With iOS 14 we can now have three columns to display primary list , supplementary and the detail controller. Prior to iOS 14 we just had two controllers, primary and the secondary controller.

With iOS we can define three controllers which are displayed separated by a sidebar.

i.e Primary controller…

Is implementation of sequence protocol , destructive ? Why and how!

Sequence type is said to provide sequential, iterated access of its elements.

Think of a sequence generator which can be used to create user id’s, from a starting point.

public struct UserIdSequenceGenerator: Sequence {  private var startId: Int  public init(startId: Int){     self.startId = startId  }
extension UserIdSequenceGenerator: IteratorProtocol {


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