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// RUN: %target-run-simple-swift(-parse-as-library -Xfrontend -disable-availability-checking) | %FileCheck %s
// REQUIRES: executable_test
// REQUIRES: concurrency
// UNSUPPORTED: freestanding
// rdar://76038845
// REQUIRES: concurrency_runtime
// UNSUPPORTED: back_deployment_runtime
enum GeneralError : Error {
case UnknownBallKind
case Todo
}
enum BallKind {
case MostLostV1
case Chromehard
case PT5
case KirksandLignature
}
@available(SwiftStdlib 5.1, *)
class Specs {
// obtains the number of dimples
subscript(_ bk : BallKind) -> Int {
get throws {
switch (bk) {
case .MostLostV1:
return 450
case .Chromehard:
return 125
default:
throw GeneralError.UnknownBallKind
}
}
}
}
@available(SwiftStdlib 5.1, *)
actor Database {
var currentData : Specs {
get async {
let handle = detach { Specs() }
print("obtaining specs...")
return await handle.get()
}
}
var hasNewData : Bool {
get throws { return true }
}
}
@available(SwiftStdlib 5.1, *)
protocol SphericalObject {
var name : String { get async throws }
var dimples : Int { get async throws }
var description : String { get async throws }
}
@available(SwiftStdlib 5.1, *)
class Ball : SphericalObject {
var name : String { get async throws { throw GeneralError.Todo } }
var dimples : Int { get async throws { throw GeneralError.Todo } }
var description : String { get async throws { throw GeneralError.Todo } }
}
@available(SwiftStdlib 5.1, *)
class GolfBall : Ball {
private static let db : Database = Database()
private var _model : BallKind
private var _dimples : Int?
init(_ bk : BallKind) {
_model = bk
}
override var name : String {
return "golf ball"
}
override var description : String {
get async throws {
return "this \(name) has \(await dimples) dimples"
}
}
override var dimples : Int {
get async {
let newData = (try? await GolfBall.db.hasNewData) ?? false
if newData || _dimples == nil {
let specs = await GolfBall.db.currentData
_dimples = (try? specs[_model]) ?? 0
}
return _dimples!
}
}
}
// CHECK: obtaining specs...
// CHECK: this golf ball has 450 dimples
// CHECK: obtaining specs...
// CHECK: this golf ball has 125 dimples
// CHECK: obtaining specs...
// CHECK: this golf ball has 0 dimples
// CHECK: obtaining specs...
// CHECK: this golf ball has 0 dimples
@available(SwiftStdlib 5.1, *)
func printAsBall(_ b : Ball) async {
print(try! await b.description)
}
@available(SwiftStdlib 5.1, *)
func printAsAsSphericalObject(_ b : SphericalObject) async {
print(try! await b.description)
}
@available(SwiftStdlib 5.1, *)
@main struct RunIt {
static func main() async {
let balls : [(Bool, Ball)] = [
(true, GolfBall(.MostLostV1)),
(false, GolfBall(.Chromehard)),
(true, GolfBall(.PT5)),
(false, GolfBall(.KirksandLignature))
]
for (useProtocol, ball) in balls {
if (useProtocol) {
await printAsAsSphericalObject(ball)
} else {
await printAsBall(ball)
}
}
}
}
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