keep on simplifying modules

pl/boot.yap

@@ -1461,7 +1461,7 @@ bootstrap(F) :-
     !,
     '$yap_strip_module'(M1:MH,M,H),
     ( M == M1 -> B = B0 ; B = M1:B0),
-    error:is_callable(M:H,P).
+    is_callable(M:H,P).
 
 '$check_head_and_body'(MH, M, H, true, P) :-
     '$yap_strip_module'(MH,M,H),

pl/consult.yap

@@ -1418,8 +1418,8 @@ initialization(_G,_OPT) :-
                 stop_low_level_trace.
 
 '$initialization'(G,OPT) :-
-   error:must_be_of_type(callable, G, initialization(G,OPT)),
-    error:must_be_of_type(oneof([after_load, now, restore]),
+    must_be_of_type(callable, G, initialization(G,OPT)),
+    must_be_of_type(oneof([after_load, now, restore]),
                 OPT, initialization(G,OPT)),
    (
 	 OPT == now

pl/newmod.yap

@@ -42,12 +42,16 @@ to other modules; they can, however, be accessed by prefixing the module
 name with the `:/2` operator.
 
 **/
+'$module_dec'(system(N, Ss), Ps) :- !,
+	new_system_module(N),
+    '$mk_system_predicates'( Ss , N ),
+    '$module_dec'(N, Ps).
 '$module_dec'(system(N), Ps) :- !,
 	new_system_module(N),
-	recordz('$system_initialization', prolog:'$mk_system_predicates'( Ps , N ), _),
-    '$current_module'(_,N).
+%    '$mk_system_predicates'( Ps , N ),
+    '$module_dec'(N, Ps).
 '$module_dec'(N, Ps) :-	
-    source_location(F,_Line),
+    source_location(F,_Line),	
     '$nb_getval'( '$user_source_file', F0 , fail),
 	'$add_module_on_file'(N, F, F0, Ps),
 	'$current_module'(_,N).
@@ -55,7 +59,7 @@ name with the `:/2` operator.
 '$mk_system_predicates'( Ps, N ) :-
     lists:member(Name/A , Ps),
     functor(P,Name,A),
-    '$mk_system_predicate'(P, N),
+    '$new_system_predicate'(P, prolog),
     fail.
 '$mk_system_predicates'( _Ps, _N ).
 

pl/protect.yap

@@ -20,11 +20,20 @@
 % This protects all code from further changes
 % and also makes it impossible from some predicates to be seen
 '$protect' :-
-	'$current_predicate'(Name,M,P,_),
+	'$current_predicate'(Name,prolog,P,_),
     M \= user,
     functor(P,Name,Arity),
     '$new_system_predicate'(Name,Arity,M),
     sub_atom(Name,0,1,_, '$'),
+    functor(P,Name,Arity),
+    '$hide_predicate'(P,M),
+    fail.
+'$protect' :-
+    '$system_module'(M),
+	'$current_predicate'(Name,M,P,_),
+    M \= user,
+    functor(P,Name,Arity),
+    '$new_system_predicate'(Name,Arity,M),
     fail.
 '$protect' :-
     current_atom(Name),