new singleton class relationship

[Ara.T.Howard]

am i the only one who finds this confusing?

harp:~/build/ruby > cat a.rb
class Class
def singleton_class; class << self; self; end; end
end
class Parent
end
class Child < Parent
end

puts "Child < Parent #=> #{ (Child < Parent).inspect }"
puts "Parent.ancestors #=> #{ Parent.ancestors.inspect }"
puts "Child.ancestors #=> #{ Child.ancestors.inspect }"
puts

puts "Child.singleton_class < Parent.singleton_class #=> #{ (Child.singleton_class < Parent.singleton_class).inspect }"
puts "Parent.singleton_class.ancestors #=> #{ Parent.singleton_class.ancestors.inspect }"
puts "Child.singleton_class.ancestors #=> #{ Child.singleton_class.ancestors.inspect }"
puts


harp:~/build/ruby > ruby --version
ruby 1.8.3 (2005-05-16) [i686-linux]


harp:~/build/ruby > ruby a.rb
Child < Parent #=> true
Parent.ancestors #=> [Parent, Object, Kernel]
Child.ancestors #=> [Child, Parent, Object, Kernel]

Child.singleton_class < Parent.singleton_class #=> nil
Parent.singleton_class.ancestors #=> [Class, Module, Object, Kernel]
Child.singleton_class.ancestors #=> [Class, Module, Object, Kernel]


harp:~/build/ruby > ./ruby --version
ruby 1.9.0 (2005-05-16) [i686-linux]


harp:~/build/ruby > ./ruby a.rb
Child < Parent #=> true
Parent.ancestors #=> [Parent, Object, Kernel]
Child.ancestors #=> [Child, Parent, Object, Kernel]

Child.singleton_class < Parent.singleton_class #=> true
Parent.singleton_class.ancestors #=> [Class, Module, Object, Kernel]
Child.singleton_class.ancestors #=> [Class, Module, Object, Kernel]

so - how can 'Child < Parent #=> true' when they have no ancestors in common?
note that i think it __should__ be true - but shouldn't there be at least one
common ancestor then? it seems like Parent's singleton class should show up
in Child.singleton_class.ancestors doesn't it?

cheers.

-a
--
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[Christoph]

so - how can 'Child < Parent #=> true' when they have no ancestors in
common?
note that i think it __should__ be true - but shouldn't there be at
least one
common ancestor then? it seems like Parent's singleton class should
show up
in Child.singleton_class.ancestors doesn't it?

Ancestors apparently ignores singleton ancestors -
so this seems kind of alright to me.

/Christoph