Demeter's Law in PHP: Principle, Examples, and Best Practices

Demeter's Law, also known as the principle of least knowledge, states that objects should only interact with their immediate components rather than accessing nested properties through long chains of calls. This programming principle helps prevent the common "train wreck pattern" where code like `$order->getCustomer()->getAddress()->getCity()` creates tight coupling and fragile dependencies. By delegating responsibilities to appropriate objects and avoiding excessive chained calls, developers can create more robust, readable, and maintainable code that better withstands internal structural changes.