Til: English

O’zbek

Open/Closed Principle (OCP)

Dasturiy tizimlar kengaytirish uchun ochiq, lekin o’zgartirish uchun yopiq bo’lishi kerak.

Yangi funksionallikni mavjud kodni o’zgartirmasdan qo’shish imkoni bo’lishi kerak. Bunga odatda inheritance (meros olish) va polymorphism (polimorfizm) orqali erishiladi.

Diagramma

Noto’g’ri yondashuv

violation.py dagi AreaCalculator har bir shakl turini isinstance tekshiruvi orqali aniqlaydi:

class AreaCalculator:
    @staticmethod
    def calculate(shape: object) -> float:
        if isinstance(shape, Rectangle):
            return shape.width * shape.height
        if isinstance(shape, Circle):
            return math.pi * shape.radius ** 2
        raise TypeError(f"Unknown shape: {type(shape).__name__}")

Triangle qo’shish uchun mavjud AreaCalculator klassini o’zgartirish kerak — bu o’zgartirish uchun yopiq emas.

To’g’ri yondashuv

correct.py dagi Shape abstrakt klassi area() metodini belgilaydi. Har bir shakl o’z hisob-kitobini mustaqil bajaradi:

class Shape(ABC):
    @abstractmethod
    def area(self) -> float: ...

class Triangle(Shape):
    def __init__(self, base: float, height: float) -> None:
        self.base = base
        self.height = height

    def area(self) -> float:
        return 0.5 * self.base * self.height

Yangi shakl qo’shish — faqat yangi subklass yaratish. Mavjud kodga hech qanday o’zgartirish kiritilmaydi.