ruby-on-rails - ruby 中是否有 promise 概念？

Question

我只是想知道，ruby 中是否有链接概念。我想一个接一个地执行一系列异步任务或方法。可能吗？

谢谢，拉维

Answer 1

您可能想要创建一个流程类，例如:

class MyProcess

  PROCESS_STEPS = %w(
    step_one
    step_two
    step_three
  )

  class << self 

    def next_step
      new.next_step
    end

  end # Class Methods

  #======================================================================
  # Instance Methods
  #======================================================================

    def next_step
      PROCESS_STEPS.each do |process_step|
        send(process_step) if send("do_#{process_step}?")
      end
    end

    def step_one
      # execute step one task
    end

    def do_step_one?
      # some logic
    end

    def step_two
      # execute step two task
    end

    def do_step_two?
      # some logic
    end

    def step_three
      # execute step three task
    end

    def do_step_three?
      # some logic
    end

end

你可能会把它放在:

app 
 |- processes
 |   |- my_process.rb

然后，在每个任务结束时，执行如下操作:

MyProcess.next_step