علاقة "is-a"

// الفئة الأساسية - ما هي عليه جميعاً
class Book {
  constructor(title, author, pages) {
    this.title = title;
    this.author = author;
    this.pages = pages;
  }
  
  read() {
    console.log(`Reading ${this.title} by ${this.author}`);
  }
}

// الرواية هي كتاب (وراثة صحيحة)
class Novel extends Book {
  constructor(title, author, pages, genre) {
    super(title, author, pages);
    this.genre = genre;
  }
}

// استخدام الفئات
const fiction = new Novel("1984", "George Orwell", 328, "Dystopian");
fiction.read();    // "Reading 1984 by George Orwell" - موروثة من Book