3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
12 * 'It all comes from here, the stench and the peril.' --Frodo
14 * [p.719 of _The Lord of the Rings_, IV/ix: "Shelob's Lair"]
18 * This file is the lexer for Perl. It's closely linked to the
21 * The main routine is yylex(), which returns the next token.
25 =head1 Lexer interface
27 This is the lower layer of the Perl parser, managing characters and tokens.
29 =for apidoc AmU|yy_parser *|PL_parser
31 Pointer to a structure encapsulating the state of the parsing operation
32 currently in progress. The pointer can be locally changed to perform
33 a nested parse without interfering with the state of an outer parse.
34 Individual members of C<PL_parser> have their own documentation.
40 #define PERL_IN_TOKE_C
42 #include "dquote_static.c"
44 #define new_constant(a,b,c,d,e,f,g) \
45 S_new_constant(aTHX_ a,b,STR_WITH_LEN(c),d,e,f, g)
47 #define pl_yylval (PL_parser->yylval)
49 /* XXX temporary backwards compatibility */
50 #define PL_lex_brackets (PL_parser->lex_brackets)
51 #define PL_lex_allbrackets (PL_parser->lex_allbrackets)
52 #define PL_lex_fakeeof (PL_parser->lex_fakeeof)
53 #define PL_lex_brackstack (PL_parser->lex_brackstack)
54 #define PL_lex_casemods (PL_parser->lex_casemods)
55 #define PL_lex_casestack (PL_parser->lex_casestack)
56 #define PL_lex_defer (PL_parser->lex_defer)
57 #define PL_lex_dojoin (PL_parser->lex_dojoin)
58 #define PL_lex_expect (PL_parser->lex_expect)
59 #define PL_lex_formbrack (PL_parser->lex_formbrack)
60 #define PL_lex_inpat (PL_parser->lex_inpat)
61 #define PL_lex_inwhat (PL_parser->lex_inwhat)
62 #define PL_lex_op (PL_parser->lex_op)
63 #define PL_lex_repl (PL_parser->lex_repl)
64 #define PL_lex_starts (PL_parser->lex_starts)
65 #define PL_lex_stuff (PL_parser->lex_stuff)
66 #define PL_multi_start (PL_parser->multi_start)
67 #define PL_multi_open (PL_parser->multi_open)
68 #define PL_multi_close (PL_parser->multi_close)
69 #define PL_preambled (PL_parser->preambled)
70 #define PL_sublex_info (PL_parser->sublex_info)
71 #define PL_linestr (PL_parser->linestr)
72 #define PL_expect (PL_parser->expect)
73 #define PL_copline (PL_parser->copline)
74 #define PL_bufptr (PL_parser->bufptr)
75 #define PL_oldbufptr (PL_parser->oldbufptr)
76 #define PL_oldoldbufptr (PL_parser->oldoldbufptr)
77 #define PL_linestart (PL_parser->linestart)
78 #define PL_bufend (PL_parser->bufend)
79 #define PL_last_uni (PL_parser->last_uni)
80 #define PL_last_lop (PL_parser->last_lop)
81 #define PL_last_lop_op (PL_parser->last_lop_op)
82 #define PL_lex_state (PL_parser->lex_state)
83 #define PL_rsfp (PL_parser->rsfp)
84 #define PL_rsfp_filters (PL_parser->rsfp_filters)
85 #define PL_in_my (PL_parser->in_my)
86 #define PL_in_my_stash (PL_parser->in_my_stash)
87 #define PL_tokenbuf (PL_parser->tokenbuf)
88 #define PL_multi_end (PL_parser->multi_end)
89 #define PL_error_count (PL_parser->error_count)
92 # define PL_endwhite (PL_parser->endwhite)
93 # define PL_faketokens (PL_parser->faketokens)
94 # define PL_lasttoke (PL_parser->lasttoke)
95 # define PL_nextwhite (PL_parser->nextwhite)
96 # define PL_realtokenstart (PL_parser->realtokenstart)
97 # define PL_skipwhite (PL_parser->skipwhite)
98 # define PL_thisclose (PL_parser->thisclose)
99 # define PL_thismad (PL_parser->thismad)
100 # define PL_thisopen (PL_parser->thisopen)
101 # define PL_thisstuff (PL_parser->thisstuff)
102 # define PL_thistoken (PL_parser->thistoken)
103 # define PL_thiswhite (PL_parser->thiswhite)
104 # define PL_thiswhite (PL_parser->thiswhite)
105 # define PL_nexttoke (PL_parser->nexttoke)
106 # define PL_curforce (PL_parser->curforce)
108 # define PL_nexttoke (PL_parser->nexttoke)
109 # define PL_nexttype (PL_parser->nexttype)
110 # define PL_nextval (PL_parser->nextval)
113 static const char* const ident_too_long = "Identifier too long";
116 # define CURMAD(slot,sv) if (PL_madskills) { curmad(slot,sv); sv = 0; }
117 # define NEXTVAL_NEXTTOKE PL_nexttoke[PL_curforce].next_val
119 # define CURMAD(slot,sv)
120 # define NEXTVAL_NEXTTOKE PL_nextval[PL_nexttoke]
123 #define XENUMMASK 0x3f
124 #define XFAKEEOF 0x40
125 #define XFAKEBRACK 0x80
127 #ifdef USE_UTF8_SCRIPTS
128 # define UTF (!IN_BYTES)
130 # define UTF ((PL_linestr && DO_UTF8(PL_linestr)) || ( !(PL_parser->lex_flags & LEX_IGNORE_UTF8_HINTS) && (PL_hints & HINT_UTF8)))
133 /* The maximum number of characters preceding the unrecognized one to display */
134 #define UNRECOGNIZED_PRECEDE_COUNT 10
136 /* In variables named $^X, these are the legal values for X.
137 * 1999-02-27 mjd-perl-patch@plover.com */
138 #define isCONTROLVAR(x) (isUPPER(x) || strchr("[\\]^_?", (x)))
140 #define SPACE_OR_TAB(c) isBLANK_A(c)
142 /* LEX_* are values for PL_lex_state, the state of the lexer.
143 * They are arranged oddly so that the guard on the switch statement
144 * can get by with a single comparison (if the compiler is smart enough).
146 * These values refer to the various states within a sublex parse,
147 * i.e. within a double quotish string
150 /* #define LEX_NOTPARSING 11 is done in perl.h. */
152 #define LEX_NORMAL 10 /* normal code (ie not within "...") */
153 #define LEX_INTERPNORMAL 9 /* code within a string, eg "$foo[$x+1]" */
154 #define LEX_INTERPCASEMOD 8 /* expecting a \U, \Q or \E etc */
155 #define LEX_INTERPPUSH 7 /* starting a new sublex parse level */
156 #define LEX_INTERPSTART 6 /* expecting the start of a $var */
158 /* at end of code, eg "$x" followed by: */
159 #define LEX_INTERPEND 5 /* ... eg not one of [, { or -> */
160 #define LEX_INTERPENDMAYBE 4 /* ... eg one of [, { or -> */
162 #define LEX_INTERPCONCAT 3 /* expecting anything, eg at start of
163 string or after \E, $foo, etc */
164 #define LEX_INTERPCONST 2 /* NOT USED */
165 #define LEX_FORMLINE 1 /* expecting a format line */
166 #define LEX_KNOWNEXT 0 /* next token known; just return it */
170 static const char* const lex_state_names[] = {
189 #include "keywords.h"
191 /* CLINE is a macro that ensures PL_copline has a sane value */
196 #define CLINE (PL_copline = (CopLINE(PL_curcop) < PL_copline ? CopLINE(PL_curcop) : PL_copline))
199 # define SKIPSPACE0(s) skipspace0(s)
200 # define SKIPSPACE1(s) skipspace1(s)
201 # define SKIPSPACE2(s,tsv) skipspace2(s,&tsv)
202 # define PEEKSPACE(s) skipspace2(s,0)
204 # define SKIPSPACE0(s) skipspace(s)
205 # define SKIPSPACE1(s) skipspace(s)
206 # define SKIPSPACE2(s,tsv) skipspace(s)
207 # define PEEKSPACE(s) skipspace(s)
211 * Convenience functions to return different tokens and prime the
212 * lexer for the next token. They all take an argument.
214 * TOKEN : generic token (used for '(', DOLSHARP, etc)
215 * OPERATOR : generic operator
216 * AOPERATOR : assignment operator
217 * PREBLOCK : beginning the block after an if, while, foreach, ...
218 * PRETERMBLOCK : beginning a non-code-defining {} block (eg, hash ref)
219 * PREREF : *EXPR where EXPR is not a simple identifier
220 * TERM : expression term
221 * LOOPX : loop exiting command (goto, last, dump, etc)
222 * FTST : file test operator
223 * FUN0 : zero-argument function
224 * FUN0OP : zero-argument function, with its op created in this file
225 * FUN1 : not used, except for not, which isn't a UNIOP
226 * BOop : bitwise or or xor
228 * SHop : shift operator
229 * PWop : power operator
230 * PMop : pattern-matching operator
231 * Aop : addition-level operator
232 * Mop : multiplication-level operator
233 * Eop : equality-testing operator
234 * Rop : relational operator <= != gt
236 * Also see LOP and lop() below.
239 #ifdef DEBUGGING /* Serve -DT. */
240 # define REPORT(retval) tokereport((I32)retval, &pl_yylval)
242 # define REPORT(retval) (retval)
245 #define TOKEN(retval) return ( PL_bufptr = s, REPORT(retval))
246 #define OPERATOR(retval) return (PL_expect = XTERM, PL_bufptr = s, REPORT(retval))
247 #define AOPERATOR(retval) return ao((PL_expect = XTERM, PL_bufptr = s, REPORT(retval)))
248 #define PREBLOCK(retval) return (PL_expect = XBLOCK,PL_bufptr = s, REPORT(retval))
249 #define PRETERMBLOCK(retval) return (PL_expect = XTERMBLOCK,PL_bufptr = s, REPORT(retval))
250 #define PREREF(retval) return (PL_expect = XREF,PL_bufptr = s, REPORT(retval))
251 #define TERM(retval) return (CLINE, PL_expect = XOPERATOR, PL_bufptr = s, REPORT(retval))
252 #define LOOPX(f) return (pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)LOOPEX))
253 #define FTST(f) return (pl_yylval.ival=f, PL_expect=XTERMORDORDOR, PL_bufptr=s, REPORT((int)UNIOP))
254 #define FUN0(f) return (pl_yylval.ival=f, PL_expect=XOPERATOR, PL_bufptr=s, REPORT((int)FUNC0))
255 #define FUN0OP(f) return (pl_yylval.opval=f, CLINE, PL_expect=XOPERATOR, PL_bufptr=s, REPORT((int)FUNC0OP))
256 #define FUN1(f) return (pl_yylval.ival=f, PL_expect=XOPERATOR, PL_bufptr=s, REPORT((int)FUNC1))
257 #define BOop(f) return ao((pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)BITOROP)))
258 #define BAop(f) return ao((pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)BITANDOP)))
259 #define SHop(f) return ao((pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)SHIFTOP)))
260 #define PWop(f) return ao((pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)POWOP)))
261 #define PMop(f) return(pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)MATCHOP))
262 #define Aop(f) return ao((pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)ADDOP)))
263 #define Mop(f) return ao((pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)MULOP)))
264 #define Eop(f) return (pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)EQOP))
265 #define Rop(f) return (pl_yylval.ival=f, PL_expect=XTERM, PL_bufptr=s, REPORT((int)RELOP))
267 /* This bit of chicanery makes a unary function followed by
268 * a parenthesis into a function with one argument, highest precedence.
269 * The UNIDOR macro is for unary functions that can be followed by the //
270 * operator (such as C<shift // 0>).
272 #define UNI3(f,x,have_x) { \
273 pl_yylval.ival = f; \
274 if (have_x) PL_expect = x; \
276 PL_last_uni = PL_oldbufptr; \
277 PL_last_lop_op = f; \
279 return REPORT( (int)FUNC1 ); \
281 return REPORT( *s=='(' ? (int)FUNC1 : (int)UNIOP ); \
283 #define UNI(f) UNI3(f,XTERM,1)
284 #define UNIDOR(f) UNI3(f,XTERMORDORDOR,1)
285 #define UNIPROTO(f,optional) { \
286 if (optional) PL_last_uni = PL_oldbufptr; \
290 #define UNIBRACK(f) UNI3(f,0,0)
292 /* grandfather return to old style */
295 if (!PL_lex_allbrackets && PL_lex_fakeeof > LEX_FAKEEOF_LOWLOGIC) \
296 PL_lex_fakeeof = LEX_FAKEEOF_LOWLOGIC; \
297 pl_yylval.ival = (f); \
303 #define COPLINE_INC_WITH_HERELINES \
305 CopLINE_inc(PL_curcop); \
306 if (PL_parser->lex_shared->herelines) \
307 CopLINE(PL_curcop) += PL_parser->lex_shared->herelines, \
308 PL_parser->lex_shared->herelines = 0; \
314 /* how to interpret the pl_yylval associated with the token */
318 TOKENTYPE_OPNUM, /* pl_yylval.ival contains an opcode number */
323 static struct debug_tokens {
325 enum token_type type;
327 } const debug_tokens[] =
329 { ADDOP, TOKENTYPE_OPNUM, "ADDOP" },
330 { ANDAND, TOKENTYPE_NONE, "ANDAND" },
331 { ANDOP, TOKENTYPE_NONE, "ANDOP" },
332 { ANONSUB, TOKENTYPE_IVAL, "ANONSUB" },
333 { ARROW, TOKENTYPE_NONE, "ARROW" },
334 { ASSIGNOP, TOKENTYPE_OPNUM, "ASSIGNOP" },
335 { BITANDOP, TOKENTYPE_OPNUM, "BITANDOP" },
336 { BITOROP, TOKENTYPE_OPNUM, "BITOROP" },
337 { COLONATTR, TOKENTYPE_NONE, "COLONATTR" },
338 { CONTINUE, TOKENTYPE_NONE, "CONTINUE" },
339 { DEFAULT, TOKENTYPE_NONE, "DEFAULT" },
340 { DO, TOKENTYPE_NONE, "DO" },
341 { DOLSHARP, TOKENTYPE_NONE, "DOLSHARP" },
342 { DORDOR, TOKENTYPE_NONE, "DORDOR" },
343 { DOROP, TOKENTYPE_OPNUM, "DOROP" },
344 { DOTDOT, TOKENTYPE_IVAL, "DOTDOT" },
345 { ELSE, TOKENTYPE_NONE, "ELSE" },
346 { ELSIF, TOKENTYPE_IVAL, "ELSIF" },
347 { EQOP, TOKENTYPE_OPNUM, "EQOP" },
348 { FOR, TOKENTYPE_IVAL, "FOR" },
349 { FORMAT, TOKENTYPE_NONE, "FORMAT" },
350 { FORMLBRACK, TOKENTYPE_NONE, "FORMLBRACK" },
351 { FORMRBRACK, TOKENTYPE_NONE, "FORMRBRACK" },
352 { FUNC, TOKENTYPE_OPNUM, "FUNC" },
353 { FUNC0, TOKENTYPE_OPNUM, "FUNC0" },
354 { FUNC0OP, TOKENTYPE_OPVAL, "FUNC0OP" },
355 { FUNC0SUB, TOKENTYPE_OPVAL, "FUNC0SUB" },
356 { FUNC1, TOKENTYPE_OPNUM, "FUNC1" },
357 { FUNCMETH, TOKENTYPE_OPVAL, "FUNCMETH" },
358 { GIVEN, TOKENTYPE_IVAL, "GIVEN" },
359 { HASHBRACK, TOKENTYPE_NONE, "HASHBRACK" },
360 { IF, TOKENTYPE_IVAL, "IF" },
361 { LABEL, TOKENTYPE_PVAL, "LABEL" },
362 { LOCAL, TOKENTYPE_IVAL, "LOCAL" },
363 { LOOPEX, TOKENTYPE_OPNUM, "LOOPEX" },
364 { LSTOP, TOKENTYPE_OPNUM, "LSTOP" },
365 { LSTOPSUB, TOKENTYPE_OPVAL, "LSTOPSUB" },
366 { MATCHOP, TOKENTYPE_OPNUM, "MATCHOP" },
367 { METHOD, TOKENTYPE_OPVAL, "METHOD" },
368 { MULOP, TOKENTYPE_OPNUM, "MULOP" },
369 { MY, TOKENTYPE_IVAL, "MY" },
370 { NOAMP, TOKENTYPE_NONE, "NOAMP" },
371 { NOTOP, TOKENTYPE_NONE, "NOTOP" },
372 { OROP, TOKENTYPE_IVAL, "OROP" },
373 { OROR, TOKENTYPE_NONE, "OROR" },
374 { PACKAGE, TOKENTYPE_NONE, "PACKAGE" },
375 { PEG, TOKENTYPE_NONE, "PEG" },
376 { PLUGEXPR, TOKENTYPE_OPVAL, "PLUGEXPR" },
377 { PLUGSTMT, TOKENTYPE_OPVAL, "PLUGSTMT" },
378 { PMFUNC, TOKENTYPE_OPVAL, "PMFUNC" },
379 { POSTDEC, TOKENTYPE_NONE, "POSTDEC" },
380 { POSTINC, TOKENTYPE_NONE, "POSTINC" },
381 { POWOP, TOKENTYPE_OPNUM, "POWOP" },
382 { PREDEC, TOKENTYPE_NONE, "PREDEC" },
383 { PREINC, TOKENTYPE_NONE, "PREINC" },
384 { PRIVATEREF, TOKENTYPE_OPVAL, "PRIVATEREF" },
385 { QWLIST, TOKENTYPE_OPVAL, "QWLIST" },
386 { REFGEN, TOKENTYPE_NONE, "REFGEN" },
387 { RELOP, TOKENTYPE_OPNUM, "RELOP" },
388 { REQUIRE, TOKENTYPE_NONE, "REQUIRE" },
389 { SHIFTOP, TOKENTYPE_OPNUM, "SHIFTOP" },
390 { SUB, TOKENTYPE_NONE, "SUB" },
391 { THING, TOKENTYPE_OPVAL, "THING" },
392 { UMINUS, TOKENTYPE_NONE, "UMINUS" },
393 { UNIOP, TOKENTYPE_OPNUM, "UNIOP" },
394 { UNIOPSUB, TOKENTYPE_OPVAL, "UNIOPSUB" },
395 { UNLESS, TOKENTYPE_IVAL, "UNLESS" },
396 { UNTIL, TOKENTYPE_IVAL, "UNTIL" },
397 { USE, TOKENTYPE_IVAL, "USE" },
398 { WHEN, TOKENTYPE_IVAL, "WHEN" },
399 { WHILE, TOKENTYPE_IVAL, "WHILE" },
400 { WORD, TOKENTYPE_OPVAL, "WORD" },
401 { YADAYADA, TOKENTYPE_IVAL, "YADAYADA" },
402 { 0, TOKENTYPE_NONE, NULL }
405 /* dump the returned token in rv, plus any optional arg in pl_yylval */
408 S_tokereport(pTHX_ I32 rv, const YYSTYPE* lvalp)
412 PERL_ARGS_ASSERT_TOKEREPORT;
415 const char *name = NULL;
416 enum token_type type = TOKENTYPE_NONE;
417 const struct debug_tokens *p;
418 SV* const report = newSVpvs("<== ");
420 for (p = debug_tokens; p->token; p++) {
421 if (p->token == (int)rv) {
428 Perl_sv_catpv(aTHX_ report, name);
429 else if ((char)rv > ' ' && (char)rv <= '~')
431 Perl_sv_catpvf(aTHX_ report, "'%c'", (char)rv);
433 sv_catpvs(report, " (pending identifier)");
436 sv_catpvs(report, "EOF");
438 Perl_sv_catpvf(aTHX_ report, "?? %"IVdf, (IV)rv);
443 Perl_sv_catpvf(aTHX_ report, "(ival=%"IVdf")", (IV)lvalp->ival);
445 case TOKENTYPE_OPNUM:
446 Perl_sv_catpvf(aTHX_ report, "(ival=op_%s)",
447 PL_op_name[lvalp->ival]);
450 Perl_sv_catpvf(aTHX_ report, "(pval=\"%s\")", lvalp->pval);
452 case TOKENTYPE_OPVAL:
454 Perl_sv_catpvf(aTHX_ report, "(opval=op_%s)",
455 PL_op_name[lvalp->opval->op_type]);
456 if (lvalp->opval->op_type == OP_CONST) {
457 Perl_sv_catpvf(aTHX_ report, " %s",
458 SvPEEK(cSVOPx_sv(lvalp->opval)));
463 sv_catpvs(report, "(opval=null)");
466 PerlIO_printf(Perl_debug_log, "### %s\n\n", SvPV_nolen_const(report));
472 /* print the buffer with suitable escapes */
475 S_printbuf(pTHX_ const char *const fmt, const char *const s)
477 SV* const tmp = newSVpvs("");
479 PERL_ARGS_ASSERT_PRINTBUF;
481 PerlIO_printf(Perl_debug_log, fmt, pv_display(tmp, s, strlen(s), 0, 60));
488 S_deprecate_commaless_var_list(pTHX) {
490 deprecate("comma-less variable list");
491 return REPORT(','); /* grandfather non-comma-format format */
497 * This subroutine detects &&=, ||=, and //= and turns an ANDAND, OROR or DORDOR
498 * into an OP_ANDASSIGN, OP_ORASSIGN, or OP_DORASSIGN
502 S_ao(pTHX_ int toketype)
505 if (*PL_bufptr == '=') {
507 if (toketype == ANDAND)
508 pl_yylval.ival = OP_ANDASSIGN;
509 else if (toketype == OROR)
510 pl_yylval.ival = OP_ORASSIGN;
511 else if (toketype == DORDOR)
512 pl_yylval.ival = OP_DORASSIGN;
520 * When Perl expects an operator and finds something else, no_op
521 * prints the warning. It always prints "<something> found where
522 * operator expected. It prints "Missing semicolon on previous line?"
523 * if the surprise occurs at the start of the line. "do you need to
524 * predeclare ..." is printed out for code like "sub bar; foo bar $x"
525 * where the compiler doesn't know if foo is a method call or a function.
526 * It prints "Missing operator before end of line" if there's nothing
527 * after the missing operator, or "... before <...>" if there is something
528 * after the missing operator.
532 S_no_op(pTHX_ const char *const what, char *s)
535 char * const oldbp = PL_bufptr;
536 const bool is_first = (PL_oldbufptr == PL_linestart);
538 PERL_ARGS_ASSERT_NO_OP;
544 yywarn(Perl_form(aTHX_ "%s found where operator expected", what), UTF ? SVf_UTF8 : 0);
545 if (ckWARN_d(WARN_SYNTAX)) {
547 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
548 "\t(Missing semicolon on previous line?)\n");
549 else if (PL_oldoldbufptr && isIDFIRST_lazy_if(PL_oldoldbufptr,UTF)) {
551 for (t = PL_oldoldbufptr; (isWORDCHAR_lazy_if(t,UTF) || *t == ':');
552 t += UTF ? UTF8SKIP(t) : 1)
554 if (t < PL_bufptr && isSPACE(*t))
555 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
556 "\t(Do you need to predeclare %"UTF8f"?)\n",
557 UTF8fARG(UTF, t - PL_oldoldbufptr, PL_oldoldbufptr));
561 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
562 "\t(Missing operator before %"UTF8f"?)\n",
563 UTF8fARG(UTF, s - oldbp, oldbp));
571 * Complain about missing quote/regexp/heredoc terminator.
572 * If it's called with NULL then it cauterizes the line buffer.
573 * If we're in a delimited string and the delimiter is a control
574 * character, it's reformatted into a two-char sequence like ^C.
579 S_missingterm(pTHX_ char *s)
585 char * const nl = strrchr(s,'\n');
589 else if (isCNTRL(PL_multi_close)) {
591 tmpbuf[1] = (char)toCTRL(PL_multi_close);
596 *tmpbuf = (char)PL_multi_close;
600 q = strchr(s,'"') ? '\'' : '"';
601 Perl_croak(aTHX_ "Can't find string terminator %c%s%c anywhere before EOF",q,s,q);
607 * Check whether the named feature is enabled.
610 Perl_feature_is_enabled(pTHX_ const char *const name, STRLEN namelen)
613 char he_name[8 + MAX_FEATURE_LEN] = "feature_";
615 PERL_ARGS_ASSERT_FEATURE_IS_ENABLED;
617 assert(CURRENT_FEATURE_BUNDLE == FEATURE_BUNDLE_CUSTOM);
619 if (namelen > MAX_FEATURE_LEN)
621 memcpy(&he_name[8], name, namelen);
623 return cBOOL(cop_hints_fetch_pvn(PL_curcop, he_name, 8 + namelen, 0,
624 REFCOUNTED_HE_EXISTS));
628 * experimental text filters for win32 carriage-returns, utf16-to-utf8 and
629 * utf16-to-utf8-reversed.
632 #ifdef PERL_CR_FILTER
636 const char *s = SvPVX_const(sv);
637 const char * const e = s + SvCUR(sv);
639 PERL_ARGS_ASSERT_STRIP_RETURN;
641 /* outer loop optimized to do nothing if there are no CR-LFs */
643 if (*s++ == '\r' && *s == '\n') {
644 /* hit a CR-LF, need to copy the rest */
648 if (*s == '\r' && s[1] == '\n')
659 S_cr_textfilter(pTHX_ int idx, SV *sv, int maxlen)
661 const I32 count = FILTER_READ(idx+1, sv, maxlen);
662 if (count > 0 && !maxlen)
669 =for apidoc Amx|void|lex_start|SV *line|PerlIO *rsfp|U32 flags
671 Creates and initialises a new lexer/parser state object, supplying
672 a context in which to lex and parse from a new source of Perl code.
673 A pointer to the new state object is placed in L</PL_parser>. An entry
674 is made on the save stack so that upon unwinding the new state object
675 will be destroyed and the former value of L</PL_parser> will be restored.
676 Nothing else need be done to clean up the parsing context.
678 The code to be parsed comes from I<line> and I<rsfp>. I<line>, if
679 non-null, provides a string (in SV form) containing code to be parsed.
680 A copy of the string is made, so subsequent modification of I<line>
681 does not affect parsing. I<rsfp>, if non-null, provides an input stream
682 from which code will be read to be parsed. If both are non-null, the
683 code in I<line> comes first and must consist of complete lines of input,
684 and I<rsfp> supplies the remainder of the source.
686 The I<flags> parameter is reserved for future use. Currently it is only
687 used by perl internally, so extensions should always pass zero.
692 /* LEX_START_SAME_FILTER indicates that this is not a new file, so it
693 can share filters with the current parser.
694 LEX_START_DONT_CLOSE indicates that the file handle wasn't opened by the
695 caller, hence isn't owned by the parser, so shouldn't be closed on parser
696 destruction. This is used to handle the case of defaulting to reading the
697 script from the standard input because no filename was given on the command
698 line (without getting confused by situation where STDIN has been closed, so
699 the script handle is opened on fd 0) */
702 Perl_lex_start(pTHX_ SV *line, PerlIO *rsfp, U32 flags)
705 const char *s = NULL;
706 yy_parser *parser, *oparser;
707 if (flags && flags & ~LEX_START_FLAGS)
708 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_start");
710 /* create and initialise a parser */
712 Newxz(parser, 1, yy_parser);
713 parser->old_parser = oparser = PL_parser;
716 parser->stack = NULL;
718 parser->stack_size = 0;
720 /* on scope exit, free this parser and restore any outer one */
722 parser->saved_curcop = PL_curcop;
724 /* initialise lexer state */
727 parser->curforce = -1;
729 parser->nexttoke = 0;
731 parser->error_count = oparser ? oparser->error_count : 0;
732 parser->copline = NOLINE;
733 parser->lex_state = LEX_NORMAL;
734 parser->expect = XSTATE;
736 parser->rsfp_filters =
737 !(flags & LEX_START_SAME_FILTER) || !oparser
739 : MUTABLE_AV(SvREFCNT_inc(
740 oparser->rsfp_filters
741 ? oparser->rsfp_filters
742 : (oparser->rsfp_filters = newAV())
745 Newx(parser->lex_brackstack, 120, char);
746 Newx(parser->lex_casestack, 12, char);
747 *parser->lex_casestack = '\0';
748 Newxz(parser->lex_shared, 1, LEXSHARED);
752 s = SvPV_const(line, len);
753 parser->linestr = flags & LEX_START_COPIED
754 ? SvREFCNT_inc_simple_NN(line)
755 : newSVpvn_flags(s, len, SvUTF8(line));
756 sv_catpvs(parser->linestr, "\n;");
758 parser->linestr = newSVpvs("\n;");
760 parser->oldoldbufptr =
763 parser->linestart = SvPVX(parser->linestr);
764 parser->bufend = parser->bufptr + SvCUR(parser->linestr);
765 parser->last_lop = parser->last_uni = NULL;
766 parser->lex_flags = flags & (LEX_IGNORE_UTF8_HINTS|LEX_EVALBYTES
767 |LEX_DONT_CLOSE_RSFP);
769 parser->in_pod = parser->filtered = 0;
773 /* delete a parser object */
776 Perl_parser_free(pTHX_ const yy_parser *parser)
778 PERL_ARGS_ASSERT_PARSER_FREE;
780 PL_curcop = parser->saved_curcop;
781 SvREFCNT_dec(parser->linestr);
783 if (PL_parser->lex_flags & LEX_DONT_CLOSE_RSFP)
784 PerlIO_clearerr(parser->rsfp);
785 else if (parser->rsfp && (!parser->old_parser ||
786 (parser->old_parser && parser->rsfp != parser->old_parser->rsfp)))
787 PerlIO_close(parser->rsfp);
788 SvREFCNT_dec(parser->rsfp_filters);
789 SvREFCNT_dec(parser->lex_stuff);
790 SvREFCNT_dec(parser->sublex_info.repl);
792 Safefree(parser->lex_brackstack);
793 Safefree(parser->lex_casestack);
794 Safefree(parser->lex_shared);
795 PL_parser = parser->old_parser;
800 Perl_parser_free_nexttoke_ops(pTHX_ yy_parser *parser, OPSLAB *slab)
803 I32 nexttoke = parser->lasttoke;
805 I32 nexttoke = parser->nexttoke;
807 PERL_ARGS_ASSERT_PARSER_FREE_NEXTTOKE_OPS;
810 if (S_is_opval_token(parser->nexttoke[nexttoke].next_type
812 && parser->nexttoke[nexttoke].next_val.opval
813 && parser->nexttoke[nexttoke].next_val.opval->op_slabbed
814 && OpSLAB(parser->nexttoke[nexttoke].next_val.opval) == slab) {
815 op_free(parser->nexttoke[nexttoke].next_val.opval);
816 parser->nexttoke[nexttoke].next_val.opval = NULL;
819 if (S_is_opval_token(parser->nexttype[nexttoke] & 0xffff)
820 && parser->nextval[nexttoke].opval
821 && parser->nextval[nexttoke].opval->op_slabbed
822 && OpSLAB(parser->nextval[nexttoke].opval) == slab) {
823 op_free(parser->nextval[nexttoke].opval);
824 parser->nextval[nexttoke].opval = NULL;
832 =for apidoc AmxU|SV *|PL_parser-E<gt>linestr
834 Buffer scalar containing the chunk currently under consideration of the
835 text currently being lexed. This is always a plain string scalar (for
836 which C<SvPOK> is true). It is not intended to be used as a scalar by
837 normal scalar means; instead refer to the buffer directly by the pointer
838 variables described below.
840 The lexer maintains various C<char*> pointers to things in the
841 C<PL_parser-E<gt>linestr> buffer. If C<PL_parser-E<gt>linestr> is ever
842 reallocated, all of these pointers must be updated. Don't attempt to
843 do this manually, but rather use L</lex_grow_linestr> if you need to
844 reallocate the buffer.
846 The content of the text chunk in the buffer is commonly exactly one
847 complete line of input, up to and including a newline terminator,
848 but there are situations where it is otherwise. The octets of the
849 buffer may be intended to be interpreted as either UTF-8 or Latin-1.
850 The function L</lex_bufutf8> tells you which. Do not use the C<SvUTF8>
851 flag on this scalar, which may disagree with it.
853 For direct examination of the buffer, the variable
854 L</PL_parser-E<gt>bufend> points to the end of the buffer. The current
855 lexing position is pointed to by L</PL_parser-E<gt>bufptr>. Direct use
856 of these pointers is usually preferable to examination of the scalar
857 through normal scalar means.
859 =for apidoc AmxU|char *|PL_parser-E<gt>bufend
861 Direct pointer to the end of the chunk of text currently being lexed, the
862 end of the lexer buffer. This is equal to C<SvPVX(PL_parser-E<gt>linestr)
863 + SvCUR(PL_parser-E<gt>linestr)>. A NUL character (zero octet) is
864 always located at the end of the buffer, and does not count as part of
865 the buffer's contents.
867 =for apidoc AmxU|char *|PL_parser-E<gt>bufptr
869 Points to the current position of lexing inside the lexer buffer.
870 Characters around this point may be freely examined, within
871 the range delimited by C<SvPVX(L</PL_parser-E<gt>linestr>)> and
872 L</PL_parser-E<gt>bufend>. The octets of the buffer may be intended to be
873 interpreted as either UTF-8 or Latin-1, as indicated by L</lex_bufutf8>.
875 Lexing code (whether in the Perl core or not) moves this pointer past
876 the characters that it consumes. It is also expected to perform some
877 bookkeeping whenever a newline character is consumed. This movement
878 can be more conveniently performed by the function L</lex_read_to>,
879 which handles newlines appropriately.
881 Interpretation of the buffer's octets can be abstracted out by
882 using the slightly higher-level functions L</lex_peek_unichar> and
883 L</lex_read_unichar>.
885 =for apidoc AmxU|char *|PL_parser-E<gt>linestart
887 Points to the start of the current line inside the lexer buffer.
888 This is useful for indicating at which column an error occurred, and
889 not much else. This must be updated by any lexing code that consumes
890 a newline; the function L</lex_read_to> handles this detail.
896 =for apidoc Amx|bool|lex_bufutf8
898 Indicates whether the octets in the lexer buffer
899 (L</PL_parser-E<gt>linestr>) should be interpreted as the UTF-8 encoding
900 of Unicode characters. If not, they should be interpreted as Latin-1
901 characters. This is analogous to the C<SvUTF8> flag for scalars.
903 In UTF-8 mode, it is not guaranteed that the lexer buffer actually
904 contains valid UTF-8. Lexing code must be robust in the face of invalid
907 The actual C<SvUTF8> flag of the L</PL_parser-E<gt>linestr> scalar
908 is significant, but not the whole story regarding the input character
909 encoding. Normally, when a file is being read, the scalar contains octets
910 and its C<SvUTF8> flag is off, but the octets should be interpreted as
911 UTF-8 if the C<use utf8> pragma is in effect. During a string eval,
912 however, the scalar may have the C<SvUTF8> flag on, and in this case its
913 octets should be interpreted as UTF-8 unless the C<use bytes> pragma
914 is in effect. This logic may change in the future; use this function
915 instead of implementing the logic yourself.
921 Perl_lex_bufutf8(pTHX)
927 =for apidoc Amx|char *|lex_grow_linestr|STRLEN len
929 Reallocates the lexer buffer (L</PL_parser-E<gt>linestr>) to accommodate
930 at least I<len> octets (including terminating NUL). Returns a
931 pointer to the reallocated buffer. This is necessary before making
932 any direct modification of the buffer that would increase its length.
933 L</lex_stuff_pvn> provides a more convenient way to insert text into
936 Do not use C<SvGROW> or C<sv_grow> directly on C<PL_parser-E<gt>linestr>;
937 this function updates all of the lexer's variables that point directly
944 Perl_lex_grow_linestr(pTHX_ STRLEN len)
948 STRLEN bufend_pos, bufptr_pos, oldbufptr_pos, oldoldbufptr_pos;
949 STRLEN linestart_pos, last_uni_pos, last_lop_pos, re_eval_start_pos;
950 linestr = PL_parser->linestr;
951 buf = SvPVX(linestr);
952 if (len <= SvLEN(linestr))
954 bufend_pos = PL_parser->bufend - buf;
955 bufptr_pos = PL_parser->bufptr - buf;
956 oldbufptr_pos = PL_parser->oldbufptr - buf;
957 oldoldbufptr_pos = PL_parser->oldoldbufptr - buf;
958 linestart_pos = PL_parser->linestart - buf;
959 last_uni_pos = PL_parser->last_uni ? PL_parser->last_uni - buf : 0;
960 last_lop_pos = PL_parser->last_lop ? PL_parser->last_lop - buf : 0;
961 re_eval_start_pos = PL_parser->lex_shared->re_eval_start ?
962 PL_parser->lex_shared->re_eval_start - buf : 0;
964 buf = sv_grow(linestr, len);
966 PL_parser->bufend = buf + bufend_pos;
967 PL_parser->bufptr = buf + bufptr_pos;
968 PL_parser->oldbufptr = buf + oldbufptr_pos;
969 PL_parser->oldoldbufptr = buf + oldoldbufptr_pos;
970 PL_parser->linestart = buf + linestart_pos;
971 if (PL_parser->last_uni)
972 PL_parser->last_uni = buf + last_uni_pos;
973 if (PL_parser->last_lop)
974 PL_parser->last_lop = buf + last_lop_pos;
975 if (PL_parser->lex_shared->re_eval_start)
976 PL_parser->lex_shared->re_eval_start = buf + re_eval_start_pos;
981 =for apidoc Amx|void|lex_stuff_pvn|const char *pv|STRLEN len|U32 flags
983 Insert characters into the lexer buffer (L</PL_parser-E<gt>linestr>),
984 immediately after the current lexing point (L</PL_parser-E<gt>bufptr>),
985 reallocating the buffer if necessary. This means that lexing code that
986 runs later will see the characters as if they had appeared in the input.
987 It is not recommended to do this as part of normal parsing, and most
988 uses of this facility run the risk of the inserted characters being
989 interpreted in an unintended manner.
991 The string to be inserted is represented by I<len> octets starting
992 at I<pv>. These octets are interpreted as either UTF-8 or Latin-1,
993 according to whether the C<LEX_STUFF_UTF8> flag is set in I<flags>.
994 The characters are recoded for the lexer buffer, according to how the
995 buffer is currently being interpreted (L</lex_bufutf8>). If a string
996 to be inserted is available as a Perl scalar, the L</lex_stuff_sv>
997 function is more convenient.
1003 Perl_lex_stuff_pvn(pTHX_ const char *pv, STRLEN len, U32 flags)
1007 PERL_ARGS_ASSERT_LEX_STUFF_PVN;
1008 if (flags & ~(LEX_STUFF_UTF8))
1009 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_stuff_pvn");
1011 if (flags & LEX_STUFF_UTF8) {
1014 STRLEN highhalf = 0; /* Count of variants */
1015 const char *p, *e = pv+len;
1016 for (p = pv; p != e; p++) {
1017 if (! UTF8_IS_INVARIANT(*p)) {
1023 lex_grow_linestr(SvCUR(PL_parser->linestr)+1+len+highhalf);
1024 bufptr = PL_parser->bufptr;
1025 Move(bufptr, bufptr+len+highhalf, PL_parser->bufend+1-bufptr, char);
1026 SvCUR_set(PL_parser->linestr,
1027 SvCUR(PL_parser->linestr) + len+highhalf);
1028 PL_parser->bufend += len+highhalf;
1029 for (p = pv; p != e; p++) {
1031 if (! UTF8_IS_INVARIANT(c)) {
1032 *bufptr++ = UTF8_TWO_BYTE_HI(c);
1033 *bufptr++ = UTF8_TWO_BYTE_LO(c);
1035 *bufptr++ = (char)c;
1040 if (flags & LEX_STUFF_UTF8) {
1041 STRLEN highhalf = 0;
1042 const char *p, *e = pv+len;
1043 for (p = pv; p != e; p++) {
1045 if (UTF8_IS_ABOVE_LATIN1(c)) {
1046 Perl_croak(aTHX_ "Lexing code attempted to stuff "
1047 "non-Latin-1 character into Latin-1 input");
1048 } else if (UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(p, e)) {
1051 } else if (! UTF8_IS_INVARIANT(c)) {
1052 /* malformed UTF-8 */
1054 SAVESPTR(PL_warnhook);
1055 PL_warnhook = PERL_WARNHOOK_FATAL;
1056 utf8n_to_uvuni((U8*)p, e-p, NULL, 0);
1062 lex_grow_linestr(SvCUR(PL_parser->linestr)+1+len-highhalf);
1063 bufptr = PL_parser->bufptr;
1064 Move(bufptr, bufptr+len-highhalf, PL_parser->bufend+1-bufptr, char);
1065 SvCUR_set(PL_parser->linestr,
1066 SvCUR(PL_parser->linestr) + len-highhalf);
1067 PL_parser->bufend += len-highhalf;
1070 if (UTF8_IS_INVARIANT(*p)) {
1076 *bufptr++ = TWO_BYTE_UTF8_TO_UNI(*p, *(p+1));
1082 lex_grow_linestr(SvCUR(PL_parser->linestr)+1+len);
1083 bufptr = PL_parser->bufptr;
1084 Move(bufptr, bufptr+len, PL_parser->bufend+1-bufptr, char);
1085 SvCUR_set(PL_parser->linestr, SvCUR(PL_parser->linestr) + len);
1086 PL_parser->bufend += len;
1087 Copy(pv, bufptr, len, char);
1093 =for apidoc Amx|void|lex_stuff_pv|const char *pv|U32 flags
1095 Insert characters into the lexer buffer (L</PL_parser-E<gt>linestr>),
1096 immediately after the current lexing point (L</PL_parser-E<gt>bufptr>),
1097 reallocating the buffer if necessary. This means that lexing code that
1098 runs later will see the characters as if they had appeared in the input.
1099 It is not recommended to do this as part of normal parsing, and most
1100 uses of this facility run the risk of the inserted characters being
1101 interpreted in an unintended manner.
1103 The string to be inserted is represented by octets starting at I<pv>
1104 and continuing to the first nul. These octets are interpreted as either
1105 UTF-8 or Latin-1, according to whether the C<LEX_STUFF_UTF8> flag is set
1106 in I<flags>. The characters are recoded for the lexer buffer, according
1107 to how the buffer is currently being interpreted (L</lex_bufutf8>).
1108 If it is not convenient to nul-terminate a string to be inserted, the
1109 L</lex_stuff_pvn> function is more appropriate.
1115 Perl_lex_stuff_pv(pTHX_ const char *pv, U32 flags)
1117 PERL_ARGS_ASSERT_LEX_STUFF_PV;
1118 lex_stuff_pvn(pv, strlen(pv), flags);
1122 =for apidoc Amx|void|lex_stuff_sv|SV *sv|U32 flags
1124 Insert characters into the lexer buffer (L</PL_parser-E<gt>linestr>),
1125 immediately after the current lexing point (L</PL_parser-E<gt>bufptr>),
1126 reallocating the buffer if necessary. This means that lexing code that
1127 runs later will see the characters as if they had appeared in the input.
1128 It is not recommended to do this as part of normal parsing, and most
1129 uses of this facility run the risk of the inserted characters being
1130 interpreted in an unintended manner.
1132 The string to be inserted is the string value of I<sv>. The characters
1133 are recoded for the lexer buffer, according to how the buffer is currently
1134 being interpreted (L</lex_bufutf8>). If a string to be inserted is
1135 not already a Perl scalar, the L</lex_stuff_pvn> function avoids the
1136 need to construct a scalar.
1142 Perl_lex_stuff_sv(pTHX_ SV *sv, U32 flags)
1146 PERL_ARGS_ASSERT_LEX_STUFF_SV;
1148 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_stuff_sv");
1150 lex_stuff_pvn(pv, len, flags | (SvUTF8(sv) ? LEX_STUFF_UTF8 : 0));
1154 =for apidoc Amx|void|lex_unstuff|char *ptr
1156 Discards text about to be lexed, from L</PL_parser-E<gt>bufptr> up to
1157 I<ptr>. Text following I<ptr> will be moved, and the buffer shortened.
1158 This hides the discarded text from any lexing code that runs later,
1159 as if the text had never appeared.
1161 This is not the normal way to consume lexed text. For that, use
1168 Perl_lex_unstuff(pTHX_ char *ptr)
1172 PERL_ARGS_ASSERT_LEX_UNSTUFF;
1173 buf = PL_parser->bufptr;
1175 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_unstuff");
1178 bufend = PL_parser->bufend;
1180 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_unstuff");
1181 unstuff_len = ptr - buf;
1182 Move(ptr, buf, bufend+1-ptr, char);
1183 SvCUR_set(PL_parser->linestr, SvCUR(PL_parser->linestr) - unstuff_len);
1184 PL_parser->bufend = bufend - unstuff_len;
1188 =for apidoc Amx|void|lex_read_to|char *ptr
1190 Consume text in the lexer buffer, from L</PL_parser-E<gt>bufptr> up
1191 to I<ptr>. This advances L</PL_parser-E<gt>bufptr> to match I<ptr>,
1192 performing the correct bookkeeping whenever a newline character is passed.
1193 This is the normal way to consume lexed text.
1195 Interpretation of the buffer's octets can be abstracted out by
1196 using the slightly higher-level functions L</lex_peek_unichar> and
1197 L</lex_read_unichar>.
1203 Perl_lex_read_to(pTHX_ char *ptr)
1206 PERL_ARGS_ASSERT_LEX_READ_TO;
1207 s = PL_parser->bufptr;
1208 if (ptr < s || ptr > PL_parser->bufend)
1209 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_read_to");
1210 for (; s != ptr; s++)
1212 COPLINE_INC_WITH_HERELINES;
1213 PL_parser->linestart = s+1;
1215 PL_parser->bufptr = ptr;
1219 =for apidoc Amx|void|lex_discard_to|char *ptr
1221 Discards the first part of the L</PL_parser-E<gt>linestr> buffer,
1222 up to I<ptr>. The remaining content of the buffer will be moved, and
1223 all pointers into the buffer updated appropriately. I<ptr> must not
1224 be later in the buffer than the position of L</PL_parser-E<gt>bufptr>:
1225 it is not permitted to discard text that has yet to be lexed.
1227 Normally it is not necessarily to do this directly, because it suffices to
1228 use the implicit discarding behaviour of L</lex_next_chunk> and things
1229 based on it. However, if a token stretches across multiple lines,
1230 and the lexing code has kept multiple lines of text in the buffer for
1231 that purpose, then after completion of the token it would be wise to
1232 explicitly discard the now-unneeded earlier lines, to avoid future
1233 multi-line tokens growing the buffer without bound.
1239 Perl_lex_discard_to(pTHX_ char *ptr)
1243 PERL_ARGS_ASSERT_LEX_DISCARD_TO;
1244 buf = SvPVX(PL_parser->linestr);
1246 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_discard_to");
1249 if (ptr > PL_parser->bufptr)
1250 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_discard_to");
1251 discard_len = ptr - buf;
1252 if (PL_parser->oldbufptr < ptr)
1253 PL_parser->oldbufptr = ptr;
1254 if (PL_parser->oldoldbufptr < ptr)
1255 PL_parser->oldoldbufptr = ptr;
1256 if (PL_parser->last_uni && PL_parser->last_uni < ptr)
1257 PL_parser->last_uni = NULL;
1258 if (PL_parser->last_lop && PL_parser->last_lop < ptr)
1259 PL_parser->last_lop = NULL;
1260 Move(ptr, buf, PL_parser->bufend+1-ptr, char);
1261 SvCUR_set(PL_parser->linestr, SvCUR(PL_parser->linestr) - discard_len);
1262 PL_parser->bufend -= discard_len;
1263 PL_parser->bufptr -= discard_len;
1264 PL_parser->oldbufptr -= discard_len;
1265 PL_parser->oldoldbufptr -= discard_len;
1266 if (PL_parser->last_uni)
1267 PL_parser->last_uni -= discard_len;
1268 if (PL_parser->last_lop)
1269 PL_parser->last_lop -= discard_len;
1273 =for apidoc Amx|bool|lex_next_chunk|U32 flags
1275 Reads in the next chunk of text to be lexed, appending it to
1276 L</PL_parser-E<gt>linestr>. This should be called when lexing code has
1277 looked to the end of the current chunk and wants to know more. It is
1278 usual, but not necessary, for lexing to have consumed the entirety of
1279 the current chunk at this time.
1281 If L</PL_parser-E<gt>bufptr> is pointing to the very end of the current
1282 chunk (i.e., the current chunk has been entirely consumed), normally the
1283 current chunk will be discarded at the same time that the new chunk is
1284 read in. If I<flags> includes C<LEX_KEEP_PREVIOUS>, the current chunk
1285 will not be discarded. If the current chunk has not been entirely
1286 consumed, then it will not be discarded regardless of the flag.
1288 Returns true if some new text was added to the buffer, or false if the
1289 buffer has reached the end of the input text.
1294 #define LEX_FAKE_EOF 0x80000000
1295 #define LEX_NO_TERM 0x40000000
1298 Perl_lex_next_chunk(pTHX_ U32 flags)
1302 STRLEN old_bufend_pos, new_bufend_pos;
1303 STRLEN bufptr_pos, oldbufptr_pos, oldoldbufptr_pos;
1304 STRLEN linestart_pos, last_uni_pos, last_lop_pos;
1305 bool got_some_for_debugger = 0;
1307 if (flags & ~(LEX_KEEP_PREVIOUS|LEX_FAKE_EOF|LEX_NO_TERM))
1308 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_next_chunk");
1309 linestr = PL_parser->linestr;
1310 buf = SvPVX(linestr);
1311 if (!(flags & LEX_KEEP_PREVIOUS) &&
1312 PL_parser->bufptr == PL_parser->bufend) {
1313 old_bufend_pos = bufptr_pos = oldbufptr_pos = oldoldbufptr_pos = 0;
1315 if (PL_parser->last_uni != PL_parser->bufend)
1316 PL_parser->last_uni = NULL;
1317 if (PL_parser->last_lop != PL_parser->bufend)
1318 PL_parser->last_lop = NULL;
1319 last_uni_pos = last_lop_pos = 0;
1323 old_bufend_pos = PL_parser->bufend - buf;
1324 bufptr_pos = PL_parser->bufptr - buf;
1325 oldbufptr_pos = PL_parser->oldbufptr - buf;
1326 oldoldbufptr_pos = PL_parser->oldoldbufptr - buf;
1327 linestart_pos = PL_parser->linestart - buf;
1328 last_uni_pos = PL_parser->last_uni ? PL_parser->last_uni - buf : 0;
1329 last_lop_pos = PL_parser->last_lop ? PL_parser->last_lop - buf : 0;
1331 if (flags & LEX_FAKE_EOF) {
1333 } else if (!PL_parser->rsfp && !PL_parser->filtered) {
1335 } else if (filter_gets(linestr, old_bufend_pos)) {
1337 got_some_for_debugger = 1;
1338 } else if (flags & LEX_NO_TERM) {
1341 if (!SvPOK(linestr)) /* can get undefined by filter_gets */
1342 sv_setpvs(linestr, "");
1344 /* End of real input. Close filehandle (unless it was STDIN),
1345 * then add implicit termination.
1347 if (PL_parser->lex_flags & LEX_DONT_CLOSE_RSFP)
1348 PerlIO_clearerr(PL_parser->rsfp);
1349 else if (PL_parser->rsfp)
1350 (void)PerlIO_close(PL_parser->rsfp);
1351 PL_parser->rsfp = NULL;
1352 PL_parser->in_pod = PL_parser->filtered = 0;
1354 if (PL_madskills && !PL_in_eval && (PL_minus_p || PL_minus_n))
1357 if (!PL_in_eval && PL_minus_p) {
1359 /*{*/";}continue{print or die qq(-p destination: $!\\n);}");
1360 PL_minus_n = PL_minus_p = 0;
1361 } else if (!PL_in_eval && PL_minus_n) {
1362 sv_catpvs(linestr, /*{*/";}");
1365 sv_catpvs(linestr, ";");
1368 buf = SvPVX(linestr);
1369 new_bufend_pos = SvCUR(linestr);
1370 PL_parser->bufend = buf + new_bufend_pos;
1371 PL_parser->bufptr = buf + bufptr_pos;
1372 PL_parser->oldbufptr = buf + oldbufptr_pos;
1373 PL_parser->oldoldbufptr = buf + oldoldbufptr_pos;
1374 PL_parser->linestart = buf + linestart_pos;
1375 if (PL_parser->last_uni)
1376 PL_parser->last_uni = buf + last_uni_pos;
1377 if (PL_parser->last_lop)
1378 PL_parser->last_lop = buf + last_lop_pos;
1379 if (got_some_for_debugger && (PERLDB_LINE || PERLDB_SAVESRC) &&
1380 PL_curstash != PL_debstash) {
1381 /* debugger active and we're not compiling the debugger code,
1382 * so store the line into the debugger's array of lines
1384 update_debugger_info(NULL, buf+old_bufend_pos,
1385 new_bufend_pos-old_bufend_pos);
1391 =for apidoc Amx|I32|lex_peek_unichar|U32 flags
1393 Looks ahead one (Unicode) character in the text currently being lexed.
1394 Returns the codepoint (unsigned integer value) of the next character,
1395 or -1 if lexing has reached the end of the input text. To consume the
1396 peeked character, use L</lex_read_unichar>.
1398 If the next character is in (or extends into) the next chunk of input
1399 text, the next chunk will be read in. Normally the current chunk will be
1400 discarded at the same time, but if I<flags> includes C<LEX_KEEP_PREVIOUS>
1401 then the current chunk will not be discarded.
1403 If the input is being interpreted as UTF-8 and a UTF-8 encoding error
1404 is encountered, an exception is generated.
1410 Perl_lex_peek_unichar(pTHX_ U32 flags)
1414 if (flags & ~(LEX_KEEP_PREVIOUS))
1415 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_peek_unichar");
1416 s = PL_parser->bufptr;
1417 bufend = PL_parser->bufend;
1423 if (!lex_next_chunk(flags))
1425 s = PL_parser->bufptr;
1426 bufend = PL_parser->bufend;
1429 if (UTF8_IS_INVARIANT(head))
1431 if (UTF8_IS_START(head)) {
1432 len = UTF8SKIP(&head);
1433 while ((STRLEN)(bufend-s) < len) {
1434 if (!lex_next_chunk(flags | LEX_KEEP_PREVIOUS))
1436 s = PL_parser->bufptr;
1437 bufend = PL_parser->bufend;
1440 unichar = utf8n_to_uvuni((U8*)s, bufend-s, &retlen, UTF8_CHECK_ONLY);
1441 if (retlen == (STRLEN)-1) {
1442 /* malformed UTF-8 */
1444 SAVESPTR(PL_warnhook);
1445 PL_warnhook = PERL_WARNHOOK_FATAL;
1446 utf8n_to_uvuni((U8*)s, bufend-s, NULL, 0);
1452 if (!lex_next_chunk(flags))
1454 s = PL_parser->bufptr;
1461 =for apidoc Amx|I32|lex_read_unichar|U32 flags
1463 Reads the next (Unicode) character in the text currently being lexed.
1464 Returns the codepoint (unsigned integer value) of the character read,
1465 and moves L</PL_parser-E<gt>bufptr> past the character, or returns -1
1466 if lexing has reached the end of the input text. To non-destructively
1467 examine the next character, use L</lex_peek_unichar> instead.
1469 If the next character is in (or extends into) the next chunk of input
1470 text, the next chunk will be read in. Normally the current chunk will be
1471 discarded at the same time, but if I<flags> includes C<LEX_KEEP_PREVIOUS>
1472 then the current chunk will not be discarded.
1474 If the input is being interpreted as UTF-8 and a UTF-8 encoding error
1475 is encountered, an exception is generated.
1481 Perl_lex_read_unichar(pTHX_ U32 flags)
1484 if (flags & ~(LEX_KEEP_PREVIOUS))
1485 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_read_unichar");
1486 c = lex_peek_unichar(flags);
1489 COPLINE_INC_WITH_HERELINES;
1491 PL_parser->bufptr += UTF8SKIP(PL_parser->bufptr);
1493 ++(PL_parser->bufptr);
1499 =for apidoc Amx|void|lex_read_space|U32 flags
1501 Reads optional spaces, in Perl style, in the text currently being
1502 lexed. The spaces may include ordinary whitespace characters and
1503 Perl-style comments. C<#line> directives are processed if encountered.
1504 L</PL_parser-E<gt>bufptr> is moved past the spaces, so that it points
1505 at a non-space character (or the end of the input text).
1507 If spaces extend into the next chunk of input text, the next chunk will
1508 be read in. Normally the current chunk will be discarded at the same
1509 time, but if I<flags> includes C<LEX_KEEP_PREVIOUS> then the current
1510 chunk will not be discarded.
1515 #define LEX_NO_NEXT_CHUNK 0x80000000
1518 Perl_lex_read_space(pTHX_ U32 flags)
1521 bool need_incline = 0;
1522 if (flags & ~(LEX_KEEP_PREVIOUS|LEX_NO_NEXT_CHUNK))
1523 Perl_croak(aTHX_ "Lexing code internal error (%s)", "lex_read_space");
1526 sv_free(PL_skipwhite);
1527 PL_skipwhite = NULL;
1530 PL_skipwhite = newSVpvs("");
1531 #endif /* PERL_MAD */
1532 s = PL_parser->bufptr;
1533 bufend = PL_parser->bufend;
1539 } while (!(c == '\n' || (c == 0 && s == bufend)));
1540 } else if (c == '\n') {
1542 PL_parser->linestart = s;
1547 } else if (isSPACE(c)) {
1549 } else if (c == 0 && s == bufend) {
1553 sv_catpvn(PL_skipwhite, PL_parser->bufptr, s-PL_parser->bufptr);
1554 #endif /* PERL_MAD */
1555 if (flags & LEX_NO_NEXT_CHUNK)
1557 PL_parser->bufptr = s;
1558 COPLINE_INC_WITH_HERELINES;
1559 got_more = lex_next_chunk(flags);
1560 CopLINE_dec(PL_curcop);
1561 s = PL_parser->bufptr;
1562 bufend = PL_parser->bufend;
1565 if (need_incline && PL_parser->rsfp) {
1575 sv_catpvn(PL_skipwhite, PL_parser->bufptr, s-PL_parser->bufptr);
1576 #endif /* PERL_MAD */
1577 PL_parser->bufptr = s;
1582 * This subroutine has nothing to do with tilting, whether at windmills
1583 * or pinball tables. Its name is short for "increment line". It
1584 * increments the current line number in CopLINE(PL_curcop) and checks
1585 * to see whether the line starts with a comment of the form
1586 * # line 500 "foo.pm"
1587 * If so, it sets the current line number and file to the values in the comment.
1591 S_incline(pTHX_ const char *s)
1599 PERL_ARGS_ASSERT_INCLINE;
1601 COPLINE_INC_WITH_HERELINES;
1602 if (!PL_rsfp && !PL_parser->filtered && PL_lex_state == LEX_NORMAL
1603 && s+1 == PL_bufend && *s == ';') {
1604 /* fake newline in string eval */
1605 CopLINE_dec(PL_curcop);
1610 while (SPACE_OR_TAB(*s))
1612 if (strnEQ(s, "line", 4))
1616 if (SPACE_OR_TAB(*s))
1620 while (SPACE_OR_TAB(*s))
1628 if (!SPACE_OR_TAB(*s) && *s != '\r' && *s != '\n' && *s != '\0')
1630 while (SPACE_OR_TAB(*s))
1632 if (*s == '"' && (t = strchr(s+1, '"'))) {
1638 while (!isSPACE(*t))
1642 while (SPACE_OR_TAB(*e) || *e == '\r' || *e == '\f')
1644 if (*e != '\n' && *e != '\0')
1645 return; /* false alarm */
1647 line_num = atoi(n)-1;
1650 const STRLEN len = t - s;
1651 SV *const temp_sv = CopFILESV(PL_curcop);
1656 cf = SvPVX(temp_sv);
1657 tmplen = SvCUR(temp_sv);
1663 if (!PL_rsfp && !PL_parser->filtered) {
1664 /* must copy *{"::_<(eval N)[oldfilename:L]"}
1665 * to *{"::_<newfilename"} */
1666 /* However, the long form of evals is only turned on by the
1667 debugger - usually they're "(eval %lu)" */
1671 STRLEN tmplen2 = len;
1672 if (tmplen + 2 <= sizeof smallbuf)
1675 Newx(tmpbuf, tmplen + 2, char);
1678 memcpy(tmpbuf + 2, cf, tmplen);
1680 gvp = (GV**)hv_fetch(PL_defstash, tmpbuf, tmplen, FALSE);
1685 if (tmplen2 + 2 <= sizeof smallbuf)
1688 Newx(tmpbuf2, tmplen2 + 2, char);
1690 if (tmpbuf2 != smallbuf || tmpbuf != smallbuf) {
1691 /* Either they malloc'd it, or we malloc'd it,
1692 so no prefix is present in ours. */
1697 memcpy(tmpbuf2 + 2, s, tmplen2);
1700 gv2 = *(GV**)hv_fetch(PL_defstash, tmpbuf2, tmplen2, TRUE);
1702 gv_init(gv2, PL_defstash, tmpbuf2, tmplen2, FALSE);
1703 /* adjust ${"::_<newfilename"} to store the new file name */
1704 GvSV(gv2) = newSVpvn(tmpbuf2 + 2, tmplen2 - 2);
1705 /* The line number may differ. If that is the case,
1706 alias the saved lines that are in the array.
1707 Otherwise alias the whole array. */
1708 if (CopLINE(PL_curcop) == line_num) {
1709 GvHV(gv2) = MUTABLE_HV(SvREFCNT_inc(GvHV(*gvp)));
1710 GvAV(gv2) = MUTABLE_AV(SvREFCNT_inc(GvAV(*gvp)));
1712 else if (GvAV(*gvp)) {
1713 AV * const av = GvAV(*gvp);
1714 const I32 start = CopLINE(PL_curcop)+1;
1715 I32 items = AvFILLp(av) - start;
1717 AV * const av2 = GvAVn(gv2);
1718 SV **svp = AvARRAY(av) + start;
1719 I32 l = (I32)line_num+1;
1721 av_store(av2, l++, SvREFCNT_inc(*svp++));
1726 if (tmpbuf2 != smallbuf) Safefree(tmpbuf2);
1728 if (tmpbuf != smallbuf) Safefree(tmpbuf);
1730 CopFILE_free(PL_curcop);
1731 CopFILE_setn(PL_curcop, s, len);
1733 CopLINE_set(PL_curcop, line_num);
1737 /* skip space before PL_thistoken */
1740 S_skipspace0(pTHX_ char *s)
1742 PERL_ARGS_ASSERT_SKIPSPACE0;
1749 PL_thiswhite = newSVpvs("");
1750 sv_catsv(PL_thiswhite, PL_skipwhite);
1751 sv_free(PL_skipwhite);
1754 PL_realtokenstart = s - SvPVX(PL_linestr);
1758 /* skip space after PL_thistoken */
1761 S_skipspace1(pTHX_ char *s)
1763 const char *start = s;
1764 I32 startoff = start - SvPVX(PL_linestr);
1766 PERL_ARGS_ASSERT_SKIPSPACE1;
1771 start = SvPVX(PL_linestr) + startoff;
1772 if (!PL_thistoken && PL_realtokenstart >= 0) {
1773 const char * const tstart = SvPVX(PL_linestr) + PL_realtokenstart;
1774 PL_thistoken = newSVpvn(tstart, start - tstart);
1776 PL_realtokenstart = -1;
1779 PL_nextwhite = newSVpvs("");
1780 sv_catsv(PL_nextwhite, PL_skipwhite);
1781 sv_free(PL_skipwhite);
1788 S_skipspace2(pTHX_ char *s, SV **svp)
1791 const I32 bufptroff = PL_bufptr - SvPVX(PL_linestr);
1792 const I32 startoff = s - SvPVX(PL_linestr);
1794 PERL_ARGS_ASSERT_SKIPSPACE2;
1797 PL_bufptr = SvPVX(PL_linestr) + bufptroff;
1798 if (!PL_madskills || !svp)
1800 start = SvPVX(PL_linestr) + startoff;
1801 if (!PL_thistoken && PL_realtokenstart >= 0) {
1802 char * const tstart = SvPVX(PL_linestr) + PL_realtokenstart;
1803 PL_thistoken = newSVpvn(tstart, start - tstart);
1804 PL_realtokenstart = -1;
1808 *svp = newSVpvs("");
1809 sv_setsv(*svp, PL_skipwhite);
1810 sv_free(PL_skipwhite);
1819 S_update_debugger_info(pTHX_ SV *orig_sv, const char *const buf, STRLEN len)
1821 AV *av = CopFILEAVx(PL_curcop);
1823 SV * const sv = newSV_type(SVt_PVMG);
1825 sv_setsv(sv, orig_sv);
1827 sv_setpvn(sv, buf, len);
1830 av_store(av, (I32)CopLINE(PL_curcop), sv);
1836 * Called to gobble the appropriate amount and type of whitespace.
1837 * Skips comments as well.
1841 S_skipspace(pTHX_ char *s)
1845 #endif /* PERL_MAD */
1846 PERL_ARGS_ASSERT_SKIPSPACE;
1849 sv_free(PL_skipwhite);
1850 PL_skipwhite = NULL;
1852 #endif /* PERL_MAD */
1853 if (PL_lex_formbrack && PL_lex_brackets <= PL_lex_formbrack) {
1854 while (s < PL_bufend && SPACE_OR_TAB(*s))
1857 STRLEN bufptr_pos = PL_bufptr - SvPVX(PL_linestr);
1859 lex_read_space(LEX_KEEP_PREVIOUS |
1860 (PL_sublex_info.sub_inwhat || PL_lex_state == LEX_FORMLINE ?
1861 LEX_NO_NEXT_CHUNK : 0));
1863 PL_bufptr = SvPVX(PL_linestr) + bufptr_pos;
1864 if (PL_linestart > PL_bufptr)
1865 PL_bufptr = PL_linestart;
1870 PL_skipwhite = newSVpvn(start, s-start);
1871 #endif /* PERL_MAD */
1877 * Check the unary operators to ensure there's no ambiguity in how they're
1878 * used. An ambiguous piece of code would be:
1880 * This doesn't mean rand() + 5. Because rand() is a unary operator,
1881 * the +5 is its argument.
1891 if (PL_oldoldbufptr != PL_last_uni)
1893 while (isSPACE(*PL_last_uni))
1896 while (isWORDCHAR_lazy_if(s,UTF) || *s == '-')
1898 if ((t = strchr(s, '(')) && t < PL_bufptr)
1901 Perl_ck_warner_d(aTHX_ packWARN(WARN_AMBIGUOUS),
1902 "Warning: Use of \"%.*s\" without parentheses is ambiguous",
1903 (int)(s - PL_last_uni), PL_last_uni);
1907 * LOP : macro to build a list operator. Its behaviour has been replaced
1908 * with a subroutine, S_lop() for which LOP is just another name.
1911 #define LOP(f,x) return lop(f,x,s)
1915 * Build a list operator (or something that might be one). The rules:
1916 * - if we have a next token, then it's a list operator [why?]
1917 * - if the next thing is an opening paren, then it's a function
1918 * - else it's a list operator
1922 S_lop(pTHX_ I32 f, int x, char *s)
1926 PERL_ARGS_ASSERT_LOP;
1932 PL_last_lop = PL_oldbufptr;
1933 PL_last_lop_op = (OPCODE)f;
1942 return REPORT(FUNC);
1945 return REPORT(FUNC);
1948 if (!PL_lex_allbrackets && PL_lex_fakeeof > LEX_FAKEEOF_LOWLOGIC)
1949 PL_lex_fakeeof = LEX_FAKEEOF_LOWLOGIC;
1950 return REPORT(LSTOP);
1957 * Sets up for an eventual force_next(). start_force(0) basically does
1958 * an unshift, while start_force(-1) does a push. yylex removes items
1963 S_start_force(pTHX_ int where)
1967 if (where < 0) /* so people can duplicate start_force(PL_curforce) */
1968 where = PL_lasttoke;
1969 assert(PL_curforce < 0 || PL_curforce == where);
1970 if (PL_curforce != where) {
1971 for (i = PL_lasttoke; i > where; --i) {
1972 PL_nexttoke[i] = PL_nexttoke[i-1];
1976 if (PL_curforce < 0) /* in case of duplicate start_force() */
1977 Zero(&PL_nexttoke[where], 1, NEXTTOKE);
1978 PL_curforce = where;
1981 curmad('^', newSVpvs(""));
1982 CURMAD('_', PL_nextwhite);
1987 S_curmad(pTHX_ char slot, SV *sv)
1993 if (PL_curforce < 0)
1994 where = &PL_thismad;
1996 where = &PL_nexttoke[PL_curforce].next_mad;
2002 if (UTF && is_utf8_string((U8*)SvPVX(sv), SvCUR(sv)))
2004 else if (PL_encoding) {
2005 sv_recode_to_utf8(sv, PL_encoding);
2010 /* keep a slot open for the head of the list? */
2011 if (slot != '_' && *where && (*where)->mad_key == '^') {
2012 (*where)->mad_key = slot;
2013 sv_free(MUTABLE_SV(((*where)->mad_val)));
2014 (*where)->mad_val = (void*)sv;
2017 addmad(newMADsv(slot, sv), where, 0);
2020 # define start_force(where) NOOP
2021 # define curmad(slot, sv) NOOP
2026 * When the lexer realizes it knows the next token (for instance,
2027 * it is reordering tokens for the parser) then it can call S_force_next
2028 * to know what token to return the next time the lexer is called. Caller
2029 * will need to set PL_nextval[] (or PL_nexttoke[].next_val with PERL_MAD),
2030 * and possibly PL_expect to ensure the lexer handles the token correctly.
2034 S_force_next(pTHX_ I32 type)
2039 PerlIO_printf(Perl_debug_log, "### forced token:\n");
2040 tokereport(type, &NEXTVAL_NEXTTOKE);
2044 if (PL_curforce < 0)
2045 start_force(PL_lasttoke);
2046 PL_nexttoke[PL_curforce].next_type = type;
2047 if (PL_lex_state != LEX_KNOWNEXT)
2048 PL_lex_defer = PL_lex_state;
2049 PL_lex_state = LEX_KNOWNEXT;
2050 PL_lex_expect = PL_expect;
2053 PL_nexttype[PL_nexttoke] = type;
2055 if (PL_lex_state != LEX_KNOWNEXT) {
2056 PL_lex_defer = PL_lex_state;
2057 PL_lex_expect = PL_expect;
2058 PL_lex_state = LEX_KNOWNEXT;
2066 int yyc = PL_parser->yychar;
2067 if (yyc != YYEMPTY) {
2070 NEXTVAL_NEXTTOKE = PL_parser->yylval;
2071 if (yyc == '{'/*}*/ || yyc == HASHBRACK || yyc == '['/*]*/) {
2072 PL_lex_allbrackets--;
2074 yyc |= (3<<24) | (PL_lex_brackstack[PL_lex_brackets] << 16);
2075 } else if (yyc == '('/*)*/) {
2076 PL_lex_allbrackets--;
2081 PL_parser->yychar = YYEMPTY;
2086 S_newSV_maybe_utf8(pTHX_ const char *const start, STRLEN len)
2089 SV * const sv = newSVpvn_utf8(start, len,
2092 && !is_ascii_string((const U8*)start, len)
2093 && is_utf8_string((const U8*)start, len));
2099 * When the lexer knows the next thing is a word (for instance, it has
2100 * just seen -> and it knows that the next char is a word char, then
2101 * it calls S_force_word to stick the next word into the PL_nexttoke/val
2105 * char *start : buffer position (must be within PL_linestr)
2106 * int token : PL_next* will be this type of bare word (e.g., METHOD,WORD)
2107 * int check_keyword : if true, Perl checks to make sure the word isn't
2108 * a keyword (do this if the word is a label, e.g. goto FOO)
2109 * int allow_pack : if true, : characters will also be allowed (require,
2110 * use, etc. do this)
2111 * int allow_initial_tick : used by the "sub" lexer only.
2115 S_force_word(pTHX_ char *start, int token, int check_keyword, int allow_pack)
2121 PERL_ARGS_ASSERT_FORCE_WORD;
2123 start = SKIPSPACE1(start);
2125 if (isIDFIRST_lazy_if(s,UTF) ||
2126 (allow_pack && *s == ':') )
2128 s = scan_word(s, PL_tokenbuf, sizeof PL_tokenbuf, allow_pack, &len);
2129 if (check_keyword) {
2130 char *s2 = PL_tokenbuf;
2131 if (allow_pack && len > 6 && strnEQ(s2, "CORE::", 6))
2133 if (keyword(s2, len, 0))
2136 start_force(PL_curforce);
2138 curmad('X', newSVpvn(start,s-start));
2139 if (token == METHOD) {
2144 PL_expect = XOPERATOR;
2148 curmad('g', newSVpvs( "forced" ));
2149 NEXTVAL_NEXTTOKE.opval
2150 = (OP*)newSVOP(OP_CONST,0,
2151 S_newSV_maybe_utf8(aTHX_ PL_tokenbuf, len));
2152 NEXTVAL_NEXTTOKE.opval->op_private |= OPpCONST_BARE;
2160 * Called when the lexer wants $foo *foo &foo etc, but the program
2161 * text only contains the "foo" portion. The first argument is a pointer
2162 * to the "foo", and the second argument is the type symbol to prefix.
2163 * Forces the next token to be a "WORD".
2164 * Creates the symbol if it didn't already exist (via gv_fetchpv()).
2168 S_force_ident(pTHX_ const char *s, int kind)
2172 PERL_ARGS_ASSERT_FORCE_IDENT;
2175 const STRLEN len = s[1] ? strlen(s) : 1; /* s = "\"" see yylex */
2176 OP* const o = (OP*)newSVOP(OP_CONST, 0, newSVpvn_flags(s, len,
2177 UTF ? SVf_UTF8 : 0));
2178 start_force(PL_curforce);
2179 NEXTVAL_NEXTTOKE.opval = o;
2182 o->op_private = OPpCONST_ENTERED;
2183 /* XXX see note in pp_entereval() for why we forgo typo
2184 warnings if the symbol must be introduced in an eval.
2186 gv_fetchpvn_flags(s, len,
2187 (PL_in_eval ? (GV_ADDMULTI | GV_ADDINEVAL)
2188 : GV_ADD) | ( UTF ? SVf_UTF8 : 0 ),
2189 kind == '$' ? SVt_PV :
2190 kind == '@' ? SVt_PVAV :
2191 kind == '%' ? SVt_PVHV :
2199 S_force_ident_maybe_lex(pTHX_ char pit)
2201 start_force(PL_curforce);
2202 NEXTVAL_NEXTTOKE.ival = pit;
2207 Perl_str_to_version(pTHX_ SV *sv)
2212 const char *start = SvPV_const(sv,len);
2213 const char * const end = start + len;
2214 const bool utf = SvUTF8(sv) ? TRUE : FALSE;
2216 PERL_ARGS_ASSERT_STR_TO_VERSION;
2218 while (start < end) {
2222 n = utf8n_to_uvchr((U8*)start, len, &skip, 0);
2227 retval += ((NV)n)/nshift;
2236 * Forces the next token to be a version number.
2237 * If the next token appears to be an invalid version number, (e.g. "v2b"),
2238 * and if "guessing" is TRUE, then no new token is created (and the caller
2239 * must use an alternative parsing method).
2243 S_force_version(pTHX_ char *s, int guessing)
2249 I32 startoff = s - SvPVX(PL_linestr);
2252 PERL_ARGS_ASSERT_FORCE_VERSION;
2260 while (isDIGIT(*d) || *d == '_' || *d == '.')
2264 start_force(PL_curforce);
2265 curmad('X', newSVpvn(s,d-s));
2268 if (*d == ';' || isSPACE(*d) || *d == '{' || *d == '}' || !*d) {
2270 #ifdef USE_LOCALE_NUMERIC
2271 char *loc = savepv(setlocale(LC_NUMERIC, NULL));
2272 setlocale(LC_NUMERIC, "C");
2274 s = scan_num(s, &pl_yylval);
2275 #ifdef USE_LOCALE_NUMERIC
2276 setlocale(LC_NUMERIC, loc);
2279 version = pl_yylval.opval;
2280 ver = cSVOPx(version)->op_sv;
2281 if (SvPOK(ver) && !SvNIOK(ver)) {
2282 SvUPGRADE(ver, SVt_PVNV);
2283 SvNV_set(ver, str_to_version(ver));
2284 SvNOK_on(ver); /* hint that it is a version */
2287 else if (guessing) {
2290 sv_free(PL_nextwhite); /* let next token collect whitespace */
2292 s = SvPVX(PL_linestr) + startoff;
2300 if (PL_madskills && !version) {
2301 sv_free(PL_nextwhite); /* let next token collect whitespace */
2303 s = SvPVX(PL_linestr) + startoff;
2306 /* NOTE: The parser sees the package name and the VERSION swapped */
2307 start_force(PL_curforce);
2308 NEXTVAL_NEXTTOKE.opval = version;
2315 * S_force_strict_version
2316 * Forces the next token to be a version number using strict syntax rules.
2320 S_force_strict_version(pTHX_ char *s)
2325 I32 startoff = s - SvPVX(PL_linestr);
2327 const char *errstr = NULL;
2329 PERL_ARGS_ASSERT_FORCE_STRICT_VERSION;
2331 while (isSPACE(*s)) /* leading whitespace */
2334 if (is_STRICT_VERSION(s,&errstr)) {
2336 s = (char *)scan_version(s, ver, 0);
2337 version = newSVOP(OP_CONST, 0, ver);
2339 else if ( (*s != ';' && *s != '{' && *s != '}' ) &&
2340 (s = SKIPSPACE1(s), (*s != ';' && *s != '{' && *s != '}' )))
2344 yyerror(errstr); /* version required */
2349 if (PL_madskills && !version) {
2350 sv_free(PL_nextwhite); /* let next token collect whitespace */
2352 s = SvPVX(PL_linestr) + startoff;
2355 /* NOTE: The parser sees the package name and the VERSION swapped */
2356 start_force(PL_curforce);
2357 NEXTVAL_NEXTTOKE.opval = version;
2365 * Tokenize a quoted string passed in as an SV. It finds the next
2366 * chunk, up to end of string or a backslash. It may make a new
2367 * SV containing that chunk (if HINT_NEW_STRING is on). It also
2372 S_tokeq(pTHX_ SV *sv)
2381 PERL_ARGS_ASSERT_TOKEQ;
2386 s = SvPV_force(sv, len);
2387 if (SvTYPE(sv) >= SVt_PVIV && SvIVX(sv) == -1)
2390 /* This is relying on the SV being "well formed" with a trailing '\0' */
2391 while (s < send && !(*s == '\\' && s[1] == '\\'))
2396 if ( PL_hints & HINT_NEW_STRING ) {
2397 pv = newSVpvn_flags(SvPVX_const(pv), len, SVs_TEMP | SvUTF8(sv));
2401 if (s + 1 < send && (s[1] == '\\'))
2402 s++; /* all that, just for this */
2407 SvCUR_set(sv, d - SvPVX_const(sv));
2409 if ( PL_hints & HINT_NEW_STRING )
2410 return new_constant(NULL, 0, "q", sv, pv, "q", 1);
2415 * Now come three functions related to double-quote context,
2416 * S_sublex_start, S_sublex_push, and S_sublex_done. They're used when
2417 * converting things like "\u\Lgnat" into ucfirst(lc("gnat")). They
2418 * interact with PL_lex_state, and create fake ( ... ) argument lists
2419 * to handle functions and concatenation.
2423 * stringify ( const[foo] concat lcfirst ( const[bar] ) )
2428 * Assumes that pl_yylval.ival is the op we're creating (e.g. OP_LCFIRST).
2430 * Pattern matching will set PL_lex_op to the pattern-matching op to
2431 * make (we return THING if pl_yylval.ival is OP_NULL, PMFUNC otherwise).
2433 * OP_CONST and OP_READLINE are easy--just make the new op and return.
2435 * Everything else becomes a FUNC.
2437 * Sets PL_lex_state to LEX_INTERPPUSH unless (ival was OP_NULL or we
2438 * had an OP_CONST or OP_READLINE). This just sets us up for a
2439 * call to S_sublex_push().
2443 S_sublex_start(pTHX)
2446 const I32 op_type = pl_yylval.ival;
2448 if (op_type == OP_NULL) {
2449 pl_yylval.opval = PL_lex_op;
2453 if (op_type == OP_CONST || op_type == OP_READLINE) {
2454 SV *sv = tokeq(PL_lex_stuff);
2456 if (SvTYPE(sv) == SVt_PVIV) {
2457 /* Overloaded constants, nothing fancy: Convert to SVt_PV: */
2459 const char * const p = SvPV_const(sv, len);
2460 SV * const nsv = newSVpvn_flags(p, len, SvUTF8(sv));
2464 pl_yylval.opval = (OP*)newSVOP(op_type, 0, sv);
2465 PL_lex_stuff = NULL;
2466 /* Allow <FH> // "foo" */
2467 if (op_type == OP_READLINE)
2468 PL_expect = XTERMORDORDOR;
2471 else if (op_type == OP_BACKTICK && PL_lex_op) {
2472 /* readpipe() vas overriden */
2473 cSVOPx(cLISTOPx(cUNOPx(PL_lex_op)->op_first)->op_first->op_sibling)->op_sv = tokeq(PL_lex_stuff);
2474 pl_yylval.opval = PL_lex_op;
2476 PL_lex_stuff = NULL;
2480 PL_sublex_info.super_state = PL_lex_state;
2481 PL_sublex_info.sub_inwhat = (U16)op_type;
2482 PL_sublex_info.sub_op = PL_lex_op;
2483 PL_lex_state = LEX_INTERPPUSH;
2487 pl_yylval.opval = PL_lex_op;
2497 * Create a new scope to save the lexing state. The scope will be
2498 * ended in S_sublex_done. Returns a '(', starting the function arguments
2499 * to the uc, lc, etc. found before.
2500 * Sets PL_lex_state to LEX_INTERPCONCAT.
2510 PL_lex_state = PL_sublex_info.super_state;
2511 SAVEBOOL(PL_lex_dojoin);
2512 SAVEI32(PL_lex_brackets);
2513 SAVEI32(PL_lex_allbrackets);
2514 SAVEI32(PL_lex_formbrack);
2515 SAVEI8(PL_lex_fakeeof);
2516 SAVEI32(PL_lex_casemods);
2517 SAVEI32(PL_lex_starts);
2518 SAVEI8(PL_lex_state);
2519 SAVESPTR(PL_lex_repl);
2520 SAVEVPTR(PL_lex_inpat);
2521 SAVEI16(PL_lex_inwhat);
2522 SAVECOPLINE(PL_curcop);
2523 SAVEPPTR(PL_bufptr);
2524 SAVEPPTR(PL_bufend);
2525 SAVEPPTR(PL_oldbufptr);
2526 SAVEPPTR(PL_oldoldbufptr);
2527 SAVEPPTR(PL_last_lop);
2528 SAVEPPTR(PL_last_uni);
2529 SAVEPPTR(PL_linestart);
2530 SAVESPTR(PL_linestr);
2531 SAVEGENERICPV(PL_lex_brackstack);
2532 SAVEGENERICPV(PL_lex_casestack);
2533 SAVEGENERICPV(PL_parser->lex_shared);
2534 SAVEBOOL(PL_parser->lex_re_reparsing);
2536 /* The here-doc parser needs to be able to peek into outer lexing
2537 scopes to find the body of the here-doc. So we put PL_linestr and
2538 PL_bufptr into lex_shared, to ‘share’ those values.
2540 PL_parser->lex_shared->ls_linestr = PL_linestr;
2541 PL_parser->lex_shared->ls_bufptr = PL_bufptr;
2543 PL_linestr = PL_lex_stuff;
2544 PL_lex_repl = PL_sublex_info.repl;
2545 PL_lex_stuff = NULL;
2546 PL_sublex_info.repl = NULL;
2548 PL_bufend = PL_bufptr = PL_oldbufptr = PL_oldoldbufptr = PL_linestart
2549 = SvPVX(PL_linestr);
2550 PL_bufend += SvCUR(PL_linestr);
2551 PL_last_lop = PL_last_uni = NULL;
2552 SAVEFREESV(PL_linestr);
2553 if (PL_lex_repl) SAVEFREESV(PL_lex_repl);
2555 PL_lex_dojoin = FALSE;
2556 PL_lex_brackets = PL_lex_formbrack = 0;
2557 PL_lex_allbrackets = 0;
2558 PL_lex_fakeeof = LEX_FAKEEOF_NEVER;
2559 Newx(PL_lex_brackstack, 120, char);
2560 Newx(PL_lex_casestack, 12, char);
2561 PL_lex_casemods = 0;
2562 *PL_lex_casestack = '\0';
2564 PL_lex_state = LEX_INTERPCONCAT;
2565 CopLINE_set(PL_curcop, (line_t)PL_multi_start);
2567 Newxz(shared, 1, LEXSHARED);
2568 shared->ls_prev = PL_parser->lex_shared;
2569 PL_parser->lex_shared = shared;
2571 PL_lex_inwhat = PL_sublex_info.sub_inwhat;
2572 if (PL_lex_inwhat == OP_TRANSR) PL_lex_inwhat = OP_TRANS;
2573 if (PL_lex_inwhat == OP_MATCH || PL_lex_inwhat == OP_QR || PL_lex_inwhat == OP_SUBST)
2574 PL_lex_inpat = PL_sublex_info.sub_op;
2576 PL_lex_inpat = NULL;
2578 PL_parser->lex_re_reparsing = cBOOL(PL_in_eval & EVAL_RE_REPARSING);
2579 PL_in_eval &= ~EVAL_RE_REPARSING;
2586 * Restores lexer state after a S_sublex_push.
2593 if (!PL_lex_starts++) {
2594 SV * const sv = newSVpvs("");
2595 if (SvUTF8(PL_linestr))
2597 PL_expect = XOPERATOR;
2598 pl_yylval.opval = (OP*)newSVOP(OP_CONST, 0, sv);
2602 if (PL_lex_casemods) { /* oops, we've got some unbalanced parens */
2603 PL_lex_state = LEX_INTERPCASEMOD;
2607 /* Is there a right-hand side to take care of? (s//RHS/ or tr//RHS/) */
2608 assert(PL_lex_inwhat != OP_TRANSR);
2609 if (PL_lex_repl && (PL_lex_inwhat == OP_SUBST || PL_lex_inwhat == OP_TRANS)) {
2610 PL_linestr = PL_lex_repl;
2612 PL_bufend = PL_bufptr = PL_oldbufptr = PL_oldoldbufptr = PL_linestart = SvPVX(PL_linestr);
2613 PL_bufend += SvCUR(PL_linestr);
2614 PL_last_lop = PL_last_uni = NULL;
2615 PL_lex_dojoin = FALSE;
2616 PL_lex_brackets = 0;
2617 PL_lex_allbrackets = 0;
2618 PL_lex_fakeeof = LEX_FAKEEOF_NEVER;
2619 PL_lex_casemods = 0;
2620 *PL_lex_casestack = '\0';
2622 if (SvEVALED(PL_lex_repl)) {
2623 PL_lex_state = LEX_INTERPNORMAL;
2625 /* we don't clear PL_lex_repl here, so that we can check later
2626 whether this is an evalled subst; that means we rely on the
2627 logic to ensure sublex_done() is called again only via the
2628 branch (in yylex()) that clears PL_lex_repl, else we'll loop */
2631 PL_lex_state = LEX_INTERPCONCAT;
2641 PL_endwhite = newSVpvs("");
2642 sv_catsv(PL_endwhite, PL_thiswhite);
2646 sv_setpvs(PL_thistoken,"");
2648 PL_realtokenstart = -1;
2652 PL_bufend = SvPVX(PL_linestr);
2653 PL_bufend += SvCUR(PL_linestr);
2654 PL_expect = XOPERATOR;
2655 PL_sublex_info.sub_inwhat = 0;
2660 PERL_STATIC_INLINE SV*
2661 S_get_and_check_backslash_N_name(pTHX_ const char* s, const char* const e)
2663 /* <s> points to first character of interior of \N{}, <e> to one beyond the
2664 * interior, hence to the "}". Finds what the name resolves to, returning
2665 * an SV* containing it; NULL if no valid one found */
2667 SV* res = newSVpvn_flags(s, e - s, UTF ? SVf_UTF8 : 0);
2674 const U8* first_bad_char_loc;
2675 const char* backslash_ptr = s - 3; /* Points to the <\> of \N{... */
2677 PERL_ARGS_ASSERT_GET_AND_CHECK_BACKSLASH_N_NAME;
2679 if (UTF && ! is_utf8_string_loc((U8 *) backslash_ptr,
2681 &first_bad_char_loc))
2683 /* If warnings are on, this will print a more detailed analysis of what
2684 * is wrong than the error message below */
2685 utf8n_to_uvuni(first_bad_char_loc,
2686 e - ((char *) first_bad_char_loc),
2689 /* We deliberately don't try to print the malformed character, which
2690 * might not print very well; it also may be just the first of many
2691 * malformations, so don't print what comes after it */
2692 yyerror(Perl_form(aTHX_
2693 "Malformed UTF-8 character immediately after '%.*s'",
2694 (int) (first_bad_char_loc - (U8 *) backslash_ptr), backslash_ptr));
2698 res = new_constant( NULL, 0, "charnames", res, NULL, backslash_ptr,
2699 /* include the <}> */
2700 e - backslash_ptr + 1);
2702 SvREFCNT_dec_NN(res);
2706 /* See if the charnames handler is the Perl core's, and if so, we can skip
2707 * the validation needed for a user-supplied one, as Perl's does its own
2709 table = GvHV(PL_hintgv); /* ^H */
2710 cvp = hv_fetchs(table, "charnames", FALSE);
2711 if (cvp && (cv = *cvp) && SvROK(cv) && ((rv = SvRV(cv)) != NULL)
2712 && SvTYPE(rv) == SVt_PVCV && ((stash = CvSTASH(rv)) != NULL))
2714 const char * const name = HvNAME(stash);
2715 if strEQ(name, "_charnames") {
2720 /* Here, it isn't Perl's charname handler. We can't rely on a
2721 * user-supplied handler to validate the input name. For non-ut8 input,
2722 * look to see that the first character is legal. Then loop through the
2723 * rest checking that each is a continuation */
2725 /* This code needs to be sync'ed with a regex in _charnames.pm which does
2729 if (! isALPHAU(*s)) {
2734 if (! isCHARNAME_CONT(*s)) {
2737 if (*s == ' ' && *(s-1) == ' ' && ckWARN_d(WARN_DEPRECATED)) {
2738 Perl_warner(aTHX_ packWARN(WARN_DEPRECATED),
2739 "A sequence of multiple spaces in a charnames "
2740 "alias definition is deprecated");
2744 if (*(s-1) == ' ' && ckWARN_d(WARN_DEPRECATED)) {
2745 Perl_warner(aTHX_ packWARN(WARN_DEPRECATED),
2746 "Trailing white-space in a charnames alias "
2747 "definition is deprecated");
2751 /* Similarly for utf8. For invariants can check directly; for other
2752 * Latin1, can calculate their code point and check; otherwise use a
2754 if (UTF8_IS_INVARIANT(*s)) {
2755 if (! isALPHAU(*s)) {
2759 } else if (UTF8_IS_DOWNGRADEABLE_START(*s)) {
2760 if (! isALPHAU(UNI_TO_NATIVE(TWO_BYTE_UTF8_TO_UNI(*s, *(s+1))))) {
2766 if (! PL_utf8_charname_begin) {
2767 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
2768 PL_utf8_charname_begin = _core_swash_init("utf8",
2769 "_Perl_Charname_Begin",
2771 1, 0, NULL, &flags);
2773 if (! swash_fetch(PL_utf8_charname_begin, (U8 *) s, TRUE)) {
2780 if (UTF8_IS_INVARIANT(*s)) {
2781 if (! isCHARNAME_CONT(*s)) {
2784 if (*s == ' ' && *(s-1) == ' '
2785 && ckWARN_d(WARN_DEPRECATED)) {
2786 Perl_warner(aTHX_ packWARN(WARN_DEPRECATED),
2787 "A sequence of multiple spaces in a charnam"
2788 "es alias definition is deprecated");
2792 else if (UTF8_IS_DOWNGRADEABLE_START(*s)) {
2793 if (! isCHARNAME_CONT(UNI_TO_NATIVE(TWO_BYTE_UTF8_TO_UNI(*s,
2801 if (! PL_utf8_charname_continue) {
2802 U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
2803 PL_utf8_charname_continue = _core_swash_init("utf8",
2804 "_Perl_Charname_Continue",
2806 1, 0, NULL, &flags);
2808 if (! swash_fetch(PL_utf8_charname_continue, (U8 *) s, TRUE)) {
2814 if (*(s-1) == ' ' && ckWARN_d(WARN_DEPRECATED)) {
2815 Perl_warner(aTHX_ packWARN(WARN_DEPRECATED),
2816 "Trailing white-space in a charnames alias "
2817 "definition is deprecated");
2821 if (SvUTF8(res)) { /* Don't accept malformed input */
2822 const U8* first_bad_char_loc;
2824 const char* const str = SvPV_const(res, len);
2825 if (! is_utf8_string_loc((U8 *) str, len, &first_bad_char_loc)) {
2826 /* If warnings are on, this will print a more detailed analysis of
2827 * what is wrong than the error message below */
2828 utf8n_to_uvuni(first_bad_char_loc,
2829 (char *) first_bad_char_loc - str,
2832 /* We deliberately don't try to print the malformed character,
2833 * which might not print very well; it also may be just the first
2834 * of many malformations, so don't print what comes after it */
2837 "Malformed UTF-8 returned by %.*s immediately after '%.*s'",
2838 (int) (e - backslash_ptr + 1), backslash_ptr,
2839 (int) ((char *) first_bad_char_loc - str), str
2849 int bad_char_size = ((UTF) ? UTF8SKIP(s) : 1);
2851 /* The final %.*s makes sure that should the trailing NUL be missing
2852 * that this print won't run off the end of the string */
2855 "Invalid character in \\N{...}; marked by <-- HERE in %.*s<-- HERE %.*s",
2856 (int)(s - backslash_ptr + bad_char_size), backslash_ptr,
2857 (int)(e - s + bad_char_size), s + bad_char_size
2859 UTF ? SVf_UTF8 : 0);
2867 Extracts the next constant part of a pattern, double-quoted string,
2868 or transliteration. This is terrifying code.
2870 For example, in parsing the double-quoted string "ab\x63$d", it would
2871 stop at the '$' and return an OP_CONST containing 'abc'.
2873 It looks at PL_lex_inwhat and PL_lex_inpat to find out whether it's
2874 processing a pattern (PL_lex_inpat is true), a transliteration
2875 (PL_lex_inwhat == OP_TRANS is true), or a double-quoted string.
2877 Returns a pointer to the character scanned up to. If this is
2878 advanced from the start pointer supplied (i.e. if anything was
2879 successfully parsed), will leave an OP_CONST for the substring scanned
2880 in pl_yylval. Caller must intuit reason for not parsing further
2881 by looking at the next characters herself.
2885 \N{FOO} => \N{U+hex_for_character_FOO}
2886 (if FOO expands to multiple characters, expands to \N{U+xx.XX.yy ...})
2889 all other \-char, including \N and \N{ apart from \N{ABC}
2892 @ and $ where it appears to be a var, but not for $ as tail anchor
2897 In transliterations:
2898 characters are VERY literal, except for - not at the start or end
2899 of the string, which indicates a range. If the range is in bytes,
2900 scan_const expands the range to the full set of intermediate
2901 characters. If the range is in utf8, the hyphen is replaced with
2902 a certain range mark which will be handled by pmtrans() in op.c.
2904 In double-quoted strings:
2906 double-quoted style: \r and \n
2907 constants: \x31, etc.
2908 deprecated backrefs: \1 (in substitution replacements)
2909 case and quoting: \U \Q \E
2912 scan_const does *not* construct ops to handle interpolated strings.
2913 It stops processing as soon as it finds an embedded $ or @ variable
2914 and leaves it to the caller to work out what's going on.
2916 embedded arrays (whether in pattern or not) could be:
2917 @foo, @::foo, @'foo, @{foo}, @$foo, @+, @-.
2919 $ in double-quoted strings must be the symbol of an embedded scalar.
2921 $ in pattern could be $foo or could be tail anchor. Assumption:
2922 it's a tail anchor if $ is the last thing in the string, or if it's
2923 followed by one of "()| \r\n\t"
2925 \1 (backreferences) are turned into $1 in substitutions
2927 The structure of the code is
2928 while (there's a character to process) {
2929 handle transliteration ranges
2930 skip regexp comments /(?#comment)/ and codes /(?{code})/
2931 skip #-initiated comments in //x patterns
2932 check for embedded arrays
2933 check for embedded scalars
2935 deprecate \1 in substitution replacements
2936 handle string-changing backslashes \l \U \Q \E, etc.
2937 switch (what was escaped) {
2938 handle \- in a transliteration (becomes a literal -)
2939 if a pattern and not \N{, go treat as regular character
2940 handle \132 (octal characters)
2941 handle \x15 and \x{1234} (hex characters)
2942 handle \N{name} (named characters, also \N{3,5} in a pattern)
2943 handle \cV (control characters)
2944 handle printf-style backslashes (\f, \r, \n, etc)
2947 } (end if backslash)
2948 handle regular character
2949 } (end while character to read)
2954 S_scan_const(pTHX_ char *start)
2957 char *send = PL_bufend; /* end of the constant */
2958 SV *sv = newSV(send - start); /* sv for the constant. See
2959 note below on sizing. */
2960 char *s = start; /* start of the constant */
2961 char *d = SvPVX(sv); /* destination for copies */
2962 bool dorange = FALSE; /* are we in a translit range? */
2963 bool didrange = FALSE; /* did we just finish a range? */
2964 bool in_charclass = FALSE; /* within /[...]/ */
2965 bool has_utf8 = FALSE; /* Output constant is UTF8 */
2966 bool this_utf8 = cBOOL(UTF); /* Is the source string assumed
2967 to be UTF8? But, this can
2968 show as true when the source
2969 isn't utf8, as for example
2970 when it is entirely composed
2972 SV *res; /* result from charnames */
2974 /* Note on sizing: The scanned constant is placed into sv, which is
2975 * initialized by newSV() assuming one byte of output for every byte of
2976 * input. This routine expects newSV() to allocate an extra byte for a
2977 * trailing NUL, which this routine will append if it gets to the end of
2978 * the input. There may be more bytes of input than output (eg., \N{LATIN
2979 * CAPITAL LETTER A}), or more output than input if the constant ends up
2980 * recoded to utf8, but each time a construct is found that might increase
2981 * the needed size, SvGROW() is called. Its size parameter each time is
2982 * based on the best guess estimate at the time, namely the length used so
2983 * far, plus the length the current construct will occupy, plus room for
2984 * the trailing NUL, plus one byte for every input byte still unscanned */
2986 UV uv = UV_MAX; /* Initialize to weird value to try to catch any uses
2989 UV literal_endpoint = 0;
2990 bool native_range = TRUE; /* turned to FALSE if the first endpoint is Unicode. */
2993 PERL_ARGS_ASSERT_SCAN_CONST;
2995 assert(PL_lex_inwhat != OP_TRANSR);
2996 if (PL_lex_inwhat == OP_TRANS && PL_sublex_info.sub_op) {
2997 /* If we are doing a trans and we know we want UTF8 set expectation */
2998 has_utf8 = PL_sublex_info.sub_op->op_private & (OPpTRANS_FROM_UTF|OPpTRANS_TO_UTF);
2999 this_utf8 = PL_sublex_info.sub_op->op_private & (PL_lex_repl ? OPpTRANS_FROM_UTF : OPpTRANS_TO_UTF);
3002 /* Protect sv from errors and fatal warnings. */
3003 ENTER_with_name("scan_const");
3006 while (s < send || dorange) {
3008 /* get transliterations out of the way (they're most literal) */
3009 if (PL_lex_inwhat == OP_TRANS) {
3010 /* expand a range A-Z to the full set of characters. AIE! */
3012 I32 i; /* current expanded character */
3013 I32 min; /* first character in range */
3014 I32 max; /* last character in range */
3025 char * const c = (char*)utf8_hop((U8*)d, -1);
3029 *c = (char)UTF_TO_NATIVE(0xff);
3030 /* mark the range as done, and continue */
3036 i = d - SvPVX_const(sv); /* remember current offset */
3039 SvLEN(sv) + (has_utf8 ?
3040 (512 - UTF_CONTINUATION_MARK +
3043 /* How many two-byte within 0..255: 128 in UTF-8,
3044 * 96 in UTF-8-mod. */
3046 SvGROW(sv, SvLEN(sv) + 256); /* never more than 256 chars in a range */
3048 d = SvPVX(sv) + i; /* refresh d after realloc */
3052 for (j = 0; j <= 1; j++) {
3053 char * const c = (char*)utf8_hop((U8*)d, -1);
3054 const UV uv = utf8n_to_uvchr((U8*)c, d - c, NULL, 0);
3060 max = (U8)0xff; /* only to \xff */
3061 uvmax = uv; /* \x{100} to uvmax */
3063 d = c; /* eat endpoint chars */
3068 d -= 2; /* eat the first char and the - */
3069 min = (U8)*d; /* first char in range */
3070 max = (U8)d[1]; /* last char in range */
3077 "Invalid range \"%c-%c\" in transliteration operator",
3078 (char)min, (char)max);
3082 if (literal_endpoint == 2 &&
3083 ((isLOWER(min) && isLOWER(max)) ||
3084 (isUPPER(min) && isUPPER(max)))) {
3086 for (i = min; i <= max; i++)
3088 *d++ = NATIVE_TO_NEED(has_utf8,i);
3090 for (i = min; i <= max; i++)
3092 *d++ = NATIVE_TO_NEED(has_utf8,i);
3097 for (i = min; i <= max; i++)
3100 const U8 ch = (U8)NATIVE_TO_UTF(i);
3101 if (UNI_IS_INVARIANT(ch))
3104 *d++ = (U8)UTF8_EIGHT_BIT_HI(ch);
3105 *d++ = (U8)UTF8_EIGHT_BIT_LO(ch);
3114 d = (char*)uvchr_to_utf8((U8*)d, 0x100);
3116 *d++ = (char)UTF_TO_NATIVE(0xff);
3118 d = (char*)uvchr_to_utf8((U8*)d, uvmax);
3122 /* mark the range as done, and continue */
3126 literal_endpoint = 0;
3131 /* range begins (ignore - as first or last char) */
3132 else if (*s == '-' && s+1 < send && s != start) {
3134 Perl_croak(aTHX_ "Ambiguous range in transliteration operator");
3141 *d++ = (char)UTF_TO_NATIVE(0xff); /* use illegal utf8 byte--see pmtrans */
3151 literal_endpoint = 0;
3152 native_range = TRUE;
3157 /* if we get here, we're not doing a transliteration */
3159 else if (*s == '[' && PL_lex_inpat && !in_charclass) {
3162 while (s1 >= start && *s1-- == '\\')
3165 in_charclass = TRUE;
3168 else if (*s == ']' && PL_lex_inpat && in_charclass) {
3171 while (s1 >= start && *s1-- == '\\')
3174 in_charclass = FALSE;
3177 /* skip for regexp comments /(?#comment)/, except for the last
3178 * char, which will be done separately.
3179 * Stop on (?{..}) and friends */
3181 else if (*s == '(' && PL_lex_inpat && s[1] == '?') {
3183 while (s+1 < send && *s != ')')
3184 *d++ = NATIVE_TO_NEED(has_utf8,*s++);
3186 else if (!PL_lex_casemods && !in_charclass &&
3187 ( s[2] == '{' /* This should match regcomp.c */
3188 || (s[2] == '?' && s[3] == '{')))
3194 /* likewise skip #-initiated comments in //x patterns */
3195 else if (*s == '#' && PL_lex_inpat &&
3196 ((PMOP*)PL_lex_inpat)->op_pmflags & RXf_PMf_EXTENDED) {
3197 while (s+1 < send && *s != '\n')
3198 *d++ = NATIVE_TO_NEED(has_utf8,*s++);
3201 /* no further processing of single-quoted regex */
3202 else if (PL_lex_inpat && SvIVX(PL_linestr) == '\'')
3203 goto default_action;
3205 /* check for embedded arrays
3206 (@foo, @::foo, @'foo, @{foo}, @$foo, @+, @-)
3208 else if (*s == '@' && s[1]) {
3209 if (isWORDCHAR_lazy_if(s+1,UTF))
3211 if (strchr(":'{$", s[1]))
3213 if (!PL_lex_inpat && (s[1] == '+' || s[1] == '-'))
3214 break; /* in regexp, neither @+ nor @- are interpolated */
3217 /* check for embedded scalars. only stop if we're sure it's a
3220 else if (*s == '$') {
3221 if (!PL_lex_inpat) /* not a regexp, so $ must be var */
3223 if (s + 1 < send && !strchr("()| \r\n\t", s[1])) {
3225 Perl_ck_warner(aTHX_ packWARN(WARN_AMBIGUOUS),
3226 "Possible unintended interpolation of $\\ in regex");
3228 break; /* in regexp, $ might be tail anchor */
3232 /* End of else if chain - OP_TRANS rejoin rest */
3235 if (*s == '\\' && s+1 < send) {
3236 char* e; /* Can be used for ending '}', etc. */
3240 /* warn on \1 - \9 in substitution replacements, but note that \11
3241 * is an octal; and \19 is \1 followed by '9' */
3242 if (PL_lex_inwhat == OP_SUBST && !PL_lex_inpat &&
3243 isDIGIT(*s) && *s != '0' && !isDIGIT(s[1]))
3245 Perl_ck_warner(aTHX_ packWARN(WARN_SYNTAX), "\\%c better written as $%c", *s, *s);
3250 /* string-change backslash escapes */
3251 if (PL_lex_inwhat != OP_TRANS && *s && strchr("lLuUEQF", *s)) {
3255 /* In a pattern, process \N, but skip any other backslash escapes.
3256 * This is because we don't want to translate an escape sequence
3257 * into a meta symbol and have the regex compiler use the meta
3258 * symbol meaning, e.g. \x{2E} would be confused with a dot. But
3259 * in spite of this, we do have to process \N here while the proper
3260 * charnames handler is in scope. See bugs #56444 and #62056.
3261 * There is a complication because \N in a pattern may also stand
3262 * for 'match a non-nl', and not mean a charname, in which case its
3263 * processing should be deferred to the regex compiler. To be a
3264 * charname it must be followed immediately by a '{', and not look
3265 * like \N followed by a curly quantifier, i.e., not something like
3266 * \N{3,}. regcurly returns a boolean indicating if it is a legal
3268 else if (PL_lex_inpat
3271 || regcurly(s + 1, FALSE)))
3273 *d++ = NATIVE_TO_NEED(has_utf8,'\\');
3274 goto default_action;
3279 /* quoted - in transliterations */
3281 if (PL_lex_inwhat == OP_TRANS) {
3288 if ((isALPHANUMERIC(*s)))
3289 Perl_ck_warner(aTHX_ packWARN(WARN_MISC),
3290 "Unrecognized escape \\%c passed through",
3292 /* default action is to copy the quoted character */
3293 goto default_action;
3296 /* eg. \132 indicates the octal constant 0132 */
3297 case '0': case '1': case '2': case '3':
3298 case '4': case '5': case '6': case '7':
3300 I32 flags = PERL_SCAN_SILENT_ILLDIGIT;
3302 uv = NATIVE_TO_UNI(grok_oct(s, &len, &flags, NULL));
3304 if (len < 3 && s < send && isDIGIT(*s)
3305 && ckWARN(WARN_MISC))
3307 Perl_warner(aTHX_ packWARN(WARN_MISC),
3308 "%s", form_short_octal_warning(s, len));
3311 goto NUM_ESCAPE_INSERT;
3313 /* eg. \o{24} indicates the octal constant \024 */
3318 bool valid = grok_bslash_o(&s, &uv, &error,
3319 TRUE, /* Output warning */
3320 FALSE, /* Not strict */
3321 TRUE, /* Output warnings for
3328 goto NUM_ESCAPE_INSERT;
3331 /* eg. \x24 indicates the hex constant 0x24 */
3336 bool valid = grok_bslash_x(&s, &uv, &error,
3337 TRUE, /* Output warning */
3338 FALSE, /* Not strict */
3339 TRUE, /* Output warnings for
3349 /* Insert oct or hex escaped character. There will always be
3350 * enough room in sv since such escapes will be longer than any
3351 * UTF-8 sequence they can end up as, except if they force us
3352 * to recode the rest of the string into utf8 */
3354 /* Here uv is the ordinal of the next character being added in
3355 * unicode (converted from native). */
3356 if (!UNI_IS_INVARIANT(uv)) {
3357 if (!has_utf8 && uv > 255) {
3358 /* Might need to recode whatever we have accumulated so
3359 * far if it contains any chars variant in utf8 or
3362 SvCUR_set(sv, d - SvPVX_const(sv));
3365 /* See Note on sizing above. */
3366 sv_utf8_upgrade_flags_grow(sv,
3367 SV_GMAGIC|SV_FORCE_UTF8_UPGRADE,
3368 UNISKIP(uv) + (STRLEN)(send - s) + 1);
3369 d = SvPVX(sv) + SvCUR(sv);
3374 d = (char*)uvuni_to_utf8((U8*)d, uv);
3375 if (PL_lex_inwhat == OP_TRANS &&
3376 PL_sublex_info.sub_op) {
3377 PL_sublex_info.sub_op->op_private |=
3378 (PL_lex_repl ? OPpTRANS_FROM_UTF
3382 if (uv > 255 && !dorange)
3383 native_range = FALSE;
3396 /* In a non-pattern \N must be a named character, like \N{LATIN
3397 * SMALL LETTER A} or \N{U+0041}. For patterns, it also can
3398 * mean to match a non-newline. For non-patterns, named
3399 * characters are converted to their string equivalents. In
3400 * patterns, named characters are not converted to their
3401 * ultimate forms for the same reasons that other escapes
3402 * aren't. Instead, they are converted to the \N{U+...} form
3403 * to get the value from the charnames that is in effect right
3404 * now, while preserving the fact that it was a named character
3405 * so that the regex compiler knows this */
3407 /* This section of code doesn't generally use the
3408 * NATIVE_TO_NEED() macro to transform the input. I (khw) did
3409 * a close examination of this macro and determined it is a
3410 * no-op except on utfebcdic variant characters. Every
3411 * character generated by this that would normally need to be
3412 * enclosed by this macro is invariant, so the macro is not
3413 * needed, and would complicate use of copy(). XXX There are
3414 * other parts of this file where the macro is used
3415 * inconsistently, but are saved by it being a no-op */
3417 /* The structure of this section of code (besides checking for
3418 * errors and upgrading to utf8) is:
3419 * Further disambiguate between the two meanings of \N, and if
3420 * not a charname, go process it elsewhere
3421 * If of form \N{U+...}, pass it through if a pattern;
3422 * otherwise convert to utf8
3423 * Otherwise must be \N{NAME}: convert to \N{U+c1.c2...} if a
3424 * pattern; otherwise convert to utf8 */
3426 /* Here, s points to the 'N'; the test below is guaranteed to
3427 * succeed if we are being called on a pattern as we already
3428 * know from a test above that the next character is a '{'.
3429 * On a non-pattern \N must mean 'named sequence, which
3430 * requires braces */
3433 yyerror("Missing braces on \\N{}");
3438 /* If there is no matching '}', it is an error. */
3439 if (! (e = strchr(s, '}'))) {
3440 if (! PL_lex_inpat) {
3441 yyerror("Missing right brace on \\N{}");
3443 yyerror("Missing right brace on \\N{} or unescaped left brace after \\N.");
3448 /* Here it looks like a named character */
3450 if (*s == 'U' && s[1] == '+') { /* \N{U+...} */
3451 I32 flags = PERL_SCAN_ALLOW_UNDERSCORES
3452 | PERL_SCAN_DISALLOW_PREFIX;
3455 /* For \N{U+...}, the '...' is a unicode value even on
3456 * EBCDIC machines */
3457 s += 2; /* Skip to next char after the 'U+' */
3459 uv = grok_hex(s, &len, &flags, NULL);
3460 if (len == 0 || len != (STRLEN)(e - s)) {
3461 yyerror("Invalid hexadecimal number in \\N{U+...}");
3468 /* On non-EBCDIC platforms, pass through to the regex
3469 * compiler unchanged. The reason we evaluated the
3470 * number above is to make sure there wasn't a syntax
3471 * error. But on EBCDIC we convert to native so
3472 * downstream code can continue to assume it's native
3474 s -= 5; /* Include the '\N{U+' */
3476 d += my_snprintf(d, e - s + 1 + 1, /* includes the }
3479 (unsigned int) UNI_TO_NATIVE(uv));
3481 Copy(s, d, e - s + 1, char); /* 1 = include the } */
3485 else { /* Not a pattern: convert the hex to string */
3487 /* If destination is not in utf8, unconditionally
3488 * recode it to be so. This is because \N{} implies
3489 * Unicode semantics, and scalars have to be in utf8
3490 * to guarantee those semantics */
3492 SvCUR_set(sv, d - SvPVX_const(sv));
3495 /* See Note on sizing above. */
3496 sv_utf8_upgrade_flags_grow(
3498 SV_GMAGIC|SV_FORCE_UTF8_UPGRADE,
3499 UNISKIP(uv) + (STRLEN)(send - e) + 1);
3500 d = SvPVX(sv) + SvCUR(sv);
3504 /* Add the string to the output */
3505 if (UNI_IS_INVARIANT(uv)) {
3508 else d = (char*)uvuni_to_utf8((U8*)d, uv);
3511 else /* Here is \N{NAME} but not \N{U+...}. */
3512 if ((res = get_and_check_backslash_N_name(s, e)))
3515 const char *str = SvPV_const(res, len);
3518 if (! len) { /* The name resolved to an empty string */
3519 Copy("\\N{}", d, 4, char);
3523 /* In order to not lose information for the regex
3524 * compiler, pass the result in the specially made
3525 * syntax: \N{U+c1.c2.c3...}, where c1 etc. are
3526 * the code points in hex of each character
3527 * returned by charnames */
3529 const char *str_end = str + len;
3530 const STRLEN off = d - SvPVX_const(sv);
3532 if (! SvUTF8(res)) {
3533 /* For the non-UTF-8 case, we can determine the
3534 * exact length needed without having to parse
3535 * through the string. Each character takes up
3536 * 2 hex digits plus either a trailing dot or
3538 d = off + SvGROW(sv, off
3540 + 6 /* For the "\N{U+", and
3542 + (STRLEN)(send - e));
3543 Copy("\\N{U+", d, 5, char);
3545 while (str < str_end) {
3547 my_snprintf(hex_string, sizeof(hex_string),
3548 "%02X.", (U8) *str);
3549 Copy(hex_string, d, 3, char);
3553 d--; /* We will overwrite below the final
3554 dot with a right brace */
3557 STRLEN char_length; /* cur char's byte length */
3559 /* and the number of bytes after this is
3560 * translated into hex digits */
3561 STRLEN output_length;
3563 /* 2 hex per byte; 2 chars for '\N'; 2 chars
3564 * for max('U+', '.'); and 1 for NUL */
3565 char hex_string[2 * UTF8_MAXBYTES + 5];
3567 /* Get the first character of the result. */
3568 U32 uv = utf8n_to_uvuni((U8 *) str,
3572 /* Convert first code point to hex, including
3573 * the boiler plate before it. For all these,
3574 * we convert to native format so that
3575 * downstream code can continue to assume the
3576 * input is native */
3578 my_snprintf(hex_string, sizeof(hex_string),
3580 (unsigned int) UNI_TO_NATIVE(uv));
3582 /* Make sure there is enough space to hold it */
3583 d = off + SvGROW(sv, off
3585 + (STRLEN)(send - e)
3586 + 2); /* '}' + NUL */
3588 Copy(hex_string, d, output_length, char);
3591 /* For each subsequent character, append dot and
3592 * its ordinal in hex */
3593 while ((str += char_length) < str_end) {
3594 const STRLEN off = d - SvPVX_const(sv);
3595 U32 uv = utf8n_to_uvuni((U8 *) str,
3600 my_snprintf(hex_string,
3603 (unsigned int) UNI_TO_NATIVE(uv));
3605 d = off + SvGROW(sv, off
3607 + (STRLEN)(send - e)
3608 + 2); /* '}' + NUL */
3609 Copy(hex_string, d, output_length, char);
3614 *d++ = '}'; /* Done. Add the trailing brace */
3617 else { /* Here, not in a pattern. Convert the name to a
3620 /* If destination is not in utf8, unconditionally
3621 * recode it to be so. This is because \N{} implies
3622 * Unicode semantics, and scalars have to be in utf8
3623 * to guarantee those semantics */
3625 SvCUR_set(sv, d - SvPVX_const(sv));
3628 /* See Note on sizing above. */
3629 sv_utf8_upgrade_flags_grow(sv,
3630 SV_GMAGIC|SV_FORCE_UTF8_UPGRADE,
3631 len + (STRLEN)(send - s) + 1);
3632 d = SvPVX(sv) + SvCUR(sv);
3634 } else if (len > (STRLEN)(e - s + 4)) { /* I _guess_ 4 is \N{} --jhi */
3636 /* See Note on sizing above. (NOTE: SvCUR() is not
3637 * set correctly here). */
3638 const STRLEN off = d - SvPVX_const(sv);
3639 d = off + SvGROW(sv, off + len + (STRLEN)(send - s) + 1);
3641 Copy(str, d, len, char);
3647 } /* End \N{NAME} */
3650 native_range = FALSE; /* \N{} is defined to be Unicode */
3652 s = e + 1; /* Point to just after the '}' */
3655 /* \c is a control character */
3659 *d++ = grok_bslash_c(*s++, has_utf8, 1);
3662 yyerror("Missing control char name in \\c");
3666 /* printf-style backslashes, formfeeds, newlines, etc */
3668 *d++ = NATIVE_TO_NEED(has_utf8,'\b');
3671 *d++ = NATIVE_TO_NEED(has_utf8,'\n');
3674 *d++ = NATIVE_TO_NEED(has_utf8,'\r');
3677 *d++ = NATIVE_TO_NEED(has_utf8,'\f');
3680 *d++ = NATIVE_TO_NEED(has_utf8,'\t');
3683 *d++ = ASCII_TO_NEED(has_utf8,'\033');
3686 *d++ = ASCII_TO_NEED(has_utf8,'\007');
3692 } /* end if (backslash) */
3699 /* If we started with encoded form, or already know we want it,
3700 then encode the next character */
3701 if (! NATIVE_IS_INVARIANT((U8)(*s)) && (this_utf8 || has_utf8)) {
3705 /* One might think that it is wasted effort in the case of the
3706 * source being utf8 (this_utf8 == TRUE) to take the next character
3707 * in the source, convert it to an unsigned value, and then convert
3708 * it back again. But the source has not been validated here. The
3709 * routine that does the conversion checks for errors like
3712 const UV nextuv = (this_utf8) ? utf8n_to_uvchr((U8*)s, send - s, &len, 0) : (UV) ((U8) *s);
3713 const STRLEN need = UNISKIP(NATIVE_TO_UNI(nextuv));
3715 SvCUR_set(sv, d - SvPVX_const(sv));
3718 /* See Note on sizing above. */
3719 sv_utf8_upgrade_flags_grow(sv,
3720 SV_GMAGIC|SV_FORCE_UTF8_UPGRADE,
3721 need + (STRLEN)(send - s) + 1);
3722 d = SvPVX(sv) + SvCUR(sv);
3724 } else if (need > len) {
3725 /* encoded value larger than old, may need extra space (NOTE:
3726 * SvCUR() is not set correctly here). See Note on sizing
3728 const STRLEN off = d - SvPVX_const(sv);
3729 d = SvGROW(sv, off + need + (STRLEN)(send - s) + 1) + off;
3733 d = (char*)uvchr_to_utf8((U8*)d, nextuv);
3735 if (uv > 255 && !dorange)
3736 native_range = FALSE;
3740 *d++ = NATIVE_TO_NEED(has_utf8,*s++);
3742 } /* while loop to process each character */
3744 /* terminate the string and set up the sv */
3746 SvCUR_set(sv, d - SvPVX_const(sv));
3747 if (SvCUR(sv) >= SvLEN(sv))
3748 Perl_croak(aTHX_ "panic: constant overflowed allocated space, %"UVuf
3749 " >= %"UVuf, (UV)SvCUR(sv), (UV)SvLEN(sv));
3752 if (PL_encoding && !has_utf8) {
3753 sv_recode_to_utf8(sv, PL_encoding);
3759 if (PL_lex_inwhat == OP_TRANS && PL_sublex_info.sub_op) {
3760 PL_sublex_info.sub_op->op_private |=
3761 (PL_lex_repl ? OPpTRANS_FROM_UTF : OPpTRANS_TO_UTF);
3765 /* shrink the sv if we allocated more than we used */
3766 if (SvCUR(sv) + 5 < SvLEN(sv)) {
3767 SvPV_shrink_to_cur(sv);
3770 /* return the substring (via pl_yylval) only if we parsed anything */
3771 if (s > PL_bufptr) {
3772 SvREFCNT_inc_simple_void_NN(sv);
3773 if ( (PL_hints & ( PL_lex_inpat ? HINT_NEW_RE : HINT_NEW_STRING ))
3774 && ! PL_parser->lex_re_reparsing)
3776 const char *const key = PL_lex_inpat ? "qr" : "q";
3777 const STRLEN keylen = PL_lex_inpat ? 2 : 1;
3781 if (PL_lex_inwhat == OP_TRANS) {
3784 } else if (PL_lex_inwhat == OP_SUBST && !PL_lex_inpat) {
3787 } else if (PL_lex_inpat && SvIVX(PL_linestr) == '\'') {
3795 sv = S_new_constant(aTHX_ start, s - start, key, keylen, sv, NULL,
3798 pl_yylval.opval = (OP*)newSVOP(OP_CONST, 0, sv);
3800 LEAVE_with_name("scan_const");
3805 * Returns TRUE if there's more to the expression (e.g., a subscript),
3808 * It deals with "$foo[3]" and /$foo[3]/ and /$foo[0123456789$]+/
3810 * ->[ and ->{ return TRUE
3811 * { and [ outside a pattern are always subscripts, so return TRUE
3812 * if we're outside a pattern and it's not { or [, then return FALSE
3813 * if we're in a pattern and the first char is a {
3814 * {4,5} (any digits around the comma) returns FALSE
3815 * if we're in a pattern and the first char is a [
3817 * [SOMETHING] has a funky algorithm to decide whether it's a
3818 * character class or not. It has to deal with things like
3819 * /$foo[-3]/ and /$foo[$bar]/ as well as /$foo[$\d]+/
3820 * anything else returns TRUE
3823 /* This is the one truly awful dwimmer necessary to conflate C and sed. */
3826 S_intuit_more(pTHX_ char *s)
3830 PERL_ARGS_ASSERT_INTUIT_MORE;
3832 if (PL_lex_brackets)
3834 if (*s == '-' && s[1] == '>' && (s[2] == '[' || s[2] == '{'))
3836 if (*s != '{' && *s != '[')
3841 /* In a pattern, so maybe we have {n,m}. */
3843 if (regcurly(s, FALSE)) {
3849 /* On the other hand, maybe we have a character class */
3852 if (*s == ']' || *s == '^')
3855 /* this is terrifying, and it works */
3858 const char * const send = strchr(s,']');
3859 unsigned char un_char, last_un_char;
3860 char tmpbuf[sizeof PL_tokenbuf * 4];
3862 if (!send) /* has to be an expression */
3864 weight = 2; /* let's weigh the evidence */
3868 else if (isDIGIT(*s)) {
3870 if (isDIGIT(s[1]) && s[2] == ']')
3876 Zero(seen,256,char);
3878 for (; s < send; s++) {
3879 last_un_char = un_char;
3880 un_char = (unsigned char)*s;
3885 weight -= seen[un_char] * 10;
3886 if (isWORDCHAR_lazy_if(s+1,UTF)) {
3888 scan_ident(s, send, tmpbuf, sizeof tmpbuf, FALSE);
3889 len = (int)strlen(tmpbuf);
3890 if (len > 1 && gv_fetchpvn_flags(tmpbuf, len,
3891 UTF ? SVf_UTF8 : 0, SVt_PV))
3896 else if (*s == '$' && s[1] &&
3897 strchr("[#!%*<>()-=",s[1])) {
3898 if (/*{*/ strchr("])} =",s[2]))
3907 if (strchr("wds]",s[1]))
3909 else if (seen[(U8)'\''] || seen[(U8)'"'])
3911 else if (strchr("rnftbxcav",s[1]))
3913 else if (isDIGIT(s[1])) {
3915 while (s[1] && isDIGIT(s[1]))
3925 if (strchr("aA01! ",last_un_char))
3927 if (strchr("zZ79~",s[1]))
3929 if (last_un_char == 255 && (isDIGIT(s[1]) || s[1] == '$'))
3930 weight -= 5; /* cope with negative subscript */
3933 if (!isWORDCHAR(last_un_char)
3934 && !(last_un_char == '$' || last_un_char == '@'
3935 || last_un_char == '&')
3936 && isALPHA(*s) && s[1] && isALPHA(s[1])) {
3941 if (keyword(tmpbuf, d - tmpbuf, 0))
3944 if (un_char == last_un_char + 1)
3946 weight -= seen[un_char];
3951 if (weight >= 0) /* probably a character class */
3961 * Does all the checking to disambiguate
3963 * between foo(bar) and bar->foo. Returns 0 if not a method, otherwise
3964 * FUNCMETH (bar->foo(args)) or METHOD (bar->foo args).
3966 * First argument is the stuff after the first token, e.g. "bar".
3968 * Not a method if foo is a filehandle.
3969 * Not a method if foo is a subroutine prototyped to take a filehandle.
3970 * Not a method if it's really "Foo $bar"
3971 * Method if it's "foo $bar"
3972 * Not a method if it's really "print foo $bar"
3973 * Method if it's really "foo package::" (interpreted as package->foo)
3974 * Not a method if bar is known to be a subroutine ("sub bar; foo bar")
3975 * Not a method if bar is a filehandle or package, but is quoted with
3980 S_intuit_method(pTHX_ char *start, GV *gv, CV *cv)
3983 char *s = start + (*start == '$');
3984 char tmpbuf[sizeof PL_tokenbuf];
3991 PERL_ARGS_ASSERT_INTUIT_METHOD;
3993 if (gv && SvTYPE(gv) == SVt_PVGV && GvIO(gv))
3995 if (cv && SvPOK(cv)) {
3996 const char *proto = CvPROTO(cv);
3998 while (*proto && (isSPACE(*proto) || *proto == ';'))
4005 if (*start == '$') {
4006 if (cv || PL_last_lop_op == OP_PRINT || PL_last_lop_op == OP_SAY ||
4007 isUPPER(*PL_tokenbuf))
4010 len = start - SvPVX(PL_linestr);
4014 start = SvPVX(PL_linestr) + len;
4018 return *s == '(' ? FUNCMETH : METHOD;
4021 s = scan_word(s, tmpbuf, sizeof tmpbuf, TRUE, &len);
4022 /* start is the beginning of the possible filehandle/object,
4023 * and s is the end of it
4024 * tmpbuf is a copy of it (but with single quotes as double colons)
4027 if (!keyword(tmpbuf, len, 0)) {
4028 if (len > 2 && tmpbuf[len - 2] == ':' && tmpbuf[len - 1] == ':') {
4032 soff = s - SvPVX(PL_linestr);
4036 indirgv = gv_fetchpvn_flags(tmpbuf, len, ( UTF ? SVf_UTF8 : 0 ), SVt_PVCV);
4037 if (indirgv && GvCVu(indirgv))
4039 /* filehandle or package name makes it a method */
4040 if (!cv || GvIO(indirgv) || gv_stashpvn(tmpbuf, len, UTF ? SVf_UTF8 : 0)) {
4042 soff = s - SvPVX(PL_linestr);
4045 if ((PL_bufend - s) >= 2 && *s == '=' && *(s+1) == '>')
4046 return 0; /* no assumptions -- "=>" quotes bareword */
4048 start_force(PL_curforce);
4049 NEXTVAL_NEXTTOKE.opval = (OP*)newSVOP(OP_CONST, 0,
4050 S_newSV_maybe_utf8(aTHX_ tmpbuf, len));
4051 NEXTVAL_NEXTTOKE.opval->op_private = OPpCONST_BARE;
4053 curmad('X', newSVpvn_flags(start,SvPVX(PL_linestr) + soff - start,
4054 ( UTF ? SVf_UTF8 : 0 )));
4059 PL_bufptr = SvPVX(PL_linestr) + soff; /* restart before space */
4061 return *s == '(' ? FUNCMETH : METHOD;
4067 /* Encoded script support. filter_add() effectively inserts a
4068 * 'pre-processing' function into the current source input stream.
4069 * Note that the filter function only applies to the current source file
4070 * (e.g., it will not affect files 'require'd or 'use'd by this one).
4072 * The datasv parameter (which may be NULL) can be used to pass
4073 * private data to this instance of the filter. The filter function
4074 * can recover the SV using the FILTER_DATA macro and use it to
4075 * store private buffers and state information.
4077 * The supplied datasv parameter is upgraded to a PVIO type
4078 * and the IoDIRP/IoANY field is used to store the function pointer,
4079 * and IOf_FAKE_DIRP is enabled on datasv to mark this as such.
4080 * Note that IoTOP_NAME, IoFMT_NAME, IoBOTTOM_NAME, if set for
4081 * private use must be set using malloc'd pointers.
4085 Perl_filter_add(pTHX_ filter_t funcp, SV *datasv)
4094 if (PL_parser->lex_flags & LEX_IGNORE_UTF8_HINTS)
4095 Perl_croak(aTHX_ "Source filters apply only to byte streams");
4097 if (!PL_rsfp_filters)
4098 PL_rsfp_filters = newAV();
4101 SvUPGRADE(datasv, SVt_PVIO);
4102 IoANY(datasv) = FPTR2DPTR(void *, funcp); /* stash funcp into spare field */
4103 IoFLAGS(datasv) |= IOf_FAKE_DIRP;
4104 DEBUG_P(PerlIO_printf(Perl_debug_log, "filter_add func %p (%s)\n",
4105 FPTR2DPTR(void *, IoANY(datasv)),
4106 SvPV_nolen(datasv)));
4107 av_unshift(PL_rsfp_filters, 1);
4108 av_store(PL_rsfp_filters, 0, datasv) ;
4110 !PL_parser->filtered
4111 && PL_parser->lex_flags & LEX_EVALBYTES
4112 && PL_bufptr < PL_bufend
4114 const char *s = PL_bufptr;
4115 while (s < PL_bufend) {
4117 SV *linestr = PL_parser->linestr;
4118 char *buf = SvPVX(linestr);
4119 STRLEN const bufptr_pos = PL_parser->bufptr - buf;
4120 STRLEN const oldbufptr_pos = PL_parser->oldbufptr - buf;
4121 STRLEN const oldoldbufptr_pos=PL_parser->oldoldbufptr-buf;
4122 STRLEN const linestart_pos = PL_parser->linestart - buf;
4123 STRLEN const last_uni_pos =
4124 PL_parser->last_uni ? PL_parser->last_uni - buf : 0;
4125 STRLEN const last_lop_pos =
4126 PL_parser->last_lop ? PL_parser->last_lop - buf : 0;
4127 av_push(PL_rsfp_filters, linestr);
4128 PL_parser->linestr =
4129 newSVpvn(SvPVX(linestr), ++s-SvPVX(linestr));
4130 buf = SvPVX(PL_parser->linestr);
4131 PL_parser->bufend = buf + SvCUR(PL_parser->linestr);
4132 PL_parser->bufptr = buf + bufptr_pos;
4133 PL_parser->oldbufptr = buf + oldbufptr_pos;
4134 PL_parser->oldoldbufptr = buf + oldoldbufptr_pos;
4135 PL_parser->linestart = buf + linestart_pos;
4136 if (PL_parser->last_uni)
4137 PL_parser->last_uni = buf + last_uni_pos;
4138 if (PL_parser->last_lop)
4139 PL_parser->last_lop = buf + last_lop_pos;
4140 SvLEN(linestr) = SvCUR(linestr);
4141 SvCUR(linestr) = s-SvPVX(linestr);
4142 PL_parser->filtered = 1;
4152 /* Delete most recently added instance of this filter function. */
4154 Perl_filter_del(pTHX_ filter_t funcp)
4159 PERL_ARGS_ASSERT_FILTER_DEL;
4162 DEBUG_P(PerlIO_printf(Perl_debug_log, "filter_del func %p",
4163 FPTR2DPTR(void*, funcp)));
4165 if (!PL_parser || !PL_rsfp_filters || AvFILLp(PL_rsfp_filters)<0)
4167 /* if filter is on top of stack (usual case) just pop it off */
4168 datasv = FILTER_DATA(AvFILLp(PL_rsfp_filters));
4169 if (IoANY(datasv) == FPTR2DPTR(void *, funcp)) {
4170 sv_free(av_pop(PL_rsfp_filters));
4174 /* we need to search for the correct entry and clear it */
4175 Perl_die(aTHX_ "filter_del can only delete in reverse order (currently)");
4179 /* Invoke the idxth filter function for the current rsfp. */
4180 /* maxlen 0 = read one text line */
4182 Perl_filter_read(pTHX_ int idx, SV *buf_sv, int maxlen)
4187 /* This API is bad. It should have been using unsigned int for maxlen.
4188 Not sure if we want to change the API, but if not we should sanity
4189 check the value here. */
4190 unsigned int correct_length
4199 PERL_ARGS_ASSERT_FILTER_READ;
4201 if (!PL_parser || !PL_rsfp_filters)
4203 if (idx > AvFILLp(PL_rsfp_filters)) { /* Any more filters? */
4204 /* Provide a default input filter to make life easy. */
4205 /* Note that we append to the line. This is handy. */
4206 DEBUG_P(PerlIO_printf(Perl_debug_log,
4207 "filter_read %d: from rsfp\n", idx));
4208 if (correct_length) {
4211 const int old_len = SvCUR(buf_sv);
4213 /* ensure buf_sv is large enough */
4214 SvGROW(buf_sv, (STRLEN)(old_len + correct_length + 1)) ;
4215 if ((len = PerlIO_read(PL_rsfp, SvPVX(buf_sv) + old_len,
4216 correct_length)) <= 0) {
4217 if (PerlIO_error(PL_rsfp))
4218 return -1; /* error */
4220 return 0 ; /* end of file */
4222 SvCUR_set(buf_sv, old_len + len) ;
4223 SvPVX(buf_sv)[old_len + len] = '\0';
4226 if (sv_gets(buf_sv, PL_rsfp, SvCUR(buf_sv)) == NULL) {
4227 if (PerlIO_error(PL_rsfp))
4228 return -1; /* error */
4230 return 0 ; /* end of file */
4233 return SvCUR(buf_sv);
4235 /* Skip this filter slot if filter has been deleted */
4236 if ( (datasv = FILTER_DATA(idx)) == &PL_sv_undef) {
4237 DEBUG_P(PerlIO_printf(Perl_debug_log,
4238 "filter_read %d: skipped (filter deleted)\n",
4240 return FILTER_READ(idx+1, buf_sv, correct_length); /* recurse */
4242 if (SvTYPE(datasv) != SVt_PVIO) {
4243 if (correct_length) {
4245 const STRLEN remainder = SvLEN(datasv) - SvCUR(datasv);
4246 if (!remainder) return 0; /* eof */
4247 if (correct_length > remainder) correct_length = remainder;
4248 sv_catpvn(buf_sv, SvEND(datasv), correct_length);
4249 SvCUR_set(datasv, SvCUR(datasv) + correct_length);
4252 const char *s = SvEND(datasv);
4253 const char *send = SvPVX(datasv) + SvLEN(datasv);
4261 if (s == send) return 0; /* eof */
4262 sv_catpvn(buf_sv, SvEND(datasv), s-SvEND(datasv));
4263 SvCUR_set(datasv, s-SvPVX(datasv));
4265 return SvCUR(buf_sv);
4267 /* Get function pointer hidden within datasv */
4268 funcp = DPTR2FPTR(filter_t, IoANY(datasv));
4269 DEBUG_P(PerlIO_printf(Perl_debug_log,
4270 "filter_read %d: via function %p (%s)\n",
4271 idx, (void*)datasv, SvPV_nolen_const(datasv)));
4272 /* Call function. The function is expected to */
4273 /* call "FILTER_READ(idx+1, buf_sv)" first. */
4274 /* Return: <0:error, =0:eof, >0:not eof */
4275 return (*funcp)(aTHX_ idx, buf_sv, correct_length);
4279 S_filter_gets(pTHX_ SV *sv, STRLEN append)
4283 PERL_ARGS_ASSERT_FILTER_GETS;
4285 #ifdef PERL_CR_FILTER
4286 if (!PL_rsfp_filters) {
4287 filter_add(S_cr_textfilter,NULL);
4290 if (PL_rsfp_filters) {
4292 SvCUR_set(sv, 0); /* start with empty line */
4293 if (FILTER_READ(0, sv, 0) > 0)
4294 return ( SvPVX(sv) ) ;
4299 return (sv_gets(sv, PL_rsfp, append));
4303 S_find_in_my_stash(pTHX_ const char *pkgname, STRLEN len)
4308 PERL_ARGS_ASSERT_FIND_IN_MY_STASH;
4310 if (len == 11 && *pkgname == '_' && strEQ(pkgname, "__PACKAGE__"))
4314 (pkgname[len - 2] == ':' && pkgname[len - 1] == ':') &&
4315 (gv = gv_fetchpvn_flags(pkgname, len, ( UTF ? SVf_UTF8 : 0 ), SVt_PVHV)))
4317 return GvHV(gv); /* Foo:: */
4320 /* use constant CLASS => 'MyClass' */
4321 gv = gv_fetchpvn_flags(pkgname, len, UTF ? SVf_UTF8 : 0, SVt_PVCV);
4322 if (gv && GvCV(gv)) {
4323 SV * const sv = cv_const_sv(GvCV(gv));
4325 pkgname = SvPV_const(sv, len);
4328 return gv_stashpvn(pkgname, len, UTF ? SVf_UTF8 : 0);
4332 * S_readpipe_override
4333 * Check whether readpipe() is overridden, and generates the appropriate
4334 * optree, provided sublex_start() is called afterwards.
4337 S_readpipe_override(pTHX)
4340 GV *gv_readpipe = gv_fetchpvs("readpipe", GV_NOTQUAL, SVt_PVCV);
4341 pl_yylval.ival = OP_BACKTICK;
4343 && GvCVu(gv_readpipe) && GvIMPORTED_CV(gv_readpipe))
4345 ((gvp = (GV**)hv_fetchs(PL_globalstash, "readpipe", FALSE))
4346 && (gv_readpipe = *gvp) && isGV_with_GP(gv_readpipe)
4347 && GvCVu(gv_readpipe) && GvIMPORTED_CV(gv_readpipe)))
4349 PL_lex_op = (OP*)newUNOP(OP_ENTERSUB, OPf_STACKED,
4350 op_append_elem(OP_LIST,
4351 newSVOP(OP_CONST, 0, &PL_sv_undef), /* value will be read later */
4352 newCVREF(0, newGVOP(OP_GV, 0, gv_readpipe))));
4359 * The intent of this yylex wrapper is to minimize the changes to the
4360 * tokener when we aren't interested in collecting madprops. It remains
4361 * to be seen how successful this strategy will be...
4368 char *s = PL_bufptr;
4370 /* make sure PL_thiswhite is initialized */
4374 /* previous token ate up our whitespace? */
4375 if (!PL_lasttoke && PL_nextwhite) {
4376 PL_thiswhite = PL_nextwhite;
4380 /* isolate the token, and figure out where it is without whitespace */
4381 PL_realtokenstart = -1;
4385 assert(PL_curforce < 0);
4387 if (!PL_thismad || PL_thismad->mad_key == '^') { /* not forced already? */
4388 if (!PL_thistoken) {
4389 if (PL_realtokenstart < 0 || !CopLINE(PL_curcop))
4390 PL_thistoken = newSVpvs("");
4392 char * const tstart = SvPVX(PL_linestr) + PL_realtokenstart;
4393 PL_thistoken = newSVpvn(tstart, s - tstart);
4396 if (PL_thismad) /* install head */
4397 CURMAD('X', PL_thistoken);
4400 /* last whitespace of a sublex? */
4401 if (optype == ')' && PL_endwhite) {
4402 CURMAD('X', PL_endwhite);
4407 /* if no whitespace and we're at EOF, bail. Otherwise fake EOF below. */
4408 if (!PL_thiswhite && !PL_endwhite && !optype) {
4409 sv_free(PL_thistoken);
4414 /* put off final whitespace till peg */
4415 if (optype == ';' && !PL_rsfp && !PL_parser->filtered) {
4416 PL_nextwhite = PL_thiswhite;
4419 else if (PL_thisopen) {
4420 CURMAD('q', PL_thisopen);
4422 sv_free(PL_thistoken);
4426 /* Store actual token text as madprop X */
4427 CURMAD('X', PL_thistoken);
4431 /* add preceding whitespace as madprop _ */
4432 CURMAD('_', PL_thiswhite);
4436 /* add quoted material as madprop = */
4437 CURMAD('=', PL_thisstuff);
4441 /* add terminating quote as madprop Q */
4442 CURMAD('Q', PL_thisclose);
4446 /* special processing based on optype */
4450 /* opval doesn't need a TOKEN since it can already store mp */
4460 if (pl_yylval.opval)
4461 append_madprops(PL_thismad, pl_yylval.opval, 0);