Include ClassMethods in plugins

Rails
1

Why is that in so many plugins I see people using (including
acts_as_taggable by DHH):

init.rb

ActiveRecord::Base.send(:include, ActiveRecord::Acts::SomeModule)

lib/some_module.rb

module ActiveRecord
module Acts
module SomeModule
def self.included(base)
base.extend(ClassMethods)
end

  module ClassMethods
    def acts_as_something
      # code
    end
  end
end

end
end

why go through all that rather than just call:

init.rb

ActiveRecord::Base.extend ActiveRecord::Acts::SomeModule::ClassMethods

and skip the self.included method?

2

wyrosdick wrote:

module SomeModule
end
end

why go through all that rather than just call:

init.rb

ActiveRecord::Base.extend ActiveRecord::Acts::SomeModule::ClassMethods

and skip the self.included method?

I guess the use of self.included paves the way for more complex things
to be done when the module included. It also allows the module to be
included into a single AR model or a class of AR models, rather than
into all of AR itself.

If you definitely want to apply the module to all of AR an even shorter
alternative is:

lib/some_module.rb

class ActiveRecord
def self.acts_as_something
# code
end
end

–
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