From: Pedro Del Gallego <pedro.delgallego@...>
Date: 2007-03-12T07:23:58+09:00
Subject: Metaprogramming and class_eval

Hi

Whats the differents between this three classes. Why the
my_attr_accesor dosent create getters and setter clases.


Thanks in advance

#----------------------------------------------------------------------
#
#----------------------------------------------------------------------

class Class
  def my_attr_accessor( *args )
     args.each do |name|
       self.class.class_eval do
          attr_accessor :"#{name}"
       end
     end
  end
end
=> nil

class MyNewClass
  my_attr_accessor :id, :diagram, :telegram
end
=> [:id, :diagram, :telegram]

class MyClass
  attr_accessor    :id, :diagram, :telegram
end
=> nil

class Another_class
  def initialize
    ["id","diagram","telegram"].each do |name|
       self.class.class_eval do
          attr_accessor :"#{name}"
       end
     end
  end
end
=> nil

mnc = MyNewClass.new
=> #<MyNewClass:0xb7b97d0c>
mc  = MyClass.new
=> #<MyClass:0xb7b950fc>
ac  = Another_class.new
=> #<Another_class:0xb7b82358>

ac.diagram
=> nil
mc.diagram


-- 
-------------------------------------
Pedro Del Gallego

Email              :   pedro.delgallego@gmail.com