rails macro如何定义？where to define macros in Rails?

http://stackoverflow.com/questions/926489/rails-macro-style-functions

如何定义rails macro? 上面的文章描述的很全面了。 对于controller使用的，就定义在application controller中。对于model会使用的，就reopen activerecord::base

For models, you want to reopen ActiveRecord::Base:

module ActiveRecord
  class Base
    def self.acts_as_super_awesome
      do_more_awesome_stuff
    end
  end
end

I personally would put that in a file in config/initializers so that it gets loaded once, and so that I know where to look for it always.

Then you can access it in models like so:

class MySuperAwesomeModel < ActiveRecord::Base
  acts_as_super_awesome
end