From 3bf897c50313356ae3a499a3fadb62e1f265af42 Mon Sep 17 00:00:00 2001
From: Vitor Santos Costa <vsc@dcc.fc.up.pt>
Date: Tue, 3 Jul 2018 12:42:33 +0100
Subject: [PATCH] more

---
 C/errors.c                    | 9 ++++++---
 CXX/yapt.hh                   | 2 +-
 H/YapGFlagInfo.h              | 6 ++++++
 packages/myddas/pl/myddas.ypp | 1 +
 pl/imports.yap                | 3 +++
 5 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/C/errors.c b/C/errors.c
index ca856b98c..3abd55edb 100755
--- a/C/errors.c
+++ b/C/errors.c
@@ -95,8 +95,8 @@ static bool setErr(const char *q, yap_error_descriptor_t *i, Term t) {
   }
 
 #define query_key_s(k, ks, q, i)     \
-  if (strcmp(ks, q) == 0) {                                                    \
-  return MkAtomTerm(Yap_LookupAtom(i->k)); }
+  if (strcmp(ks, q) == 0 && i->k) {                                                    \
+  return MkAtomTerm(Yap_LookupAtom(i->k)); } else {return TermNil;}
 
 #define query_key_t(k, ks, q, i)     \
   if (strcmp(ks, q) == 0) {                                                    \
@@ -986,8 +986,11 @@ static Int reset_exception(USES_REGS1) { return Yap_ResetException(worker_id); }
 Term MkErrorTerm(yap_error_descriptor_t *t) {
   if (t->errorClass == EVENT)
     return t->errorRawTerm;
+  Term tc = t->culprit ? Yap_BufferToTerm(t->culprit, TermNil) : TermNil;
+  if (tc == 0)
+    tc = MkAtomTerm(Yap_LookupAtom(t->culprit));
   return mkerrort(t->errorNo,
-                  t->culprit ? Yap_BufferToTerm(t->culprit, TermNil) : TermNil,
+                  tc,
                   err2list(t));
 }
 
diff --git a/CXX/yapt.hh b/CXX/yapt.hh
index c56562c8c..d841e9cbc 100644
--- a/CXX/yapt.hh
+++ b/CXX/yapt.hh
@@ -117,7 +117,7 @@ public:
   /// numbervars ( int start, bool process=false )
   intptr_t numberVars(intptr_t start, bool skip_singletons = false);
   inline Term term() {
-    return gt();
+    return Deref(gt());
   } /// from YAPTerm to Term (internal YAP representation)
     YAPTerm arg(int i) {
         BACKUP_MACHINE_REGS();
diff --git a/H/YapGFlagInfo.h b/H/YapGFlagInfo.h
index 4633ab29a..0e626dd11 100644
--- a/H/YapGFlagInfo.h
+++ b/H/YapGFlagInfo.h
@@ -159,6 +159,12 @@ opportunity. Initial value is 10,000. May be changed. A value of 0
              NULL),
     YAP_FLAG(DEBUGGER_SHOW_CONTEXT_FLAG, "debugger_show_context", true,
              booleanFlag, "false", NULL),
+    YAP_FLAG(DEFAULT_PARENT_MODULE_FLAG, "default_parent_module", true, isatom, "user", NULL),
+    /**<
+     * A module to be inherited by all other modules. Default is user  that reexports prolog.
+     *
+     * Set it to `prolog` for SICStus Prolog like resolution, to `user` for SWI-like.
+     */
     YAP_FLAG(DIALECT_FLAG, "dialect", false, ro, "yap", NULL),
     /**<
 
diff --git a/packages/myddas/pl/myddas.ypp b/packages/myddas/pl/myddas.ypp
index 991bfff14..0cd260b4d 100644
--- a/packages/myddas/pl/myddas.ypp
+++ b/packages/myddas/pl/myddas.ypp
@@ -181,6 +181,7 @@
       member/2
 	      ]).
 
+:- set(verbose,silent).
 
 
 
diff --git a/pl/imports.yap b/pl/imports.yap
index fea7ba8d0..46dc2a7f6 100644
--- a/pl/imports.yap
+++ b/pl/imports.yap
@@ -38,6 +38,9 @@
 '$get_undefined_predicates'(G, ImportingMod, G0, ExportingMod) :-
 	'$parent_module'(ImportingMod,ExportingModI),
 	'$continue_imported'(ExportingMod, ExportingModI, G0, G).
+'$get_undefined_predicates'(G, ImportingMod, G0, ExportingMod) :-
+	yap_flag(default_parent_module,ExportingModI),
+	'$continue_imported'(ExportingMod, ExportingModI, G0, G).
 
 '$get_undefined_pred'(G, ImportingMod, G0, ExportingMod) :-
     '$get_undefined_predicates'(G, ImportingMod, G0, ExportingMod),