Ruby: Is it possible to define a class method in a module?

Question

Say there are three classes: A, B & C. I want each class to have a class method, say self.foo, that has exactly the s

Answer 1

This is basic ruby mixin functionality that makes ruby so special. While extend turns module methods into class methods, include turns module methods into instance methods in the including/extending class or module.

module SomeClassMethods
  def a_class_method
    'I´m a class method'
  end
end

module SomeInstanceMethods
  def an_instance_method
   'I´m an instance method!'
  end
end

class SomeClass
  include SomeInstanceMethods
  extend SomeClassMethods
end

instance = SomeClass.new
instance.an_instance_method => 'I´m an instance method!'

SomeClass.a_class_method => 'I´m a class method'