__setobj__

# File lib/weakref.rb, line 68
  def __setobj__(obj)
    @__id = obj.__id__
    __old_status = Thread.critical
    begin
      Thread.critical = true
      unless @@id_rev_map.key?(self)
        ObjectSpace.define_finalizer obj, @@final
        ObjectSpace.define_finalizer self, @@final
      end
      @@id_map[@__id] = [] unless @@id_map[@__id]
    ensure
      Thread.critical = __old_status
    end
    @@id_map[@__id].push self.__id__
    @@id_rev_map[self.__id__] = @__id
  end