http://stackoverflow.com/questions/6571200/pilog-assertion

On Mon, Jul 04, 2011 at 12:26:46AM -0700, Doug Snead wrote: > Consider these five pilog assertions. > > (be do ((Question @P) @S @S) (holds @P @S)) > > (be holds (@A @S) > (restoreSitArg @A @S @F) > (2 cons (-> @F))) > > (be On (3 s0)) > (be On (5 s0)) > > (be restoreSitArg ((On @N) @S (On @N @S))) > > I define some tests. > > (de t_1 () # ok > (? holds On restoreSitArg (holds (On @N) s0)) ) > > (de t_2 () # ? > (? do holds On restoreSitArg (do (Question (On @N)) s0 s0)) ) > > Run the first one. > > (t_1) > 1 (holds (On @N) s0) > 1 (restoreSitArg (On @N) s0 (On @N s0)) > 1 (On 3 s0) > @N=3 > 2 (On 5 s0) > @N=5 > -> NIL > > Ok, in that first test, I asked for solutions to (holds (On @N) s0)), tracing > on. > > Those are solutions I would expect, and they are correct. > > Second test. > > (t_2) > 1 (do (Question (On @N)) s0 s0) > 1 (holds (On @N) s0) > 1 (restoreSitArg (On @N) s0 (On @N s0)) > 1 (On 3 s0) > @N=NIL > 2 (On 5 s0) > @N=NIL > -> NIL > > Now here, (holds (On @N) s0) is also attempted to be proved - because it is a > sub-goal of (do (Question (On @N)) s0 s0). > > My question is, why the difference when (holds (On @N) s0) is proved? > > In one case solutions are found, in the other case it seems to miss the same > solutions to the same goal. > > Cheers, > > Doug > > -- > UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe