✨Implement simple form validation

Author: peterfriese

SwiftUI-Combine/ContentView.swift

@@ -14,6 +14,19 @@ class UserModel: ObservableObject {
   @Published var password = ""
   @Published var passwordAgain = ""
   @Published var valid = false
+  
+  private var cancellableSet: Set<AnyCancellable> = []
+  
+  init() {
+    $userName
+      .debounce(for: 0.8, scheduler: RunLoop.main)
+      .removeDuplicates()
+      .map { input in
+        return input.count >= 3
+      }
+      .assign(to: \.valid, on: self)
+      .store(in: &cancellableSet)
+  }
 }
 
 struct ContentView: View {
@@ -39,7 +52,7 @@ struct ContentView: View {
   }
 
 }
-  
+
 struct ContentView_Previews: PreviewProvider {
   static var previews: some View {
     ContentView()