Prime Number Sequence

PrimeNumber.swift

struct PrimeIterator: IteratorProtocol {
    
    var newValue = 2
    var foundPrimes: [Int] = []
    
    mutating func next() -> Int? {
        var nextPrime = newValue
        while foundPrimes.contains(where: { nextPrime % $0 == 0 }) {
            nextPrime += 1
        }
        newValue = nextPrime
        foundPrimes.append(nextPrime)
        return nextPrime
    }
    
}

struct PrimeSequence: Sequence {
    
    func makeIterator() -> PrimeIterator {
        return PrimeIterator()
    }
    
}