If a Bird class has a fly() method, a Penguin subclass shouldn't override it to throw an error, as this violates the expectation that all birds in the system can fly. I: Interface Segregation Principle (ISP)
Depend on abstractions (interfaces), not concrete implementations.
A class should not be forced to implement methods it does not use. php-guide.7z
A class should have one, and only one, reason to change.
The request for a "solid story" for php-guide.7z refers to the of Object-Oriented Programming (OOP) applied to PHP development. These five design principles—Single Responsibility, Open-Closed, Liskov Substitution, Interface Segregation, and Dependency Inversion—form the "story" or fundamental logic for writing maintainable, scalable, and professional PHP code. 🧩 The SOLID Framework for PHP If a Bird class has a fly() method,
Classes should be open for extension but closed for modification.
Objects of a superclass should be replaceable with objects of its subclasses without breaking the application. A class should have one, and only one, reason to change
In Laravel or standard PHP, a UserController should only handle HTTP requests. It should not directly calculate payroll or send emails; those tasks belong in separate services or observers. O: Open-Closed Principle (OCP)