diff --git a/changes-5.1.html b/changes-5.1.html
index b310e5dcb..289e6c8a0 100644
--- a/changes-5.1.html
+++ b/changes-5.1.html
@@ -16,6 +16,7 @@
 
 <h2>Yap-5.1.2:</h2>
 <ul>
+<li> NEW: make debugger more like standard debuggers (obs from Miguel Filgueiras).</li> 
 <li> NEW: glist_void_varx was broken (obs from Marius Filip).</li> 
 <li> NEW: unify_with_occurs_check/2 was broken with extensions (obs from Aline Paes).</li> 
 <li> NEW: stack_dump/0 from Trevor.</li> 
diff --git a/pl/boot.yap b/pl/boot.yap
index afe13cae6..68a89d786 100644
--- a/pl/boot.yap
+++ b/pl/boot.yap
@@ -732,7 +732,7 @@ not(G) :-    \+ '$execute'(G).
 	).
 '$call'(\+ X, _CP, _G0, M) :- !,
 	\+ '$execute'(M:X).
-'$call'(not(X), _CP, _G0, _M) :- !,
+'$call'(not(X), _CP, _G0, M) :- !,
 	\+ '$execute'(M:X).
 '$call'(!, CP, _,_) :- !,
 	'$$cut_by'(CP).
@@ -761,7 +761,7 @@ not(G) :-    \+ '$execute'(G).
 
 '$check_callable'(V,G) :- var(V), !,
 	'$do_error'(instantiation_error,G).
-'$check_callable'(M:G1,G) :- var(M), !,
+'$check_callable'(M:_G1,G) :- var(M), !,
 	'$do_error'(instantiation_error,G).
 '$check_callable'(_:G1,G) :- !,
 	'$check_callable'(G1,G).
@@ -928,14 +928,14 @@ bootstrap(F) :-
 	'$dir_separator'(D), 
 	atom_codes(A,[D]),
 	user:library_directory(Dir),
-	'$extend_path'(Dir, A, File, NFile, Goal),
+	'$extend_path'(Dir, A, File, NFile, compile(library(File))),
 	'$search_in_path'(NFile, NewFile), !.
 '$find_in_path'(S,NewFile, _) :-
 	S =.. [Name,File], !,
 	'$dir_separator'(D),
 	atom_codes(A,[D]),
 	user:file_search_path(Name, Dir),
-	'$extend_path'(Dir, A, File, NFile, Goal),
+	'$extend_path'(Dir, A, File, NFile, compile(S)),
 	'$search_in_path'(NFile, NewFile), !.
 '$find_in_path'(File,NewFile,_) :- atom(File), !,
 	'$search_in_path'(File,NewFile),!.
diff --git a/pl/consult.yap b/pl/consult.yap
index 6cc220e4f..49fe5e1d8 100644
--- a/pl/consult.yap
+++ b/pl/consult.yap
@@ -50,7 +50,7 @@ load_files(Files,Opts) :-
 '$process_lf_opts'([Opt|Opts],Silent,InfLevel,Expand,Changed,CompilationMode,Imports,Stream,Encoding,SkipUnixComments,Reconsult,Files,Call) :-
 	'$process_lf_opt'(Opt,Silent,InfLevel,Expand,Changed,CompilationMode,Imports,Stream,Encoding,SkipUnixComments,Reconsult,Files,Call), !, 
 	'$process_lf_opts'(Opts,Silent,InfLevel,Expand,Changed,CompilationMode,Imports,Stream,Encoding,SkipUnixComments,Reconsult,Files,Call).
-'$process_lf_opts'([Opt|Opts],_,_,_,_,_,_,_,_,_,_,_,Call) :-
+'$process_lf_opts'([Opt|_],_,_,_,_,_,_,_,_,_,_,_,Call) :-
 	'$do_error'(domain_error(unimplemented_option,Opt),Call).
 
 '$process_lf_opt'(autoload(true),_,InfLevel,_,_,_,_,_,_,_,_,_,_) :-
@@ -70,7 +70,7 @@ load_files(Files,Opts) :-
 	( var(Encoding) ->
 	    '$do_error'(instantiation_error,Call)
 	;
-	    '$valid_encoding'(Enc, EncCode) ->
+	    '$valid_encoding'(Encoding, EncCode) ->
 	    true
 	;	
 	    '$do_error'(domain_error(io_mode,encoding(Encoding)),Call)
@@ -81,11 +81,11 @@ load_files(Files,Opts) :-
 '$process_lf_opt'(if(changed),_,_,_,changed,_,_,_,_,_,_,_,_).
 '$process_lf_opt'(if(true),_,_,_,true,_,_,_,_,_,_,_,_).
 '$process_lf_opt'(if(not_loaded),_,_,_,not_loaded,_,_,_,_,_,_,_,_).
-'$process_lf_opt'(imports(all),_,_,_,_,_,_,_,_,_,_,_).
+'$process_lf_opt'(imports(all),_,_,_,_,_,_,_,_,_,_,_,_).
 '$process_lf_opt'(imports(Imports),_,_,_,_,_,Imports,_,_,_,_,_,_).
 '$process_lf_opt'(qcompile(true),_,_,_,_,true,_,_,_,_,_,_,Call) :-
 	'$do_error'(domain_error(unimplemented_option,qcompile),Call).
-'$process_lf_opt'(qcompile(false),_,_,_,_,false,_,_,_,_,_,_).
+'$process_lf_opt'(qcompile(false),_,_,_,_,false,_,_,_,_,_,_,_).
 '$process_lf_opt'(silent(true),Silent,silent,_,_,_,_,_,_,_,_,_,_) :-
 	( get_value('$lf_verbose',Silent) -> true ;  Silent = informational),
 	set_value('$lf_verbose',silent).
@@ -93,7 +93,7 @@ load_files(Files,Opts) :-
 '$process_lf_opt'(silent(false),_,_,_,_,_,_,_,_,_,_,_,_).
 '$process_lf_opt'(consult(reconsult),_,_,_,_,_,_,_,_,_,reconsult,_,_).
 '$process_lf_opt'(consult(consult),_,_,_,_,_,_,_,_,_,consult,_,_).
-'$process_lf_opt'(stream(Stream),_,_,_,_,_,_,Stream,_,_,_,Files,_) :-
+'$process_lf_opt'(stream(Stream),_,_,_,_,_,_,Stream,_,_,_,Files,Call) :-
 /*	( '$stream'(Stream) -> true ;  '$do_error'(domain_error(stream,Stream),Call) ), */
 	( atom(Files) -> true ;  '$do_error'(type_error(atom,Files),Call) ).
 
@@ -116,13 +116,13 @@ load_files(Files,Opts) :-
 '$lf'([F|Fs], Mod,Call,InfLevel,Expand,Changed,CompilationMode,Imports,Stream,Encoding,SkipUnixComments,Reconsult,UseModule) :- !,
 	'$lf'(F,Mod,Call,InfLevel,Expand,Changed,CompilationMode,Imports,Stream,Encoding,SkipUnixComments,Reconsult,_),
 	'$lf'(Fs, Mod,Call,InfLevel,Expand,Changed,CompilationMode,Imports,Stream,Encoding,SkipUnixComments,Reconsult,UseModule).
-'$lf'(X, Mod, Call,InfLevel,_,Changed,CompilationMode,Imports,Stream,_,Reconsult,SkipUnixComments,UseModule) :-
+'$lf'(_, Mod, _,InfLevel,_,_,CompilationMode,Imports,Stream,_,Reconsult,SkipUnixComments,UseModule) :-
         nonvar(Stream), !,
-	'$do_lf'(X, Mod, Stream, InfLevel,CompilationMode,Imports,SkipUnixComments,Reconsult,UseModule).
-'$lf'(user, Mod, Call,InfLevel,_,Changed,CompilationMode,Imports,_,_,SkipUnixComments,Reconsult,UseModule) :- !,
-	'$do_lf'(user_input, Mod, user_input, InfLevel, CompilationMode,Imports,SkipUnixComments,Reconsult,UseModule).
-'$lf'(user_input, Mod, Call,InfLevel,_,Changed,CompilationMode,Imports,_,_,SkipUnixComments,Reconsult,UseModule) :- !,
-	'$do_lf'(user_input, Mod, user_input, InfLevel, CompilationMode,Imports,SkipUnixComments,Reconsult,UseModule).
+	'$do_lf'(Mod, Stream, InfLevel,CompilationMode,Imports,SkipUnixComments,Reconsult,UseModule).
+'$lf'(user, Mod, _,InfLevel,_,_,CompilationMode,Imports,_,_,SkipUnixComments,Reconsult,UseModule) :- !,
+	'$do_lf'(Mod, user_input, InfLevel, CompilationMode,Imports,SkipUnixComments,Reconsult,UseModule).
+'$lf'(user_input, Mod, _,InfLevel,_,_,CompilationMode,Imports,_,_,SkipUnixComments,Reconsult,UseModule) :- !,
+	'$do_lf'(Mod, user_input, InfLevel, CompilationMode,Imports,SkipUnixComments,Reconsult,UseModule).
 '$lf'(X, Mod, Call, InfLevel,_,Changed,CompilationMode,Imports,_,Enc,SkipUnixComments,Reconsult,UseModule) :-
 	'$find_in_path'(X, Y, Call),
 	'$open'(Y, '$csult', Stream, 0, Enc), !,
@@ -139,8 +139,8 @@ load_files(Files,Opts) :-
 	'$file_loaded'(Stream, Mod, Imports), !.
 '$start_lf'(_, Mod, Stream, _, _, Imports, changed, _, _, _) :-
 	'$file_unchanged'(Stream, Mod, Imports), !.
-'$start_lf'(X, Mod, Stream, InfLevel, CompilationMode, Imports, _, SkipUnixComments, Reconsult, UseModule) :-
-	'$do_lf'(X, Mod, Stream, InfLevel, CompilationMode, Imports, SkipUnixComments, Reconsult, UseModule).
+'$start_lf'(_, Mod, Stream, InfLevel, CompilationMode, Imports, _, SkipUnixComments, Reconsult, UseModule) :-
+	'$do_lf'(Mod, Stream, InfLevel, CompilationMode, Imports, SkipUnixComments, Reconsult, UseModule).
 
 '$close_lf'(Silent) :- 
 	nonvar(Silent), !,
@@ -169,7 +169,7 @@ consult(Fs) :-
 	'$access_yap_flags'(8, 2), % SICStus Prolog compatibility
 	!,
 	'$load_files'(Module:Fs,[],Fs).
-'$consult'(Fs, Module) :- var(V), !,
+'$consult'(Fs, Module) :-
 	'$load_files'(Module:Fs,[consult(consult)],Fs).
 
 reconsult(Fs) :-
@@ -184,7 +184,7 @@ use_module(F,Is) :-
 use_module(M,F,Is) :-
 	'$use_module'(M,F,Is).
 
-'$use_module'(U,F,Is) :- nonvar(U), U = user, !,
+'$use_module'(U,_F,Is) :- nonvar(U), U = user, !,
 	'$import_to_current_module'(user_input, user, Is).
 '$use_module'(M,F,Is) :- nonvar(M), !,
 	recorded('$module','$module'(F1,M,_),_),
@@ -199,10 +199,10 @@ use_module(M,F,Is) :-
 '$csult'([-F|L], M) :- !, '$load_files'(M:F, [],[-M:F]), '$csult'(L, M).
 '$csult'([F|L], M) :- '$consult'(F, M), '$csult'(L, M).
 
-'$do_lf'(F, ContextModule, Stream, InfLevel, _, Imports, SkipUnixComments, Reconsult, UseModule) :-
+'$do_lf'(ContextModule, Stream, InfLevel, _, Imports, SkipUnixComments, Reconsult, UseModule) :-
 	nb_getval('$system_mode', OldMode),
         ( OldMode == off -> '$enter_system_mode' ; true ),
-	'$record_loaded'(Stream, M),
+	'$record_loaded'(Stream, ContextModule),
 	'$current_module'(OldModule,ContextModule),
 	getcwd(OldD),
 	get_value('$consulting_file',OldF),
@@ -377,7 +377,7 @@ prolog_load_context(source, FileName) :-
 prolog_load_context(stream, Stream) :- 
 	'$fetch_stream_alias'(Stream,'$loop_stream').
 prolog_load_context(term_position, Position) :- 
-	'$fetch_stream_alias'(Stream,'$loop_stream').
+	'$fetch_stream_alias'(Stream,'$loop_stream'),
 	stream_position(Stream, Position).
 
 
@@ -389,11 +389,11 @@ prolog_load_context(term_position, Position) :-
 
 '$ensure_file_loaded'(F, M, Imports) :-
 	recorded('$module','$module'(F1,NM,P),_),
-	recorded('$lf_loaded','$lf_loaded'(F1,_,Age),R),
+	recorded('$lf_loaded','$lf_loaded'(F1,_,_),_),
 	'$same_file'(F1,F), !,
 	'$use_preds'(Imports,P, NM, M).
 '$ensure_file_loaded'(F, M, _) :-
-	recorded('$lf_loaded','$lf_loaded'(F1,M,Age),R),
+	recorded('$lf_loaded','$lf_loaded'(F1,M,_),_),
 	'$same_file'(F1,F), !.
 	
 
diff --git a/pl/corout.yap b/pl/corout.yap
index a81f00829..4919fd2f9 100644
--- a/pl/corout.yap
+++ b/pl/corout.yap
@@ -522,7 +522,7 @@ frozen(V, LG) :-
 	'$purge_done_goals'(G0, GF).
 '$purge_done_goals'(['$redo_freeze'(Done, _, _)|G0], GF) :- nonvar(Done), !,
 	'$purge_done_goals'(G0, GF).
-'$purge_done_goals'(['$redo_freeze'(Done, _, CallCleanup)|G0], GF) :-
+'$purge_done_goals'(['$redo_freeze'(_Done, _, CallCleanup)|G0], GF) :-
 	nonvar(CallCleanup),
 	CallCleanup = _:'$clean_call'(_), !,
 	'$purge_done_goals'(G0, GF).
diff --git a/pl/debug.yap b/pl/debug.yap
index 6499cfda4..788864d56 100644
--- a/pl/debug.yap
+++ b/pl/debug.yap
@@ -320,7 +320,7 @@ debugging :-
 	L1 is L+1,			/* bump it			*/
 	nb_setval('$spy_gn',L1),	/* and save it globaly		*/
         b_getval('$spy_glist',History),	/* get goal list		*/
-	b_setval('$spy_glist',[info(L,Module,G,Retry,Det)|History]),	/* and update it		*/
+	b_setval('$spy_glist',[info(L,Module,G,_Retry,_Det)|History]),	/* and update it		*/
 	'$loop_spy'(L, G, Module, InControl).	/* set creep on		*/
 
 % we are skipping, so we can just call the goal,
@@ -362,11 +362,13 @@ debugging :-
 '$debug_error'(_).
 
 
-'$loop_fail'(GoalNumber, G, Module, InControl) :-
-    '$system_catch'(('$trace'(fail, G, Module, GoalNumber,_),
-		     fail ),
-		    Module, Event,
-		    '$loop_spy_event'(Event, GoalNumber, G, Module, InControl)).
+% just fail here, don't really need to call debugger, the user knows what he
+% wants to do
+'$loop_fail'(_GoalNumber, _G, _Module, _InControl) :-
+	write(_G),nl,
+	yap_hacks:stack_dump,
+	'$continue_debugging',
+	fail.
 
 % if we are in 
 '$loop_spy2'(GoalNumber, G, Module, InControl, CP) :- 
@@ -375,7 +377,7 @@ debugging :-
 	(
 	/* call port */
 	    '$enter_goal'(GoalNumber, G, Module),
-	    '$spycall'(G, Module, InControl),
+	    '$spycall'(G, Module, InControl, Retry),
 	    (
 	      '$debugger_deterministic_goal'(G) ->
 	      Det=true
@@ -384,6 +386,7 @@ debugging :-
 	    ),
 	/* go execute the predicate	*/
 	    (
+	      Retry = false ->
 	      '$show_trace'(exit,G,Module,GoalNumber,Det),	/* output message at exit	*/
 	       /* exit port */
 	       /* get rid of deterministic computations */
@@ -400,7 +403,6 @@ debugging :-
 	        /* we get here when we want to redo a goal		*/
 		/* redo port */
 	        '$show_trace'(redo,G,Module,GoalNumber,_), /* inform user_error		*/
-	      Retry = true,
 	        '$continue_debugging'(InControl,G,Module),
 	        fail			/* to backtrack to spycalls	*/
 	     )
@@ -439,46 +441,41 @@ debugging :-
       number(StopPoint)
     ->
       StopPoint < GoalNumber
-    ;
-      % skip goals and ports (eg, l).
-      StopPoint == spy(StoPoint)
-    ->
-      \+ '$pred_being_spied'(G, Module), StopPoint < GoalNumber
     ).
 	
 
 % 
-'$spycall'(G, M, _) :-
+'$spycall'(G, M, _, _) :-
 	nb_getval('$debug_run',StopPoint),
 	StopPoint \= off,
 	!,
 	'$execute_nonstop'(G, M).
-'$spycall'(G, M, _) :-
+'$spycall'(G, M, _, _) :-
         '$system_predicate'(G,M),
          \+ '$is_metapredicate'(G,M),
 	 !,
 	'$execute_nonstop'(G, M).
-'$spycall'(G, M, InControl) :-
+'$spycall'(G, M, InControl, InRedo) :-
 	'$flags'(G,M,F,F),
 	F /\ 0x18402000 =\= 0, !, % dynamic procedure, logical semantics, user-C, or source
 	% use the interpreter
 	CP is '$last_choice_pt',
 	'$clause'(G, M, Cl),
-	'$do_spy'(Cl, M, CP, InControl).
-'$spycall'(G, M, InControl) :-
+	( '$do_spy'(Cl, M, CP, InControl) ; InRedo = true ).
+'$spycall'(G, M, InControl, InRedo) :-
 	'$undefined'(G, M), !,
 	'$enter_undefp',
 	(
 	    '$find_undefp_handler'(G,M,Goal,NM)
 	->
-	   '$spycall'(Goal, NM, InControl)
+	   '$spycall'(Goal, NM, InControl, InRedo)
        ).
-'$spycall'(G, M, InControl) :-
+'$spycall'(G, M, InControl, InRedo) :-
 	% I lost control here.
 	CP is '$last_choice_pt',
 	'$static_clause'(G,M,_,R),
 	'$continue_debugging'(InControl, G, M),
-	'$execute_clause'(G, M, R, CP).
+	( '$execute_clause'(G, M, R, CP) ; InRedo = true ).
 
 '$trace'(P,G,Module,L,Deterministic) :-
 	% at this point we are done with leap or skip
@@ -562,7 +559,6 @@ debugging :-
 	halt.
 '$action'(0'f,_,CallId,_,_,_) :- !,		% f		fail
 	'$scan_number'(0'f, CallId, GoalId),
-        nb_setval('$debug,on'),
 	throw('$fail_spy'(GoalId)).
 '$action'(0'h,_,_,_,_,_) :- !,			% h		help
 	'$action_help',
@@ -588,15 +584,15 @@ debugging :-
 	),
 	'$skipeol'(0'd),
 	fail.
-'$action'(0'l,_,CallNumber,_,_,on) :- !,		% l		leap
+'$action'(0'l,_,_,_,_,on) :- !,		% l		leap
 	'$skipeol'(0'l),
 	nb_setval('$debug_run',spy).
-'$action'(0'z,_,CallNumber,_,_,zip) :- !,		% k		zip, fast leap
+'$action'(0'z,_,_,_,_,zip) :- !,		% k		zip, fast leap
 	'$skipeol'(0'z),
 	nb_setval('$debug_run',spy).
 	% skip first call (for current goal),
 	% stop next time.
-'$action'(0'k,_,CallNumber,_,_,zip) :- !,		% k		zip, fast leap
+'$action'(0'k,_,_,_,_,zip) :- !,		% k		zip, fast leap
 	'$skipeol'(0'k),
 	nb_setval('$debug_run',spy).
 	% skip first call (for current goal),
@@ -646,7 +642,7 @@ debugging :-
 '$continue_debugging'(_,G,M) :-
 	'$system_predicate'(G,M), !,
 	'$late_creep'.
-'$continue_debugging'(_,G,M) :-
+'$continue_debugging'(_,_,_) :-
 	'nb_getval'('$debug_run',Zip),
         (Zip == nodebug ; number(Zip) ; Zip = spy(_) ), !.
 '$continue_debugging'(_,_,_) :-
@@ -676,11 +672,11 @@ debugging :-
 '$show_ancestor'(_,_,_,_,Det,HowMany,HowMany) :-
 	nonvar(Det), !.
 % look at retry
-'$show_ancestor'(GoalNumber, M, G, Retry, Det, HowMany, HowMany1) :-
+'$show_ancestor'(GoalNumber, M, G, Retry, _, HowMany, HowMany1) :-
 	nonvar(Retry), !,
 	HowMany1 is HowMany-1,
 	'$trace_msg'(redo, G, M, GoalNumber, _), nl(user_error).
-'$show_ancestor'(GoalNumber, M, G, Retry, Det, HowMany, HowMany1) :-
+'$show_ancestor'(GoalNumber, M, G, _, _, HowMany, HowMany1) :-
 	HowMany1 is HowMany-1,
 	'$trace_msg'(call, G, M, GoalNumber, _), nl(user_error).
 
@@ -831,18 +827,27 @@ debugging :-
 	format(user_error,'      [~d] ~q~n',[Level,G]).
 	
 '$debugger_deterministic_goal'(G) :-
-	yap_hacks:current_choicepoints(CPs),
-	'$debugger_skip_traces'(CPs,CPs1),
-	'$debugger_skip_loop_spy2'(CPs1,[Catch|_]),
+	yap_hacks:current_choicepoints(CPs0),
+%	$cps(CPs0),
+	'$debugger_skip_traces'(CPs0,CPs1),
+	'$debugger_skip_loop_spy2'(CPs1,CPs2),
+	'$debugger_skip_spycall'(CPs2,CPs3),
+	'$debugger_skip_loop_spy2'(CPs3,[Catch|_]),
 	yap_hacks:choicepoint(Catch,_,prolog,'$catch',3,'$catch'(_,'$loop_spy_event'(_,_,G,_,_),_),_).
 
 
 '$cps'([CP|CPs]) :-
-    yap_hacks:choicepoint(CP,_,_,_,_,_,_),
+    yap_hacks:choicepoint(CP,A,B,C,D,E,F),
+    write(A:B:C:D:E:F),nl,
     '$cps'(CPs).
 '$cps'([]).
 
 
+'$debugger_skip_spycall'([CP|CPs],CPs1) :-
+	yap_hacks:choicepoint(CP,_,prolog,'$spycall',4,(_;_),_), !,
+	'$debugger_skip_spycall'(CPs,CPs1).
+'$debugger_skip_spycall'(CPs,CPs).
+
 '$debugger_skip_traces'([CP|CPs],CPs1) :-
 	yap_hacks:choicepoint(CP,_,prolog,'$trace',4,(_;_),_), !,
 	'$debugger_skip_traces'(CPs,CPs1).
diff --git a/pl/directives.yap b/pl/directives.yap
index 419244ce3..a510b9c22 100644
--- a/pl/directives.yap
+++ b/pl/directives.yap
@@ -65,7 +65,7 @@
 	'$discontiguous'(D,M).
 '$exec_directive'(initialization(D), _, M) :-
 	'$initialization'(M:D).
-'$exec_directive'(encoding(Enc), _, M) :-
+'$exec_directive'(encoding(Enc), _, _) :-
 	'$current_encoding'(Enc).
 '$exec_directive'(parallel, _, _) :-
 	'$parallel'.
@@ -107,7 +107,7 @@
 	'$load_files'(M:F, [if(not_loaded)],use_module(F)).
 '$exec_directive'(use_module(F,Is), _, M) :-
 	'$load_files'(M:F, [if(not_loaded),imports(Is)],use_module(F,Is)).
-'$exec_directive'(use_module(Mod,F,Is), _, M) :-
+'$exec_directive'(use_module(Mod,F,Is), _, _) :-
 	'$use_module'(Mod,F,Is).
 '$exec_directive'(block(BlockSpec), _, _) :-
 	'$block'(BlockSpec).
diff --git a/pl/errors.yap b/pl/errors.yap
index 9ff5f390a..2edad2c33 100644
--- a/pl/errors.yap
+++ b/pl/errors.yap
@@ -11,8 +11,11 @@
 * File:		errors.yap						 *
 * comments:	error messages for YAP					 *
 *									 *
-* Last rev:     $Date: 2006-12-13 16:10:26 $,$Author: vsc $						 *
+* Last rev:     $Date: 2007-01-24 14:20:04 $,$Author: vsc $						 *
 * $Log: not supported by cvs2svn $
+* Revision 1.79  2006/12/13 16:10:26  vsc
+* several debugger and CLP(BN) improvements.
+*
 * Revision 1.78  2006/05/22 16:12:01  tiagosoares
 * MYDDAS: MYDDAS version boot message
 *
@@ -169,7 +172,6 @@
 	'$process_error'(Error, Level),
 	fail.
 '$LoopError'(_, _) :-
-	current_stream(_, write, S),
 	flush_all_streams,
 	fail.
 
@@ -296,7 +298,7 @@ print_message(Level, Mss) :-
 	[M,F,N]).
 '$do_print_message'(breakpoints([])) :- !,
 	format(user_error,'There are no spy-points set.',
-	[M,F,N]).
+	[]).
 '$do_print_message'(breakpoints(L)) :- !,
 	format(user_error,'Spy-points set on:', []),
 	'$print_list_of_preds'(L).
@@ -317,7 +319,7 @@ print_message(Level, Mss) :-
 	[From,Pred,To]).
 '$do_print_message'(leash([])) :- !,
 	format(user_error,'No leashing.',
-	[M,F,N]).
+	[]).
 '$do_print_message'(leash([A|B])) :- !,
 	format(user_error,'Leashing set to ~w.',
 	[[A|B]]).
@@ -378,13 +380,13 @@ print_message(Level, Mss) :-
 	'$close_stack_dump'(PEnvs, PCPs).
 
 '$preprocess_stack'([], _, []).
-'$preprocess_stack'([G|Gs],40, [overflow]) :- !.
+'$preprocess_stack'([_|_],40, [overflow]) :- !.
 '$preprocess_stack'([G|Gs],I, NGs) :-
 	'$pred_for_code'(G,Name,Arity,Mod,Clause),
 	I1 is I+1,
 	'$beautify_stack_goal'(Name,Arity,Mod,Clause,Gs,I1,NGs).
 	
-'$beautify_stack_goal'(Name,Arity,Module,0,Gs,I,NGs) :- !,
+'$beautify_stack_goal'(_,_,_,0,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs,I,NGs).
 '$beautify_stack_goal'(Name,Arity,Module,Clause,Gs,I,NGs) :-
 	functor(G,Name,Arity),
@@ -399,47 +401,47 @@ print_message(Level, Mss) :-
 '$beautify_hidden_goal'('$query',_,_,_,_,_,[]) :- !.
 '$beautify_hidden_goal'('$enter_top_level',_,_,_,_,_,[]) :- !.
 % The user should never know these exist.
-'$beautify_hidden_goal'('$csult',_,prolog,ClNo,Gs,NGs) :- !,
+'$beautify_hidden_goal'('$csult',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$use_module',2,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$use_module',2,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$ensure_loaded',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$ensure_loaded',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$continue_with_command',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$continue_with_command',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$spycall_stdpred',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$spycall_stdpred',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$spycalls',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$spycalls',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$spycall',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$spycall',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$do_spy',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$do_spy',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$spy',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$spy',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$do_creep_execute',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$do_creep_execute',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$creep_execute',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$creep_execute',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$direct_spy',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$direct_spy',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$system_catch',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$system_catch',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$execute_command',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$execute_command',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$process_directive',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$process_directive',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$catch',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$catch',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$loop',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$loop',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$consult',3,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$consult',3,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$reconsult',_,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$reconsult',_,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$undefp',1,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$undefp',1,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
-'$beautify_hidden_goal'('$use_module',2,prolog,ClNo,Gs,I,NGs) :- !,
+'$beautify_hidden_goal'('$use_module',2,prolog,_,Gs,I,NGs) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
 '$beautify_hidden_goal'('$repeat',0,prolog,ClNo,Gs,I,[cl(repeat,0,prolog,ClNo)|NGs]) :- !,
 	'$preprocess_stack'(Gs, I, NGs).
@@ -488,7 +490,7 @@ print_message(Level, Mss) :-
 '$prepare_loc'(Info,Where,Location) :- integer(Where), !,
 	'$pred_for_code'(Where,Name,Arity,Mod,Clause),
 	'$construct_code'(Clause,Name,Arity,Mod,Info,Location).
-'$prepare_loc'(Info,Where,Info).
+'$prepare_loc'(Info,_,Info).
 
 '$print_stack'([]).
 '$print_stack'([overflow]) :- !,
@@ -499,7 +501,7 @@ print_message(Level, Mss) :-
 
 '$show_goal'(-1,Name,Arity,Mod) :- !,
 	format('~n%      ~a:~a/~d at indexing code',[Mod,Name,Arity]).
-'$show_goal'(0,Name,Arity,Mod) :- !.
+'$show_goal'(0,_,_,_) :- !.
 '$show_goal'(I,Name,Arity,Mod) :-
 	format(user_error,'~n%      ~a:~a/~d at clause ~d',[Mod,Name,Arity,I]).
 
@@ -773,7 +775,7 @@ print_message(Level, Mss) :-
 '$output_error_message'(representation_error(max_arity), Where) :-
 	format(user_error,'% REPRESENTATION ERROR- ~w: number too big~n',
 	[Where]).
-'$output_error_message'(syntax_error(G,0,Msg,[],0,0), Where) :- !,
+'$output_error_message'(syntax_error(G,0,Msg,[],0,0), _) :- !,
 	format(user_error,'% SYNTAX ERROR: ~a',[G,Msg]).
 '$output_error_message'(syntax_error(_,_,_,Term,Pos,Start), Where) :-
 	format(user_error,'% ~w ',[Where]),
@@ -885,7 +887,7 @@ print_message(Level, Mss) :-
 	format(user_error,'~n<==== HERE ====>~n', []),
 	'$dump_syntax_error_term'(10,-1,L).
 '$dump_syntax_error_term'(_,_,[]) :- !.
-'$dump_syntax_error_term'(I,J,[T-P|R]) :-
+'$dump_syntax_error_term'(I,J,[T-_P|R]) :-
 	'$dump_error_token'(T),
 	I1 is I-1,
 	J1 is J-1,
diff --git a/pl/threads.yap b/pl/threads.yap
index 0593466ff..5dc824b06 100644
--- a/pl/threads.yap
+++ b/pl/threads.yap
@@ -117,7 +117,7 @@ thread_create(Goal, Id, Options) :-
 	'$thread_option'(Opt, Alias, Stack, Trail, System, Detached, G0),
 	'$thread_options'(Opts, Alias, Stack, Trail, System, Detached, G0).
 
-'$thread_option'(Option, Alias, _, _, _, _, G0) :- var(Option), !,
+'$thread_option'(Option, _, _, _, _, _, G0) :- var(Option), !,
 	'$do_error'(instantiation_error,G0).
 '$thread_option'(stack(Stack), _, Stack, _, _, _, G0) :- !,
 	( \+ integer(Stack) -> '$do_error'(type_error(integer,Stack),G0) ; true ).
@@ -143,9 +143,10 @@ thread_create(Goal, Id, Options) :-
 	recorda('$thread_sizes', [Id|Sizes], _),
 	recorda('$thread_detached', [Id|Detached], _).
 
+% vsc: ?????
 thread_defaults(Defaults) :-
 	nonvar(Defaults), !,
-	'$do_error'(type_error(variable,Id), thread_defaults(Defaults)).
+	'$do_error'(type_error(variable,_Id), thread_defaults(Defaults)).
 thread_defaults([stack(Stack), trail(Trail), system(System), detached(Detached)]) :-
 	recorded('$thread_defaults',[Stack, Trail, System, Detached], _).
 
@@ -192,7 +193,7 @@ thread_set_default(Default) :-
 '$thread_set_default'(stack(Stack), G) :-
 	Stack < 0, !,
 	'$do_error'(domain_error(not_less_than_zero, Stack), G).
-'$thread_set_default'(stack(Stack), G) :- !,
+'$thread_set_default'(stack(Stack), _) :- !,
 	recorded('$thread_defaults', [_, Trail, System, Detached], Ref),
 	erase(Ref),
 	recorda('$thread_defaults', [Stack, Trail, System, Detached], _).
@@ -203,7 +204,7 @@ thread_set_default(Default) :-
 '$thread_set_default'(trail(Trail), G) :-
 	Trail < 0, !,
 	'$do_error'(domain_error(not_less_than_zero, Trail), G).
-'$thread_set_default'(trail(Trail), G) :- !,
+'$thread_set_default'(trail(Trail), _) :- !,
 	recorded('$thread_defaults', [Stack, _, System, Detached], Ref),
 	erase(Ref),
 	recorda('$thread_defaults', [Stack, Trail, System, Detached], _).
@@ -214,7 +215,7 @@ thread_set_default(Default) :-
 '$thread_set_default'(system(System), G0) :-
 	System < 0, !,
 	'$do_error'(domain_error(not_less_than_zero, System), G0).
-'$thread_set_default'(system(System), G) :- !,
+'$thread_set_default'(system(System), _) :- !,
 	recorded('$thread_defaults', [Stack, Trail, _, Detached], Ref),
 	erase(Ref),
 	recorda('$thread_defaults', [Stack, Trail, System, Detached], _).
@@ -222,7 +223,7 @@ thread_set_default(Default) :-
 '$thread_set_default'(detached(Detached), G) :-
 	Detached \== true, Detached \== false, !,
 	'$do_error'(type_error(boolean, Detached), G).
-'$thread_set_default'(detached(Detached), G) :- !,
+'$thread_set_default'(detached(Detached), _) :- !,
 	recorded('$thread_defaults', [Stack, Trail, System, _], Ref),
 	erase(Ref),
 	recorda('$thread_defaults', [Stack, Trail, System, Detached], _).
@@ -579,7 +580,7 @@ thread_sleep(Time) :-
 
 thread_signal(Id, Goal) :-
 	'$check_thread_or_alias'(Id, thread_signal(Id, Goal)),
-	'$check_callable'(Goal, thread_signal(Id, Goal)).
+	'$check_callable'(Goal, thread_signal(Id, Goal)),
 	'$thread_id_alias'(Id0, Id),
 	(	recorded('$thread_signal', [Id0| _], R), erase(R), fail
 	;	true
diff --git a/pl/utils.yap b/pl/utils.yap
index 89a5fe0ee..8cf90786c 100644
--- a/pl/utils.yap
+++ b/pl/utils.yap
@@ -184,10 +184,10 @@ call_with_args(A,A1,A2,A3,A4,A5,A6,A7,A8,A9,A10) :-
 	
 
 call_cleanup(Goal, Cleanup) :-
-	call_cleanup(Goal, Catcher, Cleanup).
+	call_cleanup(Goal, _Catcher, Cleanup).
 
 call_cleanup(Goal, Catcher, Cleanup) :-
-	catch('$call_cleanup'(Goal,Cleanup,Result),
+	catch('$call_cleanup'(Goal,Cleanup,_),
 	      Exception,
 	      '$cleanup_exception'(Exception,Catcher,Cleanup)).
 
@@ -806,5 +806,5 @@ nth_instance(X,Y,Z) :-
 	'$system_catch'('$query'(once(G), []),Module,Error,user:'$Error'(Error)).
 
 prolog_current_frame(Env) :-
-	X is $env.
+	Env is '$env'.
 
diff --git a/pl/yio.yap b/pl/yio.yap
index 65e0c7441..833c68d98 100644
--- a/pl/yio.yap
+++ b/pl/yio.yap
@@ -89,9 +89,9 @@ open(F,T,S,Opts) :-
 	N1 is I1\/N0,
 	N2 is I2/\N1,
 	'$process_open_opts'(L,N2,N, Aliases, Encoding).
-'$process_open_opts'([encoding(Enc)|L], N0, N, Aliases, T, EncCode) :-
-	'$valid_encoding'(Enc, EndCode),
-	'$process_open_opts'(L,N2,N, Aliases, _).
+'$process_open_opts'([encoding(Enc)|L], N0, N, Aliases, EncCode) :-
+	'$valid_encoding'(Enc, EncCode),
+	'$process_open_opts'(L, N0, N, Aliases, EncCode).
 '$process_open_opts'([eof_action(T)|L], N0, N, Aliases, Encoding) :-
 	'$value_open_opt'(T,eof_action,I1,I2),
 	N1 is I1\/N0,
@@ -232,8 +232,9 @@ open(F,T,S,Opts) :-
 
 '$check_open_encoding'(X, G) :- var(X), !,
 	'$do_error'(instantiation_error,G).
-'$check_open_encoding'(Encoding,_) :- '$valid_encoding'(Encoding,_), !.
-'$check_open_eof_action_arg'(Encoding,G) :-
+'$check_open_encoding'(Encoding,_) :-
+	'$valid_encoding'(Encoding,_), !.
+'$check_open_encoding'(Encoding,G) :-
 	'$do_error'(domain_error(io_mode,encoding(Encoding)),G).
 
 '$check_read_syntax_errors_arg'(X, G) :- var(X), !,