@$ in destructor

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>

        Prepare @$ in %destructor, but currently don't bind it in the
        skeleton, as %location use is not cleaned up yet.

        * src/scan-gram.l (handle_dollar, handle_destructor_at)
        (handle_action_at): New.
        (handle_at, handle_action_dollar, handle_destructor_dollar): Take
        a braced_code_t and a location as additional arguments.
        (handle_destructor_dollar): Instead of requiring `b4_eval', just
        unquote one when outputting `b4_dollar_dollar'.
        Adjust callers.
        * data/bison.simple (b4_eval): Remove.
        (b4_symbol_destructor): Adjust.
        * tests/input.at (Invalid @n): Adjust.

Index: data/bison.simple
===================================================================
RCS file: /cvsroot/bison/bison/data/bison.simple,v
retrieving revision 1.37
diff -u -u -r1.37 bison.simple
--- data/bison.simple 18 Jun 2002 11:37:20 -0000 1.37
+++ data/bison.simple 19 Jun 2002 08:21:48 -0000
@@ -1275,21 +1275,13 @@
 `-------------------------------------------------*/
 
 m4_divert_push([KILL])# M4 code.
-# b4_eval
-# -------
-# FIXME: This is really wrong, we no longer guarantee we don't evaluate
-# the user's input.  This demonstrates that decoding actions (BRACED_CODE)
-# ought to be done when output, not when read.
-m4_define([b4_eval],
-[$*])
-
 # b4_symbol_destructor(SYMBOL-NUMBER, DESTRUCTOR, TYPE-NAME)
 # ----------------------------------------------------------
 m4_define([b4_symbol_destructor],
 [m4_pushdef([b4_dollar_dollar], [symbol_value.$6])dnl
       case $4: /* $3 */
 #line $2 "$1"
-        b4_eval($5);
+        $5;
 #line __oline__ "__ofile__"
         break;
 m4_popdef([b4_dollar_dollar])])
Index: src/scan-gram.l
===================================================================
RCS file: /cvsroot/bison/bison/src/scan-gram.l,v
retrieving revision 1.11
diff -u -u -r1.11 scan-gram.l
--- src/scan-gram.l 17 Jun 2002 08:43:11 -0000 1.11
+++ src/scan-gram.l 19 Jun 2002 08:21:48 -0000
@@ -76,13 +76,13 @@
 }
 
 
-
 static int braces_level = 0;
 static int percent_percent_count = 0;
 
-static void handle_action_dollar PARAMS ((char *cp, location_t location));
-static void handle_destructor_dollar PARAMS ((char *cp, location_t location));
-static void handle_at PARAMS ((char *cp));
+static void handle_dollar PARAMS ((braced_code_t code_kind,
+                                  char *cp, location_t location));
+static void handle_at PARAMS ((braced_code_t code_kind,
+                              char *cp, location_t location));
 
 %}
 %x SC_COMMENT
@@ -443,19 +443,10 @@
 
   "{"                  YY_OBS_GROW; braces_level++;
 
-  "$"("<"[^>]+">")?(-?[0-9]+|"$") {
-    switch (current_braced_code)
-      {
-      case action_braced_code:
-       handle_action_dollar (yytext, *yylloc);
-       break;
-
-      case destructor_braced_code:
-       handle_destructor_dollar (yytext, *yylloc);
-       break;
-      }
-  }
-  "@"(-?[0-9]+|"$")               { handle_at (yytext); }
+  "$"("<"[^>]+">")?(-?[0-9]+|"$") { handle_dollar (current_braced_code,
+                                                  yytext, *yylloc); }
+  "@"(-?[0-9]+|"$")               { handle_at (current_braced_code,
+                                              yytext, *yylloc); }
 
   address@hidden/\'\"\{\}\n\r]+ YY_OBS_GROW;
   {eols}       YY_OBS_GROW; YY_LINES;
@@ -532,7 +523,7 @@
 | Output to the STRING_OBSTACK a reference to this semantic value.  |
 `------------------------------------------------------------------*/
 
-static void
+static inline void
 handle_action_dollar (char *cp, location_t location)
 {
   const char *type_name = NULL;
@@ -596,21 +587,17 @@
 }
 
 
-/*---------------------------------------------------------------.
-| CP is pointing to $$ in a destructor.  This should probably be |
-| done once the grammar completely parsed, instead of during its |
-| parsing, since that means %type must be specified before       |
-| %destructor.                                                   |
-`---------------------------------------------------------------*/
+/*---------------------------------------.
+| CP is pointing to $$ in a destructor.  |
+`---------------------------------------*/
 
-static void
+static inline void
 handle_destructor_dollar (char *cp, location_t location)
 {
   ++cp;
   if (*cp == '$')
     {
-      /* FIXME: We should find something more robust.  */
-      obstack_sgrow (&string_obstack, "b4_dollar_dollar");
+      obstack_sgrow (&string_obstack, "]b4_dollar_dollar[");
     }
   else
     {
@@ -620,32 +607,55 @@
     }
 }
 
-/*-------------------------------------------------------.
-| CP is pointing to a location (i.e., a `@').  Output to |
-| STRING_OBSTACK a reference to this location.           |
-`-------------------------------------------------------*/
+
+/*-----------------------------------------------------------------.
+| Dispatch onto handle_action_dollar, or handle_destructor_dollar, |
+| depending upon CODE_KIND.                                        |
+`-----------------------------------------------------------------*/
 
 static void
-handle_at (char *cp)
+handle_dollar (braced_code_t braced_code_kind,
+              char *text, location_t location)
+{
+  switch (braced_code_kind)
+    {
+    case action_braced_code:
+      handle_action_dollar (text, location);
+      break;
+
+    case destructor_braced_code:
+      handle_destructor_dollar (text, location);
+      break;
+    }
+}
+
+
+/*------------------------------------------------------.
+| TEXT is a location token (i.e., a address@hidden').  Output to |
+| STRING_OBSTACK a reference to this location.          |
+`------------------------------------------------------*/
+
+static inline void
+handle_action_at (char *text, location_t location)
 {
   locations_flag = 1;
-  ++cp;
+  ++text;
 
-  if (*cp == '$')
+  if (*text == '$')
     {
       obstack_sgrow (&string_obstack, "]b4_lhs_location[");
     }
-  else if (isdigit (*cp) || *cp == '-')
+  else if (isdigit (*text) || *text == '-')
     {
       /* RULE_LENGTH is the number of values in the current rule so
         far, which says where to find `$0' with respect to the top of
         the stack.  It is not the same as the rule->length in the
         case of mid rule actions.  */
       int rule_length = symbol_list_length (current_rule->next);
-      int n = strtol (cp, &cp, 10);
+      int n = strtol (text, &text, 10);
 
       if (n > rule_length)
-       complain (_("invalid value: %s%d"), "@", n);
+       complain_at (location, _("invalid value: %s%d"), "@", n);
       else
        obstack_fgrow2 (&string_obstack, "]b4_rhs_location([%d], [%d])[",
                        rule_length, n);
@@ -653,17 +663,69 @@
   else
     {
       char buf[] = "@c";
-      buf[1] = *cp;
-      complain (_("%s is invalid"), quote (buf));
+      buf[1] = *text;
+      complain_at (location, _("%s is invalid"), quote (buf));
     }
 }
 
+
+/*--------------------------------------------.
+| TEXT is expexted tp be @$ in a destructor.  |
+`--------------------------------------------*/
+
+static inline void
+handle_destructor_at (char *text, location_t location)
+{
+  ++text;
+  if (*text == '$')
+    {
+      obstack_sgrow (&string_obstack, "]b4_at_dollar[");
+    }
+  else
+    {
+      char buf[] = "$c";
+      buf[1] = *text;
+      complain_at (location, _("%s is invalid"), quote (buf));
+    }
+}
+
+
+/*-------------------------------------------------------------------.
+| Dispatch onto handle_action_at, or handle_destructor_at, depending |
+| upon CODE_KIND.                                                    |
+`-------------------------------------------------------------------*/
+
+static void
+handle_at (braced_code_t braced_code_kind,
+          char *text, location_t location)
+{
+  switch (braced_code_kind)
+    {
+    case action_braced_code:
+      handle_action_at (text, location);
+      break;
+
+    case destructor_braced_code:
+      handle_destructor_at (text, location);
+      break;
+    }
+}
+
+
+/*-------------------------.
+| Initialize the scanner.  |
+`-------------------------*/
+
 void
 scanner_initialize (void)
 {
   obstack_init (&string_obstack);
 }
 
+
+/*-----------------------------------------------.
+| Free all the memory allocated to the scanner.  |
+`-----------------------------------------------*/
 
 void
 scanner_free (void)
Index: tests/input.at
===================================================================
RCS file: /cvsroot/bison/bison/tests/input.at,v
retrieving revision 1.7
diff -u -u -r1.7 input.at
--- tests/input.at 17 Jun 2002 07:04:49 -0000 1.7
+++ tests/input.at 19 Jun 2002 08:21:48 -0000
@@ -75,7 +75,7 @@
 ]])
 
 AT_CHECK([bison input.y], [1], [],
-[[input.y:2: invalid value: @1
+[[input.y:2.6-14: invalid value: @1
 ]])
 
 AT_CLEANUP