data/c++.m4

   1                                                             -*- Autoconf -*-
   2
   3 # C++ skeleton for Bison
   4
   5 # Copyright (C) 2002-2012 Free Software Foundation, Inc.
   6
   7 # This program is free software: you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation, either version 3 of the License, or
  10 # (at your option) any later version.
  11 #
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16 #
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19
  20 m4_include(b4_pkgdatadir/[c.m4])
  21
  22 ## ---------------- ##
  23 ## Default values.  ##
  24 ## ---------------- ##
  25
  26 # Default parser class name.
  27 b4_percent_define_default([[parser_class_name]], [[parser]])
  28
  29 # Don't do that so that we remember whether we're using a user
  30 # request, or the default value.
  31 #
  32 # b4_percent_define_default([[location_type]], [[location]])
  33
  34 b4_percent_define_default([[filename_type]], [[std::string]])
  35 b4_percent_define_default([[namespace]], m4_defn([b4_prefix]))
  36 b4_percent_define_default([[global_tokens_and_yystype]], [[false]])
  37 b4_percent_define_default([[define_location_comparison]],
  38                           [m4_if(b4_percent_define_get([[filename_type]]),
  39                                  [std::string], [[true]], [[false]])])
  40
  41
  42 ## ----------- ##
  43 ## Namespace.  ##
  44 ## ----------- ##
  45
  46 m4_define([b4_namespace_ref], [b4_percent_define_get([[namespace]])])
  47
  48 # Don't permit an empty b4_namespace_ref.  Any `::parser::foo' appended to it
  49 # would compile as an absolute reference with `parser' in the global namespace.
  50 # b4_namespace_open would open an anonymous namespace and thus establish
  51 # internal linkage.  This would compile.  However, it's cryptic, and internal
  52 # linkage for the parser would be specified in all translation units that
  53 # include the header, which is always generated.  If we ever need to permit
  54 # internal linkage somehow, surely we can find a cleaner approach.
  55 m4_if(m4_bregexp(b4_namespace_ref, [^[   ]*$]), [-1], [],
  56 [b4_complain_at(b4_percent_define_get_loc([[namespace]]),
  57                 [[namespace reference is empty]])])
  58
  59 # Instead of assuming the C++ compiler will do it, Bison should reject any
  60 # invalid b4_namepsace_ref that would be converted to a valid
  61 # b4_namespace_open.  The problem is that Bison doesn't always output
  62 # b4_namespace_ref to uncommented code but should reserve the ability to do so
  63 # in future releases without risking breaking any existing user grammars.
  64 # Specifically, don't allow empty names as b4_namespace_open would just convert
  65 # those into anonymous namespaces, and that might tempt some users.
  66 m4_if(m4_bregexp(b4_namespace_ref, [::[  ]*::]), [-1], [],
  67 [b4_complain_at(b4_percent_define_get_loc([[namespace]]),
  68                 [[namespace reference has consecutive "::"]])])
  69 m4_if(m4_bregexp(b4_namespace_ref, [::[  ]*$]), [-1], [],
  70 [b4_complain_at(b4_percent_define_get_loc([[namespace]]),
  71                 [[namespace reference has a trailing "::"]])])
  72
  73 m4_define([b4_namespace_open],
  74 [b4_user_code([b4_percent_define_get_syncline([[namespace]])
  75 [namespace ]m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref),
  76                                                 [^\(.\)[         ]*::], [\1])),
  77                          [::], [ { namespace ])[ {]])])
  78
  79 m4_define([b4_namespace_close],
  80 [b4_user_code([b4_percent_define_get_syncline([[namespace]])
  81 m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref[ ]),
  82                                     [^\(.\)[     ]*\(::\)?\([^][:]\|:[^:]\)*],
  83                                     [\1])),
  84              [::\([^][:]\|:[^:]\)*], [} ])[} // ]b4_namespace_ref])])
  85
  86
  87 # b4_token_enums(LIST-OF-PAIRS-TOKEN-NAME-TOKEN-NUMBER)
  88 # -----------------------------------------------------
  89 # Output the definition of the tokens as enums.
  90 m4_define([b4_token_enums],
  91 [/* Tokens.  */
  92    enum yytokentype {
  93 m4_map_sep([     b4_token_enum], [,
  94 ],
  95            [$@])
  96    };
  97 ])
  98
  99
 100 ## ----------------- ##
 101 ## Semantic Values.  ##
 102 ## ----------------- ##
 103
 104
 105 # b4_lhs_value([TYPE])
 106 # --------------------
 107 # Expansion of $<TYPE>$.
 108 m4_define([b4_lhs_value],
 109 [(yyval[]m4_ifval([$1], [.$1]))])
 110
 111
 112 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
 113 # --------------------------------------
 114 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
 115 # symbols on RHS.
 116 m4_define([b4_rhs_value],
 117 [(yysemantic_stack_@{($1) - ($2)@}m4_ifval([$3], [.$3]))])
 118
 119 # b4_lhs_location()
 120 # -----------------
 121 # Expansion of @$.
 122 m4_define([b4_lhs_location],
 123 [(yyloc)])
 124
 125
 126 # b4_rhs_location(RULE-LENGTH, NUM)
 127 # ---------------------------------
 128 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
 129 # on RHS.
 130 m4_define([b4_rhs_location],
 131 [(yylocation_stack_@{($1) - ($2)@})])
 132
 133
 134 # b4_parse_param_decl
 135 # -------------------
 136 # Extra formal arguments of the constructor.
 137 # Change the parameter names from "foo" into "foo_yyarg", so that
 138 # there is no collision bw the user chosen attribute name, and the
 139 # argument name in the constructor.
 140 m4_define([b4_parse_param_decl],
 141 [m4_ifset([b4_parse_param],
 142           [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
 143
 144 m4_define([b4_parse_param_decl_1],
 145 [$1_yyarg])
 146
 147
 148
 149 # b4_parse_param_cons
 150 # -------------------
 151 # Extra initialisations of the constructor.
 152 m4_define([b4_parse_param_cons],
 153           [m4_ifset([b4_parse_param],
 154                     [
 155       b4_cc_constructor_calls(b4_parse_param)])])
 156 m4_define([b4_cc_constructor_calls],
 157           [m4_map_sep([b4_cc_constructor_call], [,
 158       ], [$@])])
 159 m4_define([b4_cc_constructor_call],
 160           [$2 ($2_yyarg)])
 161
 162 # b4_parse_param_vars
 163 # -------------------
 164 # Extra instance variables.
 165 m4_define([b4_parse_param_vars],
 166           [m4_ifset([b4_parse_param],
 167                     [
 168     /* User arguments.  */
 169 b4_cc_var_decls(b4_parse_param)])])
 170 m4_define([b4_cc_var_decls],
 171           [m4_map_sep([b4_cc_var_decl], [
 172 ], [$@])])
 173 m4_define([b4_cc_var_decl],
 174           [    $1;])