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Question

我正在努力了解Ruby的收益率。在Gateway类的self.save方法中，它具有“yield gateway”。我理解当调用yield时，会调用Person＃save中的块，但是'block'在该块中变成了什么？你能用这个代码示例解释一下吗

class Person
  attr_accessor :first_name, :last_name, :ssn
    def save
      Gateway.save do |persist|
       persist.subject = self
       persist.attributes = [:first_name, :last_name, :ssn]
       persist.to = 'http://www.example.com/person'
      end
   end
end


class Gateway
  attr_acessor :subject, :attributes, :to

  def self.save
    gateway = self.new
    yield gateway
    gateway.execute
  end

  def execute
    request = Net::HTTP::Post.new(url.path)
    attribute_hash = attributes.inject({}) do | result, attribute |
        result[attribute.to_s] = subject.send attribute
        result
      end
      request.set_form(attribute_hash)
      Net::HTTP.new(url.host, url.post).start { |http| http.request(request) }
   end

   def url
     URI.parse(to)
   end

end

Answer 1

yield的参数将被解析为块的参数。因此，在您的示例中，gateway的值已分配给块的persist参数。