>I was actually worried that each instance of my class takes too much space
That's essentially why these fields aren't generally supported by the DOM.
It's a significant amount of overhead for data that generally isn't needed
except during debugging.
Of course storing things as objects makes the overhead significantly worse;
that's one of the reasons we're moving toward DTM. So you probably want a
non-object solution -- some sort of table (a group of arrays, perhaps) that
stores the location info without the overhead of an object per location.
You also want to think about storing only the absolutely essential
information -- maybe only the location of elements. That requires that you
start dealing with sparse arrays, and life gets complicated...
Adding features without impacting speed and storage efficiency is not easy!
