Patterns That Matter
Observer & reactivity
Lesson 2 of 5
Observer is pub/sub, and it is the machinery underneath event emitters, signals, and reactive UIs.
What you'll learn
- Recognize the Observer pattern as pub/sub, the foundation of reactive systems.
- See how signals and event emitters are Observer with better ergonomics.
- Build a tiny emitter with subscribe and emit that notifies all subscribers.
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