/// A sequence containing the same elements as this sequence, /// but on which some operations, such as `map` and `filter`, are /// implemented lazily. /// /// - SeeAlso: `LazySequenceProtocol`, `LazySequence` public var lazy: LazySequence<LazySequence<Base>> { get } /// Returns a `LazyMapSequence` over this `Sequence`. The elements of /// the result are computed lazily, each time they are read, by /// calling `transform` function on a base element. public func map<U>(_ transform: @escaping (Base.Iterator.Element) -> U) -> LazyMapSequence<Base, U>