




















ctob

%   Purpose: Intelligent Backtracking DataBase interpreter.

/*  This code comes from the paper
	An Interpreter of Logic Programs Using Selective Backtracking; 
	Luis Moniz Pereira & Antonio Porto,
	Lisbon University report 3/80 CIUNL July 1980
	presented at the Debrecen Logic Programming Workshop 1980.
    That paper presents two interpreters.  One is for full Prolog
    complete with cuts and so on.  This i








































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































