87 lines
2.4 KiB
C
87 lines
2.4 KiB
C
/************************************************************************
|
|
** **
|
|
** The YapTab/YapOr/OPTYap systems **
|
|
** **
|
|
** YapTab extends the Yap Prolog engine to support sequential tabling **
|
|
** YapOr extends the Yap Prolog engine to support or-parallelism **
|
|
** OPTYap extends the Yap Prolog engine to support or-parallel tabling **
|
|
** **
|
|
** **
|
|
** Yap Prolog was developed at University of Porto, Portugal **
|
|
** **
|
|
************************************************************************/
|
|
|
|
#ifdef SCCS
|
|
static char SccsId[] = "%W% %G%";
|
|
#endif /* SCCS */
|
|
|
|
/************************************************************
|
|
|
|
Unification Routines
|
|
|
|
*************************************************************/
|
|
|
|
static inline
|
|
Int bind_variable(Term t0, Term t1)
|
|
{
|
|
tr_fr_ptr TR0 = TR;
|
|
if (Yap_IUnify(t0,t1)) {
|
|
return(TRUE);
|
|
} else {
|
|
while(TR != TR0) {
|
|
CELL *p = (CELL *)TrailTerm(--TR);
|
|
RESET_VARIABLE(p);
|
|
}
|
|
return(FALSE);
|
|
}
|
|
}
|
|
|
|
EXTERN inline
|
|
/*
|
|
Int unify(Term t0, Term t1)
|
|
*/
|
|
Int unify(Term t0, Term t1)
|
|
{
|
|
tr_fr_ptr TR0 = TR;
|
|
if (Yap_IUnify(t0,t1)) {
|
|
return(TRUE);
|
|
} else {
|
|
while(TR != TR0) {
|
|
CELL *p = (CELL *)TrailTerm(--TR);
|
|
RESET_VARIABLE(p);
|
|
}
|
|
return(FALSE);
|
|
}
|
|
}
|
|
|
|
EXTERN inline Int unify_constant(register Term a, register Term cons)
|
|
{
|
|
CELL *pt;
|
|
deref_head(a,unify_cons_unk);
|
|
unify_cons_nonvar:
|
|
{
|
|
if (a == cons) return(TRUE);
|
|
else if (IsApplTerm(a) && IsExtensionFunctor(FunctorOfTerm(a))) {
|
|
Functor fun = FunctorOfTerm(a);
|
|
if (fun == FunctorDouble)
|
|
return(IsFloatTerm(cons) && FloatOfTerm(a) == FloatOfTerm(cons));
|
|
else if (fun == FunctorLongInt) {
|
|
return(IsLongIntTerm(cons) && LongIntOfTerm(a) == LongIntOfTerm(cons));
|
|
#ifdef TERM_EXTENSIONS
|
|
} else if (IsAttachFunc(fun)) {
|
|
return(attas[ExtFromFunctor(fun)].bind_op(SBIND,a,cons));
|
|
#endif /* TERM_EXTENSIONS */
|
|
} else
|
|
return(FALSE);
|
|
/* no other factors are accepted as arguments */
|
|
} else return(FALSE);
|
|
}
|
|
|
|
|
|
deref_body(a,pt,unify_cons_unk,unify_cons_nonvar);
|
|
Bind(pt,cons);
|
|
return(TRUE);
|
|
}
|
|
|
|
|