name: typescript_advanced
router_kit: FullStackKit
description: TypeScript 5+ advanced patterns, type utilities and best practices guide.
metadata:
skillport:
category: development
tags: [architecture, automation, best practices, clean code, coding, collaboration, compliance, debugging, design patterns, development, documentation, efficiency, git, optimization, productivity, programming, project management, quality assurance, refactoring, software engineering, standards, testing, typescript advanced, utilities, version control, workflow] - patterns

📘 TypeScript Advanced

TypeScript 5+ advanced patterns guide.

📋 Utility Types

// Partial - tüm prop'lar optional
type PartialUser = Partial<User>;

// Required - tüm prop'lar required
type RequiredUser = Required<User>;

// Pick - seçili prop'lar
type UserName = Pick<User, 'id' | 'name'>;

// Omit - prop'ları çıkar
type UserWithoutPassword = Omit<User, 'password'>;

// Record - key-value map
type UserMap = Record<string, User>;

// ReturnType - fonksiyon return tipi
type Result = ReturnType<typeof fetchUser>;

🔧 Advanced Patterns

Discriminated Unions

type Result<T> = 
  | { success: true; data: T }
  | { success: false; error: string };

function handle(result: Result<User>) {
  if (result.success) {
    console.log(result.data); // User
  } else {
    console.log(result.error); // string
  }
}

Template Literal Types

type EventName = `on${Capitalize<string>}`;
// "onClick", "onHover", etc.

type Route = `/${string}`;

Conditional Types

type NonNullable<T> = T extends null | undefined ? never : T;

type Flatten<T> = T extends Array<infer U> ? U : T;

🎯 Zod Integration

import { z } from 'zod';

const UserSchema = z.object({
  id: z.string().uuid(),
  email: z.string().email(),
  age: z.number().min(0).max(120),
});

type User = z.infer<typeof UserSchema>;

⚡ Best Practices

1. Strict mode always on
2. Avoid any - use unknown instead
3. Prefer interfaces for objects
4. Use const assertions for literals
5. Type narrowing over type assertions

🔄 Workflow

Source: TypeScript 5.0 Release Notes & Total TypeScript Best Practices

Phase 1: Type Design & Schema

• [ ] Interface vs Type: Use interface for object structures, type aliases for unions and complex types.
• [ ] Zod Validation: Define schemas for runtime security and derive TS types with z.infer.
• [ ] Strict Check: Verify that strict: true setting is active in tsconfig.json.

Phase 2: Advanced Logic Implementation

• [ ] Type Narrowing: Narrow unknown types using type guards (is, in) or asserts.
• [ ] Conditional & Mapped Types: Use T extends U ? X : Y structures to make repetitive types dynamic.
• [ ] Generic Constraints: Increase type safety by constraining generic types with extends.

Phase 3: Refactoring & Verification

• [ ] Remove any: Replace all any usages with unknown or specific union types.
• [ ] Performance Audit: Verify that complex recursive types do not affect build time.
• [ ] Documentation: Document advanced types with @param, @returns and @typeParam tags.

Checkpoints

TypeScript Advanced v1.5 - With Workflow