(rules_or_grammar_declaration): Require a

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

diff --git a/src/parse-gram.y b/src/parse-gram.y
index 241dcdceaf70cd5087a57052793392b224ee7098..02608bb0476352b7139973e54616c30b08dbb73b 100644 (file)
--- a/src/parse-gram.y
+++ b/src/parse-gram.y
@@ -1,5 +1,6 @@
 /* Bison Grammar Parser                             -*- C -*-
 /* Bison Grammar Parser                             -*- C -*-

-   Copyright (C) 2002 Free Software Foundation, Inc.
+
+   Copyright (C) 2002, 2003 Free Software Foundation, Inc.

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


@@ -30,41 +31,41 @@
 
 %{
 #include "system.h"
 
 %{
 #include "system.h"

-#include "muscle_tab.h"
+
+#include "complain.h"
+#include "conflicts.h"

 #include "files.h"
 #include "getargs.h"
 #include "files.h"
 #include "getargs.h"

-#include "output.h"

 #include "gram.h"
 #include "gram.h"

+#include "muscle_tab.h"
+#include "output.h"

 #include "reader.h"
 #include "reader.h"

-#include "conflicts.h"
+#include "symlist.h"

 
 

-/* Produce verbose parse errors.  */
+/* Produce verbose syntax errors.  */

 #define YYERROR_VERBOSE 1
 
 #define YYERROR_VERBOSE 1
 

-/* Pass the control structure to YYPARSE and YYLEX. */
-#define YYPARSE_PARAM gram_control
-#define YYLEX_PARAM gram_control
-/* YYPARSE receives GRAM_CONTROL as a void *.  Provide a
-   correctly typed access to it.  */
-#define yycontrol ((gram_control_t *) gram_control)
+#define YYLLOC_DEFAULT(Current, Rhs, N)  (Current) = lloc_default (Rhs, N)
+static YYLTYPE lloc_default (YYLTYPE const *, int);

 
 

-/* Request detailed parse error messages, and pass them to
-   GRAM_ERROR. */
+/* Request detailed syntax error messages, and pass them to GRAM_ERROR.
+   FIXME: depends on the undocumented availability of YYLLOC.  */

 #undef  yyerror
 #define yyerror(Msg) \
 #undef  yyerror
 #define yyerror(Msg) \

-        gram_error (yycontrol, &yylloc, Msg)
+        gram_error (&yylloc, Msg)
+static void gram_error (location const *, char const *);

 
 

-/* When debugging our pure parser, we want to see values and locations
-   of the tokens.  */

 #define YYPRINT(File, Type, Value) \
 #define YYPRINT(File, Type, Value) \

-        yyprint (File, &yylloc, Type, &Value)
-static void yyprint (FILE *file, const location_t *loc,
-                     int type, const yystype *value);
+       print_token_value (File, Type, &Value)
+static void print_token_value (FILE *, int, YYSTYPE const *);
+
+static void add_param (char const *, char *, location);

 
 symbol_class current_class = unknown_sym;
 
 symbol_class current_class = unknown_sym;

-char *current_type = 0;
-symbol_t *current_lhs;
-associativity current_assoc;
+uniqstr current_type = 0;
+symbol *current_lhs;
+location current_lhs_location;
+assoc current_assoc;

 int current_prec = 0;
 %}
 
 int current_prec = 0;
 %}
 


@@ -72,68 +73,93 @@ int current_prec = 0;
 /* Only NUMBERS have a value.  */
 %union
 {
 /* Only NUMBERS have a value.  */
 %union
 {

-  symbol_t *symbol;
+  symbol *symbol;
+  symbol_list *list;

   int integer;
   int integer;

-  char *string;
-  associativity assoc;
+  char *chars;
+  assoc assoc;
+  uniqstr uniqstr;

 };
 
 };
 

-/* Define the tokens together with there human representation. */
-%token GRAM_EOF 0 "end of string"
-%token STRING CHARACTER
-%token INT
-
-%token PERCENT_TOKEN "%token"
-%token PERCENT_NTERM "%nterm"
-%token PERCENT_TYPE  "%type"
-%token PERCENT_UNION "%union"
-%token PERCENT_EXPECT "%expect"
-%token PERCENT_START "%start"
-%token PERCENT_PREC     "%prec"
-%token PERCENT_VERBOSE  "%verbose"
-%token PERCENT_ERROR_VERBOSE "%error-verbose"
-
-%token PERCENT_OUTPUT "%output"
-%token PERCENT_FILE_PREFIX "%file-prefix"
-%token PERCENT_NAME_PREFIX "%name-prefix"
-
-%token PERCENT_DEFINE "%define"
-%token PERCENT_PURE_PARSER "%pure-parser"
-
-%token PERCENT_DEFINES "%defines"
-
-%token PERCENT_YACC "%yacc"
-
-%token PERCENT_DEBUG "%debug"
-%token PERCENT_LOCATIONS "%locations"
-%token PERCENT_NO_LINES "%no-lines"
-%token PERCENT_SKELETON "%skeleton"
-%token PERCENT_TOKEN_TABLE "%token-table"
-
-%token TYPE
-%token EQUAL "="
-%token SEMICOLON ";"
-%token COLON ":"
-%token PIPE "|"
-%token ID "identifier"
-%token PERCENT_PERCENT "%%"
-%token PROLOGUE EPILOGUE
-%token BRACED_CODE
+/* Define the tokens together with their human representation.  */
+%token GRAM_EOF 0 "end of file"
+%token STRING     "string"
+%token INT        "integer"
+
+%token PERCENT_TOKEN       "%token"
+%token PERCENT_NTERM       "%nterm"
+
+%token PERCENT_TYPE        "%type"
+%token PERCENT_DESTRUCTOR  "%destructor {...}"
+%token PERCENT_PRINTER     "%printer {...}"
+
+%token PERCENT_UNION       "%union {...}"
+
+%token PERCENT_LEFT        "%left"
+%token PERCENT_RIGHT       "%right"
+%token PERCENT_NONASSOC    "%nonassoc"
+
+%token PERCENT_PREC          "%prec"
+%token PERCENT_DPREC         "%dprec"
+%token PERCENT_MERGE         "%merge"
+
+
+/*----------------------.
+| Global Declarations.  |
+`----------------------*/
+
+%token
+  PERCENT_DEBUG         "%debug"
+  PERCENT_DEFINE        "%define"
+  PERCENT_DEFINES       "%defines"
+  PERCENT_ERROR_VERBOSE "%error-verbose"
+  PERCENT_EXPECT        "%expect"
+  PERCENT_FILE_PREFIX   "%file-prefix"
+  PERCENT_GLR_PARSER    "%glr-parser"
+  PERCENT_LEX_PARAM     "%lex-param {...}"
+  PERCENT_LOCATIONS     "%locations"
+  PERCENT_NAME_PREFIX   "%name-prefix"
+  PERCENT_NO_LINES      "%no-lines"
+  PERCENT_NONDETERMINISTIC_PARSER    "%nondeterministic-parser"
+  PERCENT_OUTPUT        "%output"
+  PERCENT_PARSE_PARAM   "%parse-param {...}"
+  PERCENT_PURE_PARSER   "%pure-parser"
+  PERCENT_SKELETON      "%skeleton"
+  PERCENT_START         "%start"
+  PERCENT_TOKEN_TABLE   "%token-table"
+  PERCENT_VERBOSE       "%verbose"
+  PERCENT_YACC          "%yacc"
+;

 
 

-%type <string> CHARACTER TYPE STRING string_content
-               BRACED_CODE PROLOGUE EPILOGUE epilogue.opt action
+%token TYPE            "type"
+%token EQUAL           "="
+%token SEMICOLON       ";"
+%token PIPE            "|"
+%token ID              "identifier"
+%token ID_COLON        "identifier:"
+%token PERCENT_PERCENT "%%"
+%token PROLOGUE        "%{...%}"
+%token EPILOGUE        "epilogue"
+%token BRACED_CODE     "{...}"
+
+
+%type <chars> STRING string_content
+             "%destructor {...}"
+             "%lex-param {...}"
+             "%parse-param {...}"
+             "%printer {...}"
+             "%union {...}"
+             BRACED_CODE action
+             PROLOGUE EPILOGUE
+%type <uniqstr> TYPE

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

-%type <symbol> ID symbol string_as_id
+%type <symbol> ID ID_COLON symbol string_as_id

 %type <assoc> precedence_declarator
 %type <assoc> precedence_declarator

-
+%type <list>  symbols.1

 %%
 
 %%
 

-input: { LOCATION_RESET (yylloc); }
+input:

   declarations "%%" grammar epilogue.opt
   declarations "%%" grammar epilogue.opt

-    {
-      yycontrol->errcode = 0;
-      epilogue_set ($5, @5);
-    }

 ;
 
 
 ;
 
 


@@ -143,7 +169,7 @@ input: { LOCATION_RESET (yylloc); }
 
 declarations:
   /* Nothing */
 
 declarations:
   /* Nothing */

-| declarations declaration semi_colon.opt
+| declarations declaration

 ;
 
 declaration:
 ;
 
 declaration:


@@ -155,15 +181,21 @@ declaration:
 | "%error-verbose"                         { error_verbose = 1; }
 | "%expect" INT                            { expected_conflicts = $2; }
 | "%file-prefix" "=" string_content        { spec_file_prefix = $3; }
 | "%error-verbose"                         { error_verbose = 1; }
 | "%expect" INT                            { expected_conflicts = $2; }
 | "%file-prefix" "=" string_content        { spec_file_prefix = $3; }

+| "%glr-parser"                           { nondeterministic_parser = true;
+                                             glr_parser = true; }
+| "%lex-param {...}"                      { add_param ("lex_param", $1, @1); }

 | "%locations"                             { locations_flag = 1; }
 | "%name-prefix" "=" string_content        { spec_name_prefix = $3; }
 | "%no-lines"                              { no_lines_flag = 1; }
 | "%locations"                             { locations_flag = 1; }
 | "%name-prefix" "=" string_content        { spec_name_prefix = $3; }
 | "%no-lines"                              { no_lines_flag = 1; }

+| "%nondeterministic-parser"              { nondeterministic_parser = true; }

 | "%output" "=" string_content             { spec_outfile = $3; }
 | "%output" "=" string_content             { spec_outfile = $3; }

-| "%pure-parser"                           { pure_parser = 1; }
+| "%parse-param {...}"                  { add_param ("parse_param", $1, @1); }
+| "%pure-parser"                           { pure_parser = true; }

 | "%skeleton" string_content               { skeleton = $2; }
 | "%token-table"                           { token_table_flag = 1; }
 | "%skeleton" string_content               { skeleton = $2; }
 | "%token-table"                           { token_table_flag = 1; }

-| "%verbose"                               { report_flag = 1; }
+| "%verbose"                               { report_flag = report_states; }

 | "%yacc"                                  { yacc_flag = 1; }
 | "%yacc"                                  { yacc_flag = 1; }

+| ";"

 ;
 
 grammar_declaration:
 ;
 
 grammar_declaration:


@@ -171,13 +203,27 @@ grammar_declaration:
 | symbol_declaration
 | "%start" symbol
     {
 | symbol_declaration
 | "%start" symbol
     {

-      grammar_start_symbol_set ($2);
+      grammar_start_symbol_set ($2, @2);

     }
     }

-| "%union" BRACED_CODE
+| "%union {...}"

     {
       typed = 1;
     {
       typed = 1;

-      MUSCLE_INSERT_INT ("stype_line", @2.first_line);
-      muscle_insert ("stype", $2);
+      MUSCLE_INSERT_INT ("stype_line", @1.start.line);
+      muscle_insert ("stype", $1);
+    }
+| "%destructor {...}" symbols.1
+    {
+      symbol_list *list;
+      for (list = $2; list; list = list->next)
+       symbol_destructor_set (list->sym, $1, @1);
+      symbol_list_free ($2);
+    }
+| "%printer {...}" symbols.1
+    {
+      symbol_list *list;
+      for (list = $2; list; list = list->next)
+       symbol_printer_set (list->sym, $1, list->location);
+      symbol_list_free ($2);

     }
 ;
 
     }
 ;
 


@@ -192,22 +238,30 @@ symbol_declaration:
       current_class = unknown_sym;
       current_type = NULL;
     }
       current_class = unknown_sym;
       current_type = NULL;
     }

-| "%type" TYPE {current_type = $2; } nterms_to_type.1
+| "%type" TYPE symbols.1

     {
     {

-      current_type = NULL;
+      symbol_list *list;
+      for (list = $3; list; list = list->next)
+       symbol_type_set (list->sym, $2, @2);
+      symbol_list_free ($3);

     }
 ;
 
 precedence_declaration:
     }
 ;
 
 precedence_declaration:

-  precedence_declarator type.opt
-    { current_assoc = $1; ++current_prec; }
-  terms_to_prec.1
-    { current_assoc = non_assoc; current_type = NULL; }
+  precedence_declarator type.opt symbols.1
+    {
+      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_list_free ($3);
+      current_type = NULL;
+    }

 ;
 
 ;
 

-%token PERCENT_LEFT     "%left";
-%token PERCENT_RIGHT    "%right";
-%token PERCENT_NONASSOC "%nonassoc";

 precedence_declarator:
   "%left"     { $$ = left_assoc; }
 | "%right"    { $$ = right_assoc; }
 precedence_declarator:
   "%left"     { $$ = left_assoc; }
 | "%right"    { $$ = right_assoc; }


@@ -215,28 +269,15 @@ precedence_declarator:
 ;
 
 type.opt:
 ;
 
 type.opt:

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

 | TYPE           { current_type = $1; }
 ;
 
 /* One or more nonterminals to be %typed. */
 | TYPE           { current_type = $1; }
 ;
 
 /* One or more nonterminals to be %typed. */

-nterms_to_type.1:
-  ID                   { symbol_type_set ($1, current_type); }
-| nterms_to_type.1 ID  { symbol_type_set ($2, current_type); }
-;

 
 

-/* One or more symbols to be given a precedence/associativity.  */
-terms_to_prec.1:
-  symbol
-    {
-      symbol_type_set ($1, current_type);
-      symbol_precedence_set ($1, current_prec, current_assoc);
-    }
-| terms_to_prec.1 symbol
-    {
-      symbol_type_set ($2, current_type);
-      symbol_precedence_set ($2, current_prec, current_assoc);
-    }
+symbols.1:
+  symbol            { $$ = symbol_list_new ($1, @1); }
+| symbols.1 symbol  { $$ = symbol_list_prepend ($1, $2, @2); }

 ;
 
 /* One token definition.  */
 ;
 
 /* One token definition.  */


@@ -247,36 +288,34 @@ symbol_def:
      }
 | ID
      {
      }
 | ID
      {

-       symbol_class_set ($1, current_class);
-       symbol_type_set ($1, current_type);
+       symbol_class_set ($1, current_class, @1);
+       symbol_type_set ($1, current_type, @1);

      }
 | ID INT
     {
      }
 | ID INT
     {

-      symbol_class_set ($1, current_class);
-      symbol_type_set ($1, current_type);
-      symbol_user_token_number_set ($1, $2);
+      symbol_class_set ($1, current_class, @1);
+      symbol_type_set ($1, current_type, @1);
+      symbol_user_token_number_set ($1, $2, @2);

     }
 | ID string_as_id
     {
     }
 | ID string_as_id
     {

-      symbol_class_set ($1, current_class);
-      symbol_type_set ($1, current_type);
-      symbol_make_alias ($1, $2);
+      symbol_class_set ($1, current_class, @1);
+      symbol_type_set ($1, current_type, @1);
+      symbol_make_alias ($1, $2, @$);

     }
 | ID INT string_as_id
     {
     }
 | ID INT string_as_id
     {

-      symbol_class_set ($1, current_class);
-      symbol_type_set ($1, current_type);
-      symbol_user_token_number_set ($1, $2);
-      symbol_make_alias ($1, $3);
+      symbol_class_set ($1, current_class, @1);
+      symbol_type_set ($1, current_type, @1);
+      symbol_user_token_number_set ($1, $2, @2);
+      symbol_make_alias ($1, $3, @$);

     }
 ;
 
 /* One or more symbol definitions. */
 symbol_defs.1:
   symbol_def
     }
 ;
 
 /* One or more symbol definitions. */
 symbol_defs.1:
   symbol_def

-    {;}

 | symbol_defs.1 symbol_def
 | symbol_defs.1 symbol_def

-    {;}

 ;
 
 
 ;
 
 


@@ -290,38 +329,48 @@ grammar:
 ;
 
 /* As a Bison extension, one can use the grammar declarations in the
 ;
 
 /* As a Bison extension, one can use the grammar declarations in the

-   body of the grammar.  But to remain LALR(1), they must be ended
-   with a semi-colon.  */
+   body of the grammar.  */

 rules_or_grammar_declaration:
   rules
 | grammar_declaration ";"
 rules_or_grammar_declaration:
   rules
 | grammar_declaration ";"

+    {
+      if (yacc_flag)
+       complain_at (@$, _("POSIX forbids declarations in the grammar"));
+    }
+| error ";"
+    {
+      yyerrok;
+    }

 ;
 
 rules:
 ;
 
 rules:

-  ID ":" { current_lhs = $1; } rhses.1 ";"
-    {;}
+  ID_COLON { current_lhs = $1; current_lhs_location = @1; } rhses.1

 ;
 
 rhses.1:
 ;
 
 rhses.1:

-  rhs                { grammar_rule_end (); }
-| rhses.1 "|" rhs    { grammar_rule_end (); }
+  rhs                { grammar_rule_end (@1); }
+| rhses.1 "|" rhs    { grammar_rule_end (@3); }
+| rhses.1 ";"

 ;
 
 rhs:
   /* Nothing.  */
 ;
 
 rhs:
   /* Nothing.  */

-    { grammar_rule_begin (current_lhs); }
+    { grammar_rule_begin (current_lhs, current_lhs_location); }

 | rhs symbol
 | rhs symbol

-    { grammar_current_rule_symbol_append ($2); }
+    { grammar_current_rule_symbol_append ($2, @2); }

 | rhs action
 | rhs action

-    { grammar_current_rule_action_append ($2, @2.first_line); }
+    { grammar_current_rule_action_append ($2, @2); }

 | rhs "%prec" symbol
 | rhs "%prec" symbol

-    { grammar_current_rule_prec_set ($3); }
+    { grammar_current_rule_prec_set ($3, @3); }
+| rhs "%dprec" INT
+    { grammar_current_rule_dprec_set ($3, @3); }
+| rhs "%merge" TYPE
+    { grammar_current_rule_merge_set ($3, @3); }

 ;
 
 symbol:
   ID              { $$ = $1; }
 | string_as_id    { $$ = $1; }
 ;
 
 symbol:
   ID              { $$ = $1; }
 | string_as_id    { $$ = $1; }

-| CHARACTER       { $$ = getsym ($1); }

 ;
 
 action:
 ;
 
 action:


@@ -333,8 +382,8 @@ action:
 string_as_id:
   STRING
     {
 string_as_id:
   STRING
     {

-      $$ = getsym ($1);
-      symbol_class_set ($$, token_sym);
+      $$ = symbol_get ($1, @1);
+      symbol_class_set ($$, token_sym, @1);

     }
 ;
 
     }
 ;
 


@@ -349,37 +398,97 @@ string_content:
 
 epilogue.opt:
   /* Nothing.  */
 
 epilogue.opt:
   /* Nothing.  */

-    {
-      $$ = xstrdup ("");
-    }

 | "%%" EPILOGUE
     {
 | "%%" EPILOGUE
     {

-      $$ = $2;
+      epilogue_augment ($2, @2);
+      scanner_last_string_free ();

     }
 ;
 
     }
 ;
 

-semi_colon.opt:
-  /* Nothing.  */
-| ";"
-;

 %%
 %%

-/*------------------------------------------------------------------.
-| When debugging the parser, display tokens' locations and values.  |
-`------------------------------------------------------------------*/
+
+
+/* Return the location of the left-hand side of a rule whose
+   right-hand side is RHS[1] ... RHS[N].  Ignore empty nonterminals in
+   the right-hand side, and return an empty location equal to the end
+   boundary of RHS[0] if the right-hand side is empty.  */
+
+static YYLTYPE
+lloc_default (YYLTYPE const *rhs, int n)
+{
+  int i;
+  YYLTYPE loc;
+  loc.start = loc.end = rhs[n].end;
+
+  /* Ignore empty nonterminals the start of the the right-hand side.
+     Do not bother to ignore them at the end of the right-hand side,
+     since empty nonterminals have the same end as their predecessors.  */
+  for (i = 1; i <= n; i++)
+    if (! equal_boundaries (rhs[i].start, rhs[i].end))
+      {
+       loc.start = rhs[i].start;
+       break;
+      }
+
+  return loc;
+}
+
+
+/* Add a lex-param or a parse-param (depending on TYPE) with
+   declaration DECL and location LOC.  */

 
 static void
 
 static void

-yyprint (FILE *file,
-         const location_t *loc, int type, const yystype *value)
+add_param (char const *type, char *decl, location loc)

 {
 {

-  fputs (" (", file);
-  LOCATION_PRINT (file, *loc);
-  fputs (")", file);
-  switch (type)
+  static char const alphanum[] =
+    "0123456789"
+    "abcdefghijklmnopqrstuvwxyz"
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+    "_";
+  char const *alpha = alphanum + 10;
+  char const *name_start = NULL;
+  char *p;
+
+  for (p = decl; *p; p++)
+    if ((p == decl || ! strchr (alphanum, p[-1])) && strchr (alpha, p[0]))
+      name_start = p;
+
+  /* Strip the surrounding '{' and '}'.  */
+  decl++;
+  p[-1] = '\0';
+
+  if (! name_start)
+    complain_at (loc, _("missing identifier in parameter declaration"));
+  else

     {
     {

-    case CHARACTER:
-      fprintf (file, " = '%s'", value->string);
-      break;
+      char *name;
+      size_t name_len;
+
+      for (name_len = 1;
+          name_start[name_len] && strchr (alphanum, name_start[name_len]);
+          name_len++)
+       continue;
+
+      name = xmalloc (name_len + 1);
+      memcpy (name, name_start, name_len);
+      name[name_len] = '\0';
+      muscle_pair_list_grow (type, decl, name);
+      free (name);
+    }
+
+  scanner_last_string_free ();
+}

 
 

+/*----------------------------------------------------.
+| When debugging the parser, display tokens' values.  |
+`----------------------------------------------------*/
+
+static void
+print_token_value (FILE *file, int type, YYSTYPE const *value)
+{
+  fputc (' ', file);
+  switch (type)
+    {

     case ID:
       fprintf (file, " = %s", value->symbol->tag);
       break;
     case ID:
       fprintf (file, " = %s", value->symbol->tag);
       break;


@@ -389,25 +498,38 @@ yyprint (FILE *file,
       break;
 
     case STRING:
       break;
 
     case STRING:

-      fprintf (file, " = \"%s\"", value->string);
+      fprintf (file, " = \"%s\"", value->chars);

       break;
 
     case TYPE:
       break;
 
     case TYPE:

-      fprintf (file, " = <%s>", value->string);
+      fprintf (file, " = <%s>", value->uniqstr);

       break;
 
     case BRACED_CODE:
       break;
 
     case BRACED_CODE:

+    case PERCENT_DESTRUCTOR:
+    case PERCENT_LEX_PARAM:
+    case PERCENT_PARSE_PARAM:
+    case PERCENT_PRINTER:
+    case PERCENT_UNION:

     case PROLOGUE:
     case EPILOGUE:
     case PROLOGUE:
     case EPILOGUE:

-      fprintf (file, " = {{ %s }}", value->string);
+      fprintf (file, " = {{ %s }}", value->chars);
+      break;
+
+    default:
+      fprintf (file, "unknown token type");

       break;
     }
 }
 
       break;
     }
 }
 

-void
-gram_error (gram_control_t *control ATTRIBUTE_UNUSED,
-           location_t *yylloc, const char *msg)
+static void
+gram_error (location const *loc, char const *msg)
+{
+  complain_at (*loc, "%s", msg);
+}
+
+char const *
+token_name (int type)

 {
 {

-  LOCATION_PRINT (stderr, *yylloc);
-  fprintf (stderr, ": %s\n", msg);
+  return yytname[type];

 }
 }