% UBC CPSC 312
% A small example to illustrate Prolog's tracing.
% Credit: David Poole, Steve Wolfman

:- dynamic blox/0.  % No clauses for blox.

fox :- sox, box.
fox :- nox, brix.
sox :- brix, blox.
box :- nox.
clox :- blox.
nox.
brix :- tix, nox.
brix :- box.
tix :- box.