| 1 | Bison News |
| 2 | ---------- |
| 3 | |
| 4 | Changes in version 2.0, 2004-12-25: |
| 5 | |
| 6 | * Possibly-incompatible changes |
| 7 | |
| 8 | - Bison-generated parsers no longer default to using the alloca function |
| 9 | (when available) to extend the parser stack, due to widespread |
| 10 | problems in unchecked stack-overflow detection. You can "#define |
| 11 | YYSTACK_USE_ALLOCA 1" to require the use of alloca, but please read |
| 12 | the manual to determine safe values for YYMAXDEPTH in that case. |
| 13 | |
| 14 | - Error token location. |
| 15 | During error recovery, the location of the syntax error is updated |
| 16 | to cover the whole sequence covered by the error token: it includes |
| 17 | the shifted symbols thrown away during the first part of the error |
| 18 | recovery, and the lookahead rejected during the second part. |
| 19 | |
| 20 | - Semicolon changes: |
| 21 | . Stray semicolons are no longer allowed at the start of a grammar. |
| 22 | . Semicolons are now required after in-grammar declarations. |
| 23 | |
| 24 | - Unescaped newlines are no longer allowed in character constants or |
| 25 | string literals. They were never portable, and GCC 3.4.0 has |
| 26 | dropped support for them. Better diagnostics are now generated if |
| 27 | forget a closing quote. |
| 28 | |
| 29 | - NUL bytes are no longer allowed in Bison string literals, unfortunately. |
| 30 | |
| 31 | * New features |
| 32 | |
| 33 | - GLR grammars now support locations. |
| 34 | |
| 35 | - New directive: %initial-action. |
| 36 | This directive allows the user to run arbitrary code (including |
| 37 | initializing @$) from yyparse before parsing starts. |
| 38 | |
| 39 | - A new directive "%expect-rr N" specifies the expected number of |
| 40 | reduce/reduce conflicts in GLR parsers. |
| 41 | |
| 42 | - %token numbers can now be hexadecimal integers, e.g., `%token FOO 0x12d'. |
| 43 | This is a GNU extension. |
| 44 | |
| 45 | - The option `--report=lookahead' was changed to `--report=look-ahead'. |
| 46 | The old spelling still works, but is not documented and will be |
| 47 | removed. |
| 48 | |
| 49 | - Experimental %destructor support has been added to lalr1.cc. |
| 50 | |
| 51 | - New configure option --disable-yacc, to disable installation of the |
| 52 | yacc command and -ly library introduced in 1.875 for POSIX conformance. |
| 53 | |
| 54 | * Bug fixes |
| 55 | |
| 56 | - For now, %expect-count violations are now just warnings, not errors. |
| 57 | This is for compatibility with Bison 1.75 and earlier (when there are |
| 58 | reduce/reduce conflicts) and with Bison 1.30 and earlier (when there |
| 59 | are too many or too few shift/reduce conflicts). However, in future |
| 60 | versions of Bison we plan to improve the %expect machinery so that |
| 61 | these violations will become errors again. |
| 62 | |
| 63 | - Within Bison itself, numbers (e.g., goto numbers) are no longer |
| 64 | arbitrarily limited to 16-bit counts. |
| 65 | |
| 66 | - Semicolons are now allowed before "|" in grammar rules, as POSIX requires. |
| 67 | \f |
| 68 | Changes in version 1.875, 2003-01-01: |
| 69 | |
| 70 | * The documentation license has been upgraded to version 1.2 |
| 71 | of the GNU Free Documentation License. |
| 72 | |
| 73 | * syntax error processing |
| 74 | |
| 75 | - In Yacc-style parsers YYLLOC_DEFAULT is now used to compute error |
| 76 | locations too. This fixes bugs in error-location computation. |
| 77 | |
| 78 | - %destructor |
| 79 | It is now possible to reclaim the memory associated to symbols |
| 80 | discarded during error recovery. This feature is still experimental. |
| 81 | |
| 82 | - %error-verbose |
| 83 | This new directive is preferred over YYERROR_VERBOSE. |
| 84 | |
| 85 | - #defining yyerror to steal internal variables is discouraged. |
| 86 | It is not guaranteed to work forever. |
| 87 | |
| 88 | * POSIX conformance |
| 89 | |
| 90 | - Semicolons are once again optional at the end of grammar rules. |
| 91 | This reverts to the behavior of Bison 1.33 and earlier, and improves |
| 92 | compatibility with Yacc. |
| 93 | |
| 94 | - `parse error' -> `syntax error' |
| 95 | Bison now uniformly uses the term `syntax error'; formerly, the code |
| 96 | and manual sometimes used the term `parse error' instead. POSIX |
| 97 | requires `syntax error' in diagnostics, and it was thought better to |
| 98 | be consistent. |
| 99 | |
| 100 | - The documentation now emphasizes that yylex and yyerror must be |
| 101 | declared before use. C99 requires this. |
| 102 | |
| 103 | - Bison now parses C99 lexical constructs like UCNs and |
| 104 | backslash-newline within C escape sequences, as POSIX 1003.1-2001 requires. |
| 105 | |
| 106 | - File names are properly escaped in C output. E.g., foo\bar.y is |
| 107 | output as "foo\\bar.y". |
| 108 | |
| 109 | - Yacc command and library now available |
| 110 | The Bison distribution now installs a `yacc' command, as POSIX requires. |
| 111 | Also, Bison now installs a small library liby.a containing |
| 112 | implementations of Yacc-compatible yyerror and main functions. |
| 113 | This library is normally not useful, but POSIX requires it. |
| 114 | |
| 115 | - Type clashes now generate warnings, not errors. |
| 116 | |
| 117 | - If the user does not define YYSTYPE as a macro, Bison now declares it |
| 118 | using typedef instead of defining it as a macro. |
| 119 | For consistency, YYLTYPE is also declared instead of defined. |
| 120 | |
| 121 | * Other compatibility issues |
| 122 | |
| 123 | - %union directives can now have a tag before the `{', e.g., the |
| 124 | directive `%union foo {...}' now generates the C code |
| 125 | `typedef union foo { ... } YYSTYPE;'; this is for Yacc compatibility. |
| 126 | The default union tag is `YYSTYPE', for compatibility with Solaris 9 Yacc. |
| 127 | For consistency, YYLTYPE's struct tag is now `YYLTYPE' not `yyltype'. |
| 128 | This is for compatibility with both Yacc and Bison 1.35. |
| 129 | |
| 130 | - `;' is output before the terminating `}' of an action, for |
| 131 | compatibility with Bison 1.35. |
| 132 | |
| 133 | - Bison now uses a Yacc-style format for conflict reports, e.g., |
| 134 | `conflicts: 2 shift/reduce, 1 reduce/reduce'. |
| 135 | |
| 136 | - `yystype' and `yyltype' are now obsolescent macros instead of being |
| 137 | typedefs or tags; they are no longer documented and are planned to be |
| 138 | withdrawn in a future release. |
| 139 | |
| 140 | * GLR parser notes |
| 141 | |
| 142 | - GLR and inline |
| 143 | Users of Bison have to decide how they handle the portability of the |
| 144 | C keyword `inline'. |
| 145 | |
| 146 | - `parsing stack overflow...' -> `parser stack overflow' |
| 147 | GLR parsers now report `parser stack overflow' as per the Bison manual. |
| 148 | |
| 149 | * Bison now warns if it detects conflicting outputs to the same file, |
| 150 | e.g., it generates a warning for `bison -d -o foo.h foo.y' since |
| 151 | that command outputs both code and header to foo.h. |
| 152 | |
| 153 | * #line in output files |
| 154 | - --no-line works properly. |
| 155 | |
| 156 | * Bison can no longer be built by a K&R C compiler; it requires C89 or |
| 157 | later to be built. This change originally took place a few versions |
| 158 | ago, but nobody noticed until we recently asked someone to try |
| 159 | building Bison with a K&R C compiler. |
| 160 | \f |
| 161 | Changes in version 1.75, 2002-10-14: |
| 162 | |
| 163 | * Bison should now work on 64-bit hosts. |
| 164 | |
| 165 | * Indonesian translation thanks to Tedi Heriyanto. |
| 166 | |
| 167 | * GLR parsers |
| 168 | Fix spurious parse errors. |
| 169 | |
| 170 | * Pure parsers |
| 171 | Some people redefine yyerror to steal yyparse' private variables. |
| 172 | Reenable this trick until an official feature replaces it. |
| 173 | |
| 174 | * Type Clashes |
| 175 | In agreement with POSIX and with other Yaccs, leaving a default |
| 176 | action is valid when $$ is untyped, and $1 typed: |
| 177 | |
| 178 | untyped: ... typed; |
| 179 | |
| 180 | but the converse remains an error: |
| 181 | |
| 182 | typed: ... untyped; |
| 183 | |
| 184 | * Values of mid-rule actions |
| 185 | The following code: |
| 186 | |
| 187 | foo: { ... } { $$ = $1; } ... |
| 188 | |
| 189 | was incorrectly rejected: $1 is defined in the second mid-rule |
| 190 | action, and is equal to the $$ of the first mid-rule action. |
| 191 | \f |
| 192 | Changes in version 1.50, 2002-10-04: |
| 193 | |
| 194 | * GLR parsing |
| 195 | The declaration |
| 196 | %glr-parser |
| 197 | causes Bison to produce a Generalized LR (GLR) parser, capable of handling |
| 198 | almost any context-free grammar, ambiguous or not. The new declarations |
| 199 | %dprec and %merge on grammar rules allow parse-time resolution of |
| 200 | ambiguities. Contributed by Paul Hilfinger. |
| 201 | |
| 202 | Unfortunately Bison 1.50 does not work properly on 64-bit hosts |
| 203 | like the Alpha, so please stick to 32-bit hosts for now. |
| 204 | |
| 205 | * Output Directory |
| 206 | When not in Yacc compatibility mode, when the output file was not |
| 207 | specified, running `bison foo/bar.y' created `foo/bar.c'. It |
| 208 | now creates `bar.c'. |
| 209 | |
| 210 | * Undefined token |
| 211 | The undefined token was systematically mapped to 2 which prevented |
| 212 | the use of 2 by the user. This is no longer the case. |
| 213 | |
| 214 | * Unknown token numbers |
| 215 | If yylex returned an out of range value, yyparse could die. This is |
| 216 | no longer the case. |
| 217 | |
| 218 | * Error token |
| 219 | According to POSIX, the error token must be 256. |
| 220 | Bison extends this requirement by making it a preference: *if* the |
| 221 | user specified that one of her tokens is numbered 256, then error |
| 222 | will be mapped onto another number. |
| 223 | |
| 224 | * Verbose error messages |
| 225 | They no longer report `..., expecting error or...' for states where |
| 226 | error recovery is possible. |
| 227 | |
| 228 | * End token |
| 229 | Defaults to `$end' instead of `$'. |
| 230 | |
| 231 | * Error recovery now conforms to documentation and to POSIX |
| 232 | When a Bison-generated parser encounters a syntax error, it now pops |
| 233 | the stack until it finds a state that allows shifting the error |
| 234 | token. Formerly, it popped the stack until it found a state that |
| 235 | allowed some non-error action other than a default reduction on the |
| 236 | error token. The new behavior has long been the documented behavior, |
| 237 | and has long been required by POSIX. For more details, please see |
| 238 | Paul Eggert, "Reductions during Bison error handling" (2002-05-20) |
| 239 | <http://lists.gnu.org/archive/html/bug-bison/2002-05/msg00038.html>. |
| 240 | |
| 241 | * Traces |
| 242 | Popped tokens and nonterminals are now reported. |
| 243 | |
| 244 | * Larger grammars |
| 245 | Larger grammars are now supported (larger token numbers, larger grammar |
| 246 | size (= sum of the LHS and RHS lengths), larger LALR tables). |
| 247 | Formerly, many of these numbers ran afoul of 16-bit limits; |
| 248 | now these limits are 32 bits on most hosts. |
| 249 | |
| 250 | * Explicit initial rule |
| 251 | Bison used to play hacks with the initial rule, which the user does |
| 252 | not write. It is now explicit, and visible in the reports and |
| 253 | graphs as rule 0. |
| 254 | |
| 255 | * Useless rules |
| 256 | Before, Bison reported the useless rules, but, although not used, |
| 257 | included them in the parsers. They are now actually removed. |
| 258 | |
| 259 | * Useless rules, useless nonterminals |
| 260 | They are now reported, as a warning, with their locations. |
| 261 | |
| 262 | * Rules never reduced |
| 263 | Rules that can never be reduced because of conflicts are now |
| 264 | reported. |
| 265 | |
| 266 | * Incorrect `Token not used' |
| 267 | On a grammar such as |
| 268 | |
| 269 | %token useless useful |
| 270 | %% |
| 271 | exp: '0' %prec useful; |
| 272 | |
| 273 | where a token was used to set the precedence of the last rule, |
| 274 | bison reported both `useful' and `useless' as useless tokens. |
| 275 | |
| 276 | * Revert the C++ namespace changes introduced in 1.31 |
| 277 | as they caused too many portability hassles. |
| 278 | |
| 279 | * Default locations |
| 280 | By an accident of design, the default computation of @$ was |
| 281 | performed after another default computation was performed: @$ = @1. |
| 282 | The latter is now removed: YYLLOC_DEFAULT is fully responsible of |
| 283 | the computation of @$. |
| 284 | |
| 285 | * Token end-of-file |
| 286 | The token end of file may be specified by the user, in which case, |
| 287 | the user symbol is used in the reports, the graphs, and the verbose |
| 288 | error messages instead of `$end', which remains being the default. |
| 289 | For instance |
| 290 | %token MYEOF 0 |
| 291 | or |
| 292 | %token MYEOF 0 "end of file" |
| 293 | |
| 294 | * Semantic parser |
| 295 | This old option, which has been broken for ages, is removed. |
| 296 | |
| 297 | * New translations |
| 298 | Brazilian Portuguese, thanks to Alexandre Folle de Menezes. |
| 299 | Croatian, thanks to Denis Lackovic. |
| 300 | |
| 301 | * Incorrect token definitions |
| 302 | When given `%token 'a' "A"', Bison used to output `#define 'a' 65'. |
| 303 | |
| 304 | * Token definitions as enums |
| 305 | Tokens are output both as the traditional #define's, and, provided |
| 306 | the compiler supports ANSI C or is a C++ compiler, as enums. |
| 307 | This lets debuggers display names instead of integers. |
| 308 | |
| 309 | * Reports |
| 310 | In addition to --verbose, bison supports --report=THINGS, which |
| 311 | produces additional information: |
| 312 | - itemset |
| 313 | complete the core item sets with their closure |
| 314 | - lookahead [changed to `look-ahead' in 1.875e and later] |
| 315 | explicitly associate look-ahead tokens to items |
| 316 | - solved |
| 317 | describe shift/reduce conflicts solving. |
| 318 | Bison used to systematically output this information on top of |
| 319 | the report. Solved conflicts are now attached to their states. |
| 320 | |
| 321 | * Type clashes |
| 322 | Previous versions don't complain when there is a type clash on |
| 323 | the default action if the rule has a mid-rule action, such as in: |
| 324 | |
| 325 | %type <foo> bar |
| 326 | %% |
| 327 | bar: '0' {} '0'; |
| 328 | |
| 329 | This is fixed. |
| 330 | |
| 331 | * GNU M4 is now required when using Bison. |
| 332 | \f |
| 333 | Changes in version 1.35, 2002-03-25: |
| 334 | |
| 335 | * C Skeleton |
| 336 | Some projects use Bison's C parser with C++ compilers, and define |
| 337 | YYSTYPE as a class. The recent adjustment of C parsers for data |
| 338 | alignment and 64 bit architectures made this impossible. |
| 339 | |
| 340 | Because for the time being no real solution for C++ parser |
| 341 | generation exists, kludges were implemented in the parser to |
| 342 | maintain this use. In the future, when Bison has C++ parsers, this |
| 343 | kludge will be disabled. |
| 344 | |
| 345 | This kludge also addresses some C++ problems when the stack was |
| 346 | extended. |
| 347 | \f |
| 348 | Changes in version 1.34, 2002-03-12: |
| 349 | |
| 350 | * File name clashes are detected |
| 351 | $ bison foo.y -d -o foo.x |
| 352 | fatal error: header and parser would both be named `foo.x' |
| 353 | |
| 354 | * A missing `;' at the end of a rule triggers a warning |
| 355 | In accordance with POSIX, and in agreement with other |
| 356 | Yacc implementations, Bison will mandate this semicolon in the near |
| 357 | future. This eases the implementation of a Bison parser of Bison |
| 358 | grammars by making this grammar LALR(1) instead of LR(2). To |
| 359 | facilitate the transition, this release introduces a warning. |
| 360 | |
| 361 | * Revert the C++ namespace changes introduced in 1.31, as they caused too |
| 362 | many portability hassles. |
| 363 | |
| 364 | * DJGPP support added. |
| 365 | |
| 366 | * Fix test suite portability problems. |
| 367 | \f |
| 368 | Changes in version 1.33, 2002-02-07: |
| 369 | |
| 370 | * Fix C++ issues |
| 371 | Groff could not be compiled for the definition of size_t was lacking |
| 372 | under some conditions. |
| 373 | |
| 374 | * Catch invalid @n |
| 375 | As is done with $n. |
| 376 | \f |
| 377 | Changes in version 1.32, 2002-01-23: |
| 378 | |
| 379 | * Fix Yacc output file names |
| 380 | |
| 381 | * Portability fixes |
| 382 | |
| 383 | * Italian, Dutch translations |
| 384 | \f |
| 385 | Changes in version 1.31, 2002-01-14: |
| 386 | |
| 387 | * Many Bug Fixes |
| 388 | |
| 389 | * GNU Gettext and %expect |
| 390 | GNU Gettext asserts 10 s/r conflicts, but there are 7. Now that |
| 391 | Bison dies on incorrect %expectations, we fear there will be |
| 392 | too many bug reports for Gettext, so _for the time being_, %expect |
| 393 | does not trigger an error when the input file is named `plural.y'. |
| 394 | |
| 395 | * Use of alloca in parsers |
| 396 | If YYSTACK_USE_ALLOCA is defined to 0, then the parsers will use |
| 397 | malloc exclusively. Since 1.29, but was not NEWS'ed. |
| 398 | |
| 399 | alloca is used only when compiled with GCC, to avoid portability |
| 400 | problems as on AIX. |
| 401 | |
| 402 | * When the generated parser lacks debugging code, YYDEBUG is now 0 |
| 403 | (as POSIX requires) instead of being undefined. |
| 404 | |
| 405 | * User Actions |
| 406 | Bison has always permitted actions such as { $$ = $1 }: it adds the |
| 407 | ending semicolon. Now if in Yacc compatibility mode, the semicolon |
| 408 | is no longer output: one has to write { $$ = $1; }. |
| 409 | |
| 410 | * Better C++ compliance |
| 411 | The output parsers try to respect C++ namespaces. |
| 412 | [This turned out to be a failed experiment, and it was reverted later.] |
| 413 | |
| 414 | * Reduced Grammars |
| 415 | Fixed bugs when reporting useless nonterminals. |
| 416 | |
| 417 | * 64 bit hosts |
| 418 | The parsers work properly on 64 bit hosts. |
| 419 | |
| 420 | * Error messages |
| 421 | Some calls to strerror resulted in scrambled or missing error messages. |
| 422 | |
| 423 | * %expect |
| 424 | When the number of shift/reduce conflicts is correct, don't issue |
| 425 | any warning. |
| 426 | |
| 427 | * The verbose report includes the rule line numbers. |
| 428 | |
| 429 | * Rule line numbers are fixed in traces. |
| 430 | |
| 431 | * Swedish translation |
| 432 | |
| 433 | * Parse errors |
| 434 | Verbose parse error messages from the parsers are better looking. |
| 435 | Before: parse error: unexpected `'/'', expecting `"number"' or `'-'' or `'('' |
| 436 | Now: parse error: unexpected '/', expecting "number" or '-' or '(' |
| 437 | |
| 438 | * Fixed parser memory leaks. |
| 439 | When the generated parser was using malloc to extend its stacks, the |
| 440 | previous allocations were not freed. |
| 441 | |
| 442 | * Fixed verbose output file. |
| 443 | Some newlines were missing. |
| 444 | Some conflicts in state descriptions were missing. |
| 445 | |
| 446 | * Fixed conflict report. |
| 447 | Option -v was needed to get the result. |
| 448 | |
| 449 | * %expect |
| 450 | Was not used. |
| 451 | Mismatches are errors, not warnings. |
| 452 | |
| 453 | * Fixed incorrect processing of some invalid input. |
| 454 | |
| 455 | * Fixed CPP guards: 9foo.h uses BISON_9FOO_H instead of 9FOO_H. |
| 456 | |
| 457 | * Fixed some typos in the documentation. |
| 458 | |
| 459 | * %token MY_EOF 0 is supported. |
| 460 | Before, MY_EOF was silently renumbered as 257. |
| 461 | |
| 462 | * doc/refcard.tex is updated. |
| 463 | |
| 464 | * %output, %file-prefix, %name-prefix. |
| 465 | New. |
| 466 | |
| 467 | * --output |
| 468 | New, aliasing `--output-file'. |
| 469 | \f |
| 470 | Changes in version 1.30, 2001-10-26: |
| 471 | |
| 472 | * `--defines' and `--graph' have now an optional argument which is the |
| 473 | output file name. `-d' and `-g' do not change; they do not take any |
| 474 | argument. |
| 475 | |
| 476 | * `%source_extension' and `%header_extension' are removed, failed |
| 477 | experiment. |
| 478 | |
| 479 | * Portability fixes. |
| 480 | \f |
| 481 | Changes in version 1.29, 2001-09-07: |
| 482 | |
| 483 | * The output file does not define const, as this caused problems when used |
| 484 | with common autoconfiguration schemes. If you still use ancient compilers |
| 485 | that lack const, compile with the equivalent of the C compiler option |
| 486 | `-Dconst='. autoconf's AC_C_CONST macro provides one way to do this. |
| 487 | |
| 488 | * Added `-g' and `--graph'. |
| 489 | |
| 490 | * The Bison manual is now distributed under the terms of the GNU FDL. |
| 491 | |
| 492 | * The input and the output files has automatically a similar extension. |
| 493 | |
| 494 | * Russian translation added. |
| 495 | |
| 496 | * NLS support updated; should hopefully be less troublesome. |
| 497 | |
| 498 | * Added the old Bison reference card. |
| 499 | |
| 500 | * Added `--locations' and `%locations'. |
| 501 | |
| 502 | * Added `-S' and `--skeleton'. |
| 503 | |
| 504 | * `%raw', `-r', `--raw' is disabled. |
| 505 | |
| 506 | * Special characters are escaped when output. This solves the problems |
| 507 | of the #line lines with path names including backslashes. |
| 508 | |
| 509 | * New directives. |
| 510 | `%yacc', `%fixed_output_files', `%defines', `%no_parser', `%verbose', |
| 511 | `%debug', `%source_extension' and `%header_extension'. |
| 512 | |
| 513 | * @$ |
| 514 | Automatic location tracking. |
| 515 | \f |
| 516 | Changes in version 1.28, 1999-07-06: |
| 517 | |
| 518 | * Should compile better now with K&R compilers. |
| 519 | |
| 520 | * Added NLS. |
| 521 | |
| 522 | * Fixed a problem with escaping the double quote character. |
| 523 | |
| 524 | * There is now a FAQ. |
| 525 | \f |
| 526 | Changes in version 1.27: |
| 527 | |
| 528 | * The make rule which prevented bison.simple from being created on |
| 529 | some systems has been fixed. |
| 530 | \f |
| 531 | Changes in version 1.26: |
| 532 | |
| 533 | * Bison now uses automake. |
| 534 | |
| 535 | * New mailing lists: <bug-bison@gnu.org> and <help-bison@gnu.org>. |
| 536 | |
| 537 | * Token numbers now start at 257 as previously documented, not 258. |
| 538 | |
| 539 | * Bison honors the TMPDIR environment variable. |
| 540 | |
| 541 | * A couple of buffer overruns have been fixed. |
| 542 | |
| 543 | * Problems when closing files should now be reported. |
| 544 | |
| 545 | * Generated parsers should now work even on operating systems which do |
| 546 | not provide alloca(). |
| 547 | \f |
| 548 | Changes in version 1.25, 1995-10-16: |
| 549 | |
| 550 | * Errors in the input grammar are not fatal; Bison keeps reading |
| 551 | the grammar file, and reports all the errors found in it. |
| 552 | |
| 553 | * Tokens can now be specified as multiple-character strings: for |
| 554 | example, you could use "<=" for a token which looks like <=, instead |
| 555 | of chosing a name like LESSEQ. |
| 556 | |
| 557 | * The %token_table declaration says to write a table of tokens (names |
| 558 | and numbers) into the parser file. The yylex function can use this |
| 559 | table to recognize multiple-character string tokens, or for other |
| 560 | purposes. |
| 561 | |
| 562 | * The %no_lines declaration says not to generate any #line preprocessor |
| 563 | directives in the parser file. |
| 564 | |
| 565 | * The %raw declaration says to use internal Bison token numbers, not |
| 566 | Yacc-compatible token numbers, when token names are defined as macros. |
| 567 | |
| 568 | * The --no-parser option produces the parser tables without including |
| 569 | the parser engine; a project can now use its own parser engine. |
| 570 | The actions go into a separate file called NAME.act, in the form of |
| 571 | a switch statement body. |
| 572 | \f |
| 573 | Changes in version 1.23: |
| 574 | |
| 575 | The user can define YYPARSE_PARAM as the name of an argument to be |
| 576 | passed into yyparse. The argument should have type void *. It should |
| 577 | actually point to an object. Grammar actions can access the variable |
| 578 | by casting it to the proper pointer type. |
| 579 | |
| 580 | Line numbers in output file corrected. |
| 581 | \f |
| 582 | Changes in version 1.22: |
| 583 | |
| 584 | --help option added. |
| 585 | \f |
| 586 | Changes in version 1.20: |
| 587 | |
| 588 | Output file does not redefine const for C++. |
| 589 | |
| 590 | Local Variables: |
| 591 | mode: outline |
| 592 | End: |
| 593 | |
| 594 | ----- |
| 595 | |
| 596 | Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 |
| 597 | Free Software Foundation, Inc. |
| 598 | |
| 599 | This file is part of Bison, the GNU Compiler Compiler. |
| 600 | |
| 601 | Bison is free software; you can redistribute it and/or modify |
| 602 | it under the terms of the GNU General Public License as published by |
| 603 | the Free Software Foundation; either version 2, or (at your option) |
| 604 | any later version. |
| 605 | |
| 606 | Bison is distributed in the hope that it will be useful, |
| 607 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 608 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 609 | GNU General Public License for more details. |
| 610 | |
| 611 | You should have received a copy of the GNU General Public License |
| 612 | along with autoconf; see the file COPYING. If not, write to |
| 613 | the Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 614 | Boston, MA 02111-1307, USA. |