this happens to me again and again: the amount of free memory declines
as the hours pass. eventually i have to restart the system (usually
after a day or two). i think this is because i work with large data
structures, and the top-level definitions accumulate. what i need is
a way to get at the list of symbols defined. i see ,bound? but what i
need is something that returns a list of everything bound, so i can
identify the largest offenders.