I recently came across the work documented here https://pauillac.inria.fr/~haemmerl/gprolog-rh/
Similarly I saw the code for that project which seems to be a fork of the main Gnu Prolog sources. I understand that project is quite old at this point, but I am curious as to why the main GNU Prolog lacks these features which were previously developed. I am interested in attributed variables, and mainly use GNU Prolog for my work. Is there any way to get access to these things from a more current version of GNU Prolog?
