perly.y

   1 /* $RCSfile: perly.y,v $$Revision: 4.1 $$Date: 92/08/07 18:26:16 $
   2  *
   3  *    Copyright (c) 1991, Larry Wall
   4  *
   5  *    You may distribute under the terms of either the GNU General Public
   6  *    License or the Artistic License, as specified in the README file.
   7  *
   8  * $Log:        perly.y,v $
   9  * Revision 4.1  92/08/07  18:26:16  lwall
  10  *
  11  * Revision 4.0.1.5  92/06/11  21:12:50  lwall
  12  * patch34: expectterm incorrectly set to indicate start of program or block
  13  *
  14  * Revision 4.0.1.4  92/06/08  17:33:25  lwall
  15  * patch20: one of the backdoors to expectterm was on the wrong reduction
  16  *
  17  * Revision 4.0.1.3  92/06/08  15:18:16  lwall
  18  * patch20: an expression may now start with a bareword
  19  * patch20: relaxed requirement for semicolon at the end of a block
  20  * patch20: added ... as variant on ..
  21  * patch20: fixed double debug break in foreach with implicit array assignment
  22  * patch20: if {block} {block} didn't work any more
  23  * patch20: deleted some minor memory leaks
  24  *
  25  * Revision 4.0.1.2  91/11/05  18:17:38  lwall
  26  * patch11: extra comma at end of list is now allowed in more places (Hi, Felix!)
  27  * patch11: once-thru blocks didn't display right in the debugger
  28  * patch11: debugger got confused over nested subroutine definitions
  29  *
  30  * Revision 4.0.1.1  91/06/07  11:42:34  lwall
  31  * patch4: new copyright notice
  32  *
  33  * Revision 4.0  91/03/20  01:38:40  lwall
  34  * 4.0 baseline.
  35  *
  36  */
  37
  38 %{
  39 #include "EXTERN.h"
  40 #include "perl.h"
  41
  42 /*SUPPRESS 530*/
  43 /*SUPPRESS 593*/
  44 /*SUPPRESS 595*/
  45
  46 %}
  47
  48 %start prog
  49
  50 %union {
  51     I32 ival;
  52     char *pval;
  53     OP *opval;
  54     GV *gvval;
  55 }
  56
  57 %token <ival> '{' ')'
  58
  59 %token <opval> WORD METHOD THING PMFUNC
  60 %token <pval> LABEL
  61 %token <ival> FORMAT SUB PACKAGE
  62 %token <ival> WHILE UNTIL IF UNLESS ELSE ELSIF CONTINUE FOR
  63 %token <ival> LOOPEX DOTDOT
  64 %token <ival> FUNC0 FUNC1 FUNC
  65 %token <ival> RELOP EQOP MULOP ADDOP
  66 %token <ival> DOLSHARP DO LOCAL DELETE HASHBRACK
  67
  68 %type <ival> prog decl format remember crp crb crhb
  69 %type <opval> block lineseq line loop cond nexpr else
  70 %type <opval> expr sexpr term scalar ary hsh arylen star amper sideff
  71 %type <opval> listexpr indirob
  72 %type <opval> texpr listop
  73 %type <pval> label
  74 %type <opval> cont
  75
  76 %nonassoc <ival> LSTOP
  77 %left ','
  78 %right '='
  79 %right '?' ':'
  80 %nonassoc DOTDOT
  81 %left OROR
  82 %left ANDAND
  83 %left <ival> BITOROP
  84 %left <ival> BITANDOP
  85 %nonassoc EQOP
  86 %nonassoc RELOP
  87 %nonassoc <ival> UNIOP
  88 %left <ival> SHIFTOP
  89 %left ADDOP
  90 %left MULOP
  91 %left <ival> MATCHOP ARROW
  92 %right '!' '~' UMINUS REFGEN
  93 %right <ival> POWOP
  94 %nonassoc PREINC PREDEC POSTINC POSTDEC
  95 %left '('
  96
  97 %% /* RULES */
  98
  99 prog    :       /* NULL */
 100                 {
 101 #if defined(YYDEBUG) && defined(DEBUGGING)
 102                     yydebug = (debug & 1);
 103 #endif
 104                     expect = XBLOCK;
 105                 }
 106         /*CONTINUED*/   lineseq
 107                         {   if (in_eval) {
 108                                 eval_root = newUNOP(OP_LEAVEEVAL, 0, $2);
 109                                 eval_start = linklist(eval_root);
 110                                 eval_root->op_next = 0;
 111                                 peep(eval_start);
 112                             }
 113                             else
 114                                 main_root = block_head(scalar($2), &main_start);
 115                         }
 116         ;
 117
 118 block   :       '{' remember lineseq '}'
 119                         { $$ = scalarseq($3);
 120                           if (copline > (line_t)$1)
 121                               copline = $1;
 122                           if (savestack_ix > $2)
 123                             leave_scope($2);
 124                           expect = XBLOCK; }
 125         ;
 126
 127 remember:       /* NULL */      /* in case they push a package name */
 128                         { $$ = savestack_ix; }
 129         ;
 130
 131 lineseq :       /* NULL */
 132                         { $$ = Nullop; }
 133         |       lineseq decl
 134                         { $$ = $1; }
 135         |       lineseq line
 136                         { $$ = append_list(OP_LINESEQ, $1, $2); pad_reset(); }
 137         ;
 138
 139 line    :       label cond
 140                         { $$ = newSTATEOP(0, $1, $2); }
 141         |       loop    /* loops add their own labels */
 142         |       label ';'
 143                         { if ($1 != Nullch) {
 144                               $$ = newSTATEOP(0, $1, newOP(OP_NULL, 0));
 145                             }
 146                             else {
 147                               $$ = Nullop;
 148                               copline = NOLINE;
 149                             }
 150                             expect = XBLOCK; }
 151         |       label sideff ';'
 152                         { $$ = newSTATEOP(0, $1, $2);
 153                           expect = XBLOCK; }
 154         ;
 155
 156 sideff  :       error
 157                         { $$ = Nullop; }
 158         |       expr
 159                         { $$ = $1; }
 160         |       expr IF expr
 161                         { $$ = newLOGOP(OP_AND, 0, $3, $1); }
 162         |       expr UNLESS expr
 163                         { $$ = newLOGOP(OP_OR, 0, $3, $1); }
 164         |       expr WHILE expr
 165                         { $$ = newLOOPOP(0, 1, scalar($3), $1, Nullop); }
 166         |       expr UNTIL expr
 167                         { $$ = newLOOPOP(0, 1, invert(scalar($3)), $1, Nullop);}
 168         ;
 169
 170 else    :       /* NULL */
 171                         { $$ = Nullop; }
 172         |       ELSE block
 173                         { $$ = scope($2); }
 174         |       ELSIF '(' expr ')' block else
 175                         { copline = $1;
 176                             $$ = newCONDOP(0, $3, scope($5), $6); }
 177         ;
 178
 179 cond    :       IF '(' expr ')' block else
 180                         { copline = $1;
 181                             $$ = newCONDOP(0, $3, scope($5), $6); }
 182         |       UNLESS '(' expr ')' block else
 183                         { copline = $1;
 184                             $$ = newCONDOP(0,
 185                                 invert(scalar($3)), scope($5), $6); }
 186         |       IF block block else
 187                         { copline = $1;
 188                             $$ = newCONDOP(0, scope($2), scope($3), $4); }
 189         |       UNLESS block block else
 190                         { copline = $1;
 191                             $$ = newCONDOP(0, invert(scalar(scope($2))),
 192                                                 scope($3), $4); }
 193         ;
 194
 195 cont    :       /* NULL */
 196                         { $$ = Nullop; }
 197         |       CONTINUE block
 198                         { $$ = scope($2); }
 199         ;
 200
 201 loop    :       label WHILE '(' texpr ')' block cont
 202                         { copline = $2;
 203                             $$ = newSTATEOP(0, $1,
 204                                     newWHILEOP(0, 1, Nullop, $4, $6, $7) ); }
 205         |       label UNTIL '(' expr ')' block cont
 206                         { copline = $2;
 207                             $$ = newSTATEOP(0, $1,
 208                                     newWHILEOP(0, 1, Nullop,
 209                                         invert(scalar($4)), $6, $7) ); }
 210         |       label WHILE block block cont
 211                         { copline = $2;
 212                             $$ = newSTATEOP(0, $1,
 213                                     newWHILEOP(0, 1, Nullop,
 214                                         scope($3), $4, $5) ); }
 215         |       label UNTIL block block cont
 216                         { copline = $2;
 217                             $$ = newSTATEOP(0, $1,
 218                                     newWHILEOP(0, 1, Nullop,
 219                                         invert(scalar(scope($3))), $4, $5)); }
 220         |       label FOR scalar '(' expr crp block cont
 221                         { $$ = newFOROP(0, $1, $2, ref($3, OP_ENTERLOOP),
 222                                 $5, $7, $8); }
 223         |       label FOR '(' expr crp block cont
 224                         { $$ = newFOROP(0, $1, $2, Nullop, $4, $6, $7); }
 225         |       label FOR '(' nexpr ';' texpr ';' nexpr ')' block
 226                         /* basically fake up an initialize-while lineseq */
 227                         {  copline = $2;
 228                             $$ = append_elem(OP_LINESEQ,
 229                                     newSTATEOP(0, $1, scalar($4)),
 230                                     newSTATEOP(0, $1,
 231                                         newWHILEOP(0, 1, Nullop,
 232                                             scalar($6), $10, scalar($8)) )); }
 233         |       label block cont  /* a block is a loop that happens once */
 234                         { $$ = newSTATEOP(0,
 235                                 $1, newWHILEOP(0, 1, Nullop, Nullop, $2, $3)); }
 236         ;
 237
 238 nexpr   :       /* NULL */
 239                         { $$ = Nullop; }
 240         |       sideff
 241         ;
 242
 243 texpr   :       /* NULL means true */
 244                         { (void)scan_num("1"); $$ = yylval.opval; }
 245         |       expr
 246         ;
 247
 248 label   :       /* empty */
 249                         { $$ = Nullch; }
 250         |       LABEL
 251         ;
 252
 253 decl    :       format
 254                         { $$ = 0; }
 255         |       subrout
 256                         { $$ = 0; }
 257         |       package
 258                         { $$ = 0; }
 259         ;
 260
 261 format  :       FORMAT WORD block
 262                         { newFORM($1, $2, $3); }
 263         |       FORMAT block
 264                         { newFORM($1, Nullop, $2); }
 265         ;
 266
 267 subrout :       SUB WORD block
 268                         { newSUB($1, $2, $3); }
 269         ;
 270
 271 package :       PACKAGE WORD ';'
 272                         { package($2); }
 273         ;
 274
 275 expr    :       expr ',' sexpr
 276                         { $$ = append_elem(OP_LIST, $1, $3); }
 277         |       sexpr
 278         ;
 279
 280 listop  :       LSTOP indirob listexpr
 281                         { $$ = convert($1, OPf_STACKED,
 282                                 prepend_elem(OP_LIST, newGVREF($2), $3) ); }
 283         |       FUNC '(' indirob listexpr ')'
 284                         { $$ = convert($1, OPf_STACKED,
 285                                 prepend_elem(OP_LIST, newGVREF($3), $4) ); }
 286         |       indirob ARROW LSTOP listexpr
 287                         { $$ = convert($3, OPf_STACKED,
 288                                 prepend_elem(OP_LIST, newGVREF($1), $4) ); }
 289         |       indirob ARROW FUNC '(' listexpr ')'
 290                         { $$ = convert($3, OPf_STACKED,
 291                                 prepend_elem(OP_LIST, newGVREF($1), $5) ); }
 292         |       term ARROW METHOD '(' listexpr ')'
 293                         { $$ = convert(OP_ENTERSUBR, OPf_STACKED|OPf_SPECIAL,
 294                                 prepend_elem(OP_LIST, newMETHOD($1,$3), $5)); }
 295         |       METHOD indirob listexpr
 296                         { $$ = convert(OP_ENTERSUBR, OPf_STACKED|OPf_SPECIAL,
 297                                 prepend_elem(OP_LIST, newMETHOD($2,$1), $3)); }
 298         |       LSTOP listexpr
 299                         { $$ = convert($1, 0, $2); }
 300         |       FUNC '(' listexpr ')'
 301                         { $$ = convert($1, 0, $3); }
 302         ;
 303
 304 sexpr   :       sexpr '=' sexpr
 305                         { $$ = newASSIGNOP(OPf_STACKED, $1, $3); }
 306         |       sexpr POWOP '=' sexpr
 307                         { $$ = newBINOP($2, OPf_STACKED,
 308                                 ref(scalar($1), $2), scalar($4)); }
 309         |       sexpr MULOP '=' sexpr
 310                         { $$ = newBINOP($2, OPf_STACKED,
 311                                 ref(scalar($1), $2), scalar($4)); }
 312         |       sexpr ADDOP '=' sexpr
 313                         { $$ = newBINOP($2, OPf_STACKED,
 314                                 ref(scalar($1), $2), scalar($4));}
 315         |       sexpr SHIFTOP '=' sexpr
 316                         { $$ = newBINOP($2, OPf_STACKED,
 317                                 ref(scalar($1), $2), scalar($4)); }
 318         |       sexpr BITANDOP '=' sexpr
 319                         { $$ = newBINOP($2, OPf_STACKED,
 320                                 ref(scalar($1), $2), scalar($4)); }
 321         |       sexpr BITOROP '=' sexpr
 322                         { $$ = newBINOP($2, OPf_STACKED,
 323                                 ref(scalar($1), $2), scalar($4)); }
 324         |       sexpr ANDAND '=' sexpr
 325                         { $$ = newLOGOP(OP_ANDASSIGN, 0,
 326                                 ref(scalar($1), OP_ANDASSIGN),
 327                                 newUNOP(OP_SASSIGN, 0, scalar($4))); }
 328         |       sexpr OROR '=' sexpr
 329                         { $$ = newLOGOP(OP_ORASSIGN, 0,
 330                                 ref(scalar($1), OP_ORASSIGN),
 331                                 newUNOP(OP_SASSIGN, 0, scalar($4))); }
 332
 333
 334         |       sexpr POWOP sexpr
 335                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 336         |       sexpr MULOP sexpr
 337                         {   if ($2 != OP_REPEAT)
 338                                 scalar($1);
 339                             $$ = newBINOP($2, 0, $1, scalar($3)); }
 340         |       sexpr ADDOP sexpr
 341                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 342         |       sexpr SHIFTOP sexpr
 343                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 344         |       sexpr RELOP sexpr
 345                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 346         |       sexpr EQOP sexpr
 347                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 348         |       sexpr BITANDOP sexpr
 349                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 350         |       sexpr BITOROP sexpr
 351                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 352         |       sexpr DOTDOT sexpr
 353                         { $$ = newRANGE($2, scalar($1), scalar($3));}
 354         |       sexpr ANDAND sexpr
 355                         { $$ = newLOGOP(OP_AND, 0, $1, $3); }
 356         |       sexpr OROR sexpr
 357                         { $$ = newLOGOP(OP_OR, 0, $1, $3); }
 358         |       sexpr '?' sexpr ':' sexpr
 359                         { $$ = newCONDOP(0, $1, $3, $5); }
 360         |       sexpr MATCHOP sexpr
 361                         { $$ = bind_match($2, $1, $3); }
 362         |       term
 363                         { $$ = $1; }
 364         ;
 365
 366 term    :       '-' term %prec UMINUS
 367                         { $$ = newUNOP(OP_NEGATE, 0, scalar($2)); }
 368         |       '+' term %prec UMINUS
 369                         { $$ = $2; }
 370         |       '!' term
 371                         { $$ = newUNOP(OP_NOT, 0, scalar($2)); }
 372         |       '~' term
 373                         { $$ = newUNOP(OP_COMPLEMENT, 0, scalar($2));}
 374         |       REFGEN term
 375                         { $$ = newUNOP(OP_REFGEN, 0, ref($2, OP_REFGEN)); }
 376         |       term POSTINC
 377                         { $$ = newUNOP(OP_POSTINC, 0,
 378                                         ref(scalar($1), OP_POSTINC)); }
 379         |       term POSTDEC
 380                         { $$ = newUNOP(OP_POSTDEC, 0,
 381                                         ref(scalar($1), OP_POSTDEC)); }
 382         |       PREINC term
 383                         { $$ = newUNOP(OP_PREINC, 0,
 384                                         ref(scalar($2), OP_PREINC)); }
 385         |       PREDEC term
 386                         { $$ = newUNOP(OP_PREDEC, 0,
 387                                         ref(scalar($2), OP_PREDEC)); }
 388         |       LOCAL sexpr     %prec UNIOP
 389                         { $$ = localize($2); }
 390         |       '(' expr crp
 391                         { $$ = sawparens($2); }
 392         |       '(' ')'
 393                         { $$ = newNULLLIST(); }
 394         |       '[' expr crb                            %prec '('
 395                         { $$ = newANONLIST($2); }
 396         |       '[' ']'                                 %prec '('
 397                         { $$ = newANONLIST(Nullop); }
 398         |       HASHBRACK expr crhb                     %prec '('
 399                         { $$ = newANONHASH($2); }
 400         |       HASHBRACK ';' '}'                               %prec '('
 401                         { $$ = newANONHASH(Nullop); }
 402         |       scalar  %prec '('
 403                         { $$ = $1; }
 404         |       star    %prec '('
 405                         { $$ = $1; }
 406         |       scalar '[' expr ']'     %prec '('
 407                         { $$ = newBINOP(OP_AELEM, 0, oopsAV($1), scalar($3)); }
 408         |       term ARROW '[' expr ']' %prec '('
 409                         { $$ = newBINOP(OP_AELEM, 0,
 410                                         scalar(ref(newAVREF($1),OP_RV2AV)),
 411                                         scalar($4));}
 412         |       hsh     %prec '('
 413                         { $$ = $1; }
 414         |       ary     %prec '('
 415                         { $$ = $1; }
 416         |       arylen  %prec '('
 417                         { $$ = newUNOP(OP_AV2ARYLEN, 0, ref($1, OP_AV2ARYLEN));}
 418         |       scalar '{' expr ';' '}' %prec '('
 419                         { $$ = newBINOP(OP_HELEM, 0, oopsHV($1), jmaybe($3));
 420                             expect = XOPERATOR; }
 421         |       term ARROW '{' expr ';' '}'     %prec '('
 422                         { $$ = newBINOP(OP_HELEM, 0,
 423                                         scalar(ref(newHVREF($1),OP_RV2HV)),
 424                                         jmaybe($4));
 425                             expect = XOPERATOR; }
 426         |       '(' expr crp '[' expr ']'       %prec '('
 427                         { $$ = newSLICEOP(0, $5, $2); }
 428         |       '(' ')' '[' expr ']'    %prec '('
 429                         { $$ = newSLICEOP(0, $4, Nullop); }
 430         |       ary '[' expr ']'        %prec '('
 431                         { $$ = prepend_elem(OP_ASLICE,
 432                                 newOP(OP_PUSHMARK, 0),
 433                                 list(
 434                                     newLISTOP(OP_ASLICE, 0,
 435                                         list($3),
 436                                         ref($1, OP_ASLICE)))); }
 437         |       ary '{' expr ';' '}'    %prec '('
 438                         { $$ = prepend_elem(OP_HSLICE,
 439                                 newOP(OP_PUSHMARK, 0),
 440                                 list(
 441                                     newLISTOP(OP_HSLICE, 0,
 442                                         list($3),
 443                                         ref(oopsHV($1), OP_HSLICE))));
 444                             expect = XOPERATOR; }
 445         |       DELETE scalar '{' expr ';' '}'  %prec '('
 446                         { $$ = newBINOP(OP_DELETE, 0, oopsHV($2), jmaybe($4));
 447                             expect = XOPERATOR; }
 448         |       DELETE '(' scalar '{' expr ';' '}' ')'  %prec '('
 449                         { $$ = newBINOP(OP_DELETE, 0, oopsHV($3), jmaybe($5));
 450                             expect = XOPERATOR; }
 451         |       THING   %prec '('
 452                         { $$ = $1; }
 453         |       amper
 454                         { $$ = newUNOP(OP_ENTERSUBR, 0,
 455                                 scalar($1)); }
 456         |       amper '(' ')'
 457                         { $$ = newUNOP(OP_ENTERSUBR, OPf_STACKED, scalar($1)); }
 458         |       amper '(' expr crp
 459                         { $$ = newUNOP(OP_ENTERSUBR, OPf_STACKED,
 460                             list(prepend_elem(OP_LIST, scalar($1), $3))); }
 461         |       DO sexpr        %prec UNIOP
 462                         { $$ = newUNOP(OP_DOFILE, 0, scalar($2));
 463                           allgvs = TRUE;}
 464         |       DO block        %prec '('
 465                         { $$ = newUNOP(OP_NULL, OPf_SPECIAL, scope($2)); }
 466         |       DO WORD '(' ')'
 467                         { $$ = newUNOP(OP_ENTERSUBR, OPf_SPECIAL|OPf_STACKED,
 468                             list(prepend_elem(OP_LIST,
 469                                 scalar(newCVREF(scalar($2))), newNULLLIST()))); }
 470         |       DO WORD '(' expr crp
 471                         { $$ = newUNOP(OP_ENTERSUBR, OPf_SPECIAL|OPf_STACKED,
 472                             list(prepend_elem(OP_LIST,
 473                                 scalar(newCVREF(scalar($2))),
 474                                 $4))); }
 475         |       DO scalar '(' ')'
 476                         { $$ = newUNOP(OP_ENTERSUBR, OPf_SPECIAL|OPf_STACKED,
 477                             list(prepend_elem(OP_LIST,
 478                                 scalar(newCVREF(scalar($2))), newNULLLIST())));}
 479         |       DO scalar '(' expr crp
 480                         { $$ = newUNOP(OP_ENTERSUBR, OPf_SPECIAL|OPf_STACKED,
 481                             list(prepend_elem(OP_LIST,
 482                                 scalar(newCVREF(scalar($2))),
 483                                 $4))); }
 484         |       LOOPEX
 485                         { $$ = newOP($1, OPf_SPECIAL); }
 486         |       LOOPEX WORD
 487                         { $$ = newPVOP($1, 0,
 488                                 savestr(SvPVnx(((SVOP*)$2)->op_sv)));
 489                             op_free($2); }
 490         |       UNIOP
 491                         { $$ = newOP($1, 0); }
 492         |       UNIOP block
 493                         { $$ = newUNOP($1, 0, $2); }
 494         |       UNIOP sexpr
 495                         { $$ = newUNOP($1, 0, $2); }
 496         |       FUNC0
 497                         { $$ = newOP($1, 0); }
 498         |       FUNC0 '(' ')'
 499                         { $$ = newOP($1, 0); }
 500         |       FUNC1 '(' ')'
 501                         { $$ = newOP($1, OPf_SPECIAL); }
 502         |       FUNC1 '(' expr ')'
 503                         { $$ = newUNOP($1, 0, $3); }
 504         |       PMFUNC '(' sexpr ')'
 505                         { $$ = pmruntime($1, $3, Nullop); }
 506         |       PMFUNC '(' sexpr ',' sexpr ')'
 507                         { $$ = pmruntime($1, $3, $5); }
 508         |       WORD
 509         |       listop
 510         ;
 511
 512 listexpr:       /* NULL */
 513                         { $$ = newNULLLIST(); }
 514         |       expr
 515                         { $$ = $1; }
 516         ;
 517
 518 amper   :       '&' indirob
 519                         { $$ = newCVREF($2); }
 520         ;
 521
 522 scalar  :       '$' indirob
 523                         { $$ = newSVREF($2); }
 524         ;
 525
 526 ary     :       '@' indirob
 527                         { $$ = newAVREF($2); }
 528         ;
 529
 530 hsh     :       '%' indirob
 531                         { $$ = newHVREF($2); }
 532         ;
 533
 534 arylen  :       DOLSHARP indirob
 535                         { $$ = newAVREF($2); }
 536         ;
 537
 538 star    :       '*' indirob
 539                         { $$ = newGVREF($2); }
 540         ;
 541
 542 indirob :       WORD
 543                         { $$ = scalar($1); }
 544         |       scalar
 545                         { $$ = scalar($1); }
 546         |       block
 547                         { $$ = scalar(scope($1)); }
 548
 549         ;
 550
 551 crp     :       ',' ')'
 552                         { $$ = 1; }
 553         |       ')'
 554                         { $$ = 0; }
 555         ;
 556
 557 crb     :       ',' ']'
 558                         { $$ = 1; }
 559         |       ']'
 560                         { $$ = 0; }
 561         ;
 562
 563 crhb    :       ',' ';' '}'
 564                         { $$ = 1; }
 565         |       ';' '}'
 566                         { $$ = 0; }
 567         ;
 568
 569 %% /* PROGRAM */