Module: ObjectSpace (Ruby 2.2.3)

The ObjectSpace module contains a number of routines that interact with the garbage collection facility and allow you to traverse all living objects with an iterator. ObjectSpace also provides support for object finalizers, procs that will be called when a specific object is about to be destroyed by garbage collection. a = "A" b = "B" ObjectSpace.define_finalizer(a, proc {|id| puts "Finalizer one