1% ------------------------------------------------
    2% Feb 1999
    3% Author: Brian Ross
    4% Dept. of Computer Science, Brock University
    5%
    6% GP dctg operators 
    7%
    8
    9?- op(480, xfy, ':').   10?- op(470, yfx, '*').   11?- op(470, yfx, '+').   12
   13sre(E) :- write(E),nl