gistfile1.rb

module A
  def hi(*list)
    list.each do |l|
      class_eval do
        define_method l do
          puts l
        end
      end
    end
  end
end
 
class B
  extend A
end
 
B.hi(:sam, :toddy)
B.sam # => fails
B.new.sam # => prints "sam"