I am getting this error: The flow pattern '(o,o)' does not exist for 'main::heal/2'
The logic goal is to find the modifier that shifts a taxon in the right direction. I was an old Borland TurboProlog user and trying to revive old memory cells.
Turbo: all the predicates are "nondeterm", no matter an argument is IN or OUT
VIP: it need to define determ/nondeterm/procedure... arguments IN/OUT
If you don't define, VIP takes the predicate as procedure with arguments IN.