import Foundation
import Combine

enum  WeatherError : Error {
case  thingsJustHappen
}

let  Publisher = PassthroughSubject<Int, WeatherError>()

let  subscriber = Publisher
.filter{$0 > 25}
.sink(receiveCompletion: {_ in}, receiveValue: {print("reseive value is \($0)")})


let anotherSubscriber = Publisher.handleEvents(receiveSubscription: {Subscription in print("New Subscription is \(Subscription)")}, 
receiveOutput: {output in print("New Value output is \(output)")}, receiveCompletion: {error in print("Subscription completed with potential error is \(error)")}, 
receiveCancel: {print("Subscription Canseled")})
.sink(receiveCompletion: {_ in}, receiveValue: {print("reseive value is \($0)")})


Publisher.send(30)
Publisher.send(20)
Publisher.send(completion: Subscribers.Completion<WeatherError>.failure(.thingsJustHappen))
Publisher.send(100)

New Subscription is PassthroughSubject
reseive value is 30
New Value output is 30
reseive value is 30
New Value output is 20
reseive value is 20
Subscription completed with potential error is failure(__lldb_expr_1.WeatherError.thingsJustHappen)

import SwiftUI
import Combine

struct ContentView: View {
    @ObservedObject private var inputchar = RestrictInput(5)
    var body: some View {
        Form{
            TextField("input text", text: $inputchar.text)
            .textFieldStyle(RoundedBorderTextFieldStyle())
            .padding()
            Text("入力されたのは、\(inputchar.text)")
        }
    }
}


//文字を規定数入力すると消してくれるクラス
class RestrictInput: ObservableObject {
    @Published var text = ""
    private var canc: AnyCancellable!
    init (_ maxLength: Int) {
        canc = $text
            .debounce(for: 1, scheduler: DispatchQueue.main)
            .map { String($0.prefix(maxLength)) }
            .assign(to: \.text, on: self)
    }
    deinit {
        canc.cancel()
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}