19. Consumer.swi,
public final class Consumer<T>: Sink {
public typealias Element = Event<T>
public let disposable = CompositeDisposable()
public init<S: Sink where S.Element == Event<T>>(_ sink: S)
public convenience init(put: Event<T> -> ())
public convenience init(
next: T -> () = emptyNext,
error: NSError -> () = emptyError,
completed: () -> () = emptyCompleted)
public func put(event: Event<T>)
}
20. Consumerの使用例
extension Producer {
public func asDeferredRACSignal<U: AnyObject>(evidence: Producer<T> -> Producer<U?>) -> RACSignal {
return RACSignal.createSignal { subscriber in
let selfDisposable = evidence(self).produce { event in
switch event {
case let .Next(obj):
subscriber.sendNext(obj)
case let .Error(error):
subscriber.sendError(error)
case let .Completed:
subscriber.sendCompleted()
}
}
return RACDisposable {
selfDisposable.dispose()
}
}
}
}
22. Iden%ty.swi,
/// The identity function, which returns its argument.
///
/// This can be used to prove to the typechecker that a given type A is
/// equivalent to a given type B.
///
/// For example, the following global function is normally impossible to bring
/// into the `Signal<T>` class:
///
/// func merge<U>(signal: Signal<Signal<U>>) -> Signal<U>
///
/// However, you can work around this restriction using an instance method with
/// an “evidence” parameter:
///
/// func merge<U>(evidence: Signal<T> -> Signal<Signal<U>>) -> Signal<U>
///
/// Which would then be invoked with the identity function, like this:
///
/// signal.merge(identity)
///
/// This will verify that `signal`, which is nominally `Signal<T>`, is logically
/// equivalent to `Signal<Signal<U>>`. If that's not actually the case, a type
/// error will result.
public func identity<T>(id: T) -> T {
return id
}
25. Signal.swi*
public final class Signal<T> {
public var current: T
public init(initialValue: T, generator: SinkOf<T> -> ())
public class func constant(value: T) -> Signal<T>
public func observe<S: Sink where S.Element == T>
(observer: S) -> Disposable
public func observe(observer: T -> ()) -> Disposable
}
27. Signal/Observer(SinkOf<T>)の使用例
extension Signal {
/// Creates a "hot" RACSignal that will forward values from the receiver.
///
/// evidence - Used to prove to the typechecker that the receiver is
/// a signal of objects. Simply pass in the `identity` function.
///
/// Returns an infinite signal that will send the observable's current
/// value, then all changes thereafter. The signal will never complete or
/// error, so it must be disposed manually.
public func asInfiniteRACSignal<U: AnyObject>(evidence: Signal<T> -> Signal<U?>) -> RACSignal {
return RACSignal.createSignal { subscriber in
evidence(self).observe { value in
subscriber.sendNext(value)
}
return nil
}
}
}
29. SignalingProperty.swi1
public final class SignalingProperty<T>: Sink {
public typealias Element = T
public let signal: Signal<T>
// setするとsignalのオブザーバーに通知される
public var value: T
public init(_ defaultValue: T)
public func __conversion() -> T
public func __conversion() -> Signal<T>
public func put(value: T)
}
30. SignalingPropertyの使用例
public class Hoge {
var name: SignalingProperty<String> = SignalingProperty("")
}
public func printName(name: String) {
println(name)
}
let hoge = Hoge()
// Stringが必要なのでSignalingProperty<String>から現在の値が取り出される
printName(hoge.name)
hoge.name.signal.observe { name in
println("(name): name was changed!")
}
hoge.name.put("ikesyo")
32. Promise.swi*
public final class Promise<T> {
public let signal: Signal<T?>
// 生成時のクロージャの引数の`sink`に`put`することでresolveされる。
// 二度目以降の`put`は無視される。
public init(action: SinkOf<T> -> ())
public func start() -> Promise<T>
public func await() -> T
// Promiseのチェーン
public func then<U>(action: T -> Promise<U>) -> Promise<U>
}
33. Promiseの使用例
public final class Signal<T> {
public func firstPassingTest(pred: T -> Bool) -> Promise<T> {
return Promise { sink in
self.take(1).observe { value in
if pred(value) {
sink.put(value)
}
}
return ()
}
}
}
35. Ac#on.swi*
public final class Action<Input, Output> {
public typealias ExecutionSignal = Signal<Result<Output>?>
// RACCommand.executionSignalsと同様
public let executions: Signal<ExecutionSignal?>
public var results: Signal<Result<Output>?> // 実行結果
public var executing: Signal<Bool> // 実行中かどうか
public let enabled: Signal<Bool> // 有効かどうか
public var values: Signal<Output?> // 成功結果
public var errors: Signal<NSError?> // 失敗結果
// アクションとなるクロージャを渡す
public init(enabledIf: Signal<Bool>,
scheduler: Scheduler = MainScheduler(),
execute: Input -> Promise<Result<Output>>)
public func execute(input: Input) -> ExecutionSignal // アクションの実行
public func then<NewOutput> // アクションの合成
(action: Action<Output, NewOutput>)
-> Action<Input, NewOutput>
}