// A project extension
interface MessageExtension {
    // A configurable greeting
    Property<String> getGreeting()
}

// A task that displays a greeting
abstract class Greeting extends DefaultTask {
    // Configurable by the user
    @Input
    abstract Property<String> getGreeting()

    // Read-only property calculated from the greeting
    @Internal
    final Provider<String> message = greeting.map { it + ' from Gradle' }

// A project extension
interface MessageExtension {
    // A configurable greeting
    abstract val greeting: Property<String>
}

// A task that displays a greeting
abstract class Greeting : DefaultTask() {
    // Configurable by the user
    @get:Input
    abstract val greeting: Property<String>

    // Read-only property calculated from the greeting
    @Internal
    val message: Provider<String> = greeting.map { it + " from Gradle" }