The type of element returned by next().
typealias Element = (Sequence1.Element, Sequence2.Element)func next() -> Zip2Sequence<Sequence1, Sequence2>.Iterator.Element? Advances to the next element and returns it, or nil if no next element exists.
import Swift@frozen struct IteratorAn iterator for Zip2Sequence.
@frozen struct Zip2Sequence<Sequence1, Sequence2> where Sequence1 : Sequence, Sequence2 : SequenceA sequence of pairs built out of two underlying sequences.
associatedtype Element where Self.Element == Self.Iterator.ElementA type representing the sequence’s elements.
mutating func next() -> Zip2Sequence<Sequence1, Sequence2>.Iterator.Element? Advances to the next element and returns it, or nil if no next element exists.