Dynamic dispatch and Method Missing in Ruby

#Examples from 'meta programming in Ruby'
#These methods save you from manually typing out each method for the wrapper class.
#If the data source is updated (new methods) you also don't need to update this wrapper class. 

#Dynamic Dispatch

class Computer
  def initialize(computer_id, data_source)
    @id = computer_id
    @data_source = data_source
    data_source.methods.grep(/^get_(.*)_info$/) { Computer.define_component $1 }
  end
  
  def self.define_component(name) define_method(name) {
    info = @data_source.send "get_#{name}_info", 
    @id price = @data_source.send "get_#{name}_price", 
    @id result = "#{name.capitalize}: #{info} ($#{price})" 
    return "* #{result}" if price >= 100
    result }
  end 
end


#Using Method Missing:

class Computer
  def initialize(computer_id, data_source)
    @id = computer_id
    @data_source = data_source
  end
  def method_missing(name, *args)
    super if !@data_source.respond_to?("get_#{name}_info") 
    info = @data_source.send("get_#{name}_info", args[0]) 
    price = @data_source.send("get_#{name}_price", args[0]) 
    result = "#{name.to_s.capitalize}: #{info} ($#{price})" 
    return "* #{result}" if price >= 100
    result
  end 
end