1%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 2% 3% Output predicates 4% This version of the output predicates enables all output 5% 6 7pdl_write(X) :- write(X). 8pdl_on_write(X) :- write(X). 9pdl_nl :- nl. 10pdl_on_nl :- nl. 11pdl_write_ln(X) :- write_ln(X). 12pdl_writef(X,Y) :- writef(X,Y). 13pdl_tab(X) :- tab(X)