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Christian A. Castro
Christian A. Castro
30,501 Points

Ambiguous type name 'Index' in 'Array' PLEASE HELP!!! Mutating the Data Source | Introduction to Table Views

For some reason I'm having a problem with the outerIndex and innerIndex declarations. Error "Ambiguous type name 'Index' in 'Array'"..

I have been looking around, but apparently there's no answer or good explanation for it.

Apparently there was a typealias keyword used before, however I still getting the same error message..

var outIndex: Array.Index? = nil

However I still getting the same error message... "Ambiguous type name 'index' in Array'"

Hi Christian,

I could do with a link to the course you're doing but have you tried .index rather than .Index? i.e. no capitalisation.


1 Answer

It appears this is mostly abstracted away now. You just need to get the index path then the object itself and update from there.

extension ContactListController: ContactDetailControllerDelegate {
    func didMarkAsFavoriteContact(_ contact: Contact) {
        guard let indexPath = dataSource.indexPath(for: contact) else {

        var favoriteContact = dataSource.object(at: indexPath)
        favoriteContact.isFavorite = true

        dataSource.updateContact(favoriteContact, at: indexPath)