Swift2: Array extension to remove object by value - Foundation

Question

I have edited the question to focus on the last error. This is the last error in my code: an Array extension to remove object by value

It seems to be related to this post too:

Array extension to remove object by value

But I am stuck :x

func cell(cell: FriendSearchTableViewCell, didSelectUnfollowUser user: PFUser) {
    if var followingUsers = followingUsers {
        ParseHelper.removeFollowRelationshipFromUser(PFUser.currentUser()!, toUser: user)
        // update local cache
        removeObject(user, fromArray: &followingUsers)
        self.followingUsers = followingUsers
    }

// for the 'removeObject' an error is raised:

Use of unresolved identifier 'removeObject'

The function is calling the framework Foundation through a Array+RemoveObject.swiftfile which states:

import Foundation

// Thanks to Martin R: https://stackoverflow.com/questions/24938948/array-extension-to-remove-object-by-value

extension Array where Element : Equatable {
  // Remove first collection element that is equal to the given `object`:
mutating func removeObject(object : Generator.Element) {
        if let index = self.indexOf(object) {
            self.removeAtIndex(index)
        }
    }
}

I am not sure my workspace is properly understanding that he needs to refer to this swift file to find the details of the identified removeObject.

Make sure to include all of the relevant code to *help others help you* -- right now the pieces that are causing you errors are not included in your code snippets. The error is saying that you cannot cast `PFQueryArrayResultBlock` to whatever `updateList` is. I can't find the definition for `updateList` anywhere in the included code so it's tough to help. The other error saying unresolved identifier `removeObject` is the same thing. Where is `removeObject` defined? The compiler can't find it and that's what's causing the error — Russell, Nov 04 '15 at 23:00
You are totally right, and thank you for your comment. I looked for the 'updateList' and discovered that it was referring to AnyObject and not PFObject. I made the change and it solved the three errors!!! I still have the last one. It refers to the framework "Foundation" where: `import Foundation extension RangeReplaceableCollectionType where Generator.Element : Equatable { // Remove first collection element that is equal to the given `object`: mutating func removeObject(object : Generator.Element) { if let index = self.indexOf(object) { self.removeAtIndex(index) } } }` — Jeremy, Nov 04 '15 at 23:28
A suggested version for Swift2 is: `extension Array { mutating func removeObject(object: T) -> Bool { var index: Int? for (idx, objectToCompare) in self.enumerate() { if let toCompare = objectToCompare as? T { if toCompare == object { index = idx break } } } if(index != nil) { self.removeAtIndex(index!) return true } else { return false } } }` But how to edit the code — Jeremy, Nov 05 '15 at 00:24
@Jeremy add it to the end of your array. Ex: followingUsers.removeObject(user) — Leo Dabus, Nov 05 '15 at 00:47
@LeoDabus thank you for your help. I have tried but now I get a new error based on the PFObject value: `// update local cache followingUsers.removeObject(user) self.followingUsers = followingUsers` Gives two errors `Value of type '[PFUser]?' has no member 'removeObject'`and `Assigning a property to itself` — Jeremy, Nov 05 '15 at 14:10

score 0 · Accepted Answer · answered Nov 05 '15 at 15:15

PFUser does not conform to Equatable protocol so your extension doesn't apply. But a PFUser is identified through its user name. You can solve your problem with filter, no extension required:

func cell(cell: FriendSearchTableViewCell, didSelectUnfollowUser user: PFUser) {
    if var followers = followingUsers {
        ParseHelper.removeFollowRelationshipFromUser(PFUser.currentUser()!, toUser: user)
        // update local cache
        followers = followers.filter { $0.username != user.username } 
        self.followingUsers = followers
    }
}

Swift2: Array extension to remove object by value - Foundation

1 Answers1