

const container = new Container();

container.register("greeting", () => "Selamat datang!");
container.register("version",  () => "1.0.0");
container.register("app", () => ({
    greeting: container.resolve<string>("greeting"),
    version:  container.resolve<string>("version"),
    run: () => console.log(`App v${container.resolve<string>("version")} siap!`),
}));

const greeting = container.resolve<string>("greeting");
const app      = container.resolve<{ greeting: string; version: string; run: () => void }>("app");

console.log(greeting);
app.run();
console.log(`Greeting: ${app.greeting}`);

Output