ObservableState
Defines and implements conformance of the Observable protocol.
@attached(extension, conformances: Observable, ObservableState) @attached(member, names: named(_$id), named(_$observationRegistrar), named(_$willModify)) @attached(memberAttribute) macro ObservableState()
Conformance
Change tracking
struct ObservableStateID
A unique identifier for a observed value.
struct ObservationStateRegistrar
Provides storage for tracking and access to data changes.