console out

name = UITextFieldTextDidChangeNotification, object = Optional(<UITextField: 0x14c836800; frame = (150 300; 200 20); opaque = NO; focused = YES; gestureRecognizers = <NSArray: 0x6000027e7cf0>; text = 'Hello World'; borderStyle = None; background = <_UITextFieldNoBackgroundProvider: 0x600002bd0500: textfield=<UITextField 0x14c836800>>; layer = <CALayer: 0x600002985b80>>), userInfo = nil
name = UITextFieldTextDidChangeNotification, object = Optional(<UITextField: 0x14c836800; frame = (150 300; 200 20); opaque = NO; focused = YES; gestureRecognizers = <NSArray: 0x6000027e7cf0>; text = 'Hello Worl'; borderStyle = None; background = <_UITextFieldNoBackgroundProvider: 0x600002bd0500: textfield=<UITextField 0x14c836800>>; layer = <CALayer: 0x600002985b80>>), userInfo = nil
name = UITextFieldTextDidChangeNotification, object = Optional(<UITextField: 0x14c836800; frame = (150 300; 200 20); opaque = NO; focused = YES; gestureRecognizers = <NSArray: 0x6000027e7cf0>; text = 'Hello Wor'; borderStyle = None; background = <_UITextFieldNoBackgroundProvider: 0x600002bd0500: textfield=<UITextField 0x14c836800>>; layer = <CALayer: 0x600002985b80>>), userInfo = nil

LearningCombine.playground

import UIKit
import PlaygroundSupport
import Combine

class MyViewController : UIViewController {
        
    var sub: AnyCancellable!
    
    override func loadView() {
        let view = UIView()
        view.backgroundColor = .white
        
        let label = UILabel()
        label.frame = CGRect(x: 150, y: 200, width: 200, height: 20)
        label.text = "Hello World!"
        label.textColor = .black
        
        view.addSubview(label)
        
        let textField = UITextField()
        textField.frame = CGRect(x:150, y: 300, width: 200, height: 20)
        textField.text = "Hello World!"
        textField.textColor = .black
        
        sub = NotificationCenter.default
            .publisher(for: UITextField.textDidChangeNotification, object: textField)
            .sink(receiveCompletion: { print ($0) },
                  receiveValue: { print ($0) })
        
        view.addSubview(textField)
        
        self.view = view
    }
}
    
// Present the view controller in the Live View window
PlaygroundPage.current.liveView = MyViewController()