The true power of sealed classes
In my recent post, I've introduced a PHPStan extension that brings support for sealed classes and interfaces to statically analyzed PHP. Looking back, I feel I haven't stressed the main benefit enough, so here I am doing it justice.
Seal your classes with PHPStan
Sealed classes are a useful feature of Kotlin: they allow you to specify which classes are allowed to extend a sealed class (or implement a sealed interface). With the recently released PHPStan 1.9.0, you can now introduce sealed classes to your PHP codebase too!