perly.y

   1 /*    perly.y
   2  *
   3  *    Copyright (c) 1991-2001, 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  */
   9
  10 /*
  11  * 'I see,' laughed Strider.  'I look foul and feel fair.  Is that it?
  12  * All that is gold does not glitter, not all those who wander are lost.'
  13  */
  14
  15 %{
  16 #include "EXTERN.h"
  17 #define PERL_IN_PERLY_C
  18 #include "perl.h"
  19 #ifdef EBCDIC
  20 #undef YYDEBUG
  21 #endif
  22 #define dep() deprecate("\"do\" to call subroutines")
  23
  24 /* stuff included here to make perly_c.diff apply better */
  25
  26 #define yydebug     PL_yydebug
  27 #define yynerrs     PL_yynerrs
  28 #define yyerrflag   PL_yyerrflag
  29 #define yychar      PL_yychar
  30 #define yyval       PL_yyval
  31 #define yylval      PL_yylval
  32
  33 struct ysv {
  34     short* yyss;
  35     YYSTYPE* yyvs;
  36     int oldyydebug;
  37     int oldyynerrs;
  38     int oldyyerrflag;
  39     int oldyychar;
  40     YYSTYPE oldyyval;
  41     YYSTYPE oldyylval;
  42 };
  43
  44 static void yydestruct(pTHXo_ void *ptr);
  45
  46 %}
  47
  48 %start prog
  49
  50 %{
  51 #if 0 /* get this from perly.h instead */
  52 %}
  53
  54 %union {
  55     I32 ival;
  56     char *pval;
  57     OP *opval;
  58     GV *gvval;
  59 }
  60
  61 %{
  62 #endif /* 0 */
  63
  64 #ifdef USE_PURE_BISON
  65 #define YYLEX_PARAM (&yychar)
  66 #define yylex yylex_r
  67 #endif
  68
  69 %}
  70
  71 %token <ival> '{'
  72
  73 %token <opval> WORD METHOD FUNCMETH THING PMFUNC PRIVATEREF
  74 %token <opval> FUNC0SUB UNIOPSUB LSTOPSUB
  75 %token <pval> LABEL
  76 %token <ival> FORMAT SUB ANONSUB PACKAGE USE
  77 %token <ival> WHILE UNTIL IF UNLESS ELSE ELSIF CONTINUE FOR
  78 %token <ival> LOOPEX DOTDOT
  79 %token <ival> FUNC0 FUNC1 FUNC UNIOP LSTOP
  80 %token <ival> RELOP EQOP MULOP ADDOP
  81 %token <ival> DOLSHARP DO HASHBRACK NOAMP
  82 %token <ival> LOCAL MY MYSUB
  83 %token COLONATTR
  84
  85 %type <ival> prog decl format startsub startanonsub startformsub
  86 %type <ival> remember mremember '&'
  87 %type <opval> block mblock lineseq line loop cond else
  88 %type <opval> expr term subscripted scalar ary hsh arylen star amper sideff
  89 %type <opval> argexpr nexpr texpr iexpr mexpr mnexpr mtexpr miexpr
  90 %type <opval> listexpr listexprcom indirob listop method
  91 %type <opval> formname subname proto subbody cont my_scalar
  92 %type <opval> subattrlist myattrlist mysubrout myattrterm myterm
  93 %type <opval> termbinop termunop anonymous termdo
  94 %type <pval> label
  95
  96 %nonassoc PREC_LOW
  97 %nonassoc LOOPEX
  98
  99 %left <ival> OROP
 100 %left ANDOP
 101 %right NOTOP
 102 %nonassoc LSTOP LSTOPSUB
 103 %left ','
 104 %right <ival> ASSIGNOP
 105 %right '?' ':'
 106 %nonassoc DOTDOT
 107 %left OROR
 108 %left ANDAND
 109 %left <ival> BITOROP
 110 %left <ival> BITANDOP
 111 %nonassoc EQOP
 112 %nonassoc RELOP
 113 %nonassoc UNIOP UNIOPSUB
 114 %left <ival> SHIFTOP
 115 %left ADDOP
 116 %left MULOP
 117 %left <ival> MATCHOP
 118 %right '!' '~' UMINUS REFGEN
 119 %right <ival> POWOP
 120 %nonassoc PREINC PREDEC POSTINC POSTDEC
 121 %left ARROW
 122 %nonassoc <ival> ')'
 123 %left '('
 124 %left '[' '{'
 125
 126 %% /* RULES */
 127
 128 /* The whole program */
 129 prog    :       /* NULL */
 130                 {
 131 #if defined(YYDEBUG) && defined(DEBUGGING)
 132                     yydebug = (DEBUG_p_TEST);
 133 #endif
 134                     PL_expect = XSTATE; $$ = block_start(TRUE);
 135                 }
 136         /*CONTINUED*/   lineseq
 137                         { newPROG(block_end($1,$2)); }
 138         ;
 139
 140 /* An ordinary block */
 141 block   :       '{' remember lineseq '}'
 142                         { if (PL_copline > (line_t)$1)
 143                               PL_copline = $1;
 144                           $$ = block_end($2, $3); }
 145         ;
 146
 147 remember:       /* NULL */      /* start a full lexical scope */
 148                         { $$ = block_start(TRUE); }
 149         ;
 150
 151 mblock  :       '{' mremember lineseq '}'
 152                         { if (PL_copline > (line_t)$1)
 153                               PL_copline = $1;
 154                           $$ = block_end($2, $3); }
 155         ;
 156
 157 mremember:      /* NULL */      /* start a partial lexical scope */
 158                         { $$ = block_start(FALSE); }
 159         ;
 160
 161 /* A collection of "lines" in the program */
 162 lineseq :       /* NULL */
 163                         { $$ = Nullop; }
 164         |       lineseq decl
 165                         { $$ = $1; }
 166         |       lineseq line
 167                         {   $$ = append_list(OP_LINESEQ,
 168                                 (LISTOP*)$1, (LISTOP*)$2);
 169                             PL_pad_reset_pending = TRUE;
 170                             if ($1 && $2) PL_hints |= HINT_BLOCK_SCOPE; }
 171         ;
 172
 173 /* A "line" in the program */
 174 line    :       label cond
 175                         { $$ = newSTATEOP(0, $1, $2); }
 176         |       loop    /* loops add their own labels */
 177         |       label ';'
 178                         { if ($1 != Nullch) {
 179                               $$ = newSTATEOP(0, $1, newOP(OP_NULL, 0));
 180                             }
 181                             else {
 182                               $$ = Nullop;
 183                               PL_copline = NOLINE;
 184                             }
 185                             PL_expect = XSTATE; }
 186         |       label sideff ';'
 187                         { $$ = newSTATEOP(0, $1, $2);
 188                           PL_expect = XSTATE; }
 189         ;
 190
 191 /* An expression which may have a side-effect */
 192 sideff  :       error
 193                         { $$ = Nullop; }
 194         |       expr
 195                         { $$ = $1; }
 196         |       expr IF expr
 197                         { $$ = newLOGOP(OP_AND, 0, $3, $1); }
 198         |       expr UNLESS expr
 199                         { $$ = newLOGOP(OP_OR, 0, $3, $1); }
 200         |       expr WHILE expr
 201                         { $$ = newLOOPOP(OPf_PARENS, 1, scalar($3), $1); }
 202         |       expr UNTIL iexpr
 203                         { $$ = newLOOPOP(OPf_PARENS, 1, $3, $1);}
 204         |       expr FOR expr
 205                         { $$ = newFOROP(0, Nullch, $2,
 206                                         Nullop, $3, $1, Nullop); }
 207         ;
 208
 209 /* else and elsif blocks */
 210 else    :       /* NULL */
 211                         { $$ = Nullop; }
 212         |       ELSE mblock
 213                         { ($2)->op_flags |= OPf_PARENS; $$ = scope($2); }
 214         |       ELSIF '(' mexpr ')' mblock else
 215                         { PL_copline = $1;
 216                             $$ = newCONDOP(0, $3, scope($5), $6);
 217                             PL_hints |= HINT_BLOCK_SCOPE; }
 218         ;
 219
 220 /* Real conditional expressions */
 221 cond    :       IF '(' remember mexpr ')' mblock else
 222                         { PL_copline = $1;
 223                             $$ = block_end($3,
 224                                    newCONDOP(0, $4, scope($6), $7)); }
 225         |       UNLESS '(' remember miexpr ')' mblock else
 226                         { PL_copline = $1;
 227                             $$ = block_end($3,
 228                                    newCONDOP(0, $4, scope($6), $7)); }
 229         ;
 230
 231 /* Continue blocks */
 232 cont    :       /* NULL */
 233                         { $$ = Nullop; }
 234         |       CONTINUE block
 235                         { $$ = scope($2); }
 236         ;
 237
 238 /* Loops: while, until, for, and a bare block */
 239 loop    :       label WHILE '(' remember mtexpr ')' mblock cont
 240                         { PL_copline = $2;
 241                             $$ = block_end($4,
 242                                    newSTATEOP(0, $1,
 243                                      newWHILEOP(0, 1, (LOOP*)Nullop,
 244                                                 $2, $5, $7, $8))); }
 245         |       label UNTIL '(' remember miexpr ')' mblock cont
 246                         { PL_copline = $2;
 247                             $$ = block_end($4,
 248                                    newSTATEOP(0, $1,
 249                                      newWHILEOP(0, 1, (LOOP*)Nullop,
 250                                                 $2, $5, $7, $8))); }
 251         |       label FOR MY remember my_scalar '(' mexpr ')' mblock cont
 252                         { $$ = block_end($4,
 253                                  newFOROP(0, $1, $2, $5, $7, $9, $10)); }
 254         |       label FOR scalar '(' remember mexpr ')' mblock cont
 255                         { $$ = block_end($5,
 256                                  newFOROP(0, $1, $2, mod($3, OP_ENTERLOOP),
 257                                           $6, $8, $9)); }
 258         |       label FOR '(' remember mexpr ')' mblock cont
 259                         { $$ = block_end($4,
 260                                  newFOROP(0, $1, $2, Nullop, $5, $7, $8)); }
 261         |       label FOR '(' remember mnexpr ';' mtexpr ';' mnexpr ')' mblock
 262                         /* basically fake up an initialize-while lineseq */
 263                         { OP *forop;
 264                           PL_copline = $2;
 265                           forop = newSTATEOP(0, $1,
 266                                             newWHILEOP(0, 1, (LOOP*)Nullop,
 267                                                 $2, scalar($7),
 268                                                 $11, $9));
 269                           if ($5) {
 270                                 forop = append_elem(OP_LINESEQ,
 271                                         newSTATEOP(0, ($1?savepv($1):Nullch),
 272                                                    $5),
 273                                         forop);
 274                           }
 275
 276                           $$ = block_end($4, forop); }
 277         |       label block cont  /* a block is a loop that happens once */
 278                         { $$ = newSTATEOP(0, $1,
 279                                  newWHILEOP(0, 1, (LOOP*)Nullop,
 280                                             NOLINE, Nullop, $2, $3)); }
 281         ;
 282
 283 /* Normal expression */
 284 nexpr   :       /* NULL */
 285                         { $$ = Nullop; }
 286         |       sideff
 287         ;
 288
 289 /* Boolean expression */
 290 texpr   :       /* NULL means true */
 291                         { (void)scan_num("1", &yylval); $$ = yylval.opval; }
 292         |       expr
 293         ;
 294
 295 /* Inverted boolean expression */
 296 iexpr   :       expr
 297                         { $$ = invert(scalar($1)); }
 298         ;
 299
 300 /* Expression with its own lexical scope */
 301 mexpr   :       expr
 302                         { $$ = $1; intro_my(); }
 303         ;
 304
 305 mnexpr  :       nexpr
 306                         { $$ = $1; intro_my(); }
 307         ;
 308
 309 mtexpr  :       texpr
 310                         { $$ = $1; intro_my(); }
 311         ;
 312
 313 miexpr  :       iexpr
 314                         { $$ = $1; intro_my(); }
 315         ;
 316
 317 /* Optional "MAIN:"-style loop labels */
 318 label   :       /* empty */
 319                         { $$ = Nullch; }
 320         |       LABEL
 321         ;
 322
 323 /* Some kind of declaration - does not take part in the parse tree */
 324 decl    :       format
 325                         { $$ = 0; }
 326         |       subrout
 327                         { $$ = 0; }
 328         |       mysubrout
 329                         { $$ = 0; }
 330         |       package
 331                         { $$ = 0; }
 332         |       use
 333                         { $$ = 0; }
 334         ;
 335
 336 format  :       FORMAT startformsub formname block
 337                         { newFORM($2, $3, $4); }
 338         ;
 339
 340 formname:       WORD            { $$ = $1; }
 341         |       /* NULL */      { $$ = Nullop; }
 342         ;
 343
 344 /* Unimplemented "my sub foo { }" */
 345 mysubrout:      MYSUB startsub subname proto subattrlist subbody
 346                         { newMYSUB($2, $3, $4, $5, $6); }
 347         ;
 348
 349 /* Subroutine definition */
 350 subrout :       SUB startsub subname proto subattrlist subbody
 351                         { newATTRSUB($2, $3, $4, $5, $6); }
 352         ;
 353
 354 startsub:       /* NULL */      /* start a regular subroutine scope */
 355                         { $$ = start_subparse(FALSE, 0); }
 356         ;
 357
 358 startanonsub:   /* NULL */      /* start an anonymous subroutine scope */
 359                         { $$ = start_subparse(FALSE, CVf_ANON); }
 360         ;
 361
 362 startformsub:   /* NULL */      /* start a format subroutine scope */
 363                         { $$ = start_subparse(TRUE, 0); }
 364         ;
 365
 366 /* Name of a subroutine - must be a bareword, could be special */
 367 subname :       WORD    { STRLEN n_a; char *name = SvPV(((SVOP*)$1)->op_sv,n_a);
 368                           if (strEQ(name, "BEGIN") || strEQ(name, "END")
 369                               || strEQ(name, "INIT") || strEQ(name, "CHECK"))
 370                               CvSPECIAL_on(PL_compcv);
 371                           $$ = $1; }
 372         ;
 373
 374 /* Subroutine prototype */
 375 proto   :       /* NULL */
 376                         { $$ = Nullop; }
 377         |       THING
 378         ;
 379
 380 /* Optional list of subroutine attributes */
 381 subattrlist:    /* NULL */
 382                         { $$ = Nullop; }
 383         |       COLONATTR THING
 384                         { $$ = $2; }
 385         |       COLONATTR
 386                         { $$ = Nullop; }
 387         ;
 388
 389 /* List of attributes for a "my" variable declaration */
 390 myattrlist:     COLONATTR THING
 391                         { $$ = $2; }
 392         |       COLONATTR
 393                         { $$ = Nullop; }
 394         ;
 395
 396 /* Subroutine body - either null or a block */
 397 subbody :       block   { $$ = $1; }
 398         |       ';'     { $$ = Nullop; PL_expect = XSTATE; }
 399         ;
 400
 401 package :       PACKAGE WORD ';'
 402                         { package($2); }
 403         |       PACKAGE ';'
 404                         { package(Nullop); }
 405         ;
 406
 407 use     :       USE startsub
 408                         { CvSPECIAL_on(PL_compcv); /* It's a BEGIN {} */ }
 409                     WORD WORD listexpr ';'
 410                         { utilize($1, $2, $4, $5, $6); }
 411         ;
 412
 413 /* Ordinary expressions; logical combinations */
 414 expr    :       expr ANDOP expr
 415                         { $$ = newLOGOP(OP_AND, 0, $1, $3); }
 416         |       expr OROP expr
 417                         { $$ = newLOGOP($2, 0, $1, $3); }
 418         |       argexpr %prec PREC_LOW
 419         ;
 420
 421 /* Expressions are a list of terms joined by commas */
 422 argexpr :       argexpr ','
 423                         { $$ = $1; }
 424         |       argexpr ',' term
 425                         { $$ = append_elem(OP_LIST, $1, $3); }
 426         |       term %prec PREC_LOW
 427         ;
 428
 429 /* List operators */
 430 listop  :       LSTOP indirob argexpr          /* print $fh @args */
 431                         { $$ = convert($1, OPf_STACKED,
 432                                 prepend_elem(OP_LIST, newGVREF($1,$2), $3) ); }
 433         |       FUNC '(' indirob expr ')'      /* print ($fh @args */
 434                         { $$ = convert($1, OPf_STACKED,
 435                                 prepend_elem(OP_LIST, newGVREF($1,$3), $4) ); }
 436         |       term ARROW method '(' listexprcom ')' /* $foo->bar(list) */
 437                         { $$ = convert(OP_ENTERSUB, OPf_STACKED,
 438                                 append_elem(OP_LIST,
 439                                     prepend_elem(OP_LIST, scalar($1), $5),
 440                                     newUNOP(OP_METHOD, 0, $3))); }
 441         |       term ARROW method                     /* $foo->bar */
 442                         { $$ = convert(OP_ENTERSUB, OPf_STACKED,
 443                                 append_elem(OP_LIST, scalar($1),
 444                                     newUNOP(OP_METHOD, 0, $3))); }
 445         |       METHOD indirob listexpr              /* new Class @args */
 446                         { $$ = convert(OP_ENTERSUB, OPf_STACKED,
 447                                 append_elem(OP_LIST,
 448                                     prepend_elem(OP_LIST, $2, $3),
 449                                     newUNOP(OP_METHOD, 0, $1))); }
 450         |       FUNCMETH indirob '(' listexprcom ')' /* method $object (@args) */
 451                         { $$ = convert(OP_ENTERSUB, OPf_STACKED,
 452                                 append_elem(OP_LIST,
 453                                     prepend_elem(OP_LIST, $2, $4),
 454                                     newUNOP(OP_METHOD, 0, $1))); }
 455         |       LSTOP listexpr                       /* print @args */
 456                         { $$ = convert($1, 0, $2); }
 457         |       FUNC '(' listexprcom ')'             /* print (@args) */
 458                         { $$ = convert($1, 0, $3); }
 459         |       LSTOPSUB startanonsub block          /* map { foo } ... */
 460                         { $3 = newANONATTRSUB($2, 0, Nullop, $3); }
 461                     listexpr            %prec LSTOP  /* ... @bar */
 462                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 463                                  append_elem(OP_LIST,
 464                                    prepend_elem(OP_LIST, $3, $5), $1)); }
 465         ;
 466
 467 /* Names of methods. May use $object->$methodname */
 468 method  :       METHOD
 469         |       scalar
 470         ;
 471
 472 /* Some kind of subscripted expression */
 473 subscripted:    star '{' expr ';' '}'        /* *main::{something} */
 474                         /* In this and all the hash accessors, ';' is
 475                          * provided by the tokeniser */
 476                         { $$ = newBINOP(OP_GELEM, 0, $1, scalar($3)); }
 477         |       scalar '[' expr ']'          /* $array[$element] */
 478                         { $$ = newBINOP(OP_AELEM, 0, oopsAV($1), scalar($3)); }
 479         |       term ARROW '[' expr ']'      /* somearef->[$element] */
 480                         { $$ = newBINOP(OP_AELEM, 0,
 481                                         ref(newAVREF($1),OP_RV2AV),
 482                                         scalar($4));}
 483         |       subscripted '[' expr ']'    /* $foo->[$bar]->[$baz] */
 484                         { $$ = newBINOP(OP_AELEM, 0,
 485                                         ref(newAVREF($1),OP_RV2AV),
 486                                         scalar($3));}
 487         |       scalar '{' expr ';' '}'    /* $foo->{bar();} */
 488                         { $$ = newBINOP(OP_HELEM, 0, oopsHV($1), jmaybe($3));
 489                             PL_expect = XOPERATOR; }
 490         |       term ARROW '{' expr ';' '}' /* somehref->{bar();} */
 491                         { $$ = newBINOP(OP_HELEM, 0,
 492                                         ref(newHVREF($1),OP_RV2HV),
 493                                         jmaybe($4));
 494                             PL_expect = XOPERATOR; }
 495         |       subscripted '{' expr ';' '}' /* $foo->[bar]->{baz;} */
 496                         { $$ = newBINOP(OP_HELEM, 0,
 497                                         ref(newHVREF($1),OP_RV2HV),
 498                                         jmaybe($3));
 499                             PL_expect = XOPERATOR; }
 500         |       term ARROW '(' ')'          /* $subref->() */
 501                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 502                                    newCVREF(0, scalar($1))); }
 503         |       term ARROW '(' expr ')'     /* $subref->(@args) */
 504                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 505                                    append_elem(OP_LIST, $4,
 506                                        newCVREF(0, scalar($1)))); }
 507
 508         |       subscripted '(' expr ')'   /* $foo->{bar}->(@args) */
 509                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 510                                    append_elem(OP_LIST, $3,
 511                                                newCVREF(0, scalar($1)))); }
 512         |       subscripted '(' ')'        /* $foo->{bar}->() */
 513                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 514                                    newCVREF(0, scalar($1))); }
 515     ;
 516
 517 /* Binary operators between terms */
 518 termbinop       :       term ASSIGNOP term             /* $x = $y */
 519                         { $$ = newASSIGNOP(OPf_STACKED, $1, $2, $3); }
 520         |       term POWOP term                        /* $x ** $y */
 521                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 522         |       term MULOP term                        /* $x * $y, $x x $y */
 523                         {   if ($2 != OP_REPEAT)
 524                                 scalar($1);
 525                             $$ = newBINOP($2, 0, $1, scalar($3)); }
 526         |       term ADDOP term                        /* $x + $y */
 527                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 528         |       term SHIFTOP term                      /* $x >> $y, $x << $y */
 529                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 530         |       term RELOP term                        /* $x > $y, etc. */
 531                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 532         |       term EQOP term                         /* $x == $y, $x eq $y */
 533                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 534         |       term BITANDOP term                     /* $x & $y */
 535                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 536         |       term BITOROP term                      /* $x | $y */
 537                         { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
 538         |       term DOTDOT term                       /* $x..$y, $x...$y */
 539                         { $$ = newRANGE($2, scalar($1), scalar($3));}
 540         |       term ANDAND term                       /* $x && $y */
 541                         { $$ = newLOGOP(OP_AND, 0, $1, $3); }
 542         |       term OROR term                         /* $x || $y */
 543                         { $$ = newLOGOP(OP_OR, 0, $1, $3); }
 544         |       term MATCHOP term                      /* $x =~ /$y/ */
 545                         { $$ = bind_match($2, $1, $3); }
 546     ;
 547
 548 /* Unary operators and terms */
 549 termunop : '-' term %prec UMINUS                       /* -$x */
 550                         { $$ = newUNOP(OP_NEGATE, 0, scalar($2)); }
 551         |       '+' term %prec UMINUS                  /* +$x */
 552                         { $$ = $2; }
 553         |       '!' term                               /* !$x */
 554                         { $$ = newUNOP(OP_NOT, 0, scalar($2)); }
 555         |       '~' term                               /* ~$x */
 556                         { $$ = newUNOP(OP_COMPLEMENT, 0, scalar($2));}
 557         |       term POSTINC                           /* $x++ */
 558                         { $$ = newUNOP(OP_POSTINC, 0,
 559                                         mod(scalar($1), OP_POSTINC)); }
 560         |       term POSTDEC                           /* $x-- */
 561                         { $$ = newUNOP(OP_POSTDEC, 0,
 562                                         mod(scalar($1), OP_POSTDEC)); }
 563         |       PREINC term                            /* ++$x */
 564                         { $$ = newUNOP(OP_PREINC, 0,
 565                                         mod(scalar($2), OP_PREINC)); }
 566         |       PREDEC term                            /* --$x */
 567                         { $$ = newUNOP(OP_PREDEC, 0,
 568                                         mod(scalar($2), OP_PREDEC)); }
 569
 570     ;
 571
 572 /* Constructors for anonymous data */
 573 anonymous:      '[' expr ']'
 574                         { $$ = newANONLIST($2); }
 575         |       '[' ']'
 576                         { $$ = newANONLIST(Nullop); }
 577         |       HASHBRACK expr ';' '}'  %prec '(' /* { foo => "Bar" } */
 578                         { $$ = newANONHASH($2); }
 579         |       HASHBRACK ';' '}'       %prec '(' /* { } (';' by tokener) */
 580                         { $$ = newANONHASH(Nullop); }
 581         |       ANONSUB startanonsub proto subattrlist block    %prec '('
 582                         { $$ = newANONATTRSUB($2, $3, $4, $5); }
 583
 584     ;
 585
 586 /* Things called with "do" */
 587 termdo  :       DO term %prec UNIOP                     /* do $filename */
 588                         { $$ = dofile($2); }
 589         |       DO block        %prec '('               /* do { code */
 590                         { $$ = newUNOP(OP_NULL, OPf_SPECIAL, scope($2)); }
 591         |       DO WORD '(' ')'                         /* do somesub() */
 592                         { $$ = newUNOP(OP_ENTERSUB,
 593                             OPf_SPECIAL|OPf_STACKED,
 594                             prepend_elem(OP_LIST,
 595                                 scalar(newCVREF(
 596                                     (OPpENTERSUB_AMPER<<8),
 597                                     scalar($2)
 598                                 )),Nullop)); dep();}
 599         |       DO WORD '(' expr ')'                    /* do somesub(@args) */
 600                         { $$ = newUNOP(OP_ENTERSUB,
 601                             OPf_SPECIAL|OPf_STACKED,
 602                             append_elem(OP_LIST,
 603                                 $4,
 604                                 scalar(newCVREF(
 605                                     (OPpENTERSUB_AMPER<<8),
 606                                     scalar($2)
 607                                 )))); dep();}
 608         |       DO scalar '(' ')'                      /* do $subref () */
 609                         { $$ = newUNOP(OP_ENTERSUB, OPf_SPECIAL|OPf_STACKED,
 610                             prepend_elem(OP_LIST,
 611                                 scalar(newCVREF(0,scalar($2))), Nullop)); dep();}
 612         |       DO scalar '(' expr ')'                 /* do $subref (@args) */
 613                         { $$ = newUNOP(OP_ENTERSUB, OPf_SPECIAL|OPf_STACKED,
 614                             prepend_elem(OP_LIST,
 615                                 $4,
 616                                 scalar(newCVREF(0,scalar($2))))); dep();}
 617
 618         ;
 619
 620 term    :       termbinop
 621         |       termunop
 622         |       anonymous
 623         |       termdo
 624         |       term '?' term ':' term
 625                         { $$ = newCONDOP(0, $1, $3, $5); }
 626         |       REFGEN term                          /* \$x, \@y, \%z */
 627                         { $$ = newUNOP(OP_REFGEN, 0, mod($2,OP_REFGEN)); }
 628         |       myattrterm      %prec UNIOP
 629                         { $$ = $1; }
 630         |       LOCAL term      %prec UNIOP
 631                         { $$ = localize($2,$1); }
 632         |       '(' expr ')'
 633                         { $$ = sawparens($2); }
 634         |       '(' ')'
 635                         { $$ = sawparens(newNULLLIST()); }
 636         |       scalar  %prec '('
 637                         { $$ = $1; }
 638         |       star    %prec '('
 639                         { $$ = $1; }
 640         |       hsh     %prec '('
 641                         { $$ = $1; }
 642         |       ary     %prec '('
 643                         { $$ = $1; }
 644         |       arylen  %prec '('                    /* $#x, $#{ something } */
 645                         { $$ = newUNOP(OP_AV2ARYLEN, 0, ref($1, OP_AV2ARYLEN));}
 646         |       subscripted
 647                         { $$ = $1; }
 648         |       '(' expr ')' '[' expr ']'            /* list slice */
 649                         { $$ = newSLICEOP(0, $5, $2); }
 650         |       '(' ')' '[' expr ']'                 /* empty list slice! */
 651                         { $$ = newSLICEOP(0, $4, Nullop); }
 652         |       ary '[' expr ']'                     /* array slice */
 653                         { $$ = prepend_elem(OP_ASLICE,
 654                                 newOP(OP_PUSHMARK, 0),
 655                                     newLISTOP(OP_ASLICE, 0,
 656                                         list($3),
 657                                         ref($1, OP_ASLICE))); }
 658         |       ary '{' expr ';' '}'                 /* @hash{@keys} */
 659                         { $$ = prepend_elem(OP_HSLICE,
 660                                 newOP(OP_PUSHMARK, 0),
 661                                     newLISTOP(OP_HSLICE, 0,
 662                                         list($3),
 663                                         ref(oopsHV($1), OP_HSLICE)));
 664                             PL_expect = XOPERATOR; }
 665         |       THING   %prec '('
 666                         { $$ = $1; }
 667         |       amper                                /* &foo; */
 668                         { $$ = newUNOP(OP_ENTERSUB, 0, scalar($1)); }
 669         |       amper '(' ')'                        /* &foo() */
 670                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, scalar($1)); }
 671         |       amper '(' expr ')'                   /* &foo(@args) */
 672                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 673                             append_elem(OP_LIST, $3, scalar($1))); }
 674         |       NOAMP WORD listexpr                  /* foo(@args) */
 675                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 676                             append_elem(OP_LIST, $3, scalar($2))); }
 677         |       LOOPEX  /* loop exiting command (goto, last, dump, etc) */
 678                         { $$ = newOP($1, OPf_SPECIAL);
 679                             PL_hints |= HINT_BLOCK_SCOPE; }
 680         |       LOOPEX term
 681                         { $$ = newLOOPEX($1,$2); }
 682         |       NOTOP argexpr                        /* not $foo */
 683                         { $$ = newUNOP(OP_NOT, 0, scalar($2)); }
 684         |       UNIOP                                /* Unary op, $_ implied */
 685                         { $$ = newOP($1, 0); }
 686         |       UNIOP block                          /* eval { foo }, I *think* */
 687                         { $$ = newUNOP($1, 0, $2); }
 688         |       UNIOP term                           /* Unary op */
 689                         { $$ = newUNOP($1, 0, $2); }
 690         |       UNIOPSUB term                        /* Sub treated as unop */
 691                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 692                             append_elem(OP_LIST, $2, scalar($1))); }
 693         |       FUNC0                                /* Nullary operator */
 694                         { $$ = newOP($1, 0); }
 695         |       FUNC0 '(' ')'
 696                         { $$ = newOP($1, 0); }
 697         |       FUNC0SUB                             /* Sub treated as nullop */
 698                         { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
 699                                 scalar($1)); }
 700         |       FUNC1 '(' ')'                        /* not () */
 701                         { $$ = newOP($1, OPf_SPECIAL); }
 702         |       FUNC1 '(' expr ')'                   /* not($foo) */
 703                         { $$ = newUNOP($1, 0, $3); }
 704         |       PMFUNC '(' term ')'                  /* split (/foo/) */
 705                         { $$ = pmruntime($1, $3, Nullop); }
 706         |       PMFUNC '(' term ',' term ')'         /* split (/foo/,$bar) */
 707                         { $$ = pmruntime($1, $3, $5); }
 708         |       WORD
 709         |       listop
 710         ;
 711
 712 /* "my" declarations, with optional attributes */
 713 myattrterm:     MY myterm myattrlist
 714                         { $$ = my_attrs($2,$3); }
 715         |       MY myterm
 716                         { $$ = localize($2,$1); }
 717         ;
 718
 719 /* Things that can be "my"'d */
 720 myterm  :       '(' expr ')'
 721                         { $$ = sawparens($2); }
 722         |       '(' ')'
 723                         { $$ = sawparens(newNULLLIST()); }
 724         |       scalar  %prec '('
 725                         { $$ = $1; }
 726         |       hsh     %prec '('
 727                         { $$ = $1; }
 728         |       ary     %prec '('
 729                         { $$ = $1; }
 730         ;
 731
 732 /* Basic list expressions */
 733 listexpr:       /* NULL */ %prec PREC_LOW
 734                         { $$ = Nullop; }
 735         |       argexpr    %prec PREC_LOW
 736                         { $$ = $1; }
 737         ;
 738
 739 listexprcom:    /* NULL */
 740                         { $$ = Nullop; }
 741         |       expr
 742                         { $$ = $1; }
 743         |       expr ','
 744                         { $$ = $1; }
 745         ;
 746
 747 /* A little bit of trickery to make "for my $foo (@bar)" actually be
 748    lexical */
 749 my_scalar:      scalar
 750                         { PL_in_my = 0; $$ = my($1); }
 751         ;
 752
 753 amper   :       '&' indirob
 754                         { $$ = newCVREF($1,$2); }
 755         ;
 756
 757 scalar  :       '$' indirob
 758                         { $$ = newSVREF($2); }
 759         ;
 760
 761 ary     :       '@' indirob
 762                         { $$ = newAVREF($2); }
 763         ;
 764
 765 hsh     :       '%' indirob
 766                         { $$ = newHVREF($2); }
 767         ;
 768
 769 arylen  :       DOLSHARP indirob
 770                         { $$ = newAVREF($2); }
 771         ;
 772
 773 star    :       '*' indirob
 774                         { $$ = newGVREF(0,$2); }
 775         ;
 776
 777 /* Indirect objects */
 778 indirob :       WORD
 779                         { $$ = scalar($1); }
 780         |       scalar %prec PREC_LOW
 781                         { $$ = scalar($1);  }
 782         |       block
 783                         { $$ = scope($1); }
 784
 785         |       PRIVATEREF
 786                         { $$ = $1; }
 787         ;
 788
 789 %% /* PROGRAM */
 790
 791 /* more stuff added to make perly_c.diff easier to apply */
 792
 793 #ifdef yyparse
 794 #undef yyparse
 795 #endif
 796 #define yyparse() Perl_yyparse(pTHX)
 797