data/c.m4 - bison - Git at Google

                                                             -*- Autoconf -*-

 # C M4 Macros for Bison.

 # Copyright (C) 2002, 2004-2012 Free Software Foundation, Inc.

 # 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
 # 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,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # 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, see <http://www.gnu.org/licenses/>.


 # b4_tocpp(STRING)
 # ----------------
 # Convert STRING into a valid C macro name.
 m4_define([b4_tocpp],
 [m4_toupper(m4_bpatsubst(m4_quote($1), [[^a-zA-Z0-9]+], [_]))])


 # b4_cpp_guard(FILE)
 # ------------------
 # A valid C macro name to use as a CPP header guard for FILE.
 m4_define([b4_cpp_guard],
 [b4_tocpp(m4_defn([b4_prefix])/[$1])])


 # b4_cpp_guard_open(FILE)
 # b4_cpp_guard_close(FILE)
 # ------------------------
 # Open/close CPP inclusion guards for FILE.
 m4_define([b4_cpp_guard_open],
 [#ifndef b4_cpp_guard([$1])
 # define b4_cpp_guard([$1])])

 m4_define([b4_cpp_guard_close],
 [#endif b4_comment([!b4_cpp_guard([$1])])])


 ## ---------------- ##
 ## Identification.  ##
 ## ---------------- ##

 # b4_comment_(TEXT, OPEN, CONTINUE, END)
 # -------------------------------------
 # Put TEXT in comment.  Avoid trailing spaces: don't indent empty lines.
 # Avoid adding indentation to the first line, as the indentation comes
 # from OPEN.  That's why we don't patsubst([$1], [^\(.\)], [   \1]).
 #
 # Prefix all the output lines with PREFIX.
 m4_define([b4_comment_], [$2[]m4_bpatsubst([$1], [
 \(.\)], [
 $3\1])$4])


 # b4_c_comment(TEXT, [PREFIX])
 # ----------------------------
 # Put TEXT in comment.  Avoid trailing spaces: don't indent empty lines.
 # Avoid adding indentation to the first line, as the indentation comes
 # from "/*".  That's why we don't patsubst([$1], [^\(.\)], [   \1]).
 #
 # Prefix all the output lines with PREFIX.
 m4_define([b4_c_comment],
 [b4_comment_([$1], [$2/* ], [$2   ], [$2  */])])


 # b4_comment(TEXT, [PREFIX])
 # --------------------------
 # By default, C comments.
 m4_define([b4_comment], [b4_c_comment($@)])


 # b4_identification
 # -----------------
 # Depends on individual skeletons to define b4_pure_flag, b4_push_flag, or
 # b4_pull_flag if they use the values of the %define variables api.pure or
 # api.push-pull.
 m4_define([b4_identification],
 [[/* Identify Bison output.  */
 #define YYBISON 1

 /* Bison version.  */
 #define YYBISON_VERSION "]b4_version["

 /* Skeleton name.  */
 #define YYSKELETON_NAME ]b4_skeleton[]m4_ifdef([b4_pure_flag], [[

 /* Pure parsers.  */
 #define YYPURE ]b4_pure_flag])[]m4_ifdef([b4_push_flag], [[

 /* Push parsers.  */
 #define YYPUSH ]b4_push_flag])[]m4_ifdef([b4_pull_flag], [[

 /* Pull parsers.  */
 #define YYPULL ]b4_pull_flag])[
 ]])


 ## ---------------- ##
 ## Default values.  ##
 ## ---------------- ##

 # b4_api_prefix, b4_api_PREFIX
 # ----------------------------
 # Corresponds to %define api.prefix
 b4_percent_define_default([[api.prefix]], [[yy]])
 m4_define([b4_api_prefix],
 [b4_percent_define_get([[api.prefix]])])
 m4_define([b4_api_PREFIX],
 [m4_toupper(b4_api_prefix)])


 # b4_prefix
 # ---------
 # If the %name-prefix is not given, it is api.prefix.
 m4_define_default([b4_prefix], [b4_api_prefix])

 # If the %union is not named, its name is YYSTYPE.
 m4_define_default([b4_union_name], [b4_api_PREFIX[]STYPE])


 ## ------------------------ ##
 ## Pure/impure interfaces.  ##
 ## ------------------------ ##

 # b4_user_args
 # ------------
 m4_define([b4_user_args],
 [m4_ifset([b4_parse_param], [, b4_c_args(b4_parse_param)])])


 # b4_parse_param
 # --------------
 # If defined, b4_parse_param arrives double quoted, but below we prefer
 # it to be single quoted.
 m4_define([b4_parse_param],
 b4_parse_param)


 # b4_parse_param_for(DECL, FORMAL, BODY)
 # ---------------------------------------
 # Iterate over the user parameters, binding the declaration to DECL,
 # the formal name to FORMAL, and evaluating the BODY.
 m4_define([b4_parse_param_for],
 [m4_foreach([$1_$2], m4_defn([b4_parse_param]),
 [m4_pushdef([$1], m4_unquote(m4_car($1_$2)))dnl
 m4_pushdef([$2], m4_shift($1_$2))dnl
 $3[]dnl
 m4_popdef([$2])dnl
 m4_popdef([$1])dnl
 ])])

 # b4_parse_param_use([VAL], [LOC])
 # --------------------------------
 # `YYUSE' VAL, LOC if locations are enabled, and all the parse-params.
 m4_define([b4_parse_param_use],
 [m4_ifvaln([$1], [  YYUSE([$1]);])dnl
 b4_locations_if([m4_ifvaln([$2], [  YYUSE ([$2]);])])dnl
 b4_parse_param_for([Decl], [Formal], [  YYUSE (Formal);
 ])dnl
 ])


 ## ------------ ##
 ## Data Types.  ##
 ## ------------ ##

 # b4_int_type(MIN, MAX)
 # ---------------------
 # Return the smallest int type able to handle numbers ranging from
 # MIN to MAX (included).
 m4_define([b4_int_type],
 [m4_if(b4_ints_in($@,      [0],   [255]), [1], [unsigned char],
        b4_ints_in($@,   [-128],   [127]), [1], [signed char],

        b4_ints_in($@,      [0], [65535]), [1], [unsigned short int],
        b4_ints_in($@, [-32768], [32767]), [1], [short int],

        m4_eval([0 <= $1]),                [1], [unsigned int],

                                                [int])])


 # b4_int_type_for(NAME)
 # ---------------------
 # Return the smallest int type able to handle numbers ranging from
 # `NAME_min' to `NAME_max' (included).
 m4_define([b4_int_type_for],
 [b4_int_type($1_min, $1_max)])


 # b4_table_value_equals(TABLE, VALUE, LITERAL)
 # --------------------------------------------
 # Without inducing a comparison warning from the compiler, check if the
 # literal value LITERAL equals VALUE from table TABLE, which must have
 # TABLE_min and TABLE_max defined.  YYID must be defined as an identity
 # function that suppresses warnings about constant conditions.
 m4_define([b4_table_value_equals],
 [m4_if(m4_eval($3 < m4_indir([b4_]$1[_min])
                || m4_indir([b4_]$1[_max]) < $3), [1],
        [[YYID (0)]],
        [[((]$2[) == (]$3[))]])])


 ## ---------##
 ## Values.  ##
 ## ---------##


 # b4_null_define
 # --------------
 # Portability issues: define a YY_NULL appropriate for the current
 # language (C, C++98, or C++11).
 m4_define([b4_null_define],
 [# ifndef YY_NULL
 #  if defined __cplusplus && 201103L <= __cplusplus
 #   define YY_NULL nullptr
 #  else
 #   define YY_NULL 0
 #  endif
 # endif[]dnl
 ])


 # b4_null
 # -------
 # Return a null pointer constant.
 m4_define([b4_null], [YY_NULL])

 # b4_integral_parser_table_define(TABLE-NAME, CONTENT, COMMENT)
 # -------------------------------------------------------------
 # Define "yy<TABLE-NAME>" which contents is CONTENT.
 m4_define([b4_integral_parser_table_define],
 [m4_ifvaln([$3], [b4_c_comment([$3], [  ])])dnl
 static const b4_int_type_for([$2]) yy$1[[]] =
 {
   $2
 };dnl
 ])


 ## ------------------------- ##
 ## Assigning token numbers.  ##
 ## ------------------------- ##

 # b4_token_define(TOKEN-NUM)
 # --------------------------
 # Output the definition of this token as #define.
 m4_define([b4_token_define],
 [b4_token_format([#define %s %s], [$1])])

 # b4_token_defines
 # ----------------
 # Output the definition of the tokens.
 m4_define([b4_token_defines],
 [b4_any_token_visible_if([/* Tokens.  */
 m4_join([
 ], b4_symbol_map([b4_token_define]))])])


 # b4_token_enum(TOKEN-NUM)
 # ------------------------
 # Output the definition of this token as an enum.
 m4_define([b4_token_enum],
 [b4_token_format([  %s = %s], [$1])])


 # b4_token_enums
 # --------------
 # Output the definition of the tokens (if there are) as enums.
 m4_define([b4_token_enums],
 [b4_any_token_visible_if([[/* Tokens.  */
 #ifndef ]b4_api_PREFIX[TOKENTYPE
 # define ]b4_api_PREFIX[TOKENTYPE
   /* Put the tokens into the symbol table, so that GDB and other debuggers
      know about them.  */
   enum ]b4_api_prefix[tokentype {
   ]m4_join([,
   ],
             b4_symbol_map([b4_token_enum]))[
   };
 #endif
 ]])])


 # b4_token_enums_defines
 # ----------------------
 # Output the definition of the tokens (if there are any) as enums and,
 # if POSIX Yacc is enabled, as #defines.
 m4_define([b4_token_enums_defines],
 [b4_token_enums[]b4_yacc_if([b4_token_defines])])


 ## ----------------- ##
 ## Semantic Values.  ##
 ## ----------------- ##


 # b4_symbol_value(VAL, [TYPE])
 # ----------------------------
 # Given a semantic value VAL ($$, $1 etc.), extract its value of type
 # TYPE if TYPE is given, otherwise just return VAL.  The result can be
 # used safetly, it is put in parens to avoid nasty precedence issues.
 # TYPE is *not* put in braces, provide some if needed.
 m4_define([b4_symbol_value],
 [($1[]m4_ifval([$2], [.$2]))])


 ## --------------------------------------------- ##
 ## Defining C functions in both K&R and ANSI-C.  ##
 ## --------------------------------------------- ##


 # b4_modern_c
 # -----------
 # A predicate useful in #if to determine whether C is ancient or modern.
 #
 # If __STDC__ is defined, the compiler is modern.  IBM xlc 7.0 when run
 # as 'cc' doesn't define __STDC__ (or __STDC_VERSION__) for pedantic
 # reasons, but it defines __C99__FUNC__ so check that as well.
 # Microsoft C normally doesn't define these macros, but it defines _MSC_VER.
 # Consider a C++ compiler to be modern if it defines __cplusplus.
 #
 m4_define([b4_c_modern],
   [[(defined __STDC__ || defined __C99__FUNC__ \
      || defined __cplusplus || defined _MSC_VER)]])

 # b4_c_function_def(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
 # ----------------------------------------------------------
 # Declare the function NAME.
 m4_define([b4_c_function_def],
 [#if b4_c_modern
 b4_c_ansi_function_def($@)
 #else
 $2
 $1 (b4_c_knr_formal_names(m4_shift2($@)))
 b4_c_knr_formal_decls(m4_shift2($@))
 #endif[]dnl
 ])


 # b4_c_ansi_function_def(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
 # ---------------------------------------------------------------
 # Declare the function NAME in ANSI.
 m4_define([b4_c_ansi_function_def],
 [$2
 $1 (b4_c_ansi_formals(m4_shift2($@)))[]dnl
 ])


 # b4_c_ansi_formals([DECL1, NAME1], ...)
 # --------------------------------------
 # Output the arguments ANSI-C definition.
 m4_define([b4_c_ansi_formals],
 [m4_if([$#], [0], [void],
        [$#$1], [1], [void],
                [m4_map_sep([b4_c_ansi_formal], [, ], [$@])])])

 m4_define([b4_c_ansi_formal],
 [$1])


 # b4_c_knr_formal_names([DECL1, NAME1], ...)
 # ------------------------------------------
 # Output the argument names.
 m4_define([b4_c_knr_formal_names],
 [m4_map_sep([b4_c_knr_formal_name], [, ], [$@])])

 m4_define([b4_c_knr_formal_name],
 [$2])


 # b4_c_knr_formal_decls([DECL1, NAME1], ...)
 # ------------------------------------------
 # Output the K&R argument declarations.
 m4_define([b4_c_knr_formal_decls],
 [m4_map_sep([b4_c_knr_formal_decl],
             [
 ],
             [$@])])

 m4_define([b4_c_knr_formal_decl],
 [    $1;])


 ## ------------------------------------------------------------ ##
 ## Declaring (prototyping) C functions in both K&R and ANSI-C.  ##
 ## ------------------------------------------------------------ ##


 # b4_c_function_decl(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
 # -----------------------------------------------------------
 # Declare the function NAME.
 m4_define([b4_c_function_decl],
 [#if b4_c_modern
 b4_c_ansi_function_decl($@)
 #else
 $2 $1 ();
 #endif[]dnl
 ])


 # b4_c_ansi_function_decl(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
 # ----------------------------------------------------------------
 # Declare the function NAME.
 m4_define([b4_c_ansi_function_decl],
 [$2 $1 (b4_c_ansi_formals(m4_shift2($@)));[]dnl
 ])


 ## --------------------- ##
 ## Calling C functions.  ##
 ## --------------------- ##


 # b4_c_function_call(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
 # -----------------------------------------------------------
 # Call the function NAME with arguments NAME1, NAME2 etc.
 m4_define([b4_c_function_call],
 [$1 (b4_c_args(m4_shift2($@)))[]dnl
 ])


 # b4_c_args([DECL1, NAME1], ...)
 # ------------------------------
 # Output the arguments NAME1, NAME2...
 m4_define([b4_c_args],
 [m4_map_sep([b4_c_arg], [, ], [$@])])

 m4_define([b4_c_arg],
 [$2])


 ## ----------- ##
 ## Synclines.  ##
 ## ----------- ##

 # b4_sync_start(LINE, FILE)
 # -----------------------
 m4_define([b4_sync_start], [[#]line $1 $2])


 ## -------------- ##
 ## User actions.  ##
 ## -------------- ##

 # b4_case(LABEL, STATEMENTS)
 # --------------------------
 m4_define([b4_case],
 [  case $1:
 $2
 b4_syncline([@oline@], [@ofile@])
     break;])


 # b4_predicate_case(LABEL, CONDITIONS)
 # ------------------------------------
 m4_define([b4_predicate_case],
 [  case $1:
     if (! ($2)) YYERROR;
 b4_syncline([@oline@], [@ofile@])
     break;])


 # b4_yydestruct_generate(FUNCTION-DECLARATOR)
 # -------------------------------------------
 # Generate the "yydestruct" function, which declaration is issued using
 # FUNCTION-DECLARATOR, which may be "b4_c_ansi_function_def" for ISO C
 # or "b4_c_function_def" for K&R.
 m4_define_default([b4_yydestruct_generate],
 [[/*-----------------------------------------------.
 | Release the memory associated to this symbol.  |
 `-----------------------------------------------*/

 /*ARGSUSED*/
 ]$1([yydestruct],
     [static void],
     [[const char *yymsg],    [yymsg]],
     [[int yytype],           [yytype]],
     [[YYSTYPE *yyvaluep],    [yyvaluep]][]dnl
 b4_locations_if(            [, [[YYLTYPE *yylocationp], [yylocationp]]])[]dnl
 m4_ifset([b4_parse_param], [, b4_parse_param]))[
 {
 ]b4_parse_param_use([yyvaluep], [yylocationp])dnl
 [  if (!yymsg)
     yymsg = "Deleting";
   YY_SYMBOL_PRINT (yymsg, yytype, yyvaluep, yylocationp);

   switch (yytype)
     {
 ]b4_symbol_foreach([b4_symbol_destructor])dnl
 [      default:
         break;
     }
 }]dnl
 ])


 # b4_yy_symbol_print_generate(FUNCTION-DECLARATOR)
 # ------------------------------------------------
 # Generate the "yy_symbol_print" function, which declaration is issued using
 # FUNCTION-DECLARATOR, which may be "b4_c_ansi_function_def" for ISO C
 # or "b4_c_function_def" for K&R.
 m4_define_default([b4_yy_symbol_print_generate],
 [[
 /*--------------------------------.
 | Print this symbol on YYOUTPUT.  |
 `--------------------------------*/

 /*ARGSUSED*/
 ]$1([yy_symbol_value_print],
     [static void],
                [[FILE *yyoutput],                       [yyoutput]],
                [[int yytype],                           [yytype]],
                [[YYSTYPE const * const yyvaluep],       [yyvaluep]][]dnl
 b4_locations_if([, [[YYLTYPE const * const yylocationp], [yylocationp]]])[]dnl
 m4_ifset([b4_parse_param], [, b4_parse_param]))[
 {
   FILE *yyo = yyoutput;
 ]b4_parse_param_use([yyo], [yylocationp])dnl
 [  if (!yyvaluep)
     return;]
 dnl glr.c does not feature yytoknum.
 m4_if(b4_skeleton, ["yacc.c"],
 [[# ifdef YYPRINT
   if (yytype < YYNTOKENS)
     YYPRINT (yyoutput, yytoknum[yytype], *yyvaluep);
 # endif
 ]])dnl
 [  switch (yytype)
     {
 ]b4_symbol_foreach([b4_symbol_printer])dnl
 [      default:
         break;
     }
 }


 /*--------------------------------.
 | Print this symbol on YYOUTPUT.  |
 `--------------------------------*/

 ]$1([yy_symbol_print],
     [static void],
                [[FILE *yyoutput],                       [yyoutput]],
                [[int yytype],                           [yytype]],
                [[YYSTYPE const * const yyvaluep],       [yyvaluep]][]dnl
 b4_locations_if([, [[YYLTYPE const * const yylocationp], [yylocationp]]])[]dnl
 m4_ifset([b4_parse_param], [, b4_parse_param]))[
 {
   if (yytype < YYNTOKENS)
     YYFPRINTF (yyoutput, "token %s (", yytname[yytype]);
   else
     YYFPRINTF (yyoutput, "nterm %s (", yytname[yytype]);

 ]b4_locations_if([  YY_LOCATION_PRINT (yyoutput, *yylocationp);
   YYFPRINTF (yyoutput, ": ");
 ])dnl
 [  yy_symbol_value_print (yyoutput, yytype, yyvaluep]dnl
 b4_locations_if([, yylocationp])[]b4_user_args[);
   YYFPRINTF (yyoutput, ")");
 }]dnl
 ])

 ## -------------- ##
 ## Declarations.  ##
 ## -------------- ##

 # b4_declare_yylstype
 # -------------------
 # Declarations that might either go into the header (if --defines) or
 # in the parser body.  Declare YYSTYPE/YYLTYPE, and yylval/yylloc.
 m4_define([b4_declare_yylstype],
 [[#if ! defined ]b4_api_PREFIX[STYPE && ! defined ]b4_api_PREFIX[STYPE_IS_DECLARED
 ]m4_ifdef([b4_stype],
 [[typedef union ]b4_union_name[
 {
 ]b4_user_stype[
 } ]b4_api_PREFIX[STYPE;
 # define ]b4_api_PREFIX[STYPE_IS_TRIVIAL 1]],
 [m4_if(b4_tag_seen_flag, 0,
 [[typedef int ]b4_api_PREFIX[STYPE;
 # define ]b4_api_PREFIX[STYPE_IS_TRIVIAL 1]])])[
 # define ]b4_api_prefix[stype ]b4_api_PREFIX[STYPE /* obsolescent; will be withdrawn */
 # define ]b4_api_PREFIX[STYPE_IS_DECLARED 1
 #endif]b4_locations_if([[

 #if ! defined ]b4_api_PREFIX[LTYPE && ! defined ]b4_api_PREFIX[LTYPE_IS_DECLARED
 typedef struct ]b4_api_PREFIX[LTYPE
 {
   int first_line;
   int first_column;
   int last_line;
   int last_column;
 } ]b4_api_PREFIX[LTYPE;
 # define ]b4_api_prefix[ltype ]b4_api_PREFIX[LTYPE /* obsolescent; will be withdrawn */
 # define ]b4_api_PREFIX[LTYPE_IS_DECLARED 1
 # define ]b4_api_PREFIX[LTYPE_IS_TRIVIAL 1
 #endif]])

 b4_pure_if([], [[extern ]b4_api_PREFIX[STYPE ]b4_prefix[lval;
 ]b4_locations_if([[extern ]b4_api_PREFIX[LTYPE ]b4_prefix[lloc;]])])[]dnl
 ])

 # b4_YYDEBUG_define
 # ------------------
 m4_define([b4_YYDEBUG_define],
 [[/* Enabling traces.  */
 ]m4_if(b4_api_prefix, [yy],
 [[#ifndef YYDEBUG
 # define YYDEBUG ]b4_parse_trace_if([1], [0])[
 #endif]],
 [[#ifndef ]b4_api_PREFIX[DEBUG
 # if defined YYDEBUG
 #if YYDEBUG
 #   define ]b4_api_PREFIX[DEBUG 1
 #  else
 #   define ]b4_api_PREFIX[DEBUG 0
 #  endif
 # else /* ! defined YYDEBUG */
 #  define ]b4_api_PREFIX[DEBUG ]b4_parse_trace_if([1], [0])[
 # endif /* ! defined ]b4_api_PREFIX[DEBUG */
 #endif  /* ! defined ]b4_api_PREFIX[DEBUG */]])[]dnl
 ])

 # b4_declare_yydebug
 # ------------------
 m4_define([b4_declare_yydebug],
 [b4_YYDEBUG_define[
 #if ]b4_api_PREFIX[DEBUG
 extern int ]b4_prefix[debug;
 #endif][]dnl
 ])

 # b4_yylloc_default_define
 # ------------------------
 # Define YYLLOC_DEFAULT.
 m4_define([b4_yylloc_default_define],
 [[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
    If N is 0, then set CURRENT to the empty location which ends
    the previous symbol: RHS[0] (always defined).  */

 #ifndef YYLLOC_DEFAULT
 # define YYLLOC_DEFAULT(Current, Rhs, N)                                \
     do                                                                  \
       if (YYID (N))                                                     \
         {                                                               \
           (Current).first_line   = YYRHSLOC (Rhs, 1).first_line;        \
           (Current).first_column = YYRHSLOC (Rhs, 1).first_column;      \
           (Current).last_line    = YYRHSLOC (Rhs, N).last_line;         \
           (Current).last_column  = YYRHSLOC (Rhs, N).last_column;       \
         }                                                               \
       else                                                              \
         {                                                               \
           (Current).first_line   = (Current).last_line   =              \
             YYRHSLOC (Rhs, 0).last_line;                                \
           (Current).first_column = (Current).last_column =              \
             YYRHSLOC (Rhs, 0).last_column;                              \
         }                                                               \
     while (YYID (0))
 #endif
 ]])
	-- Autoconf --

	# C M4 Macros for Bison.

	# Copyright (C) 2002, 2004-2012 Free Software Foundation, Inc.

	# 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
	# 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,
	# but WITHOUT ANY WARRANTY; without even the implied warranty of
	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	# 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, see <http://www.gnu.org/licenses/>.


	# b4_tocpp(STRING)
	# ----------------
	# Convert STRING into a valid C macro name.
	m4_define([b4_tocpp],
	[m4_toupper(m4_bpatsubst(m4_quote($1), [[^a-zA-Z0-9]+], [_]))])


	# b4_cpp_guard(FILE)
	# ------------------
	# A valid C macro name to use as a CPP header guard for FILE.
	m4_define([b4_cpp_guard],
	[b4_tocpp(m4_defn([b4_prefix])/[$1])])


	# b4_cpp_guard_open(FILE)
	# b4_cpp_guard_close(FILE)
	# ------------------------
	# Open/close CPP inclusion guards for FILE.
	m4_define([b4_cpp_guard_open],
	[#ifndef b4_cpp_guard([$1])
	# define b4_cpp_guard([$1])])

	m4_define([b4_cpp_guard_close],
	[#endif b4_comment([!b4_cpp_guard([$1])])])


	## ---------------- ##
	## Identification. ##
	## ---------------- ##

	# b4_comment_(TEXT, OPEN, CONTINUE, END)
	# -------------------------------------
	# Put TEXT in comment. Avoid trailing spaces: don't indent empty lines.
	# Avoid adding indentation to the first line, as the indentation comes
	# from OPEN. That's why we don't patsubst([$1], [^\(.\)], [ \1]).
	#
	# Prefix all the output lines with PREFIX.
	m4_define([b4_comment_], [$2[]m4_bpatsubst([$1], [
	\(.\)], [
	$3\1])$4])


	# b4_c_comment(TEXT, [PREFIX])
	# ----------------------------
	# Put TEXT in comment. Avoid trailing spaces: don't indent empty lines.
	# Avoid adding indentation to the first line, as the indentation comes
	# from "/*". That's why we don't patsubst([$1], [^\(.\)], [ \1]).
	#
	# Prefix all the output lines with PREFIX.
	m4_define([b4_c_comment],
	[b4_comment_([$1], [$2/* ], [$2 ], [$2 */])])


	# b4_comment(TEXT, [PREFIX])
	# --------------------------
	# By default, C comments.
	m4_define([b4_comment], [b4_c_comment($@)])


	# b4_identification
	# -----------------
	# Depends on individual skeletons to define b4_pure_flag, b4_push_flag, or
	# b4_pull_flag if they use the values of the %define variables api.pure or
	# api.push-pull.
	m4_define([b4_identification],
	[[/* Identify Bison output. */
	#define YYBISON 1

	/* Bison version. */
	#define YYBISON_VERSION "]b4_version["

	/* Skeleton name. */
	#define YYSKELETON_NAME ]b4_skeleton[]m4_ifdef([b4_pure_flag], [[

	/* Pure parsers. */
	#define YYPURE ]b4_pure_flag])[]m4_ifdef([b4_push_flag], [[

	/* Push parsers. */
	#define YYPUSH ]b4_push_flag])[]m4_ifdef([b4_pull_flag], [[

	/* Pull parsers. */
	#define YYPULL ]b4_pull_flag])[
	]])


	## ---------------- ##
	## Default values. ##
	## ---------------- ##

	# b4_api_prefix, b4_api_PREFIX
	# ----------------------------
	# Corresponds to %define api.prefix
	b4_percent_define_default([[api.prefix]], [[yy]])
	m4_define([b4_api_prefix],
	[b4_percent_define_get([[api.prefix]])])
	m4_define([b4_api_PREFIX],
	[m4_toupper(b4_api_prefix)])


	# b4_prefix
	# ---------
	# If the %name-prefix is not given, it is api.prefix.
	m4_define_default([b4_prefix], [b4_api_prefix])

	# If the %union is not named, its name is YYSTYPE.
	m4_define_default([b4_union_name], [b4_api_PREFIX[]STYPE])


	## ------------------------ ##
	## Pure/impure interfaces. ##
	## ------------------------ ##

	# b4_user_args
	# ------------
	m4_define([b4_user_args],
	[m4_ifset([b4_parse_param], [, b4_c_args(b4_parse_param)])])


	# b4_parse_param
	# --------------
	# If defined, b4_parse_param arrives double quoted, but below we prefer
	# it to be single quoted.
	m4_define([b4_parse_param],
	b4_parse_param)


	# b4_parse_param_for(DECL, FORMAL, BODY)
	# ---------------------------------------
	# Iterate over the user parameters, binding the declaration to DECL,
	# the formal name to FORMAL, and evaluating the BODY.
	m4_define([b4_parse_param_for],
	[m4_foreach([$1_$2], m4_defn([b4_parse_param]),
	[m4_pushdef([$1], m4_unquote(m4_car($1_$2)))dnl
	m4_pushdef([$2], m4_shift($1_$2))dnl
	$3[]dnl
	m4_popdef([$2])dnl
	m4_popdef([$1])dnl
	])])

	# b4_parse_param_use([VAL], [LOC])
	# --------------------------------
	# `YYUSE' VAL, LOC if locations are enabled, and all the parse-params.
	m4_define([b4_parse_param_use],
	[m4_ifvaln([$1], [ YYUSE([$1]);])dnl
	b4_locations_if([m4_ifvaln([$2], [ YYUSE ([$2]);])])dnl
	b4_parse_param_for([Decl], [Formal], [ YYUSE (Formal);
	])dnl
	])


	## ------------ ##
	## Data Types. ##
	## ------------ ##

	# b4_int_type(MIN, MAX)
	# ---------------------
	# Return the smallest int type able to handle numbers ranging from
	# MIN to MAX (included).
	m4_define([b4_int_type],
	[m4_if(b4_ints_in($@, [0], [255]), [1], [unsigned char],
	b4_ints_in($@, [-128], [127]), [1], [signed char],

	b4_ints_in($@, [0], [65535]), [1], [unsigned short int],
	b4_ints_in($@, [-32768], [32767]), [1], [short int],

	m4_eval([0 <= $1]), [1], [unsigned int],

	[int])])


	# b4_int_type_for(NAME)
	# ---------------------
	# Return the smallest int type able to handle numbers ranging from
	# `NAME_min' to `NAME_max' (included).
	m4_define([b4_int_type_for],
	[b4_int_type($1_min, $1_max)])


	# b4_table_value_equals(TABLE, VALUE, LITERAL)
	# --------------------------------------------
	# Without inducing a comparison warning from the compiler, check if the
	# literal value LITERAL equals VALUE from table TABLE, which must have
	# TABLE_min and TABLE_max defined. YYID must be defined as an identity
	# function that suppresses warnings about constant conditions.
	m4_define([b4_table_value_equals],
	[m4_if(m4_eval($3 < m4_indir([b4_]$1[_min])
	\|\| m4_indir([b4_]$1[_max]) < $3), [1],
	[[YYID (0)]],
	[[((]$2[) == (]$3[))]])])


	## ---------##
	## Values. ##
	## ---------##


	# b4_null_define
	# --------------
	# Portability issues: define a YY_NULL appropriate for the current
	# language (C, C++98, or C++11).
	m4_define([b4_null_define],
	[# ifndef YY_NULL
	# if defined __cplusplus && 201103L <= __cplusplus
	# define YY_NULL nullptr
	# else
	# define YY_NULL 0
	# endif
	# endif[]dnl
	])


	# b4_null
	# -------
	# Return a null pointer constant.
	m4_define([b4_null], [YY_NULL])

	# b4_integral_parser_table_define(TABLE-NAME, CONTENT, COMMENT)
	# -------------------------------------------------------------
	# Define "yy<TABLE-NAME>" which contents is CONTENT.
	m4_define([b4_integral_parser_table_define],
	[m4_ifvaln([$3], [b4_c_comment([$3], [ ])])dnl
	static const b4_int_type_for([$2]) yy$1[[]] =
	{
	$2
	};dnl
	])


	## ------------------------- ##
	## Assigning token numbers. ##
	## ------------------------- ##

	# b4_token_define(TOKEN-NUM)
	# --------------------------
	# Output the definition of this token as #define.
	m4_define([b4_token_define],
	[b4_token_format([#define %s %s], [$1])])

	# b4_token_defines
	# ----------------
	# Output the definition of the tokens.
	m4_define([b4_token_defines],
	[b4_any_token_visible_if([/* Tokens. */
	m4_join([
	], b4_symbol_map([b4_token_define]))])])


	# b4_token_enum(TOKEN-NUM)
	# ------------------------
	# Output the definition of this token as an enum.
	m4_define([b4_token_enum],
	[b4_token_format([ %s = %s], [$1])])


	# b4_token_enums
	# --------------
	# Output the definition of the tokens (if there are) as enums.
	m4_define([b4_token_enums],
	[b4_any_token_visible_if([[/* Tokens. */
	#ifndef ]b4_api_PREFIX[TOKENTYPE
	# define ]b4_api_PREFIX[TOKENTYPE
	/* Put the tokens into the symbol table, so that GDB and other debuggers
	know about them. */
	enum ]b4_api_prefix[tokentype {
	]m4_join([,
	],
	b4_symbol_map([b4_token_enum]))[
	};
	#endif
	]])])


	# b4_token_enums_defines
	# ----------------------
	# Output the definition of the tokens (if there are any) as enums and,
	# if POSIX Yacc is enabled, as #defines.
	m4_define([b4_token_enums_defines],
	[b4_token_enums[]b4_yacc_if([b4_token_defines])])


	## ----------------- ##
	## Semantic Values. ##
	## ----------------- ##


	# b4_symbol_value(VAL, [TYPE])
	# ----------------------------
	# Given a semantic value VAL ($$, $1 etc.), extract its value of type
	# TYPE if TYPE is given, otherwise just return VAL. The result can be
	# used safetly, it is put in parens to avoid nasty precedence issues.
	# TYPE is not put in braces, provide some if needed.
	m4_define([b4_symbol_value],
	[($1[]m4_ifval([$2], [.$2]))])



	## --------------------------------------------- ##
	## Defining C functions in both K&R and ANSI-C. ##
	## --------------------------------------------- ##


	# b4_modern_c
	# -----------
	# A predicate useful in #if to determine whether C is ancient or modern.
	#
	# If __STDC__ is defined, the compiler is modern. IBM xlc 7.0 when run
	# as 'cc' doesn't define __STDC__ (or __STDC_VERSION__) for pedantic
	# reasons, but it defines __C99__FUNC__ so check that as well.
	# Microsoft C normally doesn't define these macros, but it defines _MSC_VER.
	# Consider a C++ compiler to be modern if it defines __cplusplus.
	#
	m4_define([b4_c_modern],
	[[(defined __STDC__ \|\| defined __C99__FUNC__ \
	\|\| defined __cplusplus \|\| defined _MSC_VER)]])

	# b4_c_function_def(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
	# ----------------------------------------------------------
	# Declare the function NAME.
	m4_define([b4_c_function_def],
	[#if b4_c_modern
	b4_c_ansi_function_def($@)
	#else
	$2
	$1 (b4_c_knr_formal_names(m4_shift2($@)))
	b4_c_knr_formal_decls(m4_shift2($@))
	#endif[]dnl
	])


	# b4_c_ansi_function_def(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
	# ---------------------------------------------------------------
	# Declare the function NAME in ANSI.
	m4_define([b4_c_ansi_function_def],
	[$2
	$1 (b4_c_ansi_formals(m4_shift2($@)))[]dnl
	])


	# b4_c_ansi_formals([DECL1, NAME1], ...)
	# --------------------------------------
	# Output the arguments ANSI-C definition.
	m4_define([b4_c_ansi_formals],
	[m4_if([$#], [0], [void],
	[$#$1], [1], [void],
	[m4_map_sep([b4_c_ansi_formal], [, ], [$@])])])

	m4_define([b4_c_ansi_formal],
	[$1])


	# b4_c_knr_formal_names([DECL1, NAME1], ...)
	# ------------------------------------------
	# Output the argument names.
	m4_define([b4_c_knr_formal_names],
	[m4_map_sep([b4_c_knr_formal_name], [, ], [$@])])

	m4_define([b4_c_knr_formal_name],
	[$2])


	# b4_c_knr_formal_decls([DECL1, NAME1], ...)
	# ------------------------------------------
	# Output the K&R argument declarations.
	m4_define([b4_c_knr_formal_decls],
	[m4_map_sep([b4_c_knr_formal_decl],
	[
	],
	[$@])])

	m4_define([b4_c_knr_formal_decl],
	[ $1;])



	## ------------------------------------------------------------ ##
	## Declaring (prototyping) C functions in both K&R and ANSI-C. ##
	## ------------------------------------------------------------ ##


	# b4_c_function_decl(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
	# -----------------------------------------------------------
	# Declare the function NAME.
	m4_define([b4_c_function_decl],
	[#if b4_c_modern
	b4_c_ansi_function_decl($@)
	#else
	$2 $1 ();
	#endif[]dnl
	])


	# b4_c_ansi_function_decl(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
	# ----------------------------------------------------------------
	# Declare the function NAME.
	m4_define([b4_c_ansi_function_decl],
	[$2 $1 (b4_c_ansi_formals(m4_shift2($@)));[]dnl
	])




	## --------------------- ##
	## Calling C functions. ##
	## --------------------- ##


	# b4_c_function_call(NAME, RETURN-VALUE, [DECL1, NAME1], ...)
	# -----------------------------------------------------------
	# Call the function NAME with arguments NAME1, NAME2 etc.
	m4_define([b4_c_function_call],
	[$1 (b4_c_args(m4_shift2($@)))[]dnl
	])


	# b4_c_args([DECL1, NAME1], ...)
	# ------------------------------
	# Output the arguments NAME1, NAME2...
	m4_define([b4_c_args],
	[m4_map_sep([b4_c_arg], [, ], [$@])])

	m4_define([b4_c_arg],
	[$2])


	## ----------- ##
	## Synclines. ##
	## ----------- ##

	# b4_sync_start(LINE, FILE)
	# -----------------------
	m4_define([b4_sync_start], [[#]line $1 $2])


	## -------------- ##
	## User actions. ##
	## -------------- ##

	# b4_case(LABEL, STATEMENTS)
	# --------------------------
	m4_define([b4_case],
	[ case $1:
	$2
	b4_syncline([@oline@], [@ofile@])
	break;])


	# b4_predicate_case(LABEL, CONDITIONS)
	# ------------------------------------
	m4_define([b4_predicate_case],
	[ case $1:
	if (! ($2)) YYERROR;
	b4_syncline([@oline@], [@ofile@])
	break;])


	# b4_yydestruct_generate(FUNCTION-DECLARATOR)
	# -------------------------------------------
	# Generate the "yydestruct" function, which declaration is issued using
	# FUNCTION-DECLARATOR, which may be "b4_c_ansi_function_def" for ISO C
	# or "b4_c_function_def" for K&R.
	m4_define_default([b4_yydestruct_generate],
	[[/*-----------------------------------------------.
	\| Release the memory associated to this symbol. \|
	`-----------------------------------------------*/

	/ARGSUSED/
	]$1([yydestruct],
	[static void],
	[[const char *yymsg], [yymsg]],
	[[int yytype], [yytype]],
	[[YYSTYPE *yyvaluep], [yyvaluep]][]dnl
	b4_locations_if( [, [[YYLTYPE *yylocationp], [yylocationp]]])[]dnl
	m4_ifset([b4_parse_param], [, b4_parse_param]))[
	{
	]b4_parse_param_use([yyvaluep], [yylocationp])dnl
	[ if (!yymsg)
	yymsg = "Deleting";
	YY_SYMBOL_PRINT (yymsg, yytype, yyvaluep, yylocationp);

	switch (yytype)
	{
	]b4_symbol_foreach([b4_symbol_destructor])dnl
	[ default:
	break;
	}
	}]dnl
	])


	# b4_yy_symbol_print_generate(FUNCTION-DECLARATOR)
	# ------------------------------------------------
	# Generate the "yy_symbol_print" function, which declaration is issued using
	# FUNCTION-DECLARATOR, which may be "b4_c_ansi_function_def" for ISO C
	# or "b4_c_function_def" for K&R.
	m4_define_default([b4_yy_symbol_print_generate],
	[[
	/*--------------------------------.
	\| Print this symbol on YYOUTPUT. \|
	`--------------------------------*/

	/ARGSUSED/
	]$1([yy_symbol_value_print],
	[static void],
	[[FILE *yyoutput], [yyoutput]],
	[[int yytype], [yytype]],
	[[YYSTYPE const * const yyvaluep], [yyvaluep]][]dnl
	b4_locations_if([, [[YYLTYPE const * const yylocationp], [yylocationp]]])[]dnl
	m4_ifset([b4_parse_param], [, b4_parse_param]))[
	{
	FILE *yyo = yyoutput;
	]b4_parse_param_use([yyo], [yylocationp])dnl
	[ if (!yyvaluep)
	return;]
	dnl glr.c does not feature yytoknum.
	m4_if(b4_skeleton, ["yacc.c"],
	[[# ifdef YYPRINT
	if (yytype < YYNTOKENS)
	YYPRINT (yyoutput, yytoknum[yytype], *yyvaluep);
	# endif
	]])dnl
	[ switch (yytype)
	{
	]b4_symbol_foreach([b4_symbol_printer])dnl
	[ default:
	break;
	}
	}


	/*--------------------------------.
	\| Print this symbol on YYOUTPUT. \|
	`--------------------------------*/

	]$1([yy_symbol_print],
	[static void],
	[[FILE *yyoutput], [yyoutput]],
	[[int yytype], [yytype]],
	[[YYSTYPE const * const yyvaluep], [yyvaluep]][]dnl
	b4_locations_if([, [[YYLTYPE const * const yylocationp], [yylocationp]]])[]dnl
	m4_ifset([b4_parse_param], [, b4_parse_param]))[
	{
	if (yytype < YYNTOKENS)
	YYFPRINTF (yyoutput, "token %s (", yytname[yytype]);
	else
	YYFPRINTF (yyoutput, "nterm %s (", yytname[yytype]);

	]b4_locations_if([ YY_LOCATION_PRINT (yyoutput, *yylocationp);
	YYFPRINTF (yyoutput, ": ");
	])dnl
	[ yy_symbol_value_print (yyoutput, yytype, yyvaluep]dnl
	b4_locations_if([, yylocationp])[]b4_user_args[);
	YYFPRINTF (yyoutput, ")");
	}]dnl
	])

	## -------------- ##
	## Declarations. ##
	## -------------- ##

	# b4_declare_yylstype
	# -------------------
	# Declarations that might either go into the header (if --defines) or
	# in the parser body. Declare YYSTYPE/YYLTYPE, and yylval/yylloc.
	m4_define([b4_declare_yylstype],
	[[#if ! defined ]b4_api_PREFIX[STYPE && ! defined ]b4_api_PREFIX[STYPE_IS_DECLARED
	]m4_ifdef([b4_stype],
	[[typedef union ]b4_union_name[
	{
	]b4_user_stype[
	} ]b4_api_PREFIX[STYPE;
	# define ]b4_api_PREFIX[STYPE_IS_TRIVIAL 1]],
	[m4_if(b4_tag_seen_flag, 0,
	[[typedef int ]b4_api_PREFIX[STYPE;
	# define ]b4_api_PREFIX[STYPE_IS_TRIVIAL 1]])])[
	# define ]b4_api_prefix[stype ]b4_api_PREFIX[STYPE /* obsolescent; will be withdrawn */
	# define ]b4_api_PREFIX[STYPE_IS_DECLARED 1
	#endif]b4_locations_if([[

	#if ! defined ]b4_api_PREFIX[LTYPE && ! defined ]b4_api_PREFIX[LTYPE_IS_DECLARED
	typedef struct ]b4_api_PREFIX[LTYPE
	{
	int first_line;
	int first_column;
	int last_line;
	int last_column;
	} ]b4_api_PREFIX[LTYPE;
	# define ]b4_api_prefix[ltype ]b4_api_PREFIX[LTYPE /* obsolescent; will be withdrawn */
	# define ]b4_api_PREFIX[LTYPE_IS_DECLARED 1
	# define ]b4_api_PREFIX[LTYPE_IS_TRIVIAL 1
	#endif]])

	b4_pure_if([], [[extern ]b4_api_PREFIX[STYPE ]b4_prefix[lval;
	]b4_locations_if([[extern ]b4_api_PREFIX[LTYPE ]b4_prefix[lloc;]])])[]dnl
	])

	# b4_YYDEBUG_define
	# ------------------
	m4_define([b4_YYDEBUG_define],
	[[/* Enabling traces. */
	]m4_if(b4_api_prefix, [yy],
	[[#ifndef YYDEBUG
	# define YYDEBUG ]b4_parse_trace_if([1], [0])[
	#endif]],
	[[#ifndef ]b4_api_PREFIX[DEBUG
	# if defined YYDEBUG
	#if YYDEBUG
	# define ]b4_api_PREFIX[DEBUG 1
	# else
	# define ]b4_api_PREFIX[DEBUG 0
	# endif
	# else /* ! defined YYDEBUG */
	# define ]b4_api_PREFIX[DEBUG ]b4_parse_trace_if([1], [0])[
	# endif /* ! defined ]b4_api_PREFIX[DEBUG */
	#endif /* ! defined ]b4_api_PREFIX[DEBUG */]])[]dnl
	])

	# b4_declare_yydebug
	# ------------------
	m4_define([b4_declare_yydebug],
	[b4_YYDEBUG_define[
	#if ]b4_api_PREFIX[DEBUG
	extern int ]b4_prefix[debug;
	#endif][]dnl
	])

	# b4_yylloc_default_define
	# ------------------------
	# Define YYLLOC_DEFAULT.
	m4_define([b4_yylloc_default_define],
	[[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
	If N is 0, then set CURRENT to the empty location which ends
	the previous symbol: RHS[0] (always defined). */

	#ifndef YYLLOC_DEFAULT
	# define YYLLOC_DEFAULT(Current, Rhs, N) \
	do \
	if (YYID (N)) \
	{ \
	(Current).first_line = YYRHSLOC (Rhs, 1).first_line; \
	(Current).first_column = YYRHSLOC (Rhs, 1).first_column; \
	(Current).last_line = YYRHSLOC (Rhs, N).last_line; \
	(Current).last_column = YYRHSLOC (Rhs, N).last_column; \
	} \
	else \
	{ \
	(Current).first_line = (Current).last_line = \
	YYRHSLOC (Rhs, 0).last_line; \
	(Current).first_column = (Current).last_column = \
	YYRHSLOC (Rhs, 0).last_column; \
	} \
	while (YYID (0))
	#endif
	]])