Failed to produce diagnostic for expression; please submit a bug report (https://swift.org/contributing/#reporting-bugs) and include the project

import SwiftUI

struct ContentView: View { @State private var checkAmount = 0.0 @State private var numberOfPeople = 2 @State private var tipPercentage = 20 @FocusState private var amountIsFocused: Bool

let tipPercentages = [0..<101]

var totalPerPerson: Double {
    // calculate the total per person here
    let peopleCount = Double(numberOfPeople + 2)
    let tipSelection = Double(tipPercentage)

    let tipValue = checkAmount / 100 * tipSelection
    let grandTotal = checkAmount + tipValue
    let amountPerPerson = grandTotal / peopleCount

    return amountPerPerson

}

var total: Double {
    let tipSelection = Double(tipPercentage)
    let tipValue = checkAmount / 100 * tipSelection
    let grandTotal = checkAmount + tipValue
    return grandTotal
}
var body: some View {
    NavigationView {
    Form {
        Section {
            TextField("Amount", value: $checkAmount, format: .currency(code: Locale.current.currencyCode ?? "USD"))
                .keyboardType(.numberPad)
                .focused($amountIsFocused)

        Picker("Number of people", selection: $numberOfPeople) {
                ForEach(2..<100) {
                    Text("\($0) people")
                }
            }
        }

        Section {
            Picker("Tip percentage", selection: $tipPercentage) {
                ForEach(tipPercentages, id: \.self) {
                    Text($0, format: .percent)
                }
            }
            .pickerStyle(.segmented)
        } header: {
            Text("How much tip do you want to leave?")
        }
        Section {
            Text(totalPerPerson, format: .currency(code: Locale.current.currencyCode ?? "USD" ))
        }
    }
    .navigationTitle("WeSplit")
    .toolbar {
        ToolbarItemGroup(placement: .keyboard) {
            Spacer()
            Button("Done") {
                amountIsFocused = false
            }
        }
    }
        Section {
            Text(total, format: .currency(code: Locale.current.currencyCode ?? "USD" ))
      }
   }
}

} struct ContentView_Previews: PreviewProvider { static var previews: some View { ContentView() } }

Two problems:

1. You have an extra Section outside the Form there at the bottom of the body.
2. Your tipPercentages is not correct. You have:

let tipPercentages = [0..<101]

but this makes tipPercentages a type [Range<Int>]. That's not going to work when you put it in a ForEach. You want it to be something like this:

let tipPercentages = [10, 15, 20, 25, 0]

which would be of type [Int].

(If you truly want to allow the user to select any tip percentage from 0 to 100, you can do this:

let tipPercentage = 0..<101

But given that this is a segmented Picker, that seems less than advisable, since the system will try to fit all 101 of those options on one line! You would need to use a regular Picker.)

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May I add?

This is not a very useful title: I have a problem. Help me please.

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