gistfile1.txt

protocol BulkIterator {
    associatedtype Element
    associatedtype Failure: Error = Never
    mutating func nextSpan(maximumCount: Int) throws(Failure) -> Element
}

protocol Iterable where Iterator.Failure == Failure, Iterator.Element == Element {
    associatedtype Element
    associatedtype Failure: Error = Never
    associatedtype Iterator: BulkIterator
    func makeIterator() -> Iterator
}



public protocol Sequence<Element> {
    associatedtype Element
    associatedtype Iterator: IteratorProtocol where Iterator.Element == Element
    func makeIterator() -> Iterator
}

public protocol IteratorProtocol {
    associatedtype Element
    mutating func next() -> Element?
}

/// Wrapper
protocol _Sequence {
    typealias __Element = Element
    typealias __Failure = Failure
    typealias __Iterator = BulkIterator
}

/// Wrapper
protocol _Iterable {
    typealias _Element = Element
    typealias _Failure = Failure
    typealias _Iterator = BulkIterator
}

/// Array that conforms to both
struct Array<_E, F: Error, _I: BulkIterator, I: IteratorProtocol>: _Sequence, _Iterable
where I.Element == _E {
    typealias _Element = _E
    typealias _Iterator = _I
    typealias _Failure = F
    
    typealias __Element = _Element
    typealias __Iterator = I
    
    // Makes a Sequence.Iterator
    func makeIterator() -> I { fatalError() }
    
    // Makes an Iterable.BulkIterator
    func makeIterator() -> _I { fatalError () }
}