Coding Standards

Naming Conventions

Tip	Format	Ornek
Variable	camelCase	userName, itemCount
Function	camelCase, verb-first	getUserById, calculateTotal
Class/Type	PascalCase	UserService, OrderItem
Constant	UPPER_SNAKE	MAX_RETRIES, API_URL
File	kebab-case	user-service.ts, order-item.ts
Boolean	is/has/should prefix	isActive, hasPermission

Immutability

// YANLIS: Mutate
user.name = newName;
items.push(newItem);

// DOGRU: Yeni obje
const updated = { ...user, name: newName };
const newItems = [...items, newItem];

Error Handling

// Custom error class
class AppError extends Error {
  constructor(public code: string, message: string, public statusCode = 500) {
    super(message);
  }
}

// Try-catch with specific errors
try {
  const result = await riskyOperation();
  return result;
} catch (error) {
  if (error instanceof ValidationError) {
    throw new AppError('VALIDATION', error.message, 400);
  }
  throw new AppError('INTERNAL', 'Unexpected error', 500);
}

Function Rules

• Max 50 satir, tek sorumluluk
• Max 3 parametre (fazlasi obje olarak)
• Early return (nested if yerine guard clause)
• Pure function tercih et (side effect yok)

// YANLIS: Deep nesting
function process(user) {
  if (user) {
    if (user.isActive) {
      if (user.hasPermission) {
        return doWork(user);
      }
    }
  }
}

// DOGRU: Early return
function process(user) {
  if (!user) return null;
  if (!user.isActive) return null;
  if (!user.hasPermission) return null;
  return doWork(user);
}

SOLID Principles