Classes and decorators

Why a class

A component keeps three things together: the data it remembers, the code that changes that data, and the code that draws it. A class is a natural home for all three — they share one this, so they can reach each other without being passed around, and the component has a real identity that survives re-renders. State is just a field; there is no separate place for it to live and no rules about when you may read it.

It also makes reuse first-class. Because a component is a class, one component can extend another — keep what it had, change what differs — which is where a lot of the framework's composition story comes from.

Why decorators, not reserved method names

Lifecycle and state are decorators — @state, @created, @mounted, @updated — rather than special method names you are expected to implement.

The reason is collisions. If "the method named mount runs on mount", then mount is a name you can never use for anything else, on any component, ever — and nothing warns you when you shadow it by accident. A decorator attaches the behaviour without claiming the name: @mounted ready() runs on mount, and ready is still just a method you named. (render is the one exception — it is abstract, so the compiler forces exactly one and the collision can't happen.)

Why your methods are already bound

onclick={this.increment} works — you don't write a constructor or an arrow-field to keep this. Ramonda binds your methods to the instance when the component is built.

That is not only convenience: a decorator can't be applied to an arrow-function field, so if the way to keep this were an arrow field, you couldn't decorate your handlers. Binding ordinary methods is what keeps @memoized and the event decorators usable on them.

Why TC39 decorators

Ramonda uses the standard (TC39 stage-3) decorators — the ones on their way into JavaScript itself — not the older experimental TypeScript ones. That is why installation asks your bundler to transpile them: they are new enough that not every runtime parses them yet, but they are the version with a future.