如何省略方法链的中间部分？
假设我有一个带有 save 方法的类，以及三个使用别名修改它的 mixin，例如
module Callbacks
def save_with_callbacks
callback :before_save
save_without_callbacks
end
end
alias_method_chain :save, :callbacks
end
，与 save_with_transaction 和 save_with_timestamps 类似，混合在按照这个顺序，所以 MyModel#save 调用 save_with_timestamps，后者又调用 save_with_transaction，后者又调用save_with_callbacks，最终调用原始save。
现在假设我想在没有交易的情况下保存。我可以调用 save_without_transaction，但这不会调用代码来设置时间戳。
如何使用时间戳和回调保存模型，但不保存事务？
我可以重新排序 mixins，但我的问题是省略中间部分，而不是具体的事务。如何省略方法链的中间部分？
注意 - 为了简洁起见，我使用了 RoR 的 alias_method_chain，但我的问题一般适用于 ruby
Suppose I have a class with a save method, and three mixins which modify it using aliasing, e.g.
module Callbacks
def save_with_callbacks
callback :before_save
save_without_callbacks
end
end
alias_method_chain :save, :callbacks
end
and similarly for save_with_transaction and save_with_timestamps, mixed in in that order, so MyModel#save calls save_with_timestamps, which calls save_with_transaction, which calls save_with_callbacks, which finally calls the original save.
Now suppose I want to save without a transaction. I can call save_without_transaction, but that doesn't call the code to set the timestamps.
How can I save my model with timestamps and callbacks, but no transaction?
I could reorder the mixins, but my question is about omitting the middle, rather than specifically transactions. How can I omit the middle of a chain of methods?
NOTE - I've used RoR's alias_method_chain for brevity, but my question applies to ruby in general
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无论如何，对我来说，您唯一的选择似乎是提供第二个调用链来进一步处理此功能。我认为你不能用别名来做到这一点；您必须定义一个调用旧方法的新方法，例如：
（顺便说一句，长长的别名链不是会让你的代码非常难以阅读吗？我个人认为我会努力避免它们。）
Your only option seems to be -- to me, anyway -- to provide a second calling chain that handles this functionality further up. I don't think you can do this with aliasing; you're going to have to define a new method that calls the old method, instead - so something like:
(As an aside, aren't long chains of aliases going to make your code very difficult to read? Personally I think I would work hard to avoid them.)