support PL_skip_list and PL_unify_bool.

C/c_interface.c

@@ -416,7 +416,7 @@ X_API Term    STD_PROTO(YAP_MkListFromTerms,(Term *,Int));
 X_API Term    STD_PROTO(YAP_MkNewPairTerm,(void));
 X_API Term    STD_PROTO(YAP_HeadOfTerm,(Term));
 X_API Term    STD_PROTO(YAP_TailOfTerm,(Term));
-X_API int     STD_PROTO(YAP_SkipList,(Term *, Term **));
+X_API Int     STD_PROTO(YAP_SkipList,(Term *, Term **));
 X_API Term    STD_PROTO(YAP_MkApplTerm,(Functor,UInt,Term *));
 X_API Term    STD_PROTO(YAP_MkNewApplTerm,(Functor,UInt));
 X_API Functor STD_PROTO(YAP_FunctorOfTerm,(Term));
@@ -1050,14 +1050,15 @@ YAP_TailOfTerm(Term t)
   return (TailOfTerm(t));
 }
 
-X_API int
+X_API Int
 YAP_SkipList(Term *l, Term **tailp)
 {
+  return Yap_SkipList(l, tailp);
   Int length = 0;
   Term *s; /* slow */
   Term v; /* temporary */
 
-  v = Derefa(l);
+  do_derefa(v,l,derefa_unk,derefa_nonvar);
   s = l;
 
   if ( IsPairTerm(*l) )
@@ -1070,7 +1071,8 @@ YAP_SkipList(Term *l, Term **tailp)
       }
       lam++;
       length++;
-      l = RepPair(*l)+1; v = Derefa(l);
+      l = RepPair(*l)+1; 
+      do_derefa(v,l,derefa2_unk,derefa2_nonvar);
     } while ( *l != *s && IsPairTerm(*l) );
   }
   *tailp = l;
@@ -3550,15 +3552,15 @@ YAP_FloatsToList(double *dblp, size_t sz)
   if (!sz)
     return TermNil;
   while (ASP-1024 < H + sz*(2+2+SIZEOF_DOUBLE/SIZEOF_LONG_INT)) {
-    if (dblp > H0 && dblp < H) {
+    if ((CELL *)dblp > H0 && (CELL *)dblp < H) {
       /* we are in trouble */
-      LOCAL_OpenArray =  dblp;
+      LOCAL_OpenArray =  (CELL *)dblp;
     }
     if (!dogc( PASS_REGS1 )) {
       RECOVER_H();
       return 0L;
     }
-    dblp = LOCAL_OpenArray;
+    dblp = (double *)LOCAL_OpenArray;
     LOCAL_OpenArray = NULL;
   }
   t = AbsPair(H);

include/SWI-Prolog.h

@@ -215,6 +215,10 @@ typedef void *PL_engine_t;
 #define PL_CHAR          (38)           /* int */
 #define PL_CODE          (39)           /* int */
 #define PL_BYTE          (40)           /* int */
+					/* PL_skip_list() */
+#define PL_PARTIAL_LIST	 (41)		/* a partial list */
+#define PL_CYCLIC_TERM	 (42)		/* a cyclic list/term */
+#define PL_NOT_A_LIST	 (43)		/* Object is not a list */
 
 #define CVT_ATOM	0x0001
 #define CVT_STRING	0x0002
@@ -502,11 +506,19 @@ extern X_API  int PL_unify_list_chars(term_t, const char *);
 extern X_API  int PL_unify_list_ncodes(term_t, size_t, const char *);
 extern X_API  int PL_unify_nil(term_t);
 extern X_API  int PL_unify_pointer(term_t, void *);
+extern X_API  int PL_unify_bool(term_t, int);
 extern X_API  int PL_unify_string_chars(term_t, const char *);
 extern X_API  int PL_unify_string_nchars(term_t, size_t, const char *);
 extern X_API  int PL_unify_term(term_t,...);
 extern X_API  int PL_unify_chars(term_t, int, size_t, const char *);
 extern X_API  int PL_unify_chars_diff(term_t, term_t, int, size_t, const char *);
+		 /*******************************
+		 *	       LISTS		*
+		 *******************************/
+
+PL_EXPORT(int)		PL_skip_list(term_t list, term_t tail, size_t *len);
+
+
 extern X_API  int PL_unify_wchars(term_t, int, size_t, const pl_wchar_t *);
 extern X_API  int PL_unify_wchars_diff(term_t, term_t, int, size_t, const pl_wchar_t *);
 extern X_API  int PL_chars_to_term(const char *,term_t);

include/YapInterface.h

@@ -193,7 +193,7 @@ extern X_API YAP_Term PROTO(YAP_HeadOfTerm,(YAP_Term));
 extern X_API YAP_Term PROTO(YAP_TailOfTerm,(YAP_Term));
 
 /*    Int  AddressOfTailOfTerm(Term *, Term **)  */
-extern X_API int PROTO(YAP_SkipList,(YAP_Term *, YAP_Term **));
+extern X_API YAP_Int PROTO(YAP_SkipList,(YAP_Term *, YAP_Term **));
 
 /*    Term  TailOfTerm(Term)  */
 extern X_API YAP_Term PROTO(YAP_TermNil,(void));

library/dialect/swi/fli/swi.c

@@ -460,6 +460,13 @@ X_API int PL_get_int64(term_t ts, int64_t *i)
 #endif
 }
 
+X_API int PL_unify_bool(term_t t, int a)
+{
+  CACHE_REGS
+  Term iterm = (a ? MkAtomTerm(AtomTrue) : MkAtomTerm(AtomFalse) );
+  return Yap_unify(Yap_GetFromSlot(t PASS_REGS),iterm);
+}
+
 
 #if USE_GMP
 
@@ -1766,6 +1773,34 @@ X_API int PL_is_list(term_t ts)
   return Yap_IsListTerm(t);
 }
 
+X_API int
+PL_skip_list(term_t list, term_t tail, size_t *len)
+{ 
+  CACHE_REGS
+  Term *l = Yap_AddressFromSlot(list PASS_REGS);
+  Term *t;
+  intptr_t length;
+
+  length = Yap_SkipList(l, &t);
+  if ( len )
+    *len = length;
+  if ( tail )
+  { Term t2 = Yap_GetFromSlot(tail);
+
+    Yap_unify(t2, *t);
+  }
+
+  if ( *t == TermNil )
+    return PL_LIST;
+  else if ( IsVarTerm(*t) )
+    return PL_PARTIAL_LIST;
+  else if ( IsPairTerm(*t) )
+    return PL_CYCLIC_TERM;
+  else
+    return PL_NOT_A_LIST;
+}
+
+
 X_API int PL_is_number(term_t ts)
 {
   CACHE_REGS