(scan_lists): Signal errors using scan-error.

(syms_of_syntax): Set up Qscan_error.

diff --git a/src/syntax.c b/src/syntax.c
index 2233993..1404bfa 100644 (file)
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -26,7 +26,7 @@ Boston, MA 02111-1307, USA.  */
 #include "buffer.h"
 #include "syntax.h"
 
-Lisp_Object Qsyntax_table_p, Qsyntax_table;
+Lisp_Object Qsyntax_table_p, Qsyntax_table, Qscan_error;
 
 static void scan_sexps_forward ();
 static int char_quoted ();
@@ -943,6 +943,7 @@ scan_lists (from, count, depth, sexpflag)
   register enum syntaxcode code;
   int min_depth = depth;    /* Err out if depth gets less than this. */
   int comstyle = 0;        /* style of comment encountered */
+  int last_good = from;
 
   if (depth > 0) min_depth = 0;
 
@@ -956,6 +957,8 @@ scan_lists (from, count, depth, sexpflag)
        {
          c = FETCH_CHAR (from);
          code = SYNTAX (c);
+         if (depth == min_depth)
+           last_good = from;
          from++;
          if (from < stop && SYNTAX_COMSTART_FIRST (c)
              && SYNTAX_COMSTART_SECOND (FETCH_CHAR (from))
@@ -1053,7 +1056,10 @@ scan_lists (from, count, depth, sexpflag)
            close1:
              if (!--depth) goto done;
              if (depth < min_depth)
-               error ("Containing expression ends prematurely");
+               Fsignal (Qscan_error,
+                        Fcons (build_string ("Containing expression ends prematurely"),
+                               Fcons (make_number (last_good),
+                                      Fcons (make_number (from), Qnil))));
              break;
 
            case Sstring:
@@ -1097,6 +1103,8 @@ scan_lists (from, count, depth, sexpflag)
            from--;
          c = FETCH_CHAR (from);
          code = SYNTAX (c);
+         if (depth == min_depth)
+           last_good = from;
          comstyle = 0;
          if (code == Sendcomment)
            comstyle = SYNTAX_COMMENT_STYLE (c);
@@ -1155,7 +1163,10 @@ scan_lists (from, count, depth, sexpflag)
            open2:
              if (!--depth) goto done2;
              if (depth < min_depth)
-               error ("Containing expression ends prematurely");
+               Fsignal (Qscan_error,
+                        Fcons (build_string ("Containing expression ends prematurely"),
+                               Fcons (make_number (last_good),
+                                      Fcons (make_number (from), Qnil))));
              break;
 
            case Sendcomment:
@@ -1331,7 +1342,11 @@ scan_lists (from, count, depth, sexpflag)
   return val;
 
  lose:
-  error ("Unbalanced parentheses");
+  Fsignal (Qscan_error,
+          Fcons (build_string ("Unbalanced parentheses"),
+                 Fcons (make_number (last_good),
+                        Fcons (make_number (from), Qnil))));
+
   /* NOTREACHED */
 }
 
@@ -1796,6 +1811,13 @@ syms_of_syntax ()
   Qsyntax_table_p = intern ("syntax-table-p");
   staticpro (&Qsyntax_table_p);
 
+  Qscan_error = intern ("scan-error");
+  staticpro (&Qscan_error);
+  Fput (Qscan_error, Qerror_conditions,
+       Fcons (Qerror, Qnil));
+  Fput (Qscan_error, Qerror_message,
+       build_string ("Scan error"));
+
   DEFVAR_BOOL ("parse-sexp-ignore-comments", &parse_sexp_ignore_comments,
     "Non-nil means `forward-sexp', etc., should treat comments as whitespace.");