Self-Adaptive Languages: RAPs [Firby PhD RAPS Programs recover by selecting from functionally redundant methods (define-rap (index(move-to?thing? place)) (succeed (LoCation?thing?place)) (method (context( and (location? thing ?loc) (not(?loc UNKNOWN)) (task-net (to(goto ?loc)((TRUCK-LOCATION ? loc)for tD) (tl(pickup? thing)((tRUCK-HOLDING ?thing)for t2) (TRUCK-HOLDING? thing) for t3)) (t2(goto?place)((TRUCK-LOCATION ?place) for t3)) (t3(putdown? thing)) (method (context (LOCATION? thing UNKNOWN)) (task-net (to(goto WAREHOUSE)) Self-Adaptive languages: RAPS RAPS Exploits contingencies by performing functionally redundant method selection Methods are chosen based on the current situation If a method fails. another is tried instead Tasks do not complete until satisfied Methods can include monitoring subtasks that deal with contingencies and opportunities · Limitations Goals must be explicitly observable Methods selected reactively Method selection may dig itself into a hole Create Languages with planner-like capabilities• RAPS Programs recover by selecting from functionally redundant methods (define-rap (index (move-to ?thing ?place)) (succeed (LOCATION ?thing ?place)) (method (context(and (LOCATION ?thing ?loc) (not (= ?loc UNKNOWN)))) (task-net (t0 (goto ?loc) ((TRUCK-LOCATION ?loc) for t1)) (t1 (pickup ?thing)((TRUCK-HOLDING ?thing) for t2) ((TRUCK-HOLDING ?thing) for t3)) (t2 (goto ?place) ((TRUCK-LOCATION ?place) for t3)) (t3 (putdown ?thing)))) (method (context (LOCATION ?thing UNKNOWN)) (task-net (t0 (goto WAREHOUSE))))) Self-Adaptive Languages: RAPs [Firby PhD] Self-Adaptive languages: RAPS • RAPS Exploits contingencies by performing functionally redundant method selection – Methods are chosen based on the current situation. – If a method fails, another is tried instead. – Tasks do not complete until satisfied. – Methods can include monitoring subtasks that deal with contingencies and opportunities. • Limitations • Goals must be explicitly observable • Methods selected reactively ¾Method selection may dig itself into a hole. Create Languages with planner-like capabilities