BAP Online Manuals : Library Reference : Library by Name : clause
Previous: claim_processes
Next: clear_mailbox

6.2.20. clause

retrieves information from the database

SYNOPSIS

clause(queens(X),Body)

SYNTAX

clause(Head,Body)

ARGUMENTS

void(Head) (i) functor of head of the database predicates to be retrieved
void(Body) (x) body of the database predicate to be retrieved

DESCRIPTION

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.

ERRORS

asserta( repeat ),
asserta(( repeat:-repeat )),
clause(repeat,Body),
	write(Body),nl,
	fail. 

ERRORS

No runtime errors.

LAYERS

prolog-process, client-server, object

RELATED PREDICATES

asserta , assertz , database , retract , retractall , listing


BAP Online Manuals : Library Reference : Library by Name : clause
Previous: claim_processes
Next: clear_mailbox