回调后在AASM中产生项目

Question

你能在一个:after回调中产生项目吗？当我执行以下代码时，我得到了LocalJumpException

require 'aasm'
class TestClass
  include AASM
  aasm do
    state :created, initial: true
    state :running
    event :run do
      transitions from: :created,
      to: :running,
      after: proc { yield 1 }
    end
  end
end
TestClass.new.run! { |v| puts v }

Answer 1

这是不可能的，因为aasm丢弃了传递给事件调用的代码块，但是嘿，它是ruby。

require 'aasm'
class TestClass
  include AASM
  aasm do
    state :created, initial: true
    state :running
    event :run do
      transitions from: :created,
      to: :running,
      after: -> { @λ_run.call(1) if @λ_run } # invoke the code block if was passed
    end
  end
end
TestClass.prepend(Module.new do
  def run!(*args, &λ)
    @λ_run = λ # store the code block passed to the method
    super
  end
end)
TestClass.new.run! { |v| puts v.inspect }

通过一些元编程，它应该很容易扩展到所有已定义的事件处理程序。