[cells-devel] Lots of instances, callback when particular instance changes

Hello! I have the following class (defmodel switch (component) ((pos :initarg :pos :initform (c-in :off) :accessor switch-position))) and I've created lots of switches in a family and I can find them by name. Is there any elegant way of establishing a dependency between one particular instance of switches and some code? I mean, like a callback function to be called when the value of that switch changes? If I use def-c-output on 'pos', it will get called whenever any of the switch instances sets it. Thanks!