From: Artur Merke <am@...>
Date: 2006-10-17T18:55:05+09:00
Subject: metaprogramming surprise?

Here comes some simple meta code

>>>>>>>>>>>>>>>>>>>>>>>>>
class D
  @@e=5
  @@f = 10
  @@g = 20
  class << self
    attr_reader :e
    attr_accessor :g
  end
  def self.f
    @@f
  end

  def show
    print "\nshow @@e=",@@e, " @@f=", @@f, " @@g=",@@g
    print "\nshow self.class.e=", self.class.e
    print "\nshow self.class.f=", self.class.f
    print "\nshow self.class.g=", self.class.g
  end
end

D.g= 40
print "\nD.e= ",D.e
print "\nD.g= ",D.g
print "\nD.f= ",D.f
D.new.show
<<<<<<<<<<<<<<<<<<<<<<<<<<<

here is the result

D.e= nil
D.g= 40
D.f= 10
show @@e=5 @@f=10 @@g=20
show self.class.e=nil
show self.class.f=10
show self.class.g=40

I'would expect
D.e= 5
D.g= 40
D.f= 10
show @@e=5 @@f=10 @@g=40
show self.class.e=nil
show self.class.f=10
show self.class.g=40

so what's wrong with my understanding, that

class D
  @@e=5
  class << self
    attr_reader :e   # <- why this does not refer to @@e
  end
end