rishi/scryer-prolog
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ENHANCED: avoid pending residual constraints in disentailed reified (div)/2

Browse Source 
This addresses #2083:

    ?- #\0#=0//0 div 2.
       true.
This commit is contained in:
Markus Triska
2023-10-08 11:53:06 +02:00
parent ff63eacf2c
commit 5cce8ddd7d
1 changed files with 7 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
src/lib/clpz.pl
View File

@@ -3521,7 +3521,8 @@ L #\ R :- (L #\/ R) #/\ #\ (L #/\ R).
means that V is an auxiliary variable that was introduced while
parsing a compound expression. a(X,V) means V is auxiliary unless
it is ==/2 X, and a(X,Y,V) means V is auxiliary unless it is ==/2 X
or Y. l(L) means the literal L occurs in the described list.
or Y. l(L) means the literal L occurs in the described list,
and ls(Ls) means the literals Ls occur in the described list.
When a constraint becomes entailed or subexpressions become
undefined, created auxiliary constraints are killed, and the
@@ -3552,8 +3553,11 @@ parse_reified(E, R, D,
m(A^B) => [d(D), p(pexp(A,B,R)), a(A,B,R)],
m(A/B) => [d(D1), p(preified_slash(A,B,D2,R)),
p(reified_and(D1,[],D2,[],D)),a(D2),a(A,B,R)],
m(A div B) => [d(D1),
g(phrase(parse_reified_clpz(((A-(A mod B)) // B), R, D2), Ps)),
ls(Ps),
p(reified_and(D1,[],D2,[],D)),a(D2),a(A,B,R)],
m(A//B) => [skeleton(A,B,D,R,ptzdiv)],
m(A div B) => [skeleton(A,B,D,R,pdiv)],
m(A mod B) => [skeleton(A,B,D,R,pmod)],
m(A rem B) => [skeleton(A,B,D,R,prem)],
% bitwise operations
@@ -3644,6 +3648,7 @@ reified_goal(a(V), _) --> [a(V)].
reified_goal(a(X,V), _) --> [a(X,V)].
reified_goal(a(X,Y,V), _) --> [a(X,Y,V)].
reified_goal(l(L), _) --> [[L]].
reified_goal(ls(Ls), _) --> [seq(Ls)].
parse_init_dcg([], _) --> [].
parse_init_dcg([V|Vs], P) --> [{init_propagator(V, P)}], parse_init_dcg(Vs, P).
@@ -4911,10 +4916,6 @@ run_propagator(ptimes(X,Y,Z), MState) -->
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% X div Y = Z
run_propagator(pdiv(X,Y,Z), MState) -->
{ kill(MState), Z #= (X-(X mod Y)) // Y }.
% X // Y = Z (round towards zero)
run_propagator(ptzdiv(X,Y,Z), MState) -->
( nonvar(X) ->