# Mixin both instance and class methods in Ruby

I have a Ruby class into which I want to include both class and instance methods. Following the pattern described in "Ruby Pattern: Extend through Include", I'm currently using the following:

class SomeObject

include SomeObject::Ability

def self.some_builder_method(params)
# use some_class_method ...
end

end

module SomeObject::Ability

module ClassMethods

def some_class_method(param)
# ...
end

end

def self.included(klass)
klass.extend(ClassMethods)
end

def some_instance_method
# ...
end

end


I'd rather not make two separate modules, one being included and the other being extended, because all the methods in my module logically fit together. On the other hand, this pattern requires me to:

1. Define an additional ClassMethods module.
2. Write a boilerplate self.included method for every module.

Is this the most idiomatic way to approach this?

• AFAIK self.included + .extend(ClassMethods) is pretty much the way to do it. If you're using Rails, you can use ActiveSupport::Concern which handles this kind of thing. – Flambino Mar 9 '13 at 15:29