Already Initialized Constant Warning

gistfile1.txt

eric@penguin ~ $ pry                                                                                                                                           [16:38:41]
[1] pry(main)> class Foo
[1] pry(main)*   ASDF = 'hellooooo'
[1] pry(main)*   class Bar
[1] pry(main)*     class Baz
[1] pry(main)*       def quux
[1] pry(main)*         ASDF
[1] pry(main)*       end  
[1] pry(main)*     end  
[1] pry(main)*   end  
[1] pry(main)* end  
=> :quux
[2] pry(main)> Foo::Bar::Baz.new.quux
=> "hellooooo"
[3] pry(main)> class Foo
[3] pry(main)*   ASDF = 'high up'
[3] pry(main)*   class Bar
[3] pry(main)*     ASDF = 'low down'
[3] pry(main)*     class Baz
[3] pry(main)*       def quux
[3] pry(main)*         ASDF
[3] pry(main)*       end
[3] pry(main)*     end
[3] pry(main)*   end
[3] pry(main)* end
(pry):13: warning: already initialized constant Foo::ASDF
(pry):2: warning: previous definition of ASDF was here
=> :quux
[4] pry(main)> Foo::Bar::Baz.new.quux
=> "low down"