From e1f618739522102289e883476444ce5c9c31e356 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?V=C3=ADtor=20Santos=20Costa?= <vsc@dcc.fc.up.pt>
Date: Thu, 3 May 2012 00:16:11 +0100
Subject: [PATCH] make syntax error standard.

---
 C/errors.c      | 7 ++++++-
 C/iopreds.c     | 5 +++--
 pl/errors.yap   | 9 ---------
 pl/messages.yap | 8 ++++----
 4 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/C/errors.c b/C/errors.c
index 372462193..8c7d2fe6d 100644
--- a/C/errors.c
+++ b/C/errors.c
@@ -1431,9 +1431,11 @@ Yap_Error(yap_error_number type, Term where, char *format,...)
   case SYNTAX_ERROR:
     {
       int i;
+      Term ti[1];
 
       i = strlen(tmpbuf);
-      nt[0] = where;
+      ti[0] = MkAtomTerm(AtomSyntaxError);
+      nt[0] = Yap_MkApplTerm(FunctorShortSyntaxError, 1, ti);
       psize -= i;
       fun = FunctorError;
       serious = TRUE;
@@ -1807,6 +1809,9 @@ E);
 	LOCAL_Error_Size = 0L;
       }
       nt[1] = MkPairTerm(MkAtomTerm(Yap_LookupAtom(tmpbuf)), stack_dump);
+      if (type == SYNTAX_ERROR) {
+	nt[1] = MkPairTerm(where, nt[1]);
+      }
     }
   }
   if (serious) {
diff --git a/C/iopreds.c b/C/iopreds.c
index 6f6a3acf2..0f964d340 100644
--- a/C/iopreds.c
+++ b/C/iopreds.c
@@ -383,8 +383,9 @@ GenerateSyntaxError(Term *tp, TokEntry *tokstart, IOSTREAM *sno USES_REGS)
   if (tp) {
     Term et[2];
     Term t = MkVarTerm();
-    et[0] = syntax_error(tokstart, sno, &t);
-    et[1] = MkAtomTerm(Yap_LookupAtom("Syntax error"));
+    et[1] = MkPairTerm(syntax_error(tokstart, sno, &t), TermNil);
+    t = MkAtomTerm(AtomSyntaxError);
+    et[0] = Yap_MkApplTerm(FunctorShortSyntaxError,1,&t);
     *tp = Yap_MkApplTerm(FunctorError, 2, et);
   }
 }
diff --git a/pl/errors.yap b/pl/errors.yap
index ae064127f..fa55adaa5 100644
--- a/pl/errors.yap
+++ b/pl/errors.yap
@@ -255,8 +255,6 @@ print_message(Severity, Term) :-
 	   '$print_system_message'(Term, Severity, Lines)
 	), !.
 print_message(silent, _) :-  !.
-print_message(_, error(syntax_error(syntax_error(_,between(_,L,_),_,_,_,_,StreamName)),_)) :-  !,
-	format(user_error,'SYNTAX ERROR at ~a, close to ~d~n',[StreamName,L]).
 print_message(_, loading(A, F)) :- !,
 	format(user_error,'  % ~a ~a~n',[A,F]).
 print_message(_, loaded(A, F, _, Time, Space)) :- !,
@@ -284,13 +282,6 @@ print_message(_, Term) :-
 	current_prolog_flag(verbose, silent), !.
 '$print_system_message'(_, banner, _) :-
 	current_prolog_flag(verbose, silent), !.
-'$print_system_message'(Term, Level, Lines) :-
-	Term = error(syntax_error(syntax_error(_,_,_,_,_,_,_)),_), !,
-	flush_output(user_output),
-	flush_output(user_error),
-	'$messages':prefix(Level, LinePrefix, Stream, _, Lines), !,
-	% make sure we don't give a PC.
-	print_message_lines(Stream, LinePrefix, Lines).
 '$print_system_message'(Term, Level, Lines) :-
 	'$messages':prefix(Level, LinePrefix, Stream, Prefix),
 	'$messages':file_location(Prefix, LinesF, Lines), !,
diff --git a/pl/messages.yap b/pl/messages.yap
index 909548a82..2204299f1 100644
--- a/pl/messages.yap
+++ b/pl/messages.yap
@@ -283,14 +283,14 @@ system_message(error(resource_error(trail), Where)) -->
 	[ 'RESOURCE ERROR- not enough trail space' - [Where] ].
 system_message(error(signal(SIG,_), _)) -->
 	[ 'UNEXPECTED SIGNAL: ~a' - [SIG] ].
-system_message(error(syntax_error(G,_,Msg,[],_,0,File), _)) -->
+system_message(error(syntax_error(_), [syntax_error(G,_,Msg,[],_,0,File)|_])) -->
 	[ 'SYNTAX ERROR at "~a", goal ~q: ~a' - [File,G,Msg] ].
 % SWI like I/O error message.
-system_message(error(syntax_error(end_of_clause), stream(Stream, Line, _, _))) -->
+system_message(error(syntax_error(end_of_clause), [stream(Stream, Line, _, _)|_])) -->
 	[ 'SYNTAX ERROR ~a, stream ~w, near line ~d.' - ['Unexpected end of clause',Stream,Line] ].
-system_message(error(syntax_error(read(_),_,_,Term,Pos,Start,File), Where)) -->
+system_message(error(syntax_error(_), [syntax_error(read(_),_,_,Term,Pos,Start,File)|_])) -->
 	{ Term = [_|_] },
-	['~w' - [Where]],
+	['SYNTAX ERROR' - []],
 	syntax_error_line(File, Start, Pos),
 	syntax_error_term(10, Pos, Term),
 	[ '.' ].