Design Pattern: The Renderless Component Pattern for UI Logic Reuse

Renderless components handle logic and state but don't render any HTML of their own, passing data to parents via Scoped Slots.

This pattern separates 'Behavior' from 'Presentation'. For example, a PasswordValidator component can handle the logic of checking length and special characters, then pass the 'isValid' state and 'validate' function to the parent. The parent then decides whether to show a red border, an icon, or a text message. This is more flexible than Props/Events for complex UI behaviors.