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1 -*- C -*-
2
3 # C++ GLR skeleton for Bison
4
5 # Copyright (C) 2002-2011 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
21 # This skeleton produces a C++ class that encapsulates a C glr parser.
22 # This is in order to reduce the maintenance burden. The glr.c
23 # skeleton is clean and pure enough so that there are no real
24 # problems. The C++ interface is the same as that of lalr1.cc. In
25 # fact, glr.c can replace yacc.c without the user noticing any
26 # difference, and similarly for glr.cc replacing lalr1.cc.
27 #
28 # The passing of parse-params
29 #
30 # The additional arguments are stored as members of the parser
31 # object, yyparser. The C routines need to carry yyparser
32 # throughout the C parser; that easy: just let yyparser become an
33 # additional parse-param. But because the C++ skeleton needs to
34 # know the "real" original parse-param, we save them
35 # (b4_parse_param_orig). Note that b4_parse_param is overquoted
36 # (and c.m4 strips one level of quotes). This is a PITA, and
37 # explains why there are so many levels of quotes.
38 #
39 # The locations
40 #
41 # We use location.cc just like lalr1.cc, but because glr.c stores
42 # the locations in a (C++) union, the position and location classes
43 # must not have a constructor. Therefore, contrary to lalr1.cc, we
44 # must not define "b4_location_constructors". As a consequence the
45 # user must initialize the first positions (in particular the
46 # filename member).
47
48 # We require a pure interface using locations.
49 m4_define([b4_locations_flag], [1])
50 m4_define([b4_pure_flag], [1])
51
52 # The header is mandatory.
53 b4_defines_if([],
54 [b4_fatal([b4_skeleton[: using %%defines is mandatory]])])
55
56 m4_include(b4_pkgdatadir/[c++.m4])
57 b4_percent_define_ifdef([[location_type]], [],
58 [m4_include(b4_pkgdatadir/[location.cc])])
59
60 m4_define([b4_parser_class_name],
61 [b4_percent_define_get([[parser_class_name]])])
62
63 # Save the parse parameters.
64 m4_define([b4_parse_param_orig], m4_defn([b4_parse_param]))
65
66
67 # b4_yy_symbol_print_generate
68 # ---------------------------
69 # Bypass the default implementation to generate the "yy_symbol_print"
70 # and "yy_symbol_value_print" functions.
71 m4_define([b4_yy_symbol_print_generate],
72 [[
73 /*--------------------.
74 | Print this symbol. |
75 `--------------------*/
76
77 ]b4_c_ansi_function_def([yy_symbol_print],
78 [static void],
79 [[FILE *], []],
80 [[int yytype], [yytype]],
81 [[const b4_namespace_ref::b4_parser_class_name::semantic_type *yyvaluep],
82 [yyvaluep]],
83 [[const b4_namespace_ref::b4_parser_class_name::location_type *yylocationp],
84 [yylocationp]],
85 b4_parse_param)[
86 {
87 ]b4_parse_param_use[]dnl
88 [ yyparser.yy_symbol_print_ (yytype, yyvaluep]b4_locations_if([, yylocationp])[);
89 }
90 ]])
91
92
93 # Declare yyerror.
94 m4_append([b4_post_prologue],
95 [b4_syncline([@oline@], [@ofile@])
96
97 b4_c_ansi_function_decl([yyerror],
98 [static void],
99 [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
100 b4_parse_param,
101 [[const char* msg], [msg]])])
102
103
104 # Define yyerror.
105 m4_append([b4_epilogue],
106 [b4_syncline([@oline@], [@ofile@])[
107 /*------------------.
108 | Report an error. |
109 `------------------*/
110
111 ]b4_c_ansi_function_def([yyerror],
112 [static void],
113 [[b4_namespace_ref::b4_parser_class_name::location_type *yylocationp], [yylocationp]],
114 b4_parse_param,
115 [[const char* msg], [msg]])[
116 {
117 ]b4_parse_param_use[]dnl
118 [ yyparser.error (*yylocationp, msg);
119 }
120
121
122 ]b4_namespace_open[
123 ]dnl In this section, the parse param are the original parse_params.
124 m4_pushdef([b4_parse_param], m4_defn([b4_parse_param_orig]))dnl
125 [ /// Build a parser object.
126 ]b4_parser_class_name::b4_parser_class_name[ (]b4_parse_param_decl[)]m4_ifset([b4_parse_param], [
127 :])[
128 #if YYDEBUG
129 ]m4_ifset([b4_parse_param], [ ], [ :])[yydebug_ (false),
130 yycdebug_ (&std::cerr)]m4_ifset([b4_parse_param], [,])[
131 #endif]b4_parse_param_cons[
132 {
133 }
134
135 ]b4_parser_class_name::~b4_parser_class_name[ ()
136 {
137 }
138
139 int
140 ]b4_parser_class_name[::parse ()
141 {
142 return ::yyparse (*this]b4_user_args[);
143 }
144
145 #if YYDEBUG
146 /*--------------------.
147 | Print this symbol. |
148 `--------------------*/
149
150 inline void
151 ]b4_parser_class_name[::yy_symbol_value_print_ (int yytype,
152 const semantic_type* yyvaluep, const location_type* yylocationp)
153 {
154 /* Pacify ``unused variable'' warnings. */
155 YYUSE (yyvaluep);
156 YYUSE (yylocationp);
157 switch (yytype)
158 {
159 ]m4_map([b4_symbol_actions], m4_defn([b4_symbol_printers]))dnl
160 [ default:
161 break;
162 }
163 }
164
165
166 void
167 ]b4_parser_class_name[::yy_symbol_print_ (int yytype,
168 const semantic_type* yyvaluep, const location_type* yylocationp)
169 {
170 *yycdebug_ << (yytype < YYNTOKENS ? "token" : "nterm")
171 << ' ' << yytname[yytype] << " ("
172 << *yylocationp << ": ";
173 yy_symbol_value_print_ (yytype, yyvaluep, yylocationp);
174 *yycdebug_ << ')';
175 }
176
177 std::ostream&
178 ]b4_parser_class_name[::debug_stream () const
179 {
180 return *yycdebug_;
181 }
182
183 void
184 ]b4_parser_class_name[::set_debug_stream (std::ostream& o)
185 {
186 yycdebug_ = &o;
187 }
188
189
190 ]b4_parser_class_name[::debug_level_type
191 ]b4_parser_class_name[::debug_level () const
192 {
193 return yydebug_;
194 }
195
196 void
197 ]b4_parser_class_name[::set_debug_level (debug_level_type l)
198 {
199 yydebug_ = l;
200 }
201
202 #endif
203 ]m4_popdef([b4_parse_param])dnl
204 b4_namespace_close[
205
206 ]])
207
208
209 # Let glr.c believe that the user arguments include the parser itself.
210 m4_ifset([b4_parse_param],
211 [m4_pushdef([b4_parse_param],
212 m4_dquote([[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]],]
213 m4_defn([b4_parse_param])))],
214 [m4_pushdef([b4_parse_param],
215 [[[[b4_namespace_ref::b4_parser_class_name& yyparser], [[yyparser]]]]])
216 ])
217 m4_include(b4_pkgdatadir/[glr.c])
218 m4_popdef([b4_parse_param])
219
220 m4_divert_push(0)
221 @output(b4_spec_defines_file@)@
222 b4_copyright([Skeleton interface for Bison GLR parsers in C++],
223 [2002-2006, 2009-2011])[
224
225 /* C++ GLR parser skeleton written by Akim Demaille. */
226
227 #ifndef PARSER_HEADER_H
228 # define PARSER_HEADER_H
229
230 ]b4_percent_code_get([[requires]])[
231
232 #include <string>
233 #include <iostream>
234 ]b4_percent_define_ifdef([[location_type]], [],
235 [[#include "location.hh"]])[
236
237 /* Using locations. */
238 #define YYLSP_NEEDED ]b4_locations_flag[
239
240 /* Enabling traces. */
241 #ifndef YYDEBUG
242 # define YYDEBUG ]b4_debug_flag[
243 #endif
244
245 /* YYLLOC_DEFAULT -- Set CURRENT to span from RHS[1] to RHS[N].
246 If N is 0, then set CURRENT to the empty location which ends
247 the previous symbol: RHS[0] (always defined). */
248
249 #ifndef YYLLOC_DEFAULT
250 # define YYLLOC_DEFAULT(Current, Rhs, N) \
251 do \
252 if (N) \
253 { \
254 (Current).begin = YYRHSLOC (Rhs, 1).begin; \
255 (Current).end = YYRHSLOC (Rhs, N).end; \
256 } \
257 else \
258 { \
259 (Current).begin = (Current).end = YYRHSLOC (Rhs, 0).end; \
260 } \
261 while (/*CONSTCOND*/ 0)
262 #endif
263
264 ]b4_namespace_open[
265 /// A Bison parser.
266 class ]b4_parser_class_name[
267 {
268 public:
269 /// Symbol semantic values.
270 #ifndef YYSTYPE
271 ]m4_ifdef([b4_stype],
272 [ union semantic_type
273 {
274 b4_user_stype
275 };],
276 [m4_if(b4_tag_seen_flag, 0,
277 [[ typedef int semantic_type;]],
278 [[ typedef YYSTYPE semantic_type;]])])[
279 #else
280 typedef YYSTYPE semantic_type;
281 #endif
282 /// Symbol locations.
283 typedef ]b4_percent_define_get([[location_type]],
284 [[location]])[ location_type;
285 /// Tokens.
286 struct token
287 {
288 ]b4_token_enums(b4_tokens)[
289 };
290 /// Token type.
291 typedef token::yytokentype token_type;
292
293 /// Build a parser object.
294 ]b4_parser_class_name[ (]b4_parse_param_decl[);
295 virtual ~]b4_parser_class_name[ ();
296
297 /// Parse.
298 /// \returns 0 iff parsing succeeded.
299 virtual int parse ();
300
301 /// The current debugging stream.
302 std::ostream& debug_stream () const;
303 /// Set the current debugging stream.
304 void set_debug_stream (std::ostream &);
305
306 /// Type for debugging levels.
307 typedef int debug_level_type;
308 /// The current debugging level.
309 debug_level_type debug_level () const;
310 /// Set the current debugging level.
311 void set_debug_level (debug_level_type l);
312
313 private:
314
315 public:
316 /// Report a syntax error.
317 /// \param loc where the syntax error is found.
318 /// \param msg a description of the syntax error.
319 virtual void error (const location_type& loc, const std::string& msg);
320 private:
321
322 #if YYDEBUG
323 public:
324 /// \brief Report a symbol value on the debug stream.
325 /// \param yytype The token type.
326 /// \param yyvaluep Its semantic value.
327 /// \param yylocationp Its location.
328 virtual void yy_symbol_value_print_ (int yytype,
329 const semantic_type* yyvaluep,
330 const location_type* yylocationp);
331 /// \brief Report a symbol on the debug stream.
332 /// \param yytype The token type.
333 /// \param yyvaluep Its semantic value.
334 /// \param yylocationp Its location.
335 virtual void yy_symbol_print_ (int yytype,
336 const semantic_type* yyvaluep,
337 const location_type* yylocationp);
338 private:
339 /* Debugging. */
340 int yydebug_;
341 std::ostream* yycdebug_;
342 #endif
343
344
345 /// \brief Reclaim the memory associated to a symbol.
346 /// \param yymsg Why this token is reclaimed.
347 /// \param yytype The symbol type.
348 /// \param yyvaluep Its semantic value.
349 /// \param yylocationp Its location.
350 inline void yydestruct_ (const char* yymsg,
351 int yytype,
352 semantic_type* yyvaluep,
353 location_type* yylocationp);
354
355 ]b4_parse_param_vars[
356 };
357
358 ]dnl Redirections for glr.c.
359 b4_percent_define_flag_if([[global_tokens_and_yystype]],
360 [b4_token_defines(b4_tokens)])
361 [
362 #ifndef YYSTYPE
363 # define YYSTYPE ]b4_namespace_ref[::]b4_parser_class_name[::semantic_type
364 #endif
365 #ifndef YYLTYPE
366 # define YYLTYPE ]b4_namespace_ref[::]b4_parser_class_name[::location_type
367 #endif
368
369 ]b4_namespace_close[
370
371 ]b4_percent_code_get([[provides]])[]dnl
372
373 [#endif /* ! defined PARSER_HEADER_H */]
374 m4_divert_pop(0)