annotation
@Handles
@Handles(Event) handler Name { … }
@Handles is a declarative annotation that names the event or subsystem a handler (or a whole program) is responsible for. The parser accepts and records it as metadata for analysis and tooling — it does not by itself wire up dispatch, so it documents intent rather than driving execution. When you want a handler to actually run in response to an event, use @On(Event), which registers the listener; @Handles is the companion label that makes ownership of an event legible across a modular codebase. Keep the named symbol a real event or system so the annotation stays meaningful.
Example
program CombatModule {
property Health { current: int = 100 }
model Enemy { Health }
event DamageDealt { amount: int = 0 }
@Handles(DamageDealt) # documents this handler's responsibility
@On(DamageDealt) handler ApplyDamage { # @On does the actual dispatch wiring
for (Health) in query [Health, {Enemy}] {
Health.current = Health.current - amount
}
}
entry {
spawn Enemy { Health { current: 100 } }
emit DamageDealt(amount: 25)
}
}