3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 * 2000, 2001, 2002, 2003, 2004, 2005 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 * The fields of BASEOP are:
13 * op_next Pointer to next ppcode to execute after this one.
14 * (Top level pre-grafted op points to first op,
15 * but this is replaced when op is grafted in, when
16 * this op will point to the real next op, and the new
17 * parent takes over role of remembering starting op.)
18 * op_ppaddr Pointer to current ppcode's function.
19 * op_type The type of the operation.
20 * op_opt Whether or not the op has been optimised by the
22 * op_static Whether or not the op is statically defined.
23 * This flag is used by the B::C compiler backend
24 * and indicates that the op should not be freed.
25 * op_latefree tell op_free() to clear this op (and free any kids)
26 * but not yet deallocate the struct. This means that
27 * the op may be safely op_free()d multiple times
28 * op_latefreed an op_latefree op has been op_free()d
29 * op_spare three spare bits!
30 * op_flags Flags common to all operations. See OPf_* below.
31 * op_private Flags peculiar to a particular operation (BUT,
32 * by default, set to the number of children until
33 * the operation is privatized by a check routine,
34 * which may or may not check number of children).
44 # define MADPROP_IN_BASEOP MADPROP* op_madprop;
46 # define MADPROP_IN_BASEOP
49 #ifdef BASEOP_DEFINITION
50 #define BASEOP BASEOP_DEFINITION
55 OP* (CPERLscope(*op_ppaddr))(pTHX); \
60 unsigned op_static:1; \
61 unsigned op_latefree:1; \
62 unsigned op_latefreed:1; \
63 unsigned op_spare:3; \
68 #define OP_GIMME(op,dfl) \
69 (((op)->op_flags & OPf_WANT) == OPf_WANT_VOID ? G_VOID : \
70 ((op)->op_flags & OPf_WANT) == OPf_WANT_SCALAR ? G_SCALAR : \
71 ((op)->op_flags & OPf_WANT) == OPf_WANT_LIST ? G_ARRAY : \
77 =for apidoc Amn|U32|GIMME_V
78 The XSUB-writer's equivalent to Perl's C<wantarray>. Returns C<G_VOID>,
79 C<G_SCALAR> or C<G_ARRAY> for void, scalar or list context,
82 =for apidoc Amn|U32|GIMME
83 A backward-compatible version of C<GIMME_V> which can only return
84 C<G_SCALAR> or C<G_ARRAY>; in a void context, it returns C<G_SCALAR>.
85 Deprecated. Use C<GIMME_V> instead.
90 #define GIMME_V OP_GIMME(PL_op, block_gimme())
94 #define OPf_WANT 3 /* Mask for "want" bits: */
95 #define OPf_WANT_VOID 1 /* Want nothing */
96 #define OPf_WANT_SCALAR 2 /* Want single value */
97 #define OPf_WANT_LIST 3 /* Want list of any length */
98 #define OPf_KIDS 4 /* There is a firstborn child. */
99 #define OPf_PARENS 8 /* This operator was parenthesized. */
100 /* (Or block needs explicit scope entry.) */
101 #define OPf_REF 16 /* Certified reference. */
102 /* (Return container, not containee). */
103 #define OPf_MOD 32 /* Will modify (lvalue). */
104 #define OPf_STACKED 64 /* Some arg is arriving on the stack. */
105 #define OPf_SPECIAL 128 /* Do something weird for this op: */
106 /* On local LVAL, don't init local value. */
107 /* On OP_SORT, subroutine is inlined. */
108 /* On OP_NOT, inversion was implicit. */
109 /* On OP_LEAVE, don't restore curpm. */
110 /* On truncate, we truncate filehandle */
111 /* On control verbs, we saw no label */
112 /* On flipflop, we saw ... instead of .. */
113 /* On UNOPs, saw bare parens, e.g. eof(). */
114 /* On OP_ENTERSUB || OP_NULL, saw a "do". */
115 /* On OP_EXISTS, treat av as av, not avhv. */
116 /* On OP_(ENTER|LEAVE)EVAL, don't clear $@ */
117 /* On OP_ENTERITER, loop var is per-thread */
118 /* On pushre, re is /\s+/ imp. by split " " */
119 /* On regcomp, "use re 'eval'" was in scope */
120 /* On OP_READLINE, was <$filehandle> */
121 /* On RV2[ACGHS]V, don't create GV--in
123 /* On OP_DBSTATE, indicates breakpoint
124 * (runtime property) */
125 /* On OP_AELEMFAST, indiciates pad var */
126 /* On OP_REQUIRE, was seen as CORE::require */
127 /* On OP_ENTERWHEN, there's no condition */
128 /* On OP_BREAK, an implicit break */
129 /* On OP_SMARTMATCH, an implicit smartmatch */
130 /* On OP_ANONHASH and OP_ANONLIST, create a
131 reference to the new anon hash or array */
133 /* old names; don't use in new code, but don't break them, either */
134 #define OPf_LIST OPf_WANT_LIST
135 #define OPf_KNOW OPf_WANT
138 (PL_op->op_flags & OPf_WANT \
139 ? ((PL_op->op_flags & OPf_WANT) == OPf_WANT_LIST \
144 /* NOTE: OP_NEXTSTATE, OP_DBSTATE, and OP_SETSTATE (i.e. COPs) carry lower
145 * bits of PL_hints in op_private */
147 /* Private for lvalues */
148 #define OPpLVAL_INTRO 128 /* Lvalue must be localized or lvalue sub */
150 /* Private for OP_LEAVE, OP_LEAVESUB, OP_LEAVESUBLV and OP_LEAVEWRITE */
151 #define OPpREFCOUNTED 64 /* op_targ carries a refcount */
153 /* Private for OP_AASSIGN */
154 #define OPpASSIGN_COMMON 64 /* Left & right have syms in common. */
156 /* Private for OP_SASSIGN */
157 #define OPpASSIGN_BACKWARDS 64 /* Left & right switched. */
158 #define OPpASSIGN_CV_TO_GV 128 /* Possible optimisation for constants. */
160 /* Private for OP_[AS]ASSIGN */
161 #define OPpASSIGN_STATE 32 /* Assign to a "state" variable */
163 /* Private for OP_MATCH and OP_SUBST{,CONST} */
164 #define OPpRUNTIME 64 /* Pattern coming in on the stack */
166 /* Private for OP_TRANS */
167 #define OPpTRANS_FROM_UTF 1
168 #define OPpTRANS_TO_UTF 2
169 #define OPpTRANS_IDENTICAL 4 /* right side is same as left */
170 #define OPpTRANS_SQUASH 8
171 /* 16 is used for OPpTARGET_MY */
172 #define OPpTRANS_COMPLEMENT 32
173 #define OPpTRANS_GROWS 64
174 #define OPpTRANS_DELETE 128
175 #define OPpTRANS_ALL (OPpTRANS_FROM_UTF|OPpTRANS_TO_UTF|OPpTRANS_IDENTICAL|OPpTRANS_SQUASH|OPpTRANS_COMPLEMENT|OPpTRANS_GROWS|OPpTRANS_DELETE)
177 /* Private for OP_REPEAT */
178 #define OPpREPEAT_DOLIST 64 /* List replication. */
180 /* Private for OP_RV2GV, OP_RV2SV, OP_AELEM, OP_HELEM, OP_PADSV */
181 #define OPpDEREF (32|64) /* autovivify: Want ref to something: */
182 #define OPpDEREF_AV 32 /* Want ref to AV. */
183 #define OPpDEREF_HV 64 /* Want ref to HV. */
184 #define OPpDEREF_SV (32|64) /* Want ref to SV. */
185 /* OP_ENTERSUB only */
186 #define OPpENTERSUB_DB 16 /* Debug subroutine. */
187 #define OPpENTERSUB_HASTARG 32 /* Called from OP tree. */
188 #define OPpENTERSUB_NOMOD 64 /* Immune to mod() for :attrlist. */
190 #define OPpENTERSUB_AMPER 8 /* Used & form to call. */
191 #define OPpENTERSUB_NOPAREN 128 /* bare sub call (without parens) */
192 #define OPpENTERSUB_INARGS 4 /* Lval used as arg to a sub. */
194 #define OPpEARLY_CV 32 /* foo() called before sub foo was parsed */
196 #define OPpLVAL_DEFER 16 /* Defer creation of array/hash elem */
197 /* OP_RV2?V, OP_GVSV, OP_ENTERITER only */
198 #define OPpOUR_INTRO 16 /* Variable was in an our() */
199 /* OP_RV2[AH]V, OP_PAD[AH]V, OP_[AH]ELEM */
200 #define OPpMAYBE_LVSUB 8 /* We might be an lvalue to return */
202 #define OPpPAD_STATE 16 /* is a "state" pad */
203 /* for OP_RV2?V, lower bits carry hints (currently only HINT_STRICT_REFS) */
206 #define OPpDONT_INIT_GV 8 /* Call gv_fetchpv with GV_NOINIT */
207 /* (Therefore will return whatever is currently in the symbol table, not
208 guaranteed to be a PVGV) */
211 #define OPpMAY_RETURN_CONSTANT 1 /* If a constant sub, return the constant */
213 /* Private for OPs with TARGLEX */
214 /* (lower bits may carry MAXARG) */
215 #define OPpTARGET_MY 16 /* Target is PADMY. */
217 /* Private for OP_ENTERITER and OP_ITER */
218 #define OPpITER_REVERSED 4 /* for (reverse ...) */
219 #define OPpITER_DEF 8 /* for $_ or for my $_ */
221 /* Private for OP_CONST */
222 #define OPpCONST_NOVER 2 /* no 6; */
223 #define OPpCONST_SHORTCIRCUIT 4 /* eg the constant 5 in (5 || foo) */
224 #define OPpCONST_STRICT 8 /* bearword subject to strict 'subs' */
225 #define OPpCONST_ENTERED 16 /* Has been entered as symbol. */
226 #define OPpCONST_ARYBASE 32 /* Was a $[ translated to constant. */
227 #define OPpCONST_BARE 64 /* Was a bare word (filehandle?). */
228 #define OPpCONST_WARNING 128 /* Was a $^W translated to constant. */
230 /* Private for OP_FLIP/FLOP */
231 #define OPpFLIP_LINENUM 64 /* Range arg potentially a line num. */
233 /* Private for OP_LIST */
234 #define OPpLIST_GUESSED 64 /* Guessed that pushmark was needed. */
236 /* Private for OP_DELETE */
237 #define OPpSLICE 64 /* Operating on a list of keys */
239 /* Private for OP_EXISTS */
240 #define OPpEXISTS_SUB 64 /* Checking for &sub, not {} or []. */
242 /* Private for OP_SORT */
243 #define OPpSORT_NUMERIC 1 /* Optimized away { $a <=> $b } */
244 #define OPpSORT_INTEGER 2 /* Ditto while under "use integer" */
245 #define OPpSORT_REVERSE 4 /* Reversed sort */
246 #define OPpSORT_INPLACE 8 /* sort in-place; eg @a = sort @a */
247 #define OPpSORT_DESCEND 16 /* Descending sort */
248 #define OPpSORT_QSORT 32 /* Use quicksort (not mergesort) */
249 #define OPpSORT_STABLE 64 /* Use a stable algorithm */
251 /* Private for OP_THREADSV */
252 #define OPpDONE_SVREF 64 /* Been through newSVREF once */
254 /* Private for OP_OPEN and OP_BACKTICK */
255 #define OPpOPEN_IN_RAW 16 /* binmode(F,":raw") on input fh */
256 #define OPpOPEN_IN_CRLF 32 /* binmode(F,":crlf") on input fh */
257 #define OPpOPEN_OUT_RAW 64 /* binmode(F,":raw") on output fh */
258 #define OPpOPEN_OUT_CRLF 128 /* binmode(F,":crlf") on output fh */
260 /* Private for OP_EXIT, HUSH also for OP_DIE */
261 #define OPpHUSH_VMSISH 64 /* hush DCL exit msg vmsish mode*/
262 #define OPpEXIT_VMSISH 128 /* exit(0) vs. exit(1) vmsish mode*/
264 /* Private for OP_FTXXX */
265 #define OPpFT_ACCESS 2 /* use filetest 'access' */
266 #define OPpFT_STACKED 4 /* stacked filetest, as in "-f -x $f" */
267 #define OP_IS_FILETEST_ACCESS(op) \
268 (((op)->op_type) == OP_FTRREAD || \
269 ((op)->op_type) == OP_FTRWRITE || \
270 ((op)->op_type) == OP_FTREXEC || \
271 ((op)->op_type) == OP_FTEREAD || \
272 ((op)->op_type) == OP_FTEWRITE || \
273 ((op)->op_type) == OP_FTEEXEC)
275 /* Private for OP_(MAP|GREP)(WHILE|START) */
276 #define OPpGREP_LEX 2 /* iterate over lexical $_ */
278 /* Private for OP_ENTEREVAL */
279 #define OPpEVAL_HAS_HH 2 /* Does it have a copy of %^H */
312 OP * op_pmreplroot; /* (type is really union {OP*,GV*,PADOFFSET}) */
314 PMOP * op_pmnext; /* list of all scanpats */
318 REGEXP * op_pmregexp; /* compiled expression */
331 #define PM_GETRE(o) (INT2PTR(REGEXP*,SvIVX(PL_regex_pad[(o)->op_pmoffset])))
332 #define PM_SETRE(o,r) STMT_START { \
333 SV* const sv = PL_regex_pad[(o)->op_pmoffset]; \
334 sv_setiv(sv, PTR2IV(r)); \
336 #define PM_GETRE_SAFE(o) (PL_regex_pad ? PM_GETRE(o) : (REGEXP*)0)
337 #define PM_SETRE_SAFE(o,r) if (PL_regex_pad) PM_SETRE(o,r)
339 #define PM_GETRE(o) ((o)->op_pmregexp)
340 #define PM_SETRE(o,r) ((o)->op_pmregexp = (r))
341 #define PM_GETRE_SAFE PM_GETRE
342 #define PM_SETRE_SAFE PM_SETRE
345 #define PMdf_USED 0x01 /* pm has been used once already */
346 #define PMdf_TAINTED 0x02 /* pm compiled from tainted pattern */
347 #define PMdf_UTF8 0x04 /* pm compiled from utf8 data */
348 #define PMdf_DYN_UTF8 0x08
350 #define PMdf_CMP_UTF8 (PMdf_UTF8|PMdf_DYN_UTF8)
352 #define PMf_RETAINT 0x0001 /* taint $1 etc. if target tainted */
353 #define PMf_ONCE 0x0002 /* use pattern only once per reset */
354 #define PMf_UNUSED 0x0004 /* free for use */
355 #define PMf_MAYBE_CONST 0x0008 /* replacement contains variables */
356 #define PMf_SKIPWHITE 0x0010 /* skip leading whitespace for split */
357 #define PMf_WHITE 0x0020 /* pattern is \s+ */
358 #define PMf_CONST 0x0040 /* subst replacement is constant */
359 #define PMf_KEEP 0x0080 /* keep 1st runtime pattern forever */
360 #define PMf_GLOBAL 0x0100 /* pattern had a g modifier */
361 #define PMf_CONTINUE 0x0200 /* don't reset pos() if //g fails */
362 #define PMf_EVAL 0x0400 /* evaluating replacement as expr */
363 #define PMf_LOCALE 0x0800 /* use locale for character types */
364 #define PMf_MULTILINE 0x1000 /* assume multiple lines */
365 #define PMf_SINGLELINE 0x2000 /* assume single line */
366 #define PMf_FOLD 0x4000 /* case insensitivity */
367 #define PMf_EXTENDED 0x8000 /* chuck embedded whitespace */
369 /* mask of bits stored in regexp->extflags
370 these all are also called RXf_PMf_xyz
372 #define PMf_COMPILETIME (PMf_MULTILINE|PMf_SINGLELINE|PMf_LOCALE|PMf_FOLD|PMf_EXTENDED)
376 # define PmopSTASHPV(o) ((o)->op_pmstashpv)
377 # define PmopSTASHPV_set(o,pv) (PmopSTASHPV(o) = savesharedpv(pv))
378 # define PmopSTASH(o) (PmopSTASHPV(o) \
379 ? gv_stashpv(PmopSTASHPV(o),GV_ADD) : NULL)
380 # define PmopSTASH_set(o,hv) PmopSTASHPV_set(o, ((hv) ? HvNAME_get(hv) : NULL))
381 # define PmopSTASH_free(o) PerlMemShared_free(PmopSTASHPV(o))
384 # define PmopSTASH(o) ((o)->op_pmstash)
385 # define PmopSTASH_set(o,hv) ((o)->op_pmstash = (hv))
386 # define PmopSTASHPV(o) (PmopSTASH(o) ? HvNAME_get(PmopSTASH(o)) : NULL)
387 /* op_pmstash is not refcounted */
388 # define PmopSTASHPV_set(o,pv) PmopSTASH_set((o), gv_stashpv(pv,GV_ADD))
389 # define PmopSTASH_free(o)
416 #define cUNOPx(o) ((UNOP*)o)
417 #define cBINOPx(o) ((BINOP*)o)
418 #define cLISTOPx(o) ((LISTOP*)o)
419 #define cLOGOPx(o) ((LOGOP*)o)
420 #define cPMOPx(o) ((PMOP*)o)
421 #define cSVOPx(o) ((SVOP*)o)
422 #define cPADOPx(o) ((PADOP*)o)
423 #define cPVOPx(o) ((PVOP*)o)
424 #define cCOPx(o) ((COP*)o)
425 #define cLOOPx(o) ((LOOP*)o)
427 #define cUNOP cUNOPx(PL_op)
428 #define cBINOP cBINOPx(PL_op)
429 #define cLISTOP cLISTOPx(PL_op)
430 #define cLOGOP cLOGOPx(PL_op)
431 #define cPMOP cPMOPx(PL_op)
432 #define cSVOP cSVOPx(PL_op)
433 #define cPADOP cPADOPx(PL_op)
434 #define cPVOP cPVOPx(PL_op)
435 #define cCOP cCOPx(PL_op)
436 #define cLOOP cLOOPx(PL_op)
438 #define cUNOPo cUNOPx(o)
439 #define cBINOPo cBINOPx(o)
440 #define cLISTOPo cLISTOPx(o)
441 #define cLOGOPo cLOGOPx(o)
442 #define cPMOPo cPMOPx(o)
443 #define cSVOPo cSVOPx(o)
444 #define cPADOPo cPADOPx(o)
445 #define cPVOPo cPVOPx(o)
446 #define cCOPo cCOPx(o)
447 #define cLOOPo cLOOPx(o)
449 #define kUNOP cUNOPx(kid)
450 #define kBINOP cBINOPx(kid)
451 #define kLISTOP cLISTOPx(kid)
452 #define kLOGOP cLOGOPx(kid)
453 #define kPMOP cPMOPx(kid)
454 #define kSVOP cSVOPx(kid)
455 #define kPADOP cPADOPx(kid)
456 #define kPVOP cPVOPx(kid)
457 #define kCOP cCOPx(kid)
458 #define kLOOP cLOOPx(kid)
462 # define cGVOPx_gv(o) ((GV*)PAD_SVl(cPADOPx(o)->op_padix))
463 # define IS_PADGV(v) (v && SvTYPE(v) == SVt_PVGV && GvIN_PAD(v))
464 # define IS_PADCONST(v) (v && SvREADONLY(v))
465 # define cSVOPx_sv(v) (cSVOPx(v)->op_sv \
466 ? cSVOPx(v)->op_sv : PAD_SVl((v)->op_targ))
467 # define cSVOPx_svp(v) (cSVOPx(v)->op_sv \
468 ? &cSVOPx(v)->op_sv : &PAD_SVl((v)->op_targ))
470 # define cGVOPx_gv(o) ((GV*)cSVOPx(o)->op_sv)
471 # define IS_PADGV(v) FALSE
472 # define IS_PADCONST(v) FALSE
473 # define cSVOPx_sv(v) (cSVOPx(v)->op_sv)
474 # define cSVOPx_svp(v) (&cSVOPx(v)->op_sv)
477 #define cGVOP_gv cGVOPx_gv(PL_op)
478 #define cGVOPo_gv cGVOPx_gv(o)
479 #define kGVOP_gv cGVOPx_gv(kid)
480 #define cSVOP_sv cSVOPx_sv(PL_op)
481 #define cSVOPo_sv cSVOPx_sv(o)
482 #define kSVOP_sv cSVOPx_sv(kid)
484 #define Nullop Null(OP*)
486 /* Lowest byte-and-a-bit of PL_opargs */
488 #define OA_FOLDCONST 2
489 #define OA_RETSCALAR 4
491 #define OA_RETINTEGER 16
492 #define OA_OTHERINT 32
493 #define OA_DANGEROUS 64
495 #define OA_TARGLEX 256
497 /* The next 4 bits encode op class information */
500 #define OA_CLASS_MASK (15 << OCSHIFT)
502 #define OA_BASEOP (0 << OCSHIFT)
503 #define OA_UNOP (1 << OCSHIFT)
504 #define OA_BINOP (2 << OCSHIFT)
505 #define OA_LOGOP (3 << OCSHIFT)
506 #define OA_LISTOP (4 << OCSHIFT)
507 #define OA_PMOP (5 << OCSHIFT)
508 #define OA_SVOP (6 << OCSHIFT)
509 #define OA_PADOP (7 << OCSHIFT)
510 #define OA_PVOP_OR_SVOP (8 << OCSHIFT)
511 #define OA_LOOP (9 << OCSHIFT)
512 #define OA_COP (10 << OCSHIFT)
513 #define OA_BASEOP_OR_UNOP (11 << OCSHIFT)
514 #define OA_FILESTATOP (12 << OCSHIFT)
515 #define OA_LOOPEXOP (13 << OCSHIFT)
519 /* Remaining nybbles of PL_opargs */
526 #define OA_SCALARREF 7
527 #define OA_OPTIONAL 8
529 /* Op_REFCNT is a reference count at the head of each op tree: needed
530 * since the tree is shared between threads, and between cloned closure
531 * copies in the same thread. OP_REFCNT_LOCK/UNLOCK is used when modifying
533 * The same mutex is used to protect the refcounts of the reg_trie_data
534 * and reg_ac_data structures, which are shared between duplicated
539 # define OP_REFCNT_INIT MUTEX_INIT(&PL_op_mutex)
541 # define OP_REFCNT_LOCK MUTEX_LOCK(&PL_op_mutex)
542 # define OP_REFCNT_UNLOCK MUTEX_UNLOCK(&PL_op_mutex)
544 # define OP_REFCNT_LOCK op_refcnt_lock()
545 # define OP_REFCNT_UNLOCK op_refcnt_unlock()
547 # define OP_REFCNT_TERM MUTEX_DESTROY(&PL_op_mutex)
549 # define OP_REFCNT_INIT NOOP
550 # define OP_REFCNT_LOCK NOOP
551 # define OP_REFCNT_UNLOCK NOOP
552 # define OP_REFCNT_TERM NOOP
555 #define OpREFCNT_set(o,n) ((o)->op_targ = (n))
556 #define OpREFCNT_inc(o) ((o) ? (++(o)->op_targ, (o)) : NULL)
557 #define OpREFCNT_dec(o) (--(o)->op_targ)
559 /* flags used by Perl_load_module() */
560 #define PERL_LOADMOD_DENY 0x1
561 #define PERL_LOADMOD_NOIMPORT 0x2
562 #define PERL_LOADMOD_IMPORT_OPS 0x4
564 #if defined(PERL_IN_PERLY_C) || defined(PERL_IN_OP_C)
565 #define ref(o, type) doref(o, type, TRUE)
568 /* no longer used anywhere in core */
570 #define cv_ckproto(cv, gv, p) cv_ckproto_len(cv, gv, p, p ? strlen(p) : 0)
573 #ifdef USE_REENTRANT_API
577 #if defined(PL_OP_SLAB_ALLOC)
578 #define NewOp(m,var,c,type) \
579 (var = (type *) Perl_Slab_Alloc(aTHX_ m,c*sizeof(type)))
580 #define NewOpSz(m,var,size) \
581 (var = (OP *) Perl_Slab_Alloc(aTHX_ m,size))
582 #define FreeOp(p) Perl_Slab_Free(aTHX_ p)
584 #define NewOp(m, var, c, type) \
585 (var = (MEM_WRAP_CHECK_(c,type) \
586 (type*)PerlMemShared_calloc(c, sizeof(type))))
587 #define NewOpSz(m, var, size) \
588 (var = (OP*)PerlMemShared_calloc(1, size))
589 #define FreeOp(p) PerlMemShared_free(p)
602 /* short mad_count; */
615 * Values that can be hold by mad_key :
616 * ^ unfilled head spot
618 * ; literal ; (blank if implicit ; at end of block)
619 * : literal : from ?: or attr list
621 * ? literal ? from ?:
631 * ! use is source filtered
633 * # whitespace/comment following ; or }
635 * 1 1st ; from for(;;)
637 * 2 2nd ; from for(;;)
640 * a sub or var attributes
641 * a non-method arrow operator
642 * A method arrow operator
645 * B retired stub block
646 * C constant conditional op
649 * e unreached "else" (see C)
650 * e expression producing E
652 * f folded constant op
653 * F peg op for format
654 * i if/unless modifier
655 * I if/elsif/unless statement
657 * l last index of array ($#foo)
659 * m modifier on regex
660 * M my assignment slurped into some other operator's target
661 * n sub or format name
662 * o current operator/declarator name
664 * O generic optimized op
665 * p peg to hold extra whitespace at statement level
666 * P peg op for package declaration
671 * r expression producing R
673 * R assign slurped by split
675 * S use import stub (no import)
676 * S retired sort block
677 * t unreached "then" (see C)
679 * v private sv of for loop
681 * w while/until modifier
682 * W while/for statement
685 * _ whitespace/comments preceding anything else