S_A_FunctionsAndLambdas.kt

FunctionsAndLambdas.kt

data class User(val name)

interface UserDataSource {
    fun getAllUsers(
            onSuccess: (users: List<User>) -> Unit,
            onError: (err: Throwable) -> Unit
    )
}

// class UpdateDataSourceImpl: UserDataSource { .... }

UpdateDataSourceImpl().getAllUsers(
    onSuccess = { users -> print(users) }, // here you consume success state
    onError = { err -> print(err.message) } // here you consume error state
)