# File lib/rye/box.rb, line 612
612:       def instance_exec(*args, &block) # !> method redefined; discarding old instance_exec
613:         mname = "__instance_exec_#{Thread.current.object_id.abs}_#{object_id.abs}"
614:         InstanceExecHelper.module_eval{ define_method(mname, &block) }
615:         begin
616:           ret = send(mname, *args)
617:         ensure
618:           InstanceExecHelper.module_eval{ undef_method(mname) } rescue nil
619:         end
620:         ret
621:       end