retrieves information from the database
void(Head) (i) functor of head of the database predicates to be retrieved
void(Body) (x) body of the database predicate to be retrieved
This is a standard PROLOG built-in predicate. It matches any existing database entry with the Head and Body arguments. Head must be sufficiently initialised so that the name of the predicate can be determined. Facts contained in the database are treated as rules with the dummy body ' true '. Clause() may succeed several times.
asserta( repeat ), asserta(( repeat:-repeat )), clause(repeat,Body), write(Body),nl, fail.
No runtime errors.
prolog-process, client-server, object
asserta , assertz , database , retract , retractall , listing