The leading sign of a (sub)expression is stored as +-1 in each node's
value field (parse_factor) and every other function multiplies its
result by it. print, squish, gauss and lerp ignored it, so e.g.
-print(1) evaluated to 1 instead of -1 and -gauss(0) to 0.398942
instead of -0.398942, while -1*print(1) was correct.
Fixes: ticket #9833
Reported-by: Player701
Signed-off-by: Bogdan Lisman <bogdan@pydevsolutions.com>
3d1d546f70