struct String.UnicodeScalarView.Iterator An iterator over the Unicode scalars that make up a UnicodeScalarView collection. Inheritance IteratorProtocol View Protocol Hierarchy → Import import Swift Instance Methods mutating func next() Advances to the next element and returns it, or nil if no next element exists. Once nil has been returned, all subsequent calls return nil. Precondition: next() has not been applied to a copy of self since the copy was made. Declaration mutating func next() -> Unicode.Scalar?