A question on GC and weak referenced tables....

[Lawrie Nichols <lawrien@...>]

Hi all

I've got a problem trying to use weak-referenced tables. While they 
perform as described, it's not quite what I had hoped for. The problem 
is really that entries in such a table (be it weak-keyed or weak-valued) 
remain accessible until the underlying object is marked (or unmarked ??) 
by a GC cycle.

So, my questions are:

1) is it possible to force the GC to just mark an object (or unmark it 
??) without running a full GC cycle ?
2) if the answer to 1) above is yes, then is it possible for table 
keys/values to 'hide' the table entry if their underlying object has 
been marked to die ? Currently, is seems that such tables will only 
remove entries as part of a GC cycle.

Apologies in advance on my ignorance of the Lua GC.

Lawrie