def query(clause, args):
"""Executes a query and presents the answers."""
if args.verbose:
print(formatting.comment("% query ") + "{}".format(clause))
# determine debugger
debugger = None
if args.debug:
debugger = ReportingDebugger()
# determine cache mechanism
cache = {'none': caching.NoCache,
'dict': caching.DictCache}[args.cache]()
# set up prover and execute query
prover = logic.Prover(kb, debugger=debugger, cache=cache)
for a in prover.ask(clause):
print("{}.".format(a))
def retract_clause(clause, args):
if args.verbose:
print(formatting.comment("% retract ") + "{}".format(clause))
kb.retract_clause(clause)
def assert_clause(clause, args):
if args.verbose:
print(formatting.comment("% assert ") + "{}".format(clause))
kb.assert_clause(clause)