Clean Code: DRY (Do not Repeat Yourself)

Refactor repeated code into functions to avoid duplication and make your code more maintainable.

Let's explore some examples in TypeScript to help you grasp the concept:

// Bad
function getFullName(user: { firstName: string; lastName: string }): string {
  return `${user.firstName} ${user.lastName}`;
}

function getGreeting(user: { firstName: string; lastName: string }): string {
  return `Hello, ${user.firstName} ${user.lastName}!`;
}

// Good
function getFullName(user: { firstName: string; lastName: string }): string {
  return `${user.firstName} ${user.lastName}`;
}

function getGreeting(user: { firstName: string; lastName: string }): string {
  return `Hello, ${getFullName(user)}!`;
}