Hi, I've noticed a strange behavior that appears to concern the exists() function. If I run the following code repeatedly (by clicking run in the script editor windows): <hansl> loop i=1..3 matrix not_existing_yet = exists(not_existing_yet) ? \ (not_existing_yet ~ I(2)) : I(2) endloop print not_existing_yet delete not_existing_yet </hansl> ...what happens is that every second time it runs as expected, and every other time it produces the error "symbol 'not_existing_yet' undefined" (re-translated). But this error only happens after two loop iterations (i.e. I see "i = 2" in the output). Fairly recent snapshot on Windows. thanks, sven