[Move onChange into binding]

OnChangeBinding.swift

import SwiftUI

struct ContentView: View {
  @State private var rating = 0.0
  
  var body: some View {
    Slider(value: $rating.onChange(sliderChanged))
  }
      
  func sliderChanged(_ value: Double) {
    print("Rating changed to \(value)")
  }
}

extension Binding {
  func onChange(_ handler: @escaping (Value) -> Void) -> Binding<Value> {
    Binding(
      get: { self.wrappedValue },
      set: { newValue in
            self.wrappedValue = newValue
            handler(newValue)
           }
    )
  }
}