ChatGPT’s code writing

This week, the internet has been all about ChatGPT, the rather remarkable natural language AI with a very large model. If you’re a twitter user, you were probably amazed, but now eventually tired of seeing examples of it’s output. I’ll add to that with an example of a SwifUI CoreData based todo app it wrote for me from a single sentence prompt below. Rather than look at other people’s examples you should definitely go and play with it yourself – it is very impressive. Along with the image based AI’s it’s made 2022 into a historical year for AI.

ChatGPT will write software. I can’t see it replacing developers, but it seems likely there’ll be a bunch of interesting tools to come over the next few years. I feel like the first big effect will be the volume of mediocre internet content will increase dramatically as it is pretty great at run of the mill copy-writing. I’d like to assure my readers that all my mediocre internet content will continue to be human written – with the exception of most of the art, and the code example below :- )

write swiftui code for a todo application where the items reoccur after a certain number of days. The items are shown in a list and the user can navigate to a detail view.

me

Here is an example of SwiftUI code for a todo application where the items reoccur after a certain number of days:

ChatGPT

	struct TodoItem: Identifiable {
	let id = UUID()
	let task: String
	let dueDate: Date
	let repeatInterval: Int // number of days until the task reoccurs
	}
	struct TodoList: View {
	@State var items = [TodoItem]()
	var body: some View {
	List(items) { item in
	NavigationLink(destination: TodoDetail(item: item)) {
	Text(item.task)
	}
	}
	}
	}
	struct TodoDetail: View {
	let item: TodoItem
	var body: some View {
	VStack {
	Text(item.task)
	Text("Due: \(item.dueDate, formatter: DateFormatter.mediumDate)")
	Text("Reoccurs every: \(item.repeatInterval) days")
	}
	}
	}

view raw GPTTodo1.swift hosted with ❤ by GitHub

In the TodoList view, a List is used to display the todo items. Each item in the list is wrapped in a NavigationLink that takes the user to a TodoDetail view when tapped. The TodoDetail view displays the task, the due date, and the repeat interval for the selected todo item.

You can modify this code to suit your specific needs, such as adding features to add or delete items, or changing the layout and appearance of the views.

ChatGPT

That’s pretty cool. I don’t think that DateFormatter.mediumDate is a thing, so I changed that line to:

Text("Due: \(item.dueDate, style: .date)")

It’s okay ChatGPT, I get confused about the variety of ways to change dates too.

great. show me the content view code that contains the TodoList and has a button to add items.

me

Here is an example of a ContentView that contains a TodoList and has a button to add items:

ChatGPT

	struct ContentView: View {
	@State var items = [TodoItem]()
	var body: some View {
	VStack {
	TodoList(items: $items)
	Button(action: {
	// add new todo item here
	}) {
	Text("Add Item")
	}
	}
	}
	}

view raw GPTTodo2.swift hosted with ❤ by GitHub

In this code, the ContentView contains a TodoList and a Button. The TodoList is initialized with the items array, which is marked as @State so that it can be modified in response to user actions. The Button has an action closure that is executed when the button is tapped. You can add code inside this closure to create a new TodoItem and add it to the items array.

You can modify this code to suit your specific needs, such as changing the layout and appearance of the views, or adding features to delete items from the list.

ChatGPT

To let this compile, I commented out the Preview and changed the items property in the top of the TodoList view to a binding:

struct TodoList: View {
    @Binding var items: [TodoItem]

thank you. what would the code for adding an item look like

me

Here is an example of code that you can use to add a new TodoItem to the items array when the button is tapped:

ChatGPT

	struct ContentView: View {
	@State var items = [TodoItem]()
	var body: some View {
	VStack {
	TodoList(items: $items)
	Button(action: {
	let newItem = TodoItem(task: "New Task", dueDate: Date(), repeatInterval: 7)
	items.append(newItem)
	}) {
	Text("Add Item")
	}
	}
	}
	}

view raw GPTTodo3.swift hosted with ❤ by GitHub

In this code, the Button has an action closure that creates a new TodoItem with the task “New Task”, a due date of the current date, and a repeat interval of 7 days. The new item is then appended to the items array.

You can modify this code to suit your specific needs, such as prompting the user for the task name and due date, or changing the default repeat interval. You can also add additional logic to handle errors or validation failures when creating the new item.

ChateGPT

This all runs and the add item works, but the NavigationLink to get to the detail view does not. Let’s wrap it in a NavigationView to fix that.

struct ContentView: View {
    @State var items = [TodoItem]()

    var body: some View {
        NavigationView {
            VStack {
                TodoList(items: $items)
                Button(action: {
                    let newItem = TodoItem(task: "New Task", dueDate: Date(), repeatInterval: 7)
                    items.append(newItem)
                }) {
                    Text("Add Item")
                }
            }
        }
    }
}

I went on to ask it to change this to core data for persistence, but as I wanted the app to be more and more complex, it needed me to fix more and more problems, and became less fun.