data/c++.m4

   1                                                             -*- Autoconf -*-
   2
   3 # C++ skeleton for Bison
   4
   5 # Copyright (C) 2002-2010 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 b4_percent_define_default([[location_type]], [[location]])
  29 b4_percent_define_default([[filename_type]], [[std::string]])
  30 b4_percent_define_default([[namespace]], m4_defn([b4_prefix]))
  31 b4_percent_define_default([[global_tokens_and_yystype]], [[false]])
  32 b4_percent_define_default([[define_location_comparison]],
  33                           [m4_if(b4_percent_define_get([[filename_type]]),
  34                                  [std::string], [[true]], [[false]])])
  35
  36
  37 ## ----------- ##
  38 ## Namespace.  ##
  39 ## ----------- ##
  40
  41 m4_define([b4_namespace_ref], [b4_percent_define_get([[namespace]])])
  42
  43 # Don't permit an empty b4_namespace_ref.  Any `::parser::foo' appended to it
  44 # would compile as an absolute reference with `parser' in the global namespace.
  45 # b4_namespace_open would open an anonymous namespace and thus establish
  46 # internal linkage.  This would compile.  However, it's cryptic, and internal
  47 # linkage for the parser would be specified in all translation units that
  48 # include the header, which is always generated.  If we ever need to permit
  49 # internal linkage somehow, surely we can find a cleaner approach.
  50 m4_if(m4_bregexp(b4_namespace_ref, [^[   ]*$]), [-1], [],
  51 [b4_complain_at(b4_percent_define_get_loc([[namespace]]),
  52                 [[namespace reference is empty]])])
  53
  54 # Instead of assuming the C++ compiler will do it, Bison should reject any
  55 # invalid b4_namepsace_ref that would be converted to a valid
  56 # b4_namespace_open.  The problem is that Bison doesn't always output
  57 # b4_namespace_ref to uncommented code but should reserve the ability to do so
  58 # in future releases without risking breaking any existing user grammars.
  59 # Specifically, don't allow empty names as b4_namespace_open would just convert
  60 # those into anonymous namespaces, and that might tempt some users.
  61 m4_if(m4_bregexp(b4_namespace_ref, [::[  ]*::]), [-1], [],
  62 [b4_complain_at(b4_percent_define_get_loc([[namespace]]),
  63                 [[namespace reference has consecutive "::"]])])
  64 m4_if(m4_bregexp(b4_namespace_ref, [::[  ]*$]), [-1], [],
  65 [b4_complain_at(b4_percent_define_get_loc([[namespace]]),
  66                 [[namespace reference has a trailing "::"]])])
  67
  68 m4_define([b4_namespace_open],
  69 [b4_user_code([b4_percent_define_get_syncline([[namespace]])
  70 [namespace ]m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref),
  71                                                 [^\(.\)[         ]*::], [\1])),
  72                          [::], [ { namespace ])[ {]])])
  73
  74 m4_define([b4_namespace_close],
  75 [b4_user_code([b4_percent_define_get_syncline([[namespace]])
  76 m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref[ ]),
  77                                     [^\(.\)[     ]*\(::\)?\([^][:]\|:[^:]\)*],
  78                                     [\1])),
  79              [::\([^][:]\|:[^:]\)*], [} ])[} // ]b4_namespace_ref])])
  80
  81
  82 # b4_token_enums(LIST-OF-PAIRS-TOKEN-NAME-TOKEN-NUMBER)
  83 # -----------------------------------------------------
  84 # Output the definition of the tokens as enums.
  85 m4_define([b4_token_enums],
  86 [/* Tokens.  */
  87    enum yytokentype {
  88 m4_map_sep([     b4_token_enum], [,
  89 ],
  90            [$@])
  91    };
  92 ])
  93
  94
  95 ## ----------------- ##
  96 ## Semantic Values.  ##
  97 ## ----------------- ##
  98
  99
 100 # b4_lhs_value([TYPE])
 101 # --------------------
 102 # Expansion of $<TYPE>$.
 103 m4_define([b4_lhs_value],
 104 [(yyval[]m4_ifval([$1], [.$1]))])
 105
 106
 107 # b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
 108 # --------------------------------------
 109 # Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
 110 # symbols on RHS.
 111 m4_define([b4_rhs_value],
 112 [(yysemantic_stack_@{($1) - ($2)@}m4_ifval([$3], [.$3]))])
 113
 114 # b4_lhs_location()
 115 # -----------------
 116 # Expansion of @$.
 117 m4_define([b4_lhs_location],
 118 [(yyloc)])
 119
 120
 121 # b4_rhs_location(RULE-LENGTH, NUM)
 122 # ---------------------------------
 123 # Expansion of @NUM, where the current rule has RULE-LENGTH symbols
 124 # on RHS.
 125 m4_define([b4_rhs_location],
 126 [(yylocation_stack_@{($1) - ($2)@})])
 127
 128
 129 # b4_parse_param_decl
 130 # -------------------
 131 # Extra formal arguments of the constructor.
 132 # Change the parameter names from "foo" into "foo_yyarg", so that
 133 # there is no collision bw the user chosen attribute name, and the
 134 # argument name in the constructor.
 135 m4_define([b4_parse_param_decl],
 136 [m4_ifset([b4_parse_param],
 137           [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
 138
 139 m4_define([b4_parse_param_decl_1],
 140 [$1_yyarg])
 141
 142
 143
 144 # b4_parse_param_cons
 145 # -------------------
 146 # Extra initialisations of the constructor.
 147 m4_define([b4_parse_param_cons],
 148           [m4_ifset([b4_parse_param],
 149                     [
 150       b4_cc_constructor_calls(b4_parse_param)])])
 151 m4_define([b4_cc_constructor_calls],
 152           [m4_map_sep([b4_cc_constructor_call], [,
 153       ], [$@])])
 154 m4_define([b4_cc_constructor_call],
 155           [$2 ($2_yyarg)])
 156
 157 # b4_parse_param_vars
 158 # -------------------
 159 # Extra instance variables.
 160 m4_define([b4_parse_param_vars],
 161           [m4_ifset([b4_parse_param],
 162                     [
 163     /* User arguments.  */
 164 b4_cc_var_decls(b4_parse_param)])])
 165 m4_define([b4_cc_var_decls],
 166           [m4_map_sep([b4_cc_var_decl], [
 167 ], [$@])])
 168 m4_define([b4_cc_var_decl],
 169           [    $1;])