/* perly.y * * Copyright (c) 1991-2002, 2003, 2004, 2005, 2006 Larry Wall * Copyright (c) 2007, 2008, 2009, 2010, 2011 by Larry Wall and others * * You may distribute under the terms of either the GNU General Public * License or the Artistic License, as specified in the README file. * */ /* * 'I see,' laughed Strider. 'I look foul and feel fair. Is that it? * All that is gold does not glitter, not all those who wander are lost.' * * [p.171 of _The Lord of the Rings_, I/x: "Strider"] */ /* * This file holds the grammar for the Perl language. If edited, you need * to run regen_perly.pl, which re-creates the files perly.h, perly.tab * and perly.act which are derived from this. * * The main job of this grammar is to call the various newFOO() * functions in op.c to build a syntax tree of OP structs. * It relies on the lexer in toke.c to do the tokenizing. * * Note: due to the way that the cleanup code works WRT to freeing ops on * the parse stack, it is dangerous to assign to the $n variables within * an action. */ /* Make the parser re-entrant. */ %define api.pure %start grammar %union { I32 ival; /* __DEFAULT__ (marker for regen_perly.pl; must always be 1st union member) */ char *pval; OP *opval; GV *gvval; } %token GRAMPROG GRAMEXPR GRAMBLOCK GRAMBARESTMT GRAMFULLSTMT GRAMSTMTSEQ GRAMSUBSIGNATURE %token '{' '}' '[' ']' '-' '+' '@' '%' '&' '=' '.' %token BAREWORD METHOD FUNCMETH THING PMFUNC PRIVATEREF QWLIST %token FUNC0OP FUNC0SUB UNIOPSUB LSTOPSUB %token PLUGEXPR PLUGSTMT %token LABEL %token FORMAT SUB SIGSUB ANONSUB ANON_SIGSUB PACKAGE USE %token WHILE UNTIL IF UNLESS ELSE ELSIF CONTINUE FOR %token GIVEN WHEN DEFAULT %token LOOPEX DOTDOT YADAYADA %token FUNC0 FUNC1 FUNC UNIOP LSTOP %token MULOP ADDOP %token DOLSHARP DO HASHBRACK NOAMP %token LOCAL MY REQUIRE %token COLONATTR FORMLBRACK FORMRBRACK %token SUBLEXSTART SUBLEXEND %type grammar remember mremember %type startsub startanonsub startformsub %type mintro %type stmtseq fullstmt labfullstmt barestmt block mblock else %type expr term subscripted scalar ary hsh arylen star amper sideff %type sliceme kvslice gelem %type listexpr nexpr texpr iexpr mexpr mnexpr %type optlistexpr optexpr optrepl indirob listop method %type formname subname proto cont my_scalar my_var %type refgen_topic formblock %type subattrlist myattrlist myattrterm myterm %type termbinop termunop anonymous termdo %type termrelop relopchain termeqop eqopchain %type sigslurpsigil %type sigvarname sigdefault sigscalarelem sigslurpelem %type sigelem siglist siglistornull subsigguts subsignature optsubsignature %type subbody optsubbody sigsubbody optsigsubbody %type formstmtseq formline formarg %nonassoc PREC_LOW %nonassoc LOOPEX %left OROP DOROP %left ANDOP %right NOTOP %nonassoc LSTOP LSTOPSUB %left ',' %right ASSIGNOP %right '?' ':' %nonassoc DOTDOT %left OROR DORDOR %left ANDAND %left BITOROP %left BITANDOP %left CHEQOP NCEQOP %left CHRELOP NCRELOP %nonassoc UNIOP UNIOPSUB %nonassoc REQUIRE %left SHIFTOP %left ADDOP %left MULOP %left MATCHOP %right '!' '~' UMINUS REFGEN %right POWOP %nonassoc PREINC PREDEC POSTINC POSTDEC POSTJOIN %left ARROW %nonassoc ')' %left '(' %left '[' '{' %% /* RULES */ /* Top-level choice of what kind of thing yyparse was called to parse */ grammar : GRAMPROG { parser->expect = XSTATE; $$ = 0; } remember stmtseq { newPROG(block_end($3,$4)); PL_compiling.cop_seq = 0; $$ = 0; } | GRAMEXPR { parser->expect = XTERM; $$ = 0; } optexpr { PL_eval_root = $3; $$ = 0; } | GRAMBLOCK { parser->expect = XBLOCK; $$ = 0; } block { PL_pad_reset_pending = TRUE; PL_eval_root = $3; $$ = 0; yyunlex(); parser->yychar = yytoken = YYEOF; } | GRAMBARESTMT { parser->expect = XSTATE; $$ = 0; } barestmt { PL_pad_reset_pending = TRUE; PL_eval_root = $3; $$ = 0; yyunlex(); parser->yychar = yytoken = YYEOF; } | GRAMFULLSTMT { parser->expect = XSTATE; $$ = 0; } fullstmt { PL_pad_reset_pending = TRUE; PL_eval_root = $3; $$ = 0; yyunlex(); parser->yychar = yytoken = YYEOF; } | GRAMSTMTSEQ { parser->expect = XSTATE; $$ = 0; } stmtseq { PL_eval_root = $3; $$ = 0; } | GRAMSUBSIGNATURE { parser->expect = XSTATE; $$ = 0; } subsigguts { PL_eval_root = $3; $$ = 0; } ; /* An ordinary block */ block : '{' remember stmtseq '}' { if (parser->copline > (line_t)$1) parser->copline = (line_t)$1; $$ = block_end($2, $3); } ; /* format body */ formblock: '=' remember ';' FORMRBRACK formstmtseq ';' '.' { if (parser->copline > (line_t)$1) parser->copline = (line_t)$1; $$ = block_end($2, $5); } ; remember: /* NULL */ /* start a full lexical scope */ { $$ = block_start(TRUE); parser->parsed_sub = 0; } ; mblock : '{' mremember stmtseq '}' { if (parser->copline > (line_t)$1) parser->copline = (line_t)$1; $$ = block_end($2, $3); } ; mremember: /* NULL */ /* start a partial lexical scope */ { $$ = block_start(FALSE); parser->parsed_sub = 0; } ; /* A sequence of statements in the program */ stmtseq : /* NULL */ { $$ = NULL; } | stmtseq fullstmt { $$ = op_append_list(OP_LINESEQ, $1, $2); PL_pad_reset_pending = TRUE; if ($1 && $2) PL_hints |= HINT_BLOCK_SCOPE; } ; /* A sequence of format lines */ formstmtseq: /* NULL */ { $$ = NULL; } | formstmtseq formline { $$ = op_append_list(OP_LINESEQ, $1, $2); PL_pad_reset_pending = TRUE; if ($1 && $2) PL_hints |= HINT_BLOCK_SCOPE; } ; /* A statement in the program, including optional labels */ fullstmt: barestmt { $$ = $1 ? newSTATEOP(0, NULL, $1) : NULL; } | labfullstmt { $$ = $1; } ; labfullstmt: LABEL barestmt { SV *label = cSVOPx_sv($1); $$ = newSTATEOP(SvFLAGS(label) & SVf_UTF8, savepv(SvPVX_const(label)), $2); op_free($1); } | LABEL labfullstmt { SV *label = cSVOPx_sv($1); $$ = newSTATEOP(SvFLAGS(label) & SVf_UTF8, savepv(SvPVX_const(label)), $2); op_free($1); } ; /* A bare statement, lacking label and other aspects of state op */ barestmt: PLUGSTMT { $$ = $1; } | FORMAT startformsub formname formblock { CV *fmtcv = PL_compcv; newFORM($2, $3, $4); $$ = NULL; if (CvOUTSIDE(fmtcv) && !CvEVAL(CvOUTSIDE(fmtcv))) { pad_add_weakref(fmtcv); } parser->parsed_sub = 1; } | SUB subname startsub /* sub declaration or definition not within scope of 'use feature "signatures"'*/ { init_named_cv(PL_compcv, $2); parser->in_my = 0; parser->in_my_stash = NULL; } proto subattrlist optsubbody { SvREFCNT_inc_simple_void(PL_compcv); $2->op_type == OP_CONST ? newATTRSUB($3, $2, $5, $6, $7) : newMYSUB($3, $2, $5, $6, $7) ; $$ = NULL; intro_my(); parser->parsed_sub = 1; } | SIGSUB subname startsub /* sub declaration or definition under 'use feature * "signatures"'. (Note that a signature isn't * allowed in a declaration) */ { init_named_cv(PL_compcv, $2); parser->in_my = 0; parser->in_my_stash = NULL; } subattrlist optsigsubbody { SvREFCNT_inc_simple_void(PL_compcv); $2->op_type == OP_CONST ? newATTRSUB($3, $2, NULL, $5, $6) : newMYSUB( $3, $2, NULL, $5, $6) ; $$ = NULL; intro_my(); parser->parsed_sub = 1; } | PACKAGE BAREWORD BAREWORD ';' { package($3); if ($2) package_version($2); $$ = NULL; } | USE startsub { CvSPECIAL_on(PL_compcv); /* It's a BEGIN {} */ } BAREWORD BAREWORD optlistexpr ';' { SvREFCNT_inc_simple_void(PL_compcv); utilize($1, $2, $4, $5, $6); parser->parsed_sub = 1; $$ = NULL; } | IF '(' remember mexpr ')' mblock else { $$ = block_end($3, newCONDOP(0, $4, op_scope($6), $7)); parser->copline = (line_t)$1; } | UNLESS '(' remember mexpr ')' mblock else { $$ = block_end($3, newCONDOP(0, $4, $7, op_scope($6))); parser->copline = (line_t)$1; } | GIVEN '(' remember mexpr ')' mblock { $$ = block_end($3, newGIVENOP($4, op_scope($6), 0)); parser->copline = (line_t)$1; } | WHEN '(' remember mexpr ')' mblock { $$ = block_end($3, newWHENOP($4, op_scope($6))); } | DEFAULT block { $$ = newWHENOP(0, op_scope($2)); } | WHILE '(' remember texpr ')' mintro mblock cont { $$ = block_end($3, newWHILEOP(0, 1, NULL, $4, $7, $8, $6)); parser->copline = (line_t)$1; } | UNTIL '(' remember iexpr ')' mintro mblock cont { $$ = block_end($3, newWHILEOP(0, 1, NULL, $4, $7, $8, $6)); parser->copline = (line_t)$1; } | FOR '(' remember mnexpr ';' { parser->expect = XTERM; } texpr ';' { parser->expect = XTERM; } mintro mnexpr ')' mblock { OP *initop = $4; OP *forop = newWHILEOP(0, 1, NULL, scalar($7), $13, $11, $10); if (initop) { forop = op_prepend_elem(OP_LINESEQ, initop, op_append_elem(OP_LINESEQ, newOP(OP_UNSTACK, OPf_SPECIAL), forop)); } PL_hints |= HINT_BLOCK_SCOPE; $$ = block_end($3, forop); parser->copline = (line_t)$1; } | FOR MY remember my_scalar '(' mexpr ')' mblock cont { $$ = block_end($3, newFOROP(0, $4, $6, $8, $9)); parser->copline = (line_t)$1; } | FOR scalar '(' remember mexpr ')' mblock cont { $$ = block_end($4, newFOROP(0, op_lvalue($2, OP_ENTERLOOP), $5, $7, $8)); parser->copline = (line_t)$1; } | FOR my_refgen remember my_var { parser->in_my = 0; $$ = my($4); } '(' mexpr ')' mblock cont { $$ = block_end( $3, newFOROP(0, op_lvalue( newUNOP(OP_REFGEN, 0, $5), OP_ENTERLOOP), $7, $9, $10) ); parser->copline = (line_t)$1; } | FOR REFGEN refgen_topic '(' remember mexpr ')' mblock cont { $$ = block_end($5, newFOROP( 0, op_lvalue(newUNOP(OP_REFGEN, 0, $3), OP_ENTERLOOP), $6, $8, $9)); parser->copline = (line_t)$1; } | FOR '(' remember mexpr ')' mblock cont { $$ = block_end($3, newFOROP(0, NULL, $4, $6, $7)); parser->copline = (line_t)$1; } | block cont { /* a block is a loop that happens once */ $$ = newWHILEOP(0, 1, NULL, NULL, $1, $2, 0); } | PACKAGE BAREWORD BAREWORD '{' remember { package($3); if ($2) { package_version($2); } } stmtseq '}' { /* a block is a loop that happens once */ $$ = newWHILEOP(0, 1, NULL, NULL, block_end($5, $7), NULL, 0); if (parser->copline > (line_t)$4) parser->copline = (line_t)$4; } | sideff ';' { $$ = $1; } | YADAYADA ';' { $$ = newLISTOP(OP_DIE, 0, newOP(OP_PUSHMARK, 0), newSVOP(OP_CONST, 0, newSVpvs("Unimplemented"))); } | ';' { $$ = NULL; parser->copline = NOLINE; } ; /* Format line */ formline: THING formarg { OP *list; if ($2) { OP *term = $2; list = op_append_elem(OP_LIST, $1, term); } else { list = $1; } if (parser->copline == NOLINE) parser->copline = CopLINE(PL_curcop)-1; else parser->copline--; $$ = newSTATEOP(0, NULL, op_convert_list(OP_FORMLINE, 0, list)); } ; formarg : /* NULL */ { $$ = NULL; } | FORMLBRACK stmtseq FORMRBRACK { $$ = op_unscope($2); } ; /* An expression which may have a side-effect */ sideff : error { $$ = NULL; } | expr { $$ = $1; } | expr IF expr { $$ = newLOGOP(OP_AND, 0, $3, $1); } | expr UNLESS expr { $$ = newLOGOP(OP_OR, 0, $3, $1); } | expr WHILE expr { $$ = newLOOPOP(OPf_PARENS, 1, scalar($3), $1); } | expr UNTIL iexpr { $$ = newLOOPOP(OPf_PARENS, 1, $3, $1); } | expr FOR expr { $$ = newFOROP(0, NULL, $3, $1, NULL); parser->copline = (line_t)$2; } | expr WHEN expr { $$ = newWHENOP($3, op_scope($1)); } ; /* else and elsif blocks */ else : /* NULL */ { $$ = NULL; } | ELSE mblock { ($2)->op_flags |= OPf_PARENS; $$ = op_scope($2); } | ELSIF '(' mexpr ')' mblock else { parser->copline = (line_t)$1; $$ = newCONDOP(0, newSTATEOP(OPf_SPECIAL,NULL,$3), op_scope($5), $6); PL_hints |= HINT_BLOCK_SCOPE; } ; /* Continue blocks */ cont : /* NULL */ { $$ = NULL; } | CONTINUE block { $$ = op_scope($2); } ; /* determine whether there are any new my declarations */ mintro : /* NULL */ { $$ = (PL_min_intro_pending && PL_max_intro_pending >= PL_min_intro_pending); intro_my(); } /* Normal expression */ nexpr : /* NULL */ { $$ = NULL; } | sideff ; /* Boolean expression */ texpr : /* NULL means true */ { YYSTYPE tmplval; (void)scan_num("1", &tmplval); $$ = tmplval.opval; } | expr ; /* Inverted boolean expression */ iexpr : expr { $$ = invert(scalar($1)); } ; /* Expression with its own lexical scope */ mexpr : expr { $$ = $1; intro_my(); } ; mnexpr : nexpr { $$ = $1; intro_my(); } ; formname: BAREWORD { $$ = $1; } | /* NULL */ { $$ = NULL; } ; startsub: /* NULL */ /* start a regular subroutine scope */ { $$ = start_subparse(FALSE, 0); SAVEFREESV(PL_compcv); } ; startanonsub: /* NULL */ /* start an anonymous subroutine scope */ { $$ = start_subparse(FALSE, CVf_ANON); SAVEFREESV(PL_compcv); } ; startformsub: /* NULL */ /* start a format subroutine scope */ { $$ = start_subparse(TRUE, 0); SAVEFREESV(PL_compcv); } ; /* Name of a subroutine - must be a bareword, could be special */ subname : BAREWORD | PRIVATEREF ; /* Subroutine prototype */ proto : /* NULL */ { $$ = NULL; } | THING ; /* Optional list of subroutine attributes */ subattrlist: /* NULL */ { $$ = NULL; } | COLONATTR THING { $$ = $2; } | COLONATTR { $$ = NULL; } ; /* List of attributes for a "my" variable declaration */ myattrlist: COLONATTR THING { $$ = $2; } | COLONATTR { $$ = NULL; } ; /* -------------------------------------- * subroutine signature parsing */ /* the '' or 'foo' part of a '$' or '@foo' etc signature variable */ sigvarname: /* NULL */ { parser->in_my = 0; $$ = NULL; } | PRIVATEREF { parser->in_my = 0; $$ = $1; } ; sigslurpsigil: '@' { $$ = '@'; } | '%' { $$ = '%'; } /* @, %, @foo, %foo */ sigslurpelem: sigslurpsigil sigvarname sigdefault/* def only to catch errors */ { I32 sigil = $1; OP *var = $2; OP *defexpr = $3; if (parser->sig_slurpy) yyerror("Multiple slurpy parameters not allowed"); parser->sig_slurpy = (char)sigil; if (defexpr) yyerror("A slurpy parameter may not have " "a default value"); $$ = var ? newSTATEOP(0, NULL, var) : NULL; } ; /* default part of sub signature scalar element: i.e. '= default_expr' */ sigdefault: /* NULL */ { $$ = NULL; } | ASSIGNOP { $$ = newOP(OP_NULL, 0); } | ASSIGNOP term { $$ = $2; } /* subroutine signature scalar element: e.g. '$x', '$=', '$x = $default' */ sigscalarelem: '$' sigvarname sigdefault { OP *var = $2; OP *defexpr = $3; if (parser->sig_slurpy) yyerror("Slurpy parameter not last"); parser->sig_elems++; if (defexpr) { parser->sig_optelems++; if ( defexpr->op_type == OP_NULL && !(defexpr->op_flags & OPf_KIDS)) { /* handle '$=' special case */ if (var) yyerror("Optional parameter " "lacks default expression"); op_free(defexpr); } else { /* a normal '=default' expression */ OP *defop = (OP*)alloc_LOGOP(OP_ARGDEFELEM, defexpr, LINKLIST(defexpr)); /* re-purpose op_targ to hold @_ index */ defop->op_targ = (PADOFFSET)(parser->sig_elems - 1); if (var) { var->op_flags |= OPf_STACKED; (void)op_sibling_splice(var, NULL, 0, defop); scalar(defop); } else var = newUNOP(OP_NULL, 0, defop); LINKLIST(var); /* NB: normally the first child of a * logop is executed before the logop, * and it pushes a boolean result * ready for the logop. For ARGDEFELEM, * the op itself does the boolean * calculation, so set the first op to * it instead. */ var->op_next = defop; defexpr->op_next = var; } } else { if (parser->sig_optelems) yyerror("Mandatory parameter " "follows optional parameter"); } $$ = var ? newSTATEOP(0, NULL, var) : NULL; } ; /* subroutine signature element: e.g. '$x = $default' or '%h' */ sigelem: sigscalarelem { parser->in_my = KEY_sigvar; $$ = $1; } | sigslurpelem { parser->in_my = KEY_sigvar; $$ = $1; } ; /* list of subroutine signature elements */ siglist: siglist ',' { $$ = $1; } | siglist ',' sigelem { $$ = op_append_list(OP_LINESEQ, $1, $3); } | sigelem %prec PREC_LOW { $$ = $1; } ; /* () or (....) */ siglistornull: /* NULL */ { $$ = NULL; } | siglist { $$ = $1; } /* optional subroutine signature */ optsubsignature: /* NULL */ { $$ = NULL; } | subsignature { $$ = $1; } /* Subroutine signature */ subsignature: '(' subsigguts ')' { $$ = $2; } subsigguts: { ENTER; SAVEIV(parser->sig_elems); SAVEIV(parser->sig_optelems); SAVEI8(parser->sig_slurpy); parser->sig_elems = 0; parser->sig_optelems = 0; parser->sig_slurpy = 0; parser->in_my = KEY_sigvar; } siglistornull { OP *sigops = $2; struct op_argcheck_aux *aux; OP *check; if (!FEATURE_SIGNATURES_IS_ENABLED) Perl_croak(aTHX_ "Experimental " "subroutine signatures not enabled"); /* We shouldn't get here otherwise */ Perl_ck_warner_d(aTHX_ packWARN(WARN_EXPERIMENTAL__SIGNATURES), "The signatures feature is experimental"); aux = (struct op_argcheck_aux*) PerlMemShared_malloc( sizeof(struct op_argcheck_aux)); aux->params = parser->sig_elems; aux->opt_params = parser->sig_optelems; aux->slurpy = parser->sig_slurpy; check = newUNOP_AUX(OP_ARGCHECK, 0, NULL, (UNOP_AUX_item *)aux); sigops = op_prepend_elem(OP_LINESEQ, check, sigops); sigops = op_prepend_elem(OP_LINESEQ, newSTATEOP(0, NULL, NULL), sigops); /* a nextstate at the end handles context * correctly for an empty sub body */ sigops = op_append_elem(OP_LINESEQ, sigops, newSTATEOP(0, NULL, NULL)); /* wrap the list of arg ops in a NULL aux op. This serves two purposes. First, it makes the arg list a separate subtree from the body of the sub, and secondly the null op may in future be upgraded to an OP_SIGNATURE when implemented. For now leave it as ex-argcheck */ $$ = newUNOP_AUX(OP_ARGCHECK, 0, sigops, NULL); op_null($$); parser->in_my = 0; /* tell the toker that attrributes can follow * this sig, but only so that the toker * can skip through any (illegal) trailing * attribute text then give a useful error * message about "attributes before sig", * rather than falling over ina mess at * unrecognised syntax. */ parser->expect = XATTRBLOCK; parser->sig_seen = TRUE; LEAVE; } ; /* Optional subroutine body (for named subroutine declaration) */ optsubbody: subbody { $$ = $1; } | ';' { $$ = NULL; } ; /* Subroutine body (without signature) */ subbody: remember '{' stmtseq '}' { if (parser->copline > (line_t)$2) parser->copline = (line_t)$2; $$ = block_end($1, $3); } ; /* optional [ Subroutine body with optional signature ] (for named * subroutine declaration) */ optsigsubbody: sigsubbody { $$ = $1; } | ';' { $$ = NULL; } /* Subroutine body with optional signature */ sigsubbody: remember optsubsignature '{' stmtseq '}' { if (parser->copline > (line_t)$3) parser->copline = (line_t)$3; $$ = block_end($1, op_append_list(OP_LINESEQ, $2, $4)); } ; /* Ordinary expressions; logical combinations */ expr : expr ANDOP expr { $$ = newLOGOP(OP_AND, 0, $1, $3); } | expr OROP expr { $$ = newLOGOP($2, 0, $1, $3); } | expr DOROP expr { $$ = newLOGOP(OP_DOR, 0, $1, $3); } | listexpr %prec PREC_LOW ; /* Expressions are a list of terms joined by commas */ listexpr: listexpr ',' { $$ = $1; } | listexpr ',' term { OP* term = $3; $$ = op_append_elem(OP_LIST, $1, term); } | term %prec PREC_LOW ; /* List operators */ listop : LSTOP indirob listexpr /* map {...} @args or print $fh @args */ { $$ = op_convert_list($1, OPf_STACKED, op_prepend_elem(OP_LIST, newGVREF($1,$2), $3) ); } | FUNC '(' indirob expr ')' /* print ($fh @args */ { $$ = op_convert_list($1, OPf_STACKED, op_prepend_elem(OP_LIST, newGVREF($1,$3), $4) ); } | term ARROW method '(' optexpr ')' /* $foo->bar(list) */ { $$ = op_convert_list(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, op_prepend_elem(OP_LIST, scalar($1), $5), newMETHOP(OP_METHOD, 0, $3))); } | term ARROW method /* $foo->bar */ { $$ = op_convert_list(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, scalar($1), newMETHOP(OP_METHOD, 0, $3))); } | METHOD indirob optlistexpr /* new Class @args */ { $$ = op_convert_list(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, op_prepend_elem(OP_LIST, $2, $3), newMETHOP(OP_METHOD, 0, $1))); } | FUNCMETH indirob '(' optexpr ')' /* method $object (@args) */ { $$ = op_convert_list(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, op_prepend_elem(OP_LIST, $2, $4), newMETHOP(OP_METHOD, 0, $1))); } | LSTOP optlistexpr /* print @args */ { $$ = op_convert_list($1, 0, $2); } | FUNC '(' optexpr ')' /* print (@args) */ { $$ = op_convert_list($1, 0, $3); } | FUNC SUBLEXSTART optexpr SUBLEXEND /* uc($arg) from "\U..." */ { $$ = op_convert_list($1, 0, $3); } | LSTOPSUB startanonsub block /* sub f(&@); f { foo } ... */ { SvREFCNT_inc_simple_void(PL_compcv); $$ = newANONATTRSUB($2, 0, NULL, $3); } optlistexpr %prec LSTOP /* ... @bar */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, op_prepend_elem(OP_LIST, $4, $5), $1)); } ; /* Names of methods. May use $object->$methodname */ method : METHOD | scalar ; /* Some kind of subscripted expression */ subscripted: gelem '{' expr ';' '}' /* *main::{something} */ /* In this and all the hash accessors, ';' is * provided by the tokeniser */ { $$ = newBINOP(OP_GELEM, 0, $1, scalar($3)); } | scalar '[' expr ']' /* $array[$element] */ { $$ = newBINOP(OP_AELEM, 0, oopsAV($1), scalar($3)); } | term ARROW '[' expr ']' /* somearef->[$element] */ { $$ = newBINOP(OP_AELEM, 0, ref(newAVREF($1),OP_RV2AV), scalar($4)); } | subscripted '[' expr ']' /* $foo->[$bar]->[$baz] */ { $$ = newBINOP(OP_AELEM, 0, ref(newAVREF($1),OP_RV2AV), scalar($3)); } | scalar '{' expr ';' '}' /* $foo{bar();} */ { $$ = newBINOP(OP_HELEM, 0, oopsHV($1), jmaybe($3)); } | term ARROW '{' expr ';' '}' /* somehref->{bar();} */ { $$ = newBINOP(OP_HELEM, 0, ref(newHVREF($1),OP_RV2HV), jmaybe($4)); } | subscripted '{' expr ';' '}' /* $foo->[bar]->{baz;} */ { $$ = newBINOP(OP_HELEM, 0, ref(newHVREF($1),OP_RV2HV), jmaybe($3)); } | term ARROW '(' ')' /* $subref->() */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, newCVREF(0, scalar($1))); if (parser->expect == XBLOCK) parser->expect = XOPERATOR; } | term ARROW '(' expr ')' /* $subref->(@args) */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, $4, newCVREF(0, scalar($1)))); if (parser->expect == XBLOCK) parser->expect = XOPERATOR; } | subscripted '(' expr ')' /* $foo->{bar}->(@args) */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, $3, newCVREF(0, scalar($1)))); if (parser->expect == XBLOCK) parser->expect = XOPERATOR; } | subscripted '(' ')' /* $foo->{bar}->() */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, newCVREF(0, scalar($1))); if (parser->expect == XBLOCK) parser->expect = XOPERATOR; } | '(' expr ')' '[' expr ']' /* list slice */ { $$ = newSLICEOP(0, $5, $2); } | QWLIST '[' expr ']' /* list literal slice */ { $$ = newSLICEOP(0, $3, $1); } | '(' ')' '[' expr ']' /* empty list slice! */ { $$ = newSLICEOP(0, $4, NULL); } ; /* Binary operators between terms */ termbinop: term ASSIGNOP term /* $x = $y, $x += $y */ { $$ = newASSIGNOP(OPf_STACKED, $1, $2, $3); } | term POWOP term /* $x ** $y */ { $$ = newBINOP($2, 0, scalar($1), scalar($3)); } | term MULOP term /* $x * $y, $x x $y */ { if ($2 != OP_REPEAT) scalar($1); $$ = newBINOP($2, 0, $1, scalar($3)); } | term ADDOP term /* $x + $y */ { $$ = newBINOP($2, 0, scalar($1), scalar($3)); } | term SHIFTOP term /* $x >> $y, $x << $y */ { $$ = newBINOP($2, 0, scalar($1), scalar($3)); } | termrelop %prec PREC_LOW /* $x > $y, etc. */ { $$ = $1; } | termeqop %prec PREC_LOW /* $x == $y, $x cmp $y */ { $$ = $1; } | term BITANDOP term /* $x & $y */ { $$ = newBINOP($2, 0, scalar($1), scalar($3)); } | term BITOROP term /* $x | $y */ { $$ = newBINOP($2, 0, scalar($1), scalar($3)); } | term DOTDOT term /* $x..$y, $x...$y */ { $$ = newRANGE($2, scalar($1), scalar($3)); } | term ANDAND term /* $x && $y */ { $$ = newLOGOP(OP_AND, 0, $1, $3); } | term OROR term /* $x || $y */ { $$ = newLOGOP(OP_OR, 0, $1, $3); } | term DORDOR term /* $x // $y */ { $$ = newLOGOP(OP_DOR, 0, $1, $3); } | term MATCHOP term /* $x =~ /$y/ */ { $$ = bind_match($2, $1, $3); } ; termrelop: relopchain %prec PREC_LOW { $$ = cmpchain_finish($1); } | term NCRELOP term { $$ = newBINOP($2, 0, scalar($1), scalar($3)); } | termrelop NCRELOP { yyerror("syntax error"); YYERROR; } | termrelop CHRELOP { yyerror("syntax error"); YYERROR; } ; relopchain: term CHRELOP term { $$ = cmpchain_start($2, $1, $3); } | relopchain CHRELOP term { $$ = cmpchain_extend($2, $1, $3); } ; termeqop: eqopchain %prec PREC_LOW { $$ = cmpchain_finish($1); } | term NCEQOP term { $$ = newBINOP($2, 0, scalar($1), scalar($3)); } | termeqop NCEQOP { yyerror("syntax error"); YYERROR; } | termeqop CHEQOP { yyerror("syntax error"); YYERROR; } ; eqopchain: term CHEQOP term { $$ = cmpchain_start($2, $1, $3); } | eqopchain CHEQOP term { $$ = cmpchain_extend($2, $1, $3); } ; /* Unary operators and terms */ termunop : '-' term %prec UMINUS /* -$x */ { $$ = newUNOP(OP_NEGATE, 0, scalar($2)); } | '+' term %prec UMINUS /* +$x */ { $$ = $2; } | '!' term /* !$x */ { $$ = newUNOP(OP_NOT, 0, scalar($2)); } | '~' term /* ~$x */ { $$ = newUNOP($1, 0, scalar($2)); } | term POSTINC /* $x++ */ { $$ = newUNOP(OP_POSTINC, 0, op_lvalue(scalar($1), OP_POSTINC)); } | term POSTDEC /* $x-- */ { $$ = newUNOP(OP_POSTDEC, 0, op_lvalue(scalar($1), OP_POSTDEC));} | term POSTJOIN /* implicit join after interpolated ->@ */ { $$ = op_convert_list(OP_JOIN, 0, op_append_elem( OP_LIST, newSVREF(scalar( newSVOP(OP_CONST,0, newSVpvs("\"")) )), $1 )); } | PREINC term /* ++$x */ { $$ = newUNOP(OP_PREINC, 0, op_lvalue(scalar($2), OP_PREINC)); } | PREDEC term /* --$x */ { $$ = newUNOP(OP_PREDEC, 0, op_lvalue(scalar($2), OP_PREDEC)); } ; /* Constructors for anonymous data */ anonymous: '[' expr ']' { $$ = newANONLIST($2); } | '[' ']' { $$ = newANONLIST(NULL);} | HASHBRACK expr ';' '}' %prec '(' /* { foo => "Bar" } */ { $$ = newANONHASH($2); } | HASHBRACK ';' '}' %prec '(' /* { } (';' by tokener) */ { $$ = newANONHASH(NULL); } | ANONSUB startanonsub proto subattrlist subbody %prec '(' { SvREFCNT_inc_simple_void(PL_compcv); $$ = newANONATTRSUB($2, $3, $4, $5); } | ANON_SIGSUB startanonsub subattrlist sigsubbody %prec '(' { SvREFCNT_inc_simple_void(PL_compcv); $$ = newANONATTRSUB($2, NULL, $3, $4); } ; /* Things called with "do" */ termdo : DO term %prec UNIOP /* do $filename */ { $$ = dofile($2, $1);} | DO block %prec '(' /* do { code */ { $$ = newUNOP(OP_NULL, OPf_SPECIAL, op_scope($2));} ; term : termbinop | termunop | anonymous | termdo | term '?' term ':' term { $$ = newCONDOP(0, $1, $3, $5); } | REFGEN term /* \$x, \@y, \%z */ { $$ = newUNOP(OP_REFGEN, 0, $2); } | MY REFGEN term { $$ = newUNOP(OP_REFGEN, 0, localize($3,1)); } | myattrterm %prec UNIOP { $$ = $1; } | LOCAL term %prec UNIOP { $$ = localize($2,0); } | '(' expr ')' { $$ = sawparens($2); } | QWLIST { $$ = $1; } | '(' ')' { $$ = sawparens(newNULLLIST()); } | scalar %prec '(' { $$ = $1; } | star %prec '(' { $$ = $1; } | hsh %prec '(' { $$ = $1; } | ary %prec '(' { $$ = $1; } | arylen %prec '(' /* $#x, $#{ something } */ { $$ = newUNOP(OP_AV2ARYLEN, 0, ref($1, OP_AV2ARYLEN));} | subscripted { $$ = $1; } | sliceme '[' expr ']' /* array slice */ { $$ = op_prepend_elem(OP_ASLICE, newOP(OP_PUSHMARK, 0), newLISTOP(OP_ASLICE, 0, list($3), ref($1, OP_ASLICE))); if ($$ && $1) $$->op_private |= $1->op_private & OPpSLICEWARNING; } | kvslice '[' expr ']' /* array key/value slice */ { $$ = op_prepend_elem(OP_KVASLICE, newOP(OP_PUSHMARK, 0), newLISTOP(OP_KVASLICE, 0, list($3), ref(oopsAV($1), OP_KVASLICE))); if ($$ && $1) $$->op_private |= $1->op_private & OPpSLICEWARNING; } | sliceme '{' expr ';' '}' /* @hash{@keys} */ { $$ = op_prepend_elem(OP_HSLICE, newOP(OP_PUSHMARK, 0), newLISTOP(OP_HSLICE, 0, list($3), ref(oopsHV($1), OP_HSLICE))); if ($$ && $1) $$->op_private |= $1->op_private & OPpSLICEWARNING; } | kvslice '{' expr ';' '}' /* %hash{@keys} */ { $$ = op_prepend_elem(OP_KVHSLICE, newOP(OP_PUSHMARK, 0), newLISTOP(OP_KVHSLICE, 0, list($3), ref($1, OP_KVHSLICE))); if ($$ && $1) $$->op_private |= $1->op_private & OPpSLICEWARNING; } | THING %prec '(' { $$ = $1; } | amper /* &foo; */ { $$ = newUNOP(OP_ENTERSUB, 0, scalar($1)); } | amper '(' ')' /* &foo() or foo() */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, scalar($1)); } | amper '(' expr ')' /* &foo(@args) or foo(@args) */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, $3, scalar($1))); } | NOAMP subname optlistexpr /* foo @args (no parens) */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, $3, scalar($2))); } | term ARROW '$' '*' { $$ = newSVREF($1); } | term ARROW '@' '*' { $$ = newAVREF($1); } | term ARROW '%' '*' { $$ = newHVREF($1); } | term ARROW '&' '*' { $$ = newUNOP(OP_ENTERSUB, 0, scalar(newCVREF($3,$1))); } | term ARROW '*' '*' %prec '(' { $$ = newGVREF(0,$1); } | LOOPEX /* loop exiting command (goto, last, dump, etc) */ { $$ = newOP($1, OPf_SPECIAL); PL_hints |= HINT_BLOCK_SCOPE; } | LOOPEX term { $$ = newLOOPEX($1,$2); } | NOTOP listexpr /* not $foo */ { $$ = newUNOP(OP_NOT, 0, scalar($2)); } | UNIOP /* Unary op, $_ implied */ { $$ = newOP($1, 0); } | UNIOP block /* eval { foo }* */ { $$ = newUNOP($1, 0, $2); } | UNIOP term /* Unary op */ { $$ = newUNOP($1, 0, $2); } | REQUIRE /* require, $_ implied */ { $$ = newOP(OP_REQUIRE, $1 ? OPf_SPECIAL : 0); } | REQUIRE term /* require Foo */ { $$ = newUNOP(OP_REQUIRE, $1 ? OPf_SPECIAL : 0, $2); } | UNIOPSUB { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, scalar($1)); } | UNIOPSUB term /* Sub treated as unop */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, op_append_elem(OP_LIST, $2, scalar($1))); } | FUNC0 /* Nullary operator */ { $$ = newOP($1, 0); } | FUNC0 '(' ')' { $$ = newOP($1, 0);} | FUNC0OP /* Same as above, but op created in toke.c */ { $$ = $1; } | FUNC0OP '(' ')' { $$ = $1; } | FUNC0SUB /* Sub treated as nullop */ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, scalar($1)); } | FUNC1 '(' ')' /* not () */ { $$ = ($1 == OP_NOT) ? newUNOP($1, 0, newSVOP(OP_CONST, 0, newSViv(0))) : newOP($1, OPf_SPECIAL); } | FUNC1 '(' expr ')' /* not($foo) */ { $$ = newUNOP($1, 0, $3); } | PMFUNC /* m//, s///, qr//, tr/// */ { if ( $1->op_type != OP_TRANS && $1->op_type != OP_TRANSR && (((PMOP*)$1)->op_pmflags & PMf_HAS_CV)) { $$ = start_subparse(FALSE, CVf_ANON); SAVEFREESV(PL_compcv); } else $$ = 0; } SUBLEXSTART listexpr optrepl SUBLEXEND { $$ = pmruntime($1, $4, $5, 1, $2); } | BAREWORD | listop | PLUGEXPR ; /* "my" declarations, with optional attributes */ myattrterm: MY myterm myattrlist { $$ = my_attrs($2,$3); } | MY myterm { $$ = localize($2,1); } | MY REFGEN myterm myattrlist { $$ = newUNOP(OP_REFGEN, 0, my_attrs($3,$4)); } ; /* Things that can be "my"'d */ myterm : '(' expr ')' { $$ = sawparens($2); } | '(' ')' { $$ = sawparens(newNULLLIST()); } | scalar %prec '(' { $$ = $1; } | hsh %prec '(' { $$ = $1; } | ary %prec '(' { $$ = $1; } ; /* Basic list expressions */ optlistexpr: /* NULL */ %prec PREC_LOW { $$ = NULL; } | listexpr %prec PREC_LOW { $$ = $1; } ; optexpr: /* NULL */ { $$ = NULL; } | expr { $$ = $1; } ; optrepl: /* NULL */ { $$ = NULL; } | '/' expr { $$ = $2; } ; /* A little bit of trickery to make "for my $foo (@bar)" actually be lexical */ my_scalar: scalar { parser->in_my = 0; $$ = my($1); } ; my_var : scalar | ary | hsh ; refgen_topic: my_var | amper ; my_refgen: MY REFGEN | REFGEN MY ; amper : '&' indirob { $$ = newCVREF($1,$2); } ; scalar : '$' indirob { $$ = newSVREF($2); } ; ary : '@' indirob { $$ = newAVREF($2); if ($$) $$->op_private |= $1; } ; hsh : '%' indirob { $$ = newHVREF($2); if ($$) $$->op_private |= $1; } ; arylen : DOLSHARP indirob { $$ = newAVREF($2); } | term ARROW DOLSHARP '*' { $$ = newAVREF($1); } ; star : '*' indirob { $$ = newGVREF(0,$2); } ; sliceme : ary | term ARROW '@' { $$ = newAVREF($1); } ; kvslice : hsh | term ARROW '%' { $$ = newHVREF($1); } ; gelem : star | term ARROW '*' { $$ = newGVREF(0,$1); } ; /* Indirect objects */ indirob : BAREWORD { $$ = scalar($1); } | scalar %prec PREC_LOW { $$ = scalar($1); } | block { $$ = op_scope($1); } | PRIVATEREF { $$ = $1; } ;