swift-mirror/stdlib/stdlib.docc/Observation/Observation.observable-swift.macro.md

Observation/Observable()

@Metadata { @DocumentationExtension(mergeBehavior: override) }

Defines and implements conformance of the Observable protocol.

This macro adds observation support to a custom type and conforms the type to the Observation/Observable protocol. For example, the following code applies the Observable macro to the type Car making it observable:

@Observable 
class Car {
   var name: String = ""
   var needsRepairs: Bool = false

   init(name: String, needsRepairs: Bool = false) {
       self.name = name
       self.needsRepairs = needsRepairs
   }
}