Allow specification of semantic predicates.

[bison.git] / src / parse-gram.y

diff --git a/src/parse-gram.y b/src/parse-gram.y
index f45b323ca5e18c9a8ee380bde2505d2011289185..d588dfa8ab0f2ba015414a37cf7f8059e058d6cd 100644 (file)
--- a/src/parse-gram.y
+++ b/src/parse-gram.y
@@ -1,12 +1,13 @@
 %{/* Bison Grammar Parser                             -*- C -*-
 
 %{/* Bison Grammar Parser                             -*- C -*-
 

-   Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+   Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+   Free Software Foundation, Inc.

 
    This file is part of Bison, the GNU Compiler Compiler.
 
 
    This file is part of Bison, the GNU Compiler Compiler.
 

-   This program is free software; you can redistribute it and/or modify
+   This program is free software: you can redistribute it and/or modify

    it under the terms of the GNU General Public License as published by
    it under the terms of the GNU General Public License as published by

-   the Free Software Foundation; either version 2 of the License, or
+   the Free Software Foundation, either version 3 of the License, or

    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,


@@ -15,10 +16,7 @@
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License

-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-   02110-1301  USA
-*/
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

 
 #include <config.h>
 #include "system.h"
 
 #include <config.h>
 #include "system.h"


@@ -28,13 +26,13 @@
 #include "files.h"
 #include "getargs.h"
 #include "gram.h"
 #include "files.h"
 #include "getargs.h"
 #include "gram.h"

-#include "muscle_tab.h"
+#include "muscle-tab.h"
+#include "named-ref.h"

 #include "quotearg.h"
 #include "reader.h"
 #include "symlist.h"
 #include "scan-gram.h"
 #include "scan-code.h"
 #include "quotearg.h"
 #include "reader.h"
 #include "symlist.h"
 #include "scan-gram.h"
 #include "scan-code.h"

-#include "strverscmp.h"

 
 #define YYLLOC_DEFAULT(Current, Rhs, N)  (Current) = lloc_default (Rhs, N)
 static YYLTYPE lloc_default (YYLTYPE const *, int);
 
 #define YYLLOC_DEFAULT(Current, Rhs, N)  (Current) = lloc_default (Rhs, N)
 static YYLTYPE lloc_default (YYLTYPE const *, int);


@@ -52,54 +50,49 @@ static void version_check (location const *loc, char const *version);
 static void gram_error (location const *, char const *);
 
 static char const *char_name (char);
 static void gram_error (location const *, char const *);
 
 static char const *char_name (char);

-
-static void add_param (char const *, char *, location);
-
-static symbol_class current_class = unknown_sym;
-static uniqstr current_type = 0;
-static symbol *current_lhs;
-static location current_lhs_location;
-static int current_prec = 0;
-
-#ifdef UINT_FAST8_MAX
-# define YYTYPE_UINT8 uint_fast8_t
-#endif
-#ifdef INT_FAST8_MAX
-# define YYTYPE_INT8 int_fast8_t
-#endif
-#ifdef UINT_FAST16_MAX
-# define YYTYPE_UINT16 uint_fast16_t
-#endif
-#ifdef INT_FAST16_MAX
-# define YYTYPE_INT16 int_fast16_t
-#endif

 %}
 
 %}
 

+%code
+{
+  static int current_prec = 0;
+  static location current_lhs_location;
+  static named_ref *current_lhs_named_ref;
+  static symbol *current_lhs;
+  static symbol_class current_class = unknown_sym;
+  static uniqstr current_type = NULL;
+
+  #define YYTYPE_INT16 int_fast16_t
+  #define YYTYPE_INT8 int_fast8_t
+  #define YYTYPE_UINT16 uint_fast16_t
+  #define YYTYPE_UINT8 uint_fast8_t
+}
+

 %debug
 %verbose
 %defines
 %locations
 %pure-parser
 %debug
 %verbose
 %defines
 %locations
 %pure-parser

-%error-verbose
-%defines
+%define parse.error "verbose"

 %name-prefix="gram_"
 %name-prefix="gram_"

+%expect 0

 
 %initial-action
 {
   /* Bison's grammar can initial empty locations, hence a default
      location is needed. */
 
 %initial-action
 {
   /* Bison's grammar can initial empty locations, hence a default
      location is needed. */

-  boundary_set (&@$.start, current_file, 1, 0);
-  boundary_set (&@$.end, current_file, 1, 0);
+  boundary_set (&@$.start, current_file, 1, 1);
+  boundary_set (&@$.end, current_file, 1, 1);

 }
 
 }
 

-/* Only NUMBERS have a value.  */

 %union
 {
 %union
 {

+  assoc assoc;
+  char *code;
+  char const *chars;
+  int integer;
+  named_ref *named_ref;

   symbol *symbol;
   symbol_list *list;
   symbol *symbol;
   symbol_list *list;

-  int integer;
-  char *chars;
-  assoc assoc;

   uniqstr uniqstr;
   unsigned char character;
 };
   uniqstr uniqstr;
   unsigned char character;
 };


@@ -119,38 +112,36 @@ static int current_prec = 0;
 %token PERCENT_LEFT        "%left"
 %token PERCENT_RIGHT       "%right"
 %token PERCENT_NONASSOC    "%nonassoc"
 %token PERCENT_LEFT        "%left"
 %token PERCENT_RIGHT       "%right"
 %token PERCENT_NONASSOC    "%nonassoc"

+%token PERCENT_PRECEDENCE  "%precedence"

 
 %token PERCENT_PREC          "%prec"
 %token PERCENT_DPREC         "%dprec"
 %token PERCENT_MERGE         "%merge"
 
 
 %token PERCENT_PREC          "%prec"
 %token PERCENT_DPREC         "%dprec"
 %token PERCENT_MERGE         "%merge"
 

-

 /*----------------------.
 | Global Declarations.  |
 `----------------------*/
 
 %token
 /*----------------------.
 | Global Declarations.  |
 `----------------------*/
 
 %token

-  PERCENT_DEBUG           "%debug"
+  PERCENT_CODE            "%code"

   PERCENT_DEFAULT_PREC    "%default-prec"
   PERCENT_DEFINE          "%define"
   PERCENT_DEFINES         "%defines"
   PERCENT_ERROR_VERBOSE   "%error-verbose"
   PERCENT_EXPECT          "%expect"
   PERCENT_DEFAULT_PREC    "%default-prec"
   PERCENT_DEFINE          "%define"
   PERCENT_DEFINES         "%defines"
   PERCENT_ERROR_VERBOSE   "%error-verbose"
   PERCENT_EXPECT          "%expect"

-  PERCENT_EXPECT_RR      "%expect-rr"
+  PERCENT_EXPECT_RR       "%expect-rr"
+  PERCENT_FLAG            "%<flag>"

   PERCENT_FILE_PREFIX     "%file-prefix"
   PERCENT_GLR_PARSER      "%glr-parser"
   PERCENT_INITIAL_ACTION  "%initial-action"
   PERCENT_FILE_PREFIX     "%file-prefix"
   PERCENT_GLR_PARSER      "%glr-parser"
   PERCENT_INITIAL_ACTION  "%initial-action"

-  PERCENT_LEX_PARAM       "%lex-param"
-  PERCENT_LOCATIONS       "%locations"
+  PERCENT_LANGUAGE        "%language"

   PERCENT_NAME_PREFIX     "%name-prefix"
   PERCENT_NO_DEFAULT_PREC "%no-default-prec"
   PERCENT_NO_LINES        "%no-lines"
   PERCENT_NONDETERMINISTIC_PARSER
   PERCENT_NAME_PREFIX     "%name-prefix"
   PERCENT_NO_DEFAULT_PREC "%no-default-prec"
   PERCENT_NO_LINES        "%no-lines"
   PERCENT_NONDETERMINISTIC_PARSER

-                         "%nondeterministic-parser"
+                          "%nondeterministic-parser"

   PERCENT_OUTPUT          "%output"
   PERCENT_OUTPUT          "%output"

-  PERCENT_PARSE_PARAM     "%parse-param"
-  PERCENT_PURE_PARSER     "%pure-parser"
-  PERCENT_REQUIRE        "%require"
+  PERCENT_REQUIRE         "%require"

   PERCENT_SKELETON        "%skeleton"
   PERCENT_START           "%start"
   PERCENT_TOKEN_TABLE     "%token-table"
   PERCENT_SKELETON        "%skeleton"
   PERCENT_START           "%start"
   PERCENT_TOKEN_TABLE     "%token-table"


@@ -159,6 +150,8 @@ static int current_prec = 0;
 ;
 
 %token BRACED_CODE     "{...}"
 ;
 
 %token BRACED_CODE     "{...}"

+%token BRACED_PREDICATE "%?{...}"
+%token BRACKETED_ID    "[identifier]"

 %token CHAR            "char"
 %token EPILOGUE        "epilogue"
 %token EQUAL           "="
 %token CHAR            "char"
 %token EPILOGUE        "epilogue"
 %token EQUAL           "="


@@ -168,34 +161,94 @@ static int current_prec = 0;
 %token PIPE            "|"
 %token PROLOGUE        "%{...%}"
 %token SEMICOLON       ";"
 %token PIPE            "|"
 %token PROLOGUE        "%{...%}"
 %token SEMICOLON       ";"

-%token TYPE            "type"
+%token TAG             "<tag>"
+%token TAG_ANY         "<*>"
+%token TAG_NONE        "<>"

 
 %type <character> CHAR
 %printer { fputs (char_name ($$), stderr); } CHAR
 
 
 %type <character> CHAR
 %printer { fputs (char_name ($$), stderr); } CHAR
 

-%type <chars> STRING string_content "{...}" PROLOGUE EPILOGUE
+/* braceless is not to be used for rule or symbol actions, as it
+   calls code_props_plain_init.  */
+%type <chars> STRING "%{...%}" EPILOGUE braceless content.opt
+%type <code> "{...}" "%?{...}"

 %printer { fputs (quotearg_style (c_quoting_style, $$), stderr); }
 %printer { fputs (quotearg_style (c_quoting_style, $$), stderr); }

-         STRING string_content
-%printer { fprintf (stderr, "{\n%s\n}", $$); } "{...}" PROLOGUE EPILOGUE
+        STRING
+%printer { fprintf (stderr, "{\n%s\n}", $$); }
+        braceless content.opt "{...}" "%{...%}" EPILOGUE

 
 

-%type <uniqstr> TYPE ID ID_COLON
-%printer { fprintf (stderr, "<%s>", $$); } TYPE
-%printer { fputs ($$, stderr); } ID
+%type <uniqstr> BRACKETED_ID ID ID_COLON PERCENT_FLAG TAG variable
+%printer { fputs ($$, stderr); } <uniqstr>
+%printer { fprintf (stderr, "[%s]", $$); } BRACKETED_ID

 %printer { fprintf (stderr, "%s:", $$); } ID_COLON
 %printer { fprintf (stderr, "%s:", $$); } ID_COLON

+%printer { fprintf (stderr, "%%%s", $$); } PERCENT_FLAG
+%printer { fprintf (stderr, "<%s>", $$); } TAG

 
 %type <integer> INT
 
 %type <integer> INT

-%printer { fprintf (stderr, "%d", $$); } INT
+%printer { fprintf (stderr, "%d", $$); } <integer>

 
 

-%type <symbol> id id_colon symbol string_as_id
-%printer { fprintf (stderr, "%s", $$->tag); } id symbol string_as_id
+%type <symbol> id id_colon string_as_id symbol symbol.prec
+%printer { fprintf (stderr, "%s", $$->tag); } <symbol>

 %printer { fprintf (stderr, "%s:", $$->tag); } id_colon
 
 %type <assoc> precedence_declarator
 %printer { fprintf (stderr, "%s:", $$->tag); } id_colon
 
 %type <assoc> precedence_declarator

-%type <list>  symbols.1
+%type <list>  symbols.1 symbols.prec generic_symlist generic_symlist_item
+%type <named_ref> named_ref.opt
+
+/*---------.
+| %param.  |
+`---------*/
+%code requires
+{
+# ifndef PARAM_TYPE
+#  define PARAM_TYPE
+  typedef enum
+  {
+    param_none   = 0,
+    param_lex    = 1 << 0,
+    param_parse  = 1 << 1,
+    param_both   = param_lex | param_parse
+  } param_type;
+# endif
+};
+%code
+{
+  /** Add a lex-param and/or a parse-param.
+   *
+   * \param type  where to push this formal argument.
+   * \param decl  the formal argument.  Destroyed.
+   * \param loc   the location in the source.
+   */
+  static void add_param (param_type type, char *decl, location loc);
+  static param_type current_param = param_none;
+};
+%union
+{
+  param_type param;
+}
+%token <param> PERCENT_PARAM "%param";
+%printer
+{
+  switch ($$)
+    {
+#define CASE(In, Out)                                           \
+      case param_ ## In: fputs ("%" #Out, stderr); break
+      CASE(lex,   lex-param);
+      CASE(parse, parse-param);
+      CASE(both,  param);
+#undef CASE
+      case param_none: aver (false); break;
+    }
+} <param>;
+
+
+                     /*==========\
+                     | Grammar.  |
+                     \==========*/

 %%
 
 input:
 %%
 
 input:

-  declarations "%%" grammar epilogue.opt
+  prologue_declarations "%%" grammar epilogue.opt

 ;
 
 
 ;
 
 


@@ -203,27 +256,47 @@ input:
        | Declarations: before the first %%.  |
        `------------------------------------*/
 
        | Declarations: before the first %%.  |
        `------------------------------------*/
 

-declarations:
+prologue_declarations:

   /* Nothing */
   /* Nothing */

-| declarations declaration
+| prologue_declarations prologue_declaration

 ;
 
 ;
 

-declaration:
+prologue_declaration:

   grammar_declaration
   grammar_declaration

-| PROLOGUE                         { prologue_augment (translate_code ($1, @1),
-                                                      @1); }
-| "%debug"                                 { debug_flag = true; }
-| "%define" string_content
-    {
-      static char one[] = "1";
-      muscle_insert ($2, one);
-    }
-| "%define" string_content string_content  { muscle_insert ($2, $3); }
-| "%defines"                               { defines_flag = true; }
-| "%error-verbose"                         { error_verbose = true; }
-| "%expect" INT                            { expected_sr_conflicts = $2; }
-| "%expect-rr" INT                        { expected_rr_conflicts = $2; }
-| "%file-prefix" "=" string_content        { spec_file_prefix = $3; }
+| "%{...%}"
+    {
+      code_props plain_code;
+      code_props_plain_init (&plain_code, $1, @1);
+      code_props_translate_code (&plain_code);
+      gram_scanner_last_string_free ();
+      muscle_code_grow (union_seen ? "post_prologue" : "pre_prologue",
+                        plain_code.code, @1);
+      code_scanner_last_string_free ();
+    }
+| "%<flag>"
+    {
+      muscle_percent_define_ensure ($1, @1, true);
+    }
+| "%define" variable content.opt
+    {
+      muscle_percent_define_insert ($2, @2, $3,
+                                    MUSCLE_PERCENT_DEFINE_GRAMMAR_FILE);
+    }
+| "%defines"                       { defines_flag = true; }
+| "%defines" STRING
+    {
+      defines_flag = true;
+      spec_defines_file = xstrdup ($2);
+    }
+| "%error-verbose"
+    {
+      muscle_percent_define_insert ("parse.error", @1, "verbose",
+                                    MUSCLE_PERCENT_DEFINE_GRAMMAR_FILE);
+    }
+| "%expect" INT                    { expected_sr_conflicts = $2; }
+| "%expect-rr" INT                { expected_rr_conflicts = $2; }
+| "%file-prefix" STRING            { spec_file_prefix = $2; }
+| "%file-prefix" "=" STRING        { spec_file_prefix = $3; } /* deprecated */

 | "%glr-parser"
     {
       nondeterministic_parser = true;
 | "%glr-parser"
     {
       nondeterministic_parser = true;


@@ -231,24 +304,62 @@ declaration:
     }
 | "%initial-action" "{...}"
     {
     }
 | "%initial-action" "{...}"
     {

-      muscle_code_grow ("initial_action", translate_symbol_action ($2, @2), @2);
-    }
-| "%lex-param" "{...}"                    { add_param ("lex_param", $2, @2); }
-| "%locations"                             { locations_flag = true; }
-| "%name-prefix" "=" string_content        { spec_name_prefix = $3; }
-| "%no-lines"                              { no_lines_flag = true; }
-| "%nondeterministic-parser"              { nondeterministic_parser = true; }
-| "%output" "=" string_content             { spec_outfile = $3; }
-| "%parse-param" "{...}"                  { add_param ("parse_param", $2, @2); }
-| "%pure-parser"                           { pure_parser = true; }
-| "%require" string_content                { version_check (&@2, $2); }
-| "%skeleton" string_content               { skeleton = $2; }
-| "%token-table"                           { token_table_flag = true; }
-| "%verbose"                               { report_flag = report_states; }
-| "%yacc"                                  { yacc_flag = true; }
+      code_props action;
+      code_props_symbol_action_init (&action, $2, @2);
+      code_props_translate_code (&action);
+      gram_scanner_last_string_free ();
+      muscle_code_grow ("initial_action", action.code, @2);
+      code_scanner_last_string_free ();
+    }
+| "%language" STRING           { language_argmatch ($2, grammar_prio, @1); }
+| "%name-prefix" STRING         { spec_name_prefix = $2; }
+| "%name-prefix" "=" STRING     { spec_name_prefix = $3; } /* deprecated */
+| "%no-lines"                   { no_lines_flag = true; }
+| "%nondeterministic-parser"   { nondeterministic_parser = true; }
+| "%output" STRING              { spec_outfile = $2; }
+| "%output" "=" STRING          { spec_outfile = $3; }  /* deprecated */
+| "%param" { current_param = $1; } params { current_param = param_none; }
+| "%require" STRING             { version_check (&@2, $2); }
+| "%skeleton" STRING
+    {
+      char const *skeleton_user = $2;
+      if (strchr (skeleton_user, '/'))
+        {
+          size_t dir_length = strlen (current_file);
+          char *skeleton_build;
+          while (dir_length && current_file[dir_length - 1] != '/')
+            --dir_length;
+          while (dir_length && current_file[dir_length - 1] == '/')
+            --dir_length;
+          skeleton_build =
+            xmalloc (dir_length + 1 + strlen (skeleton_user) + 1);
+          if (dir_length > 0)
+            {
+              strncpy (skeleton_build, current_file, dir_length);
+              skeleton_build[dir_length++] = '/';
+            }
+          strcpy (skeleton_build + dir_length, skeleton_user);
+          skeleton_user = uniqstr_new (skeleton_build);
+          free (skeleton_build);
+        }
+      skeleton_arg (skeleton_user, grammar_prio, @1);
+    }
+| "%token-table"                { token_table_flag = true; }
+| "%verbose"                    { report_flag |= report_states; }
+| "%yacc"                       { yacc_flag = true; }

 | /*FIXME: Err?  What is this horror doing here? */ ";"
 ;
 
 | /*FIXME: Err?  What is this horror doing here? */ ";"
 ;
 

+params:
+   params "{...}"  { add_param (current_param, $2, @2); }
+| "{...}"          { add_param (current_param, $1, @1); }
+;
+
+
+/*----------------------.
+| grammar_declaration.  |
+`----------------------*/
+

 grammar_declaration:
   precedence_declaration
 | symbol_declaration
 grammar_declaration:
   precedence_declaration
 | symbol_declaration


@@ -256,20 +367,18 @@ grammar_declaration:
     {
       grammar_start_symbol_set ($2, @2);
     }
     {
       grammar_start_symbol_set ($2, @2);
     }

-| "%destructor" "{...}" symbols.1
+| "%destructor" "{...}" generic_symlist

     {
       symbol_list *list;
     {
       symbol_list *list;

-      const char *action = translate_symbol_action ($2, @2);

       for (list = $3; list; list = list->next)
       for (list = $3; list; list = list->next)

-       symbol_destructor_set (list->sym, action, @2);
+       symbol_list_destructor_set (list, $2, @2);

       symbol_list_free ($3);
     }
       symbol_list_free ($3);
     }

-| "%printer" "{...}" symbols.1
+| "%printer" "{...}" generic_symlist

     {
       symbol_list *list;
     {
       symbol_list *list;

-      const char *action = translate_symbol_action ($2, @2);

       for (list = $3; list; list = list->next)
       for (list = $3; list; list = list->next)

-       symbol_printer_set (list->sym, action, @2);
+       symbol_list_printer_set (list, $2, @2);

       symbol_list_free ($3);
     }
 | "%default-prec"
       symbol_list_free ($3);
     }
 | "%default-prec"


@@ -280,12 +389,24 @@ grammar_declaration:
     {
       default_prec = false;
     }
     {
       default_prec = false;
     }

+| "%code" braceless
+    {
+      /* Do not invoke muscle_percent_code_grow here since it invokes
+         muscle_user_name_list_grow.  */
+      muscle_code_grow ("percent_code()", $2, @2);
+      code_scanner_last_string_free ();
+    }
+| "%code" ID braceless
+    {
+      muscle_percent_code_grow ($2, @2, $3, @3);
+      code_scanner_last_string_free ();
+    }

 ;
 
 
 ;
 
 

-/*----------*
- | %union.  |
- *----------*/
+/*---------.
+| %union.  |
+`---------*/

 
 %token PERCENT_UNION "%union";
 
 
 %token PERCENT_UNION "%union";
 


@@ -295,21 +416,11 @@ union_name:
 ;
 
 grammar_declaration:
 ;
 
 grammar_declaration:

-  "%union" union_name "{...}"
+  "%union" union_name braceless

     {
     {

-      char const *body = $3;
-
-      if (typed)
-       {
-         /* Concatenate the union bodies, turning the first one's
-            trailing '}' into '\n', and omitting the second one's '{'.  */
-         char *code = muscle_find ("stype");
-         code[strlen (code) - 1] = '\n';
-         body++;
-       }
-
-      typed = true;
-      muscle_code_grow ("stype", body, @3);
+      union_seen = true;
+      muscle_code_grow ("stype", $3, @3);
+      code_scanner_last_string_free ();

     }
 ;
 
     }
 ;
 


@@ -327,24 +438,25 @@ symbol_declaration:
       current_class = unknown_sym;
       current_type = NULL;
     }
       current_class = unknown_sym;
       current_type = NULL;
     }

-| "%type" TYPE symbols.1
+| "%type" TAG symbols.1

     {
       symbol_list *list;
     {
       symbol_list *list;

+      tag_seen = true;

       for (list = $3; list; list = list->next)
       for (list = $3; list; list = list->next)

-       symbol_type_set (list->sym, $2, @2);
+       symbol_type_set (list->content.sym, $2, @2);

       symbol_list_free ($3);
     }
 ;
 
 precedence_declaration:
       symbol_list_free ($3);
     }
 ;
 
 precedence_declaration:

-  precedence_declarator type.opt symbols.1
+  precedence_declarator tag.opt symbols.prec

     {
       symbol_list *list;
       ++current_prec;
       for (list = $3; list; list = list->next)
        {
     {
       symbol_list *list;
       ++current_prec;
       for (list = $3; list; list = list->next)
        {

-         symbol_type_set (list->sym, current_type, @2);
-         symbol_precedence_set (list->sym, current_prec, $1, @1);
+         symbol_type_set (list->content.sym, current_type, @2);
+         symbol_precedence_set (list->content.sym, current_prec, $1, @1);

        }
       symbol_list_free ($3);
       current_type = NULL;
        }
       symbol_list_free ($3);
       current_type = NULL;


@@ -352,27 +464,56 @@ precedence_declaration:
 ;
 
 precedence_declarator:
 ;
 
 precedence_declarator:

-  "%left"     { $$ = left_assoc; }
-| "%right"    { $$ = right_assoc; }
-| "%nonassoc" { $$ = non_assoc; }
+  "%left"       { $$ = left_assoc; }
+| "%right"      { $$ = right_assoc; }
+| "%nonassoc"   { $$ = non_assoc; }
+| "%precedence" { $$ = precedence_assoc; }

 ;
 
 ;
 

-type.opt:
+tag.opt:

   /* Nothing. */ { current_type = NULL; }
   /* Nothing. */ { current_type = NULL; }

-| TYPE           { current_type = $1; }
+| TAG            { current_type = $1; tag_seen = true; }
+;
+
+/* Just like symbols.1 but accept INT for the sake of POSIX.  */
+symbols.prec:
+  symbol.prec
+    { $$ = symbol_list_sym_new ($1, @1); }
+| symbols.prec symbol.prec
+    { $$ = symbol_list_prepend ($1, symbol_list_sym_new ($2, @2)); }

 ;
 
 ;
 

-/* One or more nonterminals to be %typed. */
+symbol.prec:
+    symbol { $$ = $1; }
+  | symbol INT { $$ = $1; symbol_user_token_number_set ($1, $2, @2); }
+  ;
+
+/* One or more symbols to be %typed. */

 symbols.1:
 symbols.1:

-  symbol            { $$ = symbol_list_new ($1, @1); }
-| symbols.1 symbol  { $$ = symbol_list_prepend ($1, $2, @2); }
+  symbol
+    { $$ = symbol_list_sym_new ($1, @1); }
+| symbols.1 symbol
+    { $$ = symbol_list_prepend ($1, symbol_list_sym_new ($2, @2)); }
+;
+
+generic_symlist:
+  generic_symlist_item { $$ = $1; }
+| generic_symlist generic_symlist_item { $$ = symbol_list_prepend ($1, $2); }
+;
+
+generic_symlist_item:
+  symbol    { $$ = symbol_list_sym_new ($1, @1); }
+| TAG       { $$ = symbol_list_type_new ($1, @1); }
+| "<*>"     { $$ = symbol_list_default_tagged_new (@1); }
+| "<>"      { $$ = symbol_list_default_tagless_new (@1); }

 ;
 
 /* One token definition.  */
 symbol_def:
 ;
 
 /* One token definition.  */
 symbol_def:

-  TYPE
+  TAG

      {
        current_type = $1;
      {
        current_type = $1;

+       tag_seen = true;

      }
 | id
      {
      }
 | id
      {


@@ -428,7 +569,8 @@ rules_or_grammar_declaration:
 ;
 
 rules:
 ;
 
 rules:

-  id_colon { current_lhs = $1; current_lhs_location = @1; } rhses.1
+  id_colon named_ref.opt { current_lhs = $1; current_lhs_location = @1;
+    current_lhs_named_ref = $2; } rhses.1

 ;
 
 rhses.1:
 ;
 
 rhses.1:


@@ -439,31 +581,74 @@ rhses.1:
 
 rhs:
   /* Nothing.  */
 
 rhs:
   /* Nothing.  */

-    { grammar_current_rule_begin (current_lhs, current_lhs_location); }
-| rhs symbol
-    { grammar_current_rule_symbol_append ($2, @2); }
-| rhs "{...}"
-    { grammar_current_rule_action_append (gram_last_string,
-                                         gram_last_braced_code_loc); }
+    { grammar_current_rule_begin (current_lhs, current_lhs_location,
+                                 current_lhs_named_ref); }
+| rhs symbol named_ref.opt
+    { grammar_current_rule_symbol_append ($2, @2, $3); }
+| rhs "{...}" named_ref.opt
+    { grammar_current_rule_action_append ($2, @2, $3, false); }
+| rhs "%?{...}" 
+    { grammar_current_rule_action_append ($2, @2, NULL, true); }

 | rhs "%prec" symbol
     { grammar_current_rule_prec_set ($3, @3); }
 | rhs "%dprec" INT
     { grammar_current_rule_dprec_set ($3, @3); }
 | rhs "%prec" symbol
     { grammar_current_rule_prec_set ($3, @3); }
 | rhs "%dprec" INT
     { grammar_current_rule_dprec_set ($3, @3); }

-| rhs "%merge" TYPE
+| rhs "%merge" TAG

     { grammar_current_rule_merge_set ($3, @3); }
 ;
 
     { grammar_current_rule_merge_set ($3, @3); }
 ;
 

+named_ref.opt:
+  /* Nothing. */ { $$ = 0; }
+|
+  BRACKETED_ID   { $$ = named_ref_new($1, @1); }
+;
+
+/*---------------------------.
+| variable and content.opt.  |
+`---------------------------*/

 
 

-/*---------------*
- | Identifiers.  |
- *---------------*/
+/* The STRING form of variable is deprecated and is not M4-friendly.
+   For example, M4 fails for `%define "[" "value"'.  */
+variable:
+  ID
+| STRING { $$ = uniqstr_new ($1); }
+;
+
+/* Some content or empty by default. */
+content.opt:
+  /* Nothing. */   { $$ = ""; }
+| ID { $$ = $1; }
+| STRING
+;
+
+
+/*------------.
+| braceless.  |
+`------------*/
+
+braceless:
+  "{...}"
+    {
+      code_props plain_code;
+      $1[strlen ($1) - 1] = '\n';
+      code_props_plain_init (&plain_code, $1+1, @1);
+      code_props_translate_code (&plain_code);
+      gram_scanner_last_string_free ();
+      $$ = plain_code.code;
+    }
+;
+
+
+/*--------------.
+| Identifiers.  |
+`--------------*/

 
 /* Identifiers are returned as uniqstr values by the scanner.
    Depending on their use, we may need to make them genuine symbols.  */
 
 id:
   ID
 
 /* Identifiers are returned as uniqstr values by the scanner.
    Depending on their use, we may need to make them genuine symbols.  */
 
 id:
   ID

-    { $$ = symbol_get ($1, @1); }
+    { $$ = symbol_from_uniqstr ($1, @1); }

 | CHAR
     {
       $$ = symbol_get (char_name ($1), @1);
 | CHAR
     {
       $$ = symbol_get (char_name ($1), @1);


@@ -473,7 +658,7 @@ id:
 ;
 
 id_colon:
 ;
 
 id_colon:

-  ID_COLON { $$ = symbol_get ($1, @1); }
+  ID_COLON { $$ = symbol_from_uniqstr ($1, @1); }

 ;
 
 
 ;
 
 


@@ -491,19 +676,16 @@ string_as_id:
     }
 ;
 
     }
 ;
 

-/* A string used for its contents.  Don't quote it.  */
-string_content:
-  STRING
-    { $$ = $1; }
-;
-
-

 epilogue.opt:
   /* Nothing.  */
 | "%%" EPILOGUE
     {
 epilogue.opt:
   /* Nothing.  */
 | "%%" EPILOGUE
     {

-      muscle_code_grow ("epilogue", translate_code ($2, @2), @2);
+      code_props plain_code;
+      code_props_plain_init (&plain_code, $2, @2);
+      code_props_translate_code (&plain_code);

       gram_scanner_last_string_free ();
       gram_scanner_last_string_free ();

+      muscle_code_grow ("epilogue", plain_code.code, @2);
+      code_scanner_last_string_free ();

     }
 ;
 
     }
 ;
 


@@ -540,34 +722,33 @@ lloc_default (YYLTYPE const *rhs, int n)
 }
 
 
 }
 
 

-/* Add a lex-param or a parse-param (depending on TYPE) with
-   declaration DECL and location LOC.  */
-

 static void
 static void

-add_param (char const *type, char *decl, location loc)
+add_param (param_type type, char *decl, location loc)

 {
   static char const alphanum[26 + 26 + 1 + 10] =
     "abcdefghijklmnopqrstuvwxyz"
     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
     "_"
     "0123456789";
 {
   static char const alphanum[26 + 26 + 1 + 10] =
     "abcdefghijklmnopqrstuvwxyz"
     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
     "_"
     "0123456789";

+

   char const *name_start = NULL;
   char const *name_start = NULL;

-  char *p;
-
-  /* Stop on last actual character.  */
-  for (p = decl; p[1]; p++)
-    if ((p == decl
-        || ! memchr (alphanum, p[-1], sizeof alphanum))
-       && memchr (alphanum, p[0], sizeof alphanum - 10))
-      name_start = p;
-
-  /* Strip the surrounding '{' and '}', and any blanks just inside
-     the braces.  */
-  while (*--p == ' ' || *p == '\t')
-    continue;
-  p[1] = '\0';
-  while (*++decl == ' ' || *decl == '\t')
-    continue;
+  {
+    char *p;
+    /* Stop on last actual character.  */
+    for (p = decl; p[1]; p++)
+      if ((p == decl
+           || ! memchr (alphanum, p[-1], sizeof alphanum))
+          && memchr (alphanum, p[0], sizeof alphanum - 10))
+        name_start = p;
+
+    /* Strip the surrounding '{' and '}', and any blanks just inside
+       the braces.  */
+    while (*--p == ' ' || *p == '\t')
+      continue;
+    p[1] = '\0';
+    while (*++decl == ' ' || *decl == '\t')
+      continue;
+  }

 
   if (! name_start)
     complain_at (loc, _("missing identifier in parameter declaration"));
 
   if (! name_start)
     complain_at (loc, _("missing identifier in parameter declaration"));


@@ -584,13 +765,17 @@ add_param (char const *type, char *decl, location loc)
       name = xmalloc (name_len + 1);
       memcpy (name, name_start, name_len);
       name[name_len] = '\0';
       name = xmalloc (name_len + 1);
       memcpy (name, name_start, name_len);
       name[name_len] = '\0';

-      muscle_pair_list_grow (type, decl, name);
+      if (type & param_lex)
+        muscle_pair_list_grow ("lex_param", decl, name);
+      if (type & param_parse)
+        muscle_pair_list_grow ("parse_param", decl, name);

       free (name);
     }
 
   gram_scanner_last_string_free ();
 }
 
       free (name);
     }
 
   gram_scanner_last_string_free ();
 }
 

+

 static void
 version_check (location const *loc, char const *version)
 {
 static void
 version_check (location const *loc, char const *version)
 {