Implement basic error view

Example/ExampleApp/Sources/ErrorFeature/ErrorFeature.swift

@@ -2,7 +2,11 @@ import ComposableArchitecture
 import SwiftUI
 
 public struct ErrorState: Equatable {
-  public init() {}
+  public init(error: NSError) {
+    self.error = error
+  }
+
+  var error: NSError
 }
 
 public enum ErrorAction: Equatable {}

Example/ExampleApp/Sources/ErrorFeature/ErrorView.swift

@@ -7,14 +7,33 @@ public struct ErrorView: View {
   }
 
   let store: Store<ErrorState, ErrorAction>
+  @Environment(\.dismiss) var dismiss
 
   struct ViewState: Equatable {
-    init(state: ErrorState) {}
+    let error: NSError
+
+    init(state: ErrorState) {
+      error = state.error
+    }
   }
 
   public var body: some View {
     WithViewStore(store.scope(state: ViewState.init)) { viewStore in
-      Text("ErrorView")
+      NavigationView {
+        Form {
+          Text("\(viewStore.error)")
+        }
+        .navigationTitle("Error")
+        .toolbar {
+          ToolbarItem(placement: .cancellationAction) {
+            Button {
+              dismiss()
+            } label: {
+              Image(systemName: "xmark")
+            }
+          }
+        }
+      }
     }
   }
 }
@@ -23,7 +42,9 @@ public struct ErrorView: View {
 public struct ErrorView_Previews: PreviewProvider {
   public static var previews: some View {
     ErrorView(store: .init(
-      initialState: .init(),
+      initialState: .init(
+        error: NSError(domain: "preview", code: 1234)
+      ),
       reducer: .empty,
       environment: ()
     ))