>>>>> "A" == Andres Salomon <dilinger / voxel.net> writes: A> It seems like it needs to be outside of the class, for some reason. The A> following works: write it like this A> x = Foo.new A> include ObjectSpace A> define_finalizer(x, proc { |a| puts 'outside Foo' }) define_finalizer(x, proc { |a| puts "outside Foo #{x}" }) Guy Decoux