Example of complete ticker

ticker_complete.cr

struct Ticker
  getter tick, done
  @tick = Channel(Bool).new
  @done = Channel(Bool).new

  def initialize(tick_s : Int32)
    spawn do
      loop do
        sleep tick_s
        @tick.send true
      end
    end
  end

  def stop!
    @done.send true
  end
end

ticker = Ticker.new(2) # 2 seconds

spawn do
  loop do
    select
    when ticker.tick.receive
      puts "#{Time.now}"
    when ticker.done.receive
      puts "break!!!"
      break
    end
  end
end

sleep 7
ticker.stop!