Append unique values to an array in swift

Question

I haven't found anything on that in Swift. Have found how to find unique values on an array, but not this. Sorry if it sounds quite basic...

But I have the following array

var selectedValues = [String]()

And the following value that comes from a Parse query

 var objectToAppend = object.objectForKey("description")! as! String

this is how I'am doing it at the moment.

self.selectedHobbies.append(objectToAppend)

But because the query happens repeated times, it ends up appending repeated values. It works, but I just want to not waste memory and only keep unique values.

Any ideas on how to solve that in swift?

Answer 1

You can use a Set which guarantees unique values.

var selectedValues = Set<String>()
// ...
selectedValues.insert(newString) // will do nothing if value exists

Of course, the elements of a Set are not ordered.

If you want to keep the order, just continue with the Array but check before you insert.

if !selectedValues.contains("Bar") { selectedValues.append("Bar") }