How to determine if one array contains all elements of another array in Swift?

Question

I have 2 arrays:

var list:Array = [1,2,3,4,5]
var findList:Array = [1,3,5]

I want to determine if list A

Answer 1

As a complement to Sequence.contains(element) handling multiple elements, add this extension:

public extension Sequence where Element : Hashable {
    func contains(_ elements: [Element]) -> Bool {
        return Set(elements).isSubset(of:Set(self))
    }
}

Used:

list.contains(findList)

Since this uses Set/Hashable it performs much better than Equatable alternatives.