Preparing s(CASP) to deal with variant loops.

ATTIC/test_tabling/output01.txt

+[10:25] joaquin@:test_tabling$ scasp -w -i path.pl
+
+Loading files: path.pl
+
+?- p(a,c).
+
+
+Answer 1	(in 2.695 ms):
+{  p(a,c) ,  p(a,b) ,  p(b,c) ,  not p(b,d)  }
+
+[p(a,c)] ? ;
+
+
+fail_pos_loop(variant,p(c,_64705),p(c,_64519))
+
+fail_pos_loop(variant,p(b,_63987),p(b,_63859))
+
+fail_pos_loop(variant,p(c,_64325),p(c,_64219))
+
+fail_pos_loop(variant,p(c,_64753),p(c,_64567))
+
+fail_pos_loop(variant,p(b,_64035),p(b,_63907))
+
+fail_pos_loop(variant,p(b,_63123),p(b,_63075))
+
+fail_pos_loop(variant,p(a,_63026),p(a,_62978))
+
+false
+?- p(a,d).
+
+
+Answer 1	(in 2.816 ms):
+{  p(a,d) ,  p(a,b) ,  p(b,d) ,  not p(b,c)  }
+
+[p(a,d)] ? ;
+
+
+fail_pos_loop(variant,p(d,_64866),p(d,_64680))
+
+fail_pos_loop(variant,p(b,_64148),p(b,_64020))
+
+fail_pos_loop(variant,p(d,_64486),p(d,_64380))
+
+fail_pos_loop(variant,p(d,_64914),p(d,_64728))
+
+fail_pos_loop(variant,p(b,_64196),p(b,_64068))
+
+fail_pos_loop(variant,p(b,_63284),p(b,_63236))
+
+fail_pos_loop(variant,p(a,_63187),p(a,_63139))
+
+false
+?- p(a,X).
+
+
+Answer 1	(in 3.077 ms):
+{  p(a,b) ,  p(b,d) ,  not p(b,c)  }
+
+[p(a,b)] ? ;
+
+
+fail_pos_loop(variant,p(d,_67140),p(d,_66954))
+
+fail_pos_loop(variant,p(b,_66422),p(b,_66294))
+
+fail_pos_loop(variant,p(d,_66760),p(d,_66654))
+
+fail_pos_loop(variant,p(d,_67188),p(d,_67002))
+
+fail_pos_loop(variant,p(b,_66470),p(b,_66342))
+
+fail_pos_loop(variant,p(b,_65558),p(b,_65510))
+
+
+Answer 2	(in 6.167 ms):
+{  p(a,b) ,  not p(b,d) ,  p(b,c)  }
+
+[p(a,b)] ? ;
+
+
+fail_pos_loop(variant,p(c,_67276),p(c,_67056))
+
+fail_pos_loop(variant,p(c,_67276),p(c,_67056))
+
+fail_pos_loop(variant,p(b,_66487),p(b,_66435))
+
+fail_pos_loop(variant,p(c,_66432),p(c,_66326))
+
+fail_pos_loop(variant,p(b,_66174),p(b,_66126))
+
+fail_pos_loop(variant,p(a,_63274),p(a,_63111))
+
+false
+?-  
\ No newline at end of file

ATTIC/test_tabling/p.pl

+p(X) :- p(X).
+
+q(X):- X=1, not p(X).
+
+

ATTIC/test_tabling/path.pl

+p(a,b).
+p(b,c) :- not p(b,d).
+p(b,d) :- not p(b,c).
+
+p(X,Y) :-
+    p(X,Z),
+    p(Z,Y).
+
+
+?- p(a,d).
\ No newline at end of file

ATTIC/test_tabling/pq.pl

+p(X) :- not q(X).
+q(X) :- not p(X).
+
+p(1).
+
+?-  q(X).

ATTIC/test_tabling/prop.pl

+s(X) :- s(X).
+s(1).
+
+?-  not s(X).
+
+

examples/benchmark_EventCalculus/sCASP-clingo/scripts/go_light

@@ -24,7 +24,7 @@ echo -e '\n\n*************\t s(CASP): ?- holdsAt(light_red,6.99) \n'
 time scasp -n0  ../light/bec_light_01.pl ../light/bec_query02.pl 
 
 echo -e '\n\n*************\t s(CASP): ?- holdsAt(light_red,6.999) \n'
-time scasp -n0  ../light/bec_light_01.plb ../light/ec_query03.pl 
+time scasp -n0  ../light/bec_light_01.pl ../light/bec_query03.pl 
 
 echo -e '\n\n*************\t s(CASP): ?- holdsAt(light_red,T) \n'
 time scasp -n0  ../light/bec_light_01.pl ../light/bec_query0x.pl 

src/scasp.pl

@@ -638,7 +638,7 @@ type_loop_(Goal, Iv, N, [_S|Ss], Type) :-
     type_loop_(Goal, NewIv, N, Ss, Type).
 
 type_loop_(Goal, 0, 0, [S|_],fail_pos(S)) :-  \+ \+ Goal == S.
-type_loop_(Goal, 0, 0, [S|_],fail_pos(S)) :-  \+ \+ variant(Goal, S).
+type_loop_(Goal, 0, 0, [S|_],fail_pos(S)) :-  \+ \+ variant(Goal, S), if_user_option(warning,format("\nWARNING: Failing in a positive loop due to a variant call (tabling required).\n\tCurrent call:\t~p\n\tPrevious call:\t~p\n",[Goal,S])).
 %type_loop_(Goal, 0, 0, [S|_],fail_pos(S)) :-  \+ \+ Goal = S.
 type_loop_(Goal, 0, 0, [S|_],pos(S)) :-  \+ \+ Goal = S.
 
@@ -646,7 +646,8 @@ type_loop_(Goal, 0, 0, [S|_],pos(S)) :-  \+ \+ Goal = S.
 % It should be solved using tabling !!
 %% type_loop_(not(Goal), 0, N, [not(S)|_],fail_pos(S)) :- Goal == S, N > 0, 0 is mod(N, 2).
 
-type_loop_(not(Goal), 0, N, [not(S)|_],even) :- Goal == S, N > 0, 1 is mod(N, 2).
+type_loop_(not(Goal), 0, _N, [not(S)|_],even) :- \+ \+ Goal == S. %% redundant, for debugging proposals
+type_loop_(not(Goal), 0, _N, [not(S)|_],even) :- Goal = S. 
 type_loop_(Goal, 0, N, [S|_],even) :- Goal \= not(_), Goal == S, N > 0, 0 is mod(N, 2).
 
 type_loop_(Goal, 0, N, [S|Ss],Type) :-

src/scasp_io.pl

@@ -333,6 +333,8 @@ set_user_option(Option) :- atom_chars(Option,['-','s'|Ns]),number_chars(N,Ns),se
 set_user_option(Option) :- atom_chars(Option,['-','n'|Ns]),number_chars(N,Ns),set(answers,N).
 set_user_option('-v') :- set(check_calls, on).
 set_user_option('--verbose') :- set(check_calls, on).
+set_user_option('-w') :- set(warning, on).
+set_user_option('--warning') :- set(warning, on).
 set_user_option('-j') :- set(print_all, on).
 set_user_option('-j0') :- set(print_all, on).
 set_user_option('--justification') :- set(print_all, on).
@@ -365,6 +367,7 @@ help :-
     display('  -a, --auto            Run in automatic mode (no user interaction).\n'),
     display('  -sN, -nN              Compute N answer sets, where N >= 0. 0 for all.\n'),
     display('  -v, --verbose         Enable verbose progress messages.\n'),
+    display('  -w, --warning         Enable warning messages (failing in variant loops).\n'),
     display('  -j, --justification   Print proof tree for each solution.\n'),
     display('  -d0                   Print the program translated (with duals and nmr_check).\n'),
     display('\n'),