struct GeneratorOfOne<T> A generator that produces one or fewer instances of T. Inheritance GeneratorType, SequenceType, _SequenceType, _Sequence_Type View Protocol Hierarchy → Associated Types Generator = GeneratorOfOne<T> Type alias inferred. Element = Generator.Element Type alias inferred. Import import Swift Initializers init(_:) Construct an instance that generates element!, or an empty sequence if element == nil. Declaration init(_ element: T?) Instance Methods func generate() GeneratorOfOne is also a SequenceType, so it generates a copy of itself Declaration func generate() -> GeneratorOfOne<T> mutating func next() Advance to the next element and return it, or nil if no next element exists. Requires: next() has not been applied to a copy of self since the copy was made, and no preceding call to self.next() has returned nil. Declaration mutating func next() -> T?