Use case: To prevent button from being tapped multiple times

Throttler.swift

class Throttler {
  private var workItem: DispatchWorkItem?
  private var previousRun: Date = .distantPast
  private let queue: DispatchQueue
  private let minimumDelay: TimeInterval

  init(minimumDelay: TimeInterval, queue: DispatchQueue = .main) {
      self.minimumDelay = minimumDelay
      self.queue = queue
  }
    
  func throttle(_ block: @escaping () -> Void) {
      workItem?.cancel()

      workItem = DispatchWorkItem() { [weak self] in
          self?.previousRun = Date()
          block()
      }

      let delay = previousRun.timeIntervalSinceNow > minimumDelay ? 0 : minimumDelay
      queue.asyncAfter(deadline: .now() + delay, execute: workItem!)
  }
}