I learned Prolog back in 1997, so it may have existed in the implementations I used back then. Must see if I can find an implementation of HU Prolog from back t

I learned Prolog back in 1997, so it may have existed in the implementations I used back then. Must see if I can find an implementation of HU Prolog from back then. I also used SWI Prolog from back then, and I'd expect that was more up to date. Edit: mention SWI Prolog.