data/bison.m4

   1                                                             -*- Autoconf -*-
   2
   3 # Language-independent M4 Macros for Bison.
   4
   5 # Copyright (C) 2002, 2004-2012 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
  21 ## ---------------- ##
  22 ## Identification.  ##
  23 ## ---------------- ##
  24
  25 # b4_copyright(TITLE, YEARS)
  26 # --------------------------
  27 m4_define([b4_copyright],
  28 [b4_comment([A Bison parser, made by GNU Bison b4_version.])
  29
  30 b4_comment([$1
  31
  32 m4_text_wrap([Copyright (C) $2 Free Software Foundation, Inc.], [   ])
  33
  34 This program is free software: you can redistribute it and/or modify
  35 it under the terms of the GNU General Public License as published by
  36 the Free Software Foundation, either version 3 of the License, or
  37 (at your option) any later version.
  38
  39 This program is distributed in the hope that it will be useful,
  40 but WITHOUT ANY WARRANTY; without even the implied warranty of
  41 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  42 GNU General Public License for more details.
  43
  44 You should have received a copy of the GNU General Public License
  45 along with this program.  If not, see <http://www.gnu.org/licenses/>.])
  46
  47 b4_comment([As a special exception, you may create a larger work that contains
  48 part or all of the Bison parser skeleton and distribute that work
  49 under terms of your choice, so long as that work isn't itself a
  50 parser generator using the skeleton or a modified version thereof
  51 as a parser skeleton.  Alternatively, if you modify or redistribute
  52 the parser skeleton itself, you may (at your option) remove this
  53 special exception, which will cause the skeleton and the resulting
  54 Bison output files to be licensed under the GNU General Public
  55 License without this special exception.
  56
  57 This special exception was added by the Free Software Foundation in
  58 version 2.2 of Bison.])])
  59
  60
  61 ## ---------------- ##
  62 ## Error handling.  ##
  63 ## ---------------- ##
  64
  65 # The following error handling macros print error directives that should not
  66 # become arguments of other macro invocations since they would likely then be
  67 # mangled.  Thus, they print to stdout directly.
  68
  69 # b4_cat(TEXT)
  70 # ------------
  71 # Write TEXT to stdout.  Precede the final newline with an @ so that it's
  72 # escaped.  For example:
  73 #
  74 #   b4_cat([[@complain(invalid input@)]])
  75 m4_define([b4_cat],
  76 [m4_syscmd([cat <<'_m4eof'
  77 ]m4_bpatsubst(m4_dquote($1), [_m4eof], [_m4@`eof])[@
  78 _m4eof
  79 ])dnl
  80 m4_if(m4_sysval, [0], [], [m4_fatal([$0: cannot write to stdout])])])
  81
  82 # b4_error(KIND, FORMAT, [ARG1], [ARG2], ...)
  83 # -------------------------------------------
  84 # Write @KIND(FORMAT@,ARG1@,ARG2@,...@) to stdout.
  85 #
  86 # For example:
  87 #
  88 #   b4_error([[warn]], [[invalid value for `%s': %s]], [[foo]], [[3]])
  89 m4_define([b4_error],
  90 [b4_cat([[@]$1[(]$2[]]dnl
  91 [m4_if([$#], [2], [],
  92        [m4_foreach([b4_arg],
  93                    m4_dquote(m4_shift(m4_shift($@))),
  94                    [[@,]b4_arg])])[@)]])])
  95
  96 # b4_error_at(KIND, START, END, FORMAT, [ARG1], [ARG2], ...)
  97 # ----------------------------------------------------------
  98 # Write @KIND_at(START@,END@,FORMAT@,ARG1@,ARG2@,...@) to stdout.
  99 #
 100 # For example:
 101 #
 102 #   b4_error_at([[complain]], [[input.y:2.3]], [[input.y:5.4]],
 103 #               [[invalid %s]], [[foo]])
 104 m4_define([b4_error_at],
 105 [b4_cat([[@]$1[_at(]$2[@,]$3[@,]$4[]]dnl
 106 [m4_if([$#], [4], [],
 107        [m4_foreach([b4_arg],
 108                    m4_dquote(m4_shift(m4_shift(m4_shift(m4_shift($@))))),
 109                    [[@,]b4_arg])])[@)]])])
 110
 111 # b4_warn(FORMAT, [ARG1], [ARG2], ...)
 112 # ------------------------------------
 113 # Write @warn(FORMAT@,ARG1@,ARG2@,...@) to stdout.
 114 #
 115 # For example:
 116 #
 117 #   b4_warn([[invalid value for `%s': %s]], [[foo]], [[3]])
 118 #
 119 # As a simple test suite, this:
 120 #
 121 #   m4_divert(-1)
 122 #   m4_define([asdf], [ASDF])
 123 #   m4_define([fsa], [FSA])
 124 #   m4_define([fdsa], [FDSA])
 125 #   b4_warn([[[asdf), asdf]]], [[[fsa), fsa]]], [[[fdsa), fdsa]]])
 126 #   b4_warn([[asdf), asdf]], [[fsa), fsa]], [[fdsa), fdsa]])
 127 #   b4_warn()
 128 #   b4_warn(1)
 129 #   b4_warn(1, 2)
 130 #
 131 # Should produce this without newlines:
 132 #
 133 #   @warn([asdf), asdf]@,[fsa), fsa]@,[fdsa), fdsa]@)
 134 #   @warn(asdf), asdf@,fsa), fsa@,fdsa), fdsa@)
 135 #   @warn(@)
 136 #   @warn(1@)
 137 #   @warn(1@,2@)
 138 m4_define([b4_warn],
 139 [b4_error([[warn]], $@)])
 140
 141 # b4_warn_at(START, END, FORMAT, [ARG1], [ARG2], ...)
 142 # ---------------------------------------------------
 143 # Write @warn(START@,END@,FORMAT@,ARG1@,ARG2@,...@) to stdout.
 144 #
 145 # For example:
 146 #
 147 #   b4_warn_at([[input.y:2.3]], [[input.y:5.4]], [[invalid %s]], [[foo]])
 148 m4_define([b4_warn_at],
 149 [b4_error_at([[warn]], $@)])
 150
 151 # b4_complain(FORMAT, [ARG1], [ARG2], ...)
 152 # ----------------------------------------
 153 # Write @complain(FORMAT@,ARG1@,ARG2@,...@) to stdout.
 154 #
 155 # See b4_warn example.
 156 m4_define([b4_complain],
 157 [b4_error([[complain]], $@)])
 158
 159 # b4_complain_at(START, END, FORMAT, [ARG1], [ARG2], ...)
 160 # -------------------------------------------------------
 161 # Write @complain(START@,END@,FORMAT@,ARG1@,ARG2@,...@) to stdout.
 162 #
 163 # See b4_warn_at example.
 164 m4_define([b4_complain_at],
 165 [b4_error_at([[complain]], $@)])
 166
 167 # b4_fatal(FORMAT, [ARG1], [ARG2], ...)
 168 # -------------------------------------
 169 # Write @fatal(FORMAT@,ARG1@,ARG2@,...@) to stdout and exit.
 170 #
 171 # See b4_warn example.
 172 m4_define([b4_fatal],
 173 [b4_error([[fatal]], $@)dnl
 174 m4_exit(1)])
 175
 176 # b4_fatal_at(START, END, FORMAT, [ARG1], [ARG2], ...)
 177 # ----------------------------------------------------
 178 # Write @fatal(START@,END@,FORMAT@,ARG1@,ARG2@,...@) to stdout and exit.
 179 #
 180 # See b4_warn_at example.
 181 m4_define([b4_fatal_at],
 182 [b4_error_at([[fatal]], $@)dnl
 183 m4_exit(1)])
 184
 185
 186 ## ---------------- ##
 187 ## Default values.  ##
 188 ## ---------------- ##
 189
 190 # m4_define_default([b4_lex_param], [])   dnl breaks other skeletons
 191 m4_define_default([b4_pre_prologue], [])
 192 m4_define_default([b4_post_prologue], [])
 193 m4_define_default([b4_epilogue], [])
 194 m4_define_default([b4_parse_param], [])
 195
 196 # The initial column and line.
 197 m4_define_default([b4_location_initial_column], [1])
 198 m4_define_default([b4_location_initial_line],   [1])
 199
 200
 201 ## ------------ ##
 202 ## Data Types.  ##
 203 ## ------------ ##
 204
 205 # b4_ints_in(INT1, INT2, LOW, HIGH)
 206 # ---------------------------------
 207 # Return 1 iff both INT1 and INT2 are in [LOW, HIGH], 0 otherwise.
 208 m4_define([b4_ints_in],
 209 [m4_eval([$3 <= $1 && $1 <= $4 && $3 <= $2 && $2 <= $4])])
 210
 211
 212
 213 ## ------------------ ##
 214 ## Decoding options.  ##
 215 ## ------------------ ##
 216
 217 # b4_flag_if(FLAG, IF-TRUE, IF-FALSE)
 218 # -----------------------------------
 219 # Run IF-TRUE if b4_FLAG_flag is 1, IF-FALSE if FLAG is 0, otherwise fail.
 220 m4_define([b4_flag_if],
 221 [m4_case(b4_$1_flag,
 222          [0], [$3],
 223          [1], [$2],
 224          [m4_fatal([invalid $1 value: ]$1)])])
 225
 226
 227 # b4_define_flag_if(FLAG)
 228 # -----------------------
 229 # Define "b4_FLAG_if(IF-TRUE, IF-FALSE)" that depends on the
 230 # value of the Boolean FLAG.
 231 m4_define([b4_define_flag_if],
 232 [_b4_define_flag_if($[1], $[2], [$1])])
 233
 234 # _b4_define_flag_if($1, $2, FLAG)
 235 # --------------------------------
 236 # This macro works around the impossibility to define macros
 237 # inside macros, because issuing `[$1]' is not possible in M4 :(.
 238 # This sucks hard, GNU M4 should really provide M5 like $$1.
 239 m4_define([_b4_define_flag_if],
 240 [m4_if([$1$2], $[1]$[2], [],
 241        [m4_fatal([$0: Invalid arguments: $@])])dnl
 242 m4_define([b4_$3_if],
 243           [b4_flag_if([$3], [$1], [$2])])])
 244
 245
 246 # b4_FLAG_if(IF-TRUE, IF-FALSE)
 247 # -----------------------------
 248 # Expand IF-TRUE, if FLAG is true, IF-FALSE otherwise.
 249 b4_define_flag_if([defines])            # Whether headers are requested.
 250 b4_define_flag_if([error_verbose])      # Whether error are verbose.
 251 b4_define_flag_if([glr])                # Whether a GLR parser is requested.
 252 b4_define_flag_if([locations])          # Whether locations are tracked.
 253 b4_define_flag_if([nondeterministic])   # Whether conflicts should be handled.
 254 b4_define_flag_if([yacc])               # Whether POSIX Yacc is emulated.
 255
 256
 257 ## ------------------------- ##
 258 ## Assigning token numbers.  ##
 259 ## ------------------------- ##
 260
 261
 262 ## ----------- ##
 263 ## Synclines.  ##
 264 ## ----------- ##
 265
 266 # b4_basename(NAME)
 267 # -----------------
 268 # Similar to POSIX basename; the differences don't matter here.
 269 # Beware that NAME is not evaluated.
 270 m4_define([b4_basename],
 271 [m4_bpatsubst([$1], [^.*/\([^/]+\)/*$], [\1])])
 272
 273
 274 # b4_syncline(LINE, FILE)
 275 # -----------------------
 276 m4_define([b4_syncline],
 277 [b4_flag_if([synclines], [
 278 b4_sync_end([__line__], [b4_basename(m4_quote(__file__))])
 279 b4_sync_start([$1], [$2])])])
 280
 281 m4_define([b4_sync_end], [b4_comment([Line $1 of $2])])
 282 m4_define([b4_sync_start], [b4_comment([Line $1 of $2])])
 283
 284 # b4_user_code(USER-CODE)
 285 # -----------------------
 286 # Emit code from the user, ending it with synclines.
 287 m4_define([b4_user_code],
 288 [$1
 289 b4_syncline([@oline@], [@ofile@])])
 290
 291
 292 # b4_define_user_code(MACRO)
 293 # --------------------------
 294 # From b4_MACRO, build b4_user_MACRO that includes the synclines.
 295 m4_define([b4_define_user_code],
 296 [m4_define([b4_user_$1],
 297 [b4_user_code([b4_$1])])])
 298
 299
 300 # b4_user_actions
 301 # b4_user_initial_action
 302 # b4_user_post_prologue
 303 # b4_user_pre_prologue
 304 # b4_user_stype
 305 # ----------------------
 306 # Macros that issue user code, ending with synclines.
 307 b4_define_user_code([actions])
 308 b4_define_user_code([initial_action])
 309 b4_define_user_code([post_prologue])
 310 b4_define_user_code([pre_prologue])
 311 b4_define_user_code([stype])
 312
 313
 314 # b4_check_user_names(WHAT, USER-LIST, BISON-NAMESPACE)
 315 # -----------------------------------------------------
 316 # Complain if any name of type WHAT is used by the user (as recorded in
 317 # USER-LIST) but is not used by Bison (as recorded by macros in the
 318 # namespace BISON-NAMESPACE).
 319 #
 320 # USER-LIST must expand to a list specifying all user occurrences of all names
 321 # of type WHAT.   Each item in the list must be a triplet specifying one
 322 # occurrence: name, start boundary, and end boundary.  Empty string names are
 323 # fine.  An empty list is fine.
 324 #
 325 # For example, to define b4_foo_user_names to be used for USER-LIST with three
 326 # name occurrences and with correct quoting:
 327 #
 328 #   m4_define([b4_foo_user_names],
 329 #             [[[[[[bar]], [[parser.y:1.7]], [[parser.y:1.16]]]],
 330 #               [[[[bar]], [[parser.y:5.7]], [[parser.y:5.16]]]],
 331 #               [[[[baz]], [[parser.y:8.7]], [[parser.y:8.16]]]]]])
 332 #
 333 # The macro BISON-NAMESPACE(bar) must be defined iff the name bar of type WHAT
 334 # is used by Bison (in the front-end or in the skeleton).  Empty string names
 335 # are fine, but it would be ugly for Bison to actually use one.
 336 #
 337 # For example, to use b4_foo_bison_names for BISON-NAMESPACE and define that
 338 # the names bar and baz are used by Bison:
 339 #
 340 #   m4_define([b4_foo_bison_names(bar)])
 341 #   m4_define([b4_foo_bison_names(baz)])
 342 #
 343 # To invoke b4_check_user_names with TYPE foo, with USER-LIST
 344 # b4_foo_user_names, with BISON-NAMESPACE b4_foo_bison_names, and with correct
 345 # quoting:
 346 #
 347 #   b4_check_user_names([[foo]], [b4_foo_user_names],
 348 #                       [[b4_foo_bison_names]])
 349 m4_define([b4_check_user_names],
 350 [m4_foreach([b4_occurrence], $2,
 351 [m4_pushdef([b4_occurrence], b4_occurrence)dnl
 352 m4_pushdef([b4_user_name], m4_car(b4_occurrence))dnl
 353 m4_pushdef([b4_start], m4_car(m4_shift(b4_occurrence)))dnl
 354 m4_pushdef([b4_end], m4_shift(m4_shift(b4_occurrence)))dnl
 355 m4_ifndef($3[(]m4_quote(b4_user_name)[)],
 356           [b4_complain_at([b4_start], [b4_end],
 357                           [[%s `%s' is not used]],
 358                           [$1], [b4_user_name])])[]dnl
 359 m4_popdef([b4_occurrence])dnl
 360 m4_popdef([b4_user_name])dnl
 361 m4_popdef([b4_start])dnl
 362 m4_popdef([b4_end])dnl
 363 ])])
 364
 365
 366
 367
 368 ## --------------------- ##
 369 ## b4_percent_define_*.  ##
 370 ## --------------------- ##
 371
 372
 373 # b4_percent_define_use(VARIABLE)
 374 # -------------------------------
 375 # Declare that VARIABLE was used.
 376 m4_define([b4_percent_define_use],
 377 [m4_define([b4_percent_define_bison_variables(]$1[)])dnl
 378 ])
 379
 380 # b4_percent_define_get(VARIABLE, [DEFAULT])
 381 # ------------------------------------------
 382 # Mimic muscle_percent_define_get in ../src/muscle-tab.h.  That is, if
 383 # the %define variable VARIABLE is defined, emit its value.  Contrary
 384 # to its C counterpart, return DEFAULT otherwise.  Also, record
 385 # Bison's usage of VARIABLE by defining
 386 # b4_percent_define_bison_variables(VARIABLE).
 387 #
 388 # For example:
 389 #
 390 #   b4_percent_define_get([[foo]])
 391 m4_define([b4_percent_define_get],
 392 [b4_percent_define_use([$1])dnl
 393 m4_ifdef([b4_percent_define(]$1[)],
 394          [m4_indir([b4_percent_define(]$1[)])],
 395          [$2])])
 396
 397
 398 # b4_percent_define_get_loc(VARIABLE)
 399 # -----------------------------------
 400 # Mimic muscle_percent_define_get_loc in ../src/muscle-tab.h exactly.  That is,
 401 # if the %define variable VARIABLE is undefined, complain fatally since that's
 402 # a Bison or skeleton error.  Otherwise, return its definition location in a
 403 # form approriate for the first two arguments of b4_warn_at, b4_complain_at, or
 404 # b4_fatal_at.  Don't record this as a Bison usage of VARIABLE as there's no
 405 # reason to suspect that the user-supplied value has yet influenced the output.
 406 #
 407 # For example:
 408 #
 409 #   b4_complain_at(b4_percent_define_get_loc([[foo]]), [[invalid foo]])
 410 m4_define([b4_percent_define_get_loc],
 411 [m4_ifdef([b4_percent_define_loc(]$1[)],
 412           [m4_pushdef([b4_loc], m4_indir([b4_percent_define_loc(]$1[)]))dnl
 413 b4_loc[]dnl
 414 m4_popdef([b4_loc])],
 415           [b4_fatal([[undefined %%define variable `%s' passed to b4_percent_define_get_loc]], [$1])])])
 416
 417 # b4_percent_define_get_syncline(VARIABLE)
 418 # ----------------------------------------
 419 # Mimic muscle_percent_define_get_syncline in ../src/muscle-tab.h exactly.
 420 # That is, if the %define variable VARIABLE is undefined, complain fatally
 421 # since that's a Bison or skeleton error.  Otherwise, return its definition
 422 # location as a b4_syncline invocation.  Don't record this as a Bison usage of
 423 # VARIABLE as there's no reason to suspect that the user-supplied value has yet
 424 # influenced the output.
 425 #
 426 # For example:
 427 #
 428 #   b4_percent_define_get_syncline([[foo]])
 429 m4_define([b4_percent_define_get_syncline],
 430 [m4_ifdef([b4_percent_define_syncline(]$1[)],
 431           [m4_indir([b4_percent_define_syncline(]$1[)])],
 432           [b4_fatal([[undefined %%define variable `%s' passed to b4_percent_define_get_syncline]], [$1])])])
 433
 434 # b4_percent_define_ifdef(VARIABLE, IF-TRUE, [IF-FALSE])
 435 # ------------------------------------------------------
 436 # Mimic muscle_percent_define_ifdef in ../src/muscle-tab.h exactly.  That is,
 437 # if the %define variable VARIABLE is defined, expand IF-TRUE, else expand
 438 # IF-FALSE.  Also, record Bison's usage of VARIABLE by defining
 439 # b4_percent_define_bison_variables(VARIABLE).
 440 #
 441 # For example:
 442 #
 443 #   b4_percent_define_ifdef([[foo]], [[it's defined]], [[it's undefined]])
 444 m4_define([b4_percent_define_ifdef],
 445 [m4_ifdef([b4_percent_define(]$1[)],
 446           [m4_define([b4_percent_define_bison_variables(]$1[)])$2],
 447           [$3])])
 448
 449 # b4_percent_define_flag_if(VARIABLE, IF-TRUE, [IF-FALSE])
 450 # --------------------------------------------------------
 451 # Mimic muscle_percent_define_flag_if in ../src/muscle-tab.h exactly.  That is,
 452 # if the %define variable VARIABLE is defined to "" or "true", expand IF-TRUE.
 453 # If it is defined to "false", expand IF-FALSE.  Complain if it is undefined
 454 # (a Bison or skeleton error since the default value should have been set
 455 # already) or defined to any other value (possibly a user error).  Also, record
 456 # Bison's usage of VARIABLE by defining
 457 # b4_percent_define_bison_variables(VARIABLE).
 458 #
 459 # For example:
 460 #
 461 #   b4_percent_define_flag_if([[foo]], [[it's true]], [[it's false]])
 462 m4_define([b4_percent_define_flag_if],
 463 [b4_percent_define_ifdef([$1],
 464   [m4_case(b4_percent_define_get([$1]),
 465            [], [$2], [true], [$2], [false], [$3],
 466            [m4_expand_once([b4_complain_at(b4_percent_define_get_loc([$1]),
 467                                            [[invalid value for %%define Boolean variable `%s']],
 468                                            [$1])],
 469                            [[b4_percent_define_flag_if($1)]])])],
 470   [b4_fatal([[undefined %%define variable `%s' passed to b4_percent_define_flag_if]], [$1])])])
 471
 472 # b4_percent_define_default(VARIABLE, DEFAULT)
 473 # --------------------------------------------
 474 # Mimic muscle_percent_define_default in ../src/muscle-tab.h exactly.  That is,
 475 # if the %define variable VARIABLE is undefined, set its value to DEFAULT.
 476 # Don't record this as a Bison usage of VARIABLE as there's no reason to
 477 # suspect that the value has yet influenced the output.
 478 #
 479 # For example:
 480 #
 481 #   b4_percent_define_default([[foo]], [[default value]])
 482 m4_define([b4_percent_define_default],
 483 [m4_ifndef([b4_percent_define(]$1[)],
 484            [m4_define([b4_percent_define(]$1[)], [$2])dnl
 485             m4_define([b4_percent_define_loc(]$1[)],
 486                       [[[[<skeleton default value>:-1.-1]],
 487                         [[<skeleton default value>:-1.-1]]]])dnl
 488             m4_define([b4_percent_define_syncline(]$1[)], [[]])])])
 489
 490 # b4_percent_define_check_values(VALUES)
 491 # --------------------------------------
 492 # Mimic muscle_percent_define_check_values in ../src/muscle-tab.h exactly
 493 # except that the VALUES structure is more appropriate for M4.  That is, VALUES
 494 # is a list of sublists of strings.  For each sublist, the first string is the
 495 # name of a %define variable, and all remaining strings in that sublist are the
 496 # valid values for that variable.  Complain if such a variable is undefined (a
 497 # Bison error since the default value should have been set already) or defined
 498 # to any other value (possibly a user error).  Don't record this as a Bison
 499 # usage of the variable as there's no reason to suspect that the value has yet
 500 # influenced the output.
 501 #
 502 # For example:
 503 #
 504 #   b4_percent_define_check_values([[[[foo]], [[foo-value1]], [[foo-value2]]]],
 505 #                                  [[[[bar]], [[bar-value1]]]])
 506 m4_define([b4_percent_define_check_values],
 507 [m4_foreach([b4_sublist], m4_quote($@),
 508             [_b4_percent_define_check_values(b4_sublist)])])
 509
 510 m4_define([_b4_percent_define_check_values],
 511 [m4_ifdef([b4_percent_define(]$1[)],
 512   [m4_pushdef([b4_good_value], [0])dnl
 513    m4_if($#, 1, [],
 514          [m4_foreach([b4_value], m4_dquote(m4_shift($@)),
 515                      [m4_if(m4_indir([b4_percent_define(]$1[)]), b4_value,
 516                             [m4_define([b4_good_value], [1])])])])dnl
 517    m4_if(b4_good_value, [0],
 518          [b4_complain_at(b4_percent_define_get_loc([$1]),
 519                          [[invalid value for %%define variable `%s': `%s']],
 520                          [$1],
 521                          m4_dquote(m4_indir([b4_percent_define(]$1[)])))
 522           m4_foreach([b4_value], m4_dquote(m4_shift($@)),
 523                      [b4_complain_at(b4_percent_define_get_loc([$1]),
 524                                      [[accepted value: `%s']],
 525                                      m4_dquote(b4_value))])])dnl
 526    m4_popdef([b4_good_value])],
 527   [b4_fatal([[undefined %%define variable `%s' passed to b4_percent_define_check_values]], [$1])])])
 528
 529 # b4_percent_code_get([QUALIFIER])
 530 # --------------------------------
 531 # If any %code blocks for QUALIFIER are defined, emit them beginning with a
 532 # comment and ending with synclines and a newline.  If QUALIFIER is not
 533 # specified or empty, do this for the unqualified %code blocks.  Also, record
 534 # Bison's usage of QUALIFIER (if specified) by defining
 535 # b4_percent_code_bison_qualifiers(QUALIFIER).
 536 #
 537 # For example, to emit any unqualified %code blocks followed by any %code
 538 # blocks for the qualifier foo:
 539 #
 540 #   b4_percent_code_get
 541 #   b4_percent_code_get([[foo]])
 542 m4_define([b4_percent_code_get],
 543 [m4_pushdef([b4_macro_name], [[b4_percent_code(]$1[)]])dnl
 544 m4_ifval([$1], [m4_define([b4_percent_code_bison_qualifiers(]$1[)])])dnl
 545 m4_ifdef(b4_macro_name,
 546 [b4_comment([m4_if([$#], [0], [[Unqualified %code]],
 547                    [["%code ]$1["]])[ blocks.]])
 548 b4_user_code([m4_indir(b4_macro_name)])
 549 ])dnl
 550 m4_popdef([b4_macro_name])])
 551
 552 # b4_percent_code_ifdef(QUALIFIER, IF-TRUE, [IF-FALSE])
 553 # -----------------------------------------------------
 554 # If any %code blocks for QUALIFIER (or unqualified %code blocks if
 555 # QUALIFIER is empty) are defined, expand IF-TRUE, else expand IF-FALSE.
 556 # Also, record Bison's usage of QUALIFIER (if specified) by defining
 557 # b4_percent_code_bison_qualifiers(QUALIFIER).
 558 m4_define([b4_percent_code_ifdef],
 559 [m4_ifdef([b4_percent_code(]$1[)],
 560           [m4_ifval([$1], [m4_define([b4_percent_code_bison_qualifiers(]$1[)])])$2],
 561           [$3])])
 562
 563
 564 ## ----------------------------------------------------------- ##
 565 ## After processing the skeletons, check that all the user's   ##
 566 ## %define variables and %code qualifiers were used by Bison.  ##
 567 ## ----------------------------------------------------------- ##
 568
 569 m4_define([b4_check_user_names_wrap],
 570 [m4_ifdef([b4_percent_]$1[_user_]$2[s],
 571           [b4_check_user_names([[%]$1 $2],
 572                                [b4_percent_]$1[_user_]$2[s],
 573                                [[b4_percent_]$1[_bison_]$2[s]])])])
 574
 575 m4_wrap_lifo([
 576 b4_check_user_names_wrap([[define]], [[variable]])
 577 b4_check_user_names_wrap([[code]], [[qualifier]])
 578 ])