[PD] data structures - get symbol? -> real-time state

[João Miguel Pais]

another question: some time ago I asked if the same feature as  
select/deselect would be available, without involve changing to edit mode.  
or, any way of detecting a real-time transformation of a float in a DS?

In a DS I have the lenght of a polygon which is related to a float, also  
displayed. if I change the lenght with the mouse (of course, not in edit  
mode), is there a way that the other float gets updated? since it's not  
the same variable (even they're related), is there a way of connecting  
both in real-time?

thanks,

Joao