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arraysswiftdata-structureshashtable

Make all elements of array that are Hashable unique with a UUID hashValue?

I have an array of types that conform to Hashable these can be any type that conforms to hashable. The issue I'm having is that say I have an array of strings

let people = ["Joe", "Tom", "Bob", "Joe"]

if people[3] == people[people.firstIndex(of: "Joe")!]  {
    print(true) // Always true.
}

Hashable has hashValue which should be able to make these values unique, however, hashValue matches for values that are the same. Is there a way that I can extend Hashable so that every element conforming to it will get a UUID() assigned and therefore not identical to any others?

Basically, is there a way to get id: UUID on everything that conforms to Hashable

Solution

  • You probably want to do this a slightly different way. Could your array be of Identifiable instead? Then your example could be:

    struct Person: Identifiable, Hashable {
    let id = UUID()
    let name: String
}

    And each instance of Person will have a unique hashValue:

    let people = [Person(name: "Joe"), Person(name: "Joe"), Person(name: "Joe")]
people.map(\.hashValue) // e.g. -> [7672515142881976808, -2470749298227582550, 3252810522385000211]