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
20m4_include(b4_pkgdatadir/[c.m4])
21
22## ---------------- ##
23## Default values.  ##
24## ---------------- ##
25
26# Default parser class name.
27b4_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([[api.location.type]], [[location]])
33
34b4_percent_define_default([[filename_type]], [[std::string]])
35b4_percent_define_default([[namespace]], m4_defn([b4_prefix]))
36b4_percent_define_default([[global_tokens_and_yystype]], [[false]])
37b4_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
46m4_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.
55m4_if(m4_bregexp(b4_namespace_ref, [^[	 ]*$]), [-1], [],
56[b4_complain_at(b4_percent_define_get_loc([[namespace]]),
57                [[namespace reference is empty]])])
58
59# Instead of assuming the C++ compiler will do it, Bison should reject any
60# invalid b4_namepsace_ref that would be converted to a valid
61# b4_namespace_open.  The problem is that Bison doesn't always output
62# b4_namespace_ref to uncommented code but should reserve the ability to do so
63# in future releases without risking breaking any existing user grammars.
64# Specifically, don't allow empty names as b4_namespace_open would just convert
65# those into anonymous namespaces, and that might tempt some users.
66m4_if(m4_bregexp(b4_namespace_ref, [::[	 ]*::]), [-1], [],
67[b4_complain_at(b4_percent_define_get_loc([[namespace]]),
68                [[namespace reference has consecutive "::"]])])
69m4_if(m4_bregexp(b4_namespace_ref, [::[	 ]*$]), [-1], [],
70[b4_complain_at(b4_percent_define_get_loc([[namespace]]),
71                [[namespace reference has a trailing "::"]])])
72
73m4_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
79m4_define([b4_namespace_close],
80[b4_user_code([b4_percent_define_get_syncline([[namespace]])
81m4_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.
90m4_define([b4_token_enums],
91[/* Tokens.  */
92   enum yytokentype {
93m4_map_sep([     b4_token_enum], [,
94],
95           [$@])
96   };
97])
98
99
100
101
102## ----------------- ##
103## Semantic Values.  ##
104## ----------------- ##
105
106
107# b4_lhs_value([TYPE])
108# --------------------
109# Expansion of $<TYPE>$.
110m4_define([b4_lhs_value],
111[(yyval[]m4_ifval([$1], [.$1]))])
112
113
114# b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
115# --------------------------------------
116# Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
117# symbols on RHS.
118m4_define([b4_rhs_value],
119[(yysemantic_stack_@{($1) - ($2)@}m4_ifval([$3], [.$3]))])
120
121# b4_lhs_location()
122# -----------------
123# Expansion of @$.
124m4_define([b4_lhs_location],
125[(yyloc)])
126
127
128# b4_rhs_location(RULE-LENGTH, NUM)
129# ---------------------------------
130# Expansion of @NUM, where the current rule has RULE-LENGTH symbols
131# on RHS.
132m4_define([b4_rhs_location],
133[(yylocation_stack_@{($1) - ($2)@})])
134
135
136# b4_parse_param_decl
137# -------------------
138# Extra formal arguments of the constructor.
139# Change the parameter names from "foo" into "foo_yyarg", so that
140# there is no collision bw the user chosen attribute name, and the
141# argument name in the constructor.
142m4_define([b4_parse_param_decl],
143[m4_ifset([b4_parse_param],
144          [m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
145
146m4_define([b4_parse_param_decl_1],
147[$1_yyarg])
148
149
150
151# b4_parse_param_cons
152# -------------------
153# Extra initialisations of the constructor.
154m4_define([b4_parse_param_cons],
155          [m4_ifset([b4_parse_param],
156		    [
157      b4_cc_constructor_calls(b4_parse_param)])])
158m4_define([b4_cc_constructor_calls],
159	  [m4_map_sep([b4_cc_constructor_call], [,
160      ], [$@])])
161m4_define([b4_cc_constructor_call],
162	  [$2 ($2_yyarg)])
163
164# b4_parse_param_vars
165# -------------------
166# Extra instance variables.
167m4_define([b4_parse_param_vars],
168          [m4_ifset([b4_parse_param],
169		    [
170    /* User arguments.  */
171b4_cc_var_decls(b4_parse_param)])])
172m4_define([b4_cc_var_decls],
173	  [m4_map_sep([b4_cc_var_decl], [
174], [$@])])
175m4_define([b4_cc_var_decl],
176	  [    $1;])
177
178
179## ---------##
180## Values.  ##
181## ---------##
182
183# b4_yylloc_default_define
184# ------------------------
185# Define YYLLOC_DEFAULT.
186m4_define([b4_yylloc_default_define],
187[[/* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
188   If N is 0, then set CURRENT to the empty location which ends
189   the previous symbol: RHS[0] (always defined).  */
190
191# ifndef YYLLOC_DEFAULT
192#  define YYLLOC_DEFAULT(Current, Rhs, N)                               \
193    do                                                                  \
194      if (N)                                                            \
195        {                                                               \
196          (Current).begin  = YYRHSLOC (Rhs, 1).begin;                   \
197          (Current).end    = YYRHSLOC (Rhs, N).end;                     \
198        }                                                               \
199      else                                                              \
200        {                                                               \
201          (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end;      \
202        }                                                               \
203    while (/*CONSTCOND*/ false)
204# endif
205]])
206