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Assert valid op_private bits in op_free()
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1#!perl
2
3=head1 F<regen/op_private>
4
5This file contains all the definitions of the meanings of the flags in the
6op_private field of an OP.
7
8After editing this file, run C<make regen>. This will generate/update data
9in:
10
11 opcode.h
12 lib/B/Op_private.pm
13
14C<B::Op_private> holds three global hashes, C<%bits>, C<%defines>,
15C<%labels>, which hold roughly the same information as found in this file
16(after processing).
17
18F<opcode.h> gains a series of C<OPp*> defines, and a few static data
19structures:
20
21C<PL_op_private_valid> defines, per-op, which op_private bits are legally,
22allowed to be set. This is a first good place to look to see if an op has
23any spare private bits.
24
25C<PL_op_private_bitdef_ix>, C<PL_op_private_bitdefs>,
26C<PL_op_private_labels>, C<PL_op_private_bitfields>,
27C<PL_op_private_valid> contain (in a compact form) the data needed by
28Perl_do_op_dump() to dump the op_private field of an op.
29
30This file actually contains perl code which is run by F<regen/opcode.pl>.
31The basic idea is that you keep calling addbits() to add definitions of
32what a particular bit or range of bits in op_private means for a
33particular op. This can be specified either as a 1-bit flag or a 1-or-more
34bit bit field. Here's a general example:
35
36 addbits('aelem',
37 7 => qw(OPpLVAL_INTRO LVINTRO),
38 '5..6' => {
39 mask_def => 'OPpDEREF',
40 enum => [ qw(
41 1 OPpDEREF_AV DREFAV
42 2 OPpDEREF_HV DREFHV
43 3 OPpDEREF_SV DREFSV
44 )],
45 },
46 4 => qw(OPpLVAL_DEFER LVDEFER),
47 );
48
49Here for the op C<aelem>, bits 4 and 7 (bits are numbered 0..7) are
50defined as single-bit flags. The first string following the bit number is
51the define name that gets emitted in F<opcode.h>, and the second string is
52the label, which will be displayed by F<Concise.pm> and Perl_do_op_dump()
53(as used by C<perl -Dx>).
54
55If the bit number is actually two numbers connected with '..', then this
56defines a bit field, which is 1 or more bits taken to hold a small
57unsigned integer. Instead of two string arguments, it just has a single
58hash ref argument. A bit field allows you to generate extra defines, such
59as a mask, and optionally allows you to define an enumeration, where a
60subset of the possible values of the bit field are given their own defines
61and labels. The full syntax of this hash is explained further below.
62
63Note that not all bits for a particular op need to be added in a single
64addbits() call; they accumulate. In particular, this file is arranged in
65two halves; first, generic flags shared by multiple ops are added, then
66in the second half, specific per-op flags are added, e.g.
67
68 addbits($_, 7 => qw(OPpLVAL_INTRO LVINTRO)) for qw(pos substr vec ...);
69
70 ....
71
72 addbits('substr',
73 4 => qw(OPpSUBSTR_REPL_FIRST REPL1ST),
74 3 => ...
75 );
76
77(although the diving line between these two halves is somewhat subjective,
78and is based on whether "OPp" is followed by the op name or something
79generic).
80
81There are some utility functions for generating a list of ops from
82F<regen/opcodes> based on various criteria. These are:
83
84 ops_with_check('ck_foo')
85 ops_with_flag('X')
86 ops_with_arg(N, 'XYZ')
87
88which return a list of op names where:
89
90 field 3 of regen/opcodes specifies 'ck_foo' as the check function;
91 field 4 of of regen/opcodes has flag or type 'X' set;
92 argument field N of of regen/opcodes matches 'XYZ';
93
94For example
95
96 addbits($_, 4 => qw(OPpTARGET_MY TARGMY)) for ops_with_flag('T');
97
98If a label is specified as '-', then the flag or bit field is not
99displayed symbolically by Concise/-Dx; instead the bits are treated as
100unrecognised and included in the final residual integer value after all
101recognised bits have been processed (this doesn't apply to individual
102enum labels).
103
104Here is a full example of a bit field hash:
105
106 '5..6' => {
107 mask_def => 'OPpFOO_MASK',
108 baseshift_def => 'OPpFOO_SHIFT',
109 bitcount_def => 'OPpFOO_BITS',
110 label => 'FOO',
111 enum => [ qw(
112 1 OPpFOO_A A
113 2 OPpFOO_B B
114 3 OPpFOO_C C
115 )],
116 };
117
118The optional C<*_def> keys cause defines to be emitted that specify
119useful values based on the bit range (5 to 6 in this case):
120
121 mask_def: a mask that will extract the bit field
122 baseshift_def: how much to shift to make the bit field reach bit 0
123 bitcount_def: how many bits make up the bit field
124
125The example above will generate
126
127 #define OPpFOO_MASK 0x60
128 #define OPpFOO_SHIFT 5
129 #define OPpFOO_BITS 2
130
131The optional enum list specifies a set of defines and labels for (possibly
132a subset of) the possible values of the bit field (which in this example
133are 0,1,2,3). If a particular value matches an enum, then it will be
134displayed symbolically (e.g. 'C'), otherwise as a small integer. The
135defines are suitably shifted. The example above will generate
136
137 #define OPpFOO_A 0x20
138 #define OPpFOO_B 0x40
139 #define OPpFOO_C 0x60
140
141So you can write code like
142
143 if ((o->op_private & OPpFOO_MASK) == OPpFOO_C) ...
144
145The optional 'label' key causes Concise/-Dx output to prefix the value
146with C<LABEL=>; so in this case it might display C<FOO=C>. If the field
147value is zero, and if no label is present, and if no enum matches, then
148the field isn't displayed.
149
150=cut
151
152
153use warnings;
154use strict;
155
156
157
158
159# ====================================================================
160#
161# GENERIC OPpFOO flags
162#
163# Flags where FOO is a generic term (like LVAL), and the flag is
164# shared between multiple (possibly unrelated) ops.
165
166
167
168
169{
170 # The lower few bits of op_private often indicate the number of
171 # arguments. This is usually set by newUNOP() and newLOGOP (to 1),
172 # by newBINOP() (to 1 or 2), and by ck_fun() (to 1..15).
173 #
174 # These values are sometimes used at runtime: in particular,
175 # the MAXARG macro extracts out the lower 4 bits.
176 #
177 # Some ops encroach upon these bits; for example, entersub is a unop,
178 # but uses bit 0 for something else. Bit 0 is initially set to 1 in
179 # newUNOP(), but is later cleared (in ck_rvconst()), when the code
180 # notices that this op is an entersub.
181 #
182 # The important thing below is that any ops which use MAXARG at
183 # runtime must have all 4 bits allocated; if bit 3 were used for a new
184 # flag say, then things could break. The information on the other
185 # types of op is for completeness (so we can account for every bit
186 # used in every op)
187
188 my (%maxarg, %args0, %args1, %args2, %args3, %args4);
189
190 # these are the functions which currently use MAXARG at runtime
191 # (i.e. in the pp() functions). Thus they must always have 4 bits
192 # allocated
193 $maxarg{$_} = 1 for qw(
194 binmode bless caller chdir close enterwrite eof exit fileno getc
195 getpgrp gmtime index mkdir rand reset setpgrp sleep srand sysopen
196 tell umask
197 );
198
199 # find which ops use 0,1,2,3 or 4 bits of op_private for arg count info
200
201 $args0{$_} = 1 for qw(entersub); # UNOPs that usurp bit 0
202
203 $args1{$_} = 1 for (
204 qw(reverse), # ck_fun(), but most bits stolen
205 grep !$maxarg{$_} && !$args0{$_},
206 ops_with_flag('1'), # UNOP
207 ops_with_flag('%'), # BASEOP/UNOP
208 ops_with_flag('|'), # LOGOP
209 ops_with_flag('-'), # FILESTATOP
210 ops_with_flag('}'), # LOOPEXOP
211 );
212
213 $args2{$_} = 1 for (
214 qw(vec),
215 grep !$maxarg{$_} && !$args0{$_} && !$args1{$_},
216 ops_with_flag('2'), # BINOP
217 # this is a binop, but special-cased as a
218 # baseop in regen/opcodes
219 'sassign',
220 );
221
222 $args3{$_} = 1 for grep !$maxarg{$_} && !$args0{$_}
223 && !$args1{$_} && !$args2{$_},
224 # substr starts off with 4 bits set in
225 # ck_fun(), but since it never has more than 7
226 # args, bit 3 is later stolen
227 qw(substr);
228
229 $args4{$_} = 1 for keys %maxarg,
230 grep !$args0{$_} && !$args1{$_}
231 && !$args2{$_} && !$args3{$_},
232 ops_with_check('ck_fun'),
233 # these other ck_*() functions call ck_fun()
234 ops_with_check('ck_exec'),
235 ops_with_check('ck_glob'),
236 ops_with_check('ck_index'),
237 ops_with_check('ck_join'),
238 ops_with_check('ck_lfun'),
239 ops_with_check('ck_open'),
240 ops_with_check('ck_select'),
241 ops_with_check('ck_tell'),
242 ops_with_check('ck_trunc'),
243 ;
244
245
246 for (sort keys %args1) {
247 addbits($_, '0..0' => {
248 mask_def => 'OPpARG1_MASK',
249 label => '-',
250 }
251 );
252 }
253
254 for (sort keys %args2) {
255 addbits($_, '0..1' => {
256 mask_def => 'OPpARG2_MASK',
257 label => '-',
258 }
259 );
260 }
261
262 for (sort keys %args3) {
263 addbits($_, '0..2' => {
264 mask_def => 'OPpARG3_MASK',
265 label => '-',
266 }
267 );
268 }
269
270 for (sort keys %args4) {
271 addbits($_, '0..3' => {
272 mask_def => 'OPpARG4_MASK',
273 label => '-',
274 }
275 );
276 }
277}
278
279
280
281# if NATIVE_HINTS is defined, op_private on cops holds the top 8 bits
282# of PL_hints, although only bits 6 & 7 are officially used for that
283# purpose (the rest ought to be masked off). Bit 5 is set separately
284
285for (qw(nextstate dbstate)) {
286 addbits($_,
287 5 => qw(OPpHUSH_VMSISH HUSH),
288 # should match HINT_M_VMSISH_STATUS, HINT_M_VMSISH_TIME
289 6 => qw(OPpHINT_M_VMSISH_STATUS VMSISH_STATUS),
290 7 => qw(OPpHINT_M_VMSISH_TIME VMSISH_TIME),
291
292 );
293}
294
295
296
297addbits($_, 7 => qw(OPpLVAL_INTRO LVINTRO))
298 for qw(pos substr vec gvsv rv2sv rv2hv rv2gv rv2av aelem helem aslice
299 hslice delete padsv padav padhv enteriter entersub padrange
300 pushmark cond_expr),
301 'list', # this gets set in my_attrs() for some reason
302 ;
303
304
305
306# TARGLEX
307#
308# in constructs like my $x; ...; $x = $a + $b,
309# the sassign is optimised away and OPpTARGET_MY is set on the add op
310
311# XXX the old Concise.pm disagreed with regen/opcodes as to which ops have
312# this flag: in Concise, but not T:
313# bit_and bit_or bit_xor chop complement join negate postdec postinc
314# quotemeta schop sprintf
315# in T but not Concise:
316# srand
317
318addbits($_, 4 => qw(OPpTARGET_MY TARGMY))
319 for ops_with_flag('T'),
320 # This flag is also used to indicate matches against implicit $_,
321 # where $_ is lexical; e.g. my $_; ....; /foo/
322 qw(match subst trans transr);
323;
324
325
326
327
328
329# op_targ carries a refcount
330addbits($_, 6 => qw(OPpREFCOUNTED REFC))
331 for qw(leave leavesub leavesublv leavewrite leaveeval);
332
333
334
335# Do not copy return value
336addbits($_, 7 => qw(OPpLVALUE LV)) for qw(leave leaveloop);
337
338
339
340# Pattern coming in on the stack
341addbits($_, 6 => qw(OPpRUNTIME RTIME))
342 for qw(match subst substcont qr pushre);
343
344
345
346# autovivify: Want ref to something
347for (qw(rv2gv rv2sv padsv aelem helem entersub)) {
348 addbits($_, '5..6' => {
349 mask_def => 'OPpDEREF',
350 enum => [ qw(
351 1 OPpDEREF_AV DREFAV
352 2 OPpDEREF_HV DREFHV
353 3 OPpDEREF_SV DREFSV
354 )],
355 }
356 );
357}
358
359
360
361# Defer creation of array/hash elem
362addbits($_, 4 => qw(OPpLVAL_DEFER LVDEFER)) for qw(aelem helem);
363
364
365
366addbits($_, 2 => qw(OPpSLICEWARNING SLICEWARN)) # warn about @hash{$scalar}
367 for qw(rv2hv rv2av padav padhv hslice aslice);
368
369
370
371# XXX Concise seemed to think that OPpOUR_INTRO is used in rv2gv too,
372# but I can't see it - DAPM
373addbits($_, 4 => qw(OPpOUR_INTRO OURINTR)) # Variable was in an our()
374 for qw(gvsv rv2sv rv2av rv2hv enteriter);
375
376
377
378# We might be an lvalue to return
379addbits($_, 3 => qw(OPpMAYBE_LVSUB LVSUB))
380 for qw(aassign rv2av rv2gv rv2hv padav padhv aelem helem aslice hslice
381 av2arylen keys rkeys kvaslice kvhslice substr pos vec);
382
383
384
385for (qw(rv2hv padhv)) {
386 addbits($_, # e.g. %hash in (%hash || $foo) ...
387 5 => qw(OPpTRUEBOOL BOOL), # ... in void cxt
388 6 => qw(OPpMAYBE_TRUEBOOL BOOL?), # ... cx not known till run time
389 );
390}
391
392
393
394addbits($_, 1 => qw(OPpHINT_STRICT_REFS -)) for qw(rv2sv rv2av rv2hv rv2gv);
395
396
397
398# Treat caller(1) as caller(2)
399addbits($_, 7 => qw(OPpOFFBYONE +1)) for qw(caller wantarray runcv);
400
401
402
403# label is in UTF8 */
404addbits($_, 7 => qw(OPpPV_IS_UTF8 UTF)) for qw(last redo next goto dump);
405
406
407
408# ====================================================================
409#
410# OP-SPECIFIC OPpFOO_* flags:
411#
412# where FOO is typically the name of an op, and the flag is used by a
413# single op (or maybe by a few closely related ops).
414
415
416
417addbits($_, 4 => qw(OPpPAD_STATE STATE)) for qw(padav padhv padsv pushmark);
418
419
420
421addbits('aassign', 6 => qw(OPpASSIGN_COMMON COMMON));
422
423
424
425addbits('sassign',
426 6 => qw(OPpASSIGN_BACKWARDS BKWARD), # Left & right switched
427 7 => qw(OPpASSIGN_CV_TO_GV CV2GV), # Possible optimisation for constants
428);
429
430
431
432for (qw(trans transr)) {
433 addbits($_,
434 0 => qw(OPpTRANS_FROM_UTF <UTF),
435 1 => qw(OPpTRANS_TO_UTF >UTF),
436 2 => qw(OPpTRANS_IDENTICAL IDENT), # right side is same as left
437 3 => qw(OPpTRANS_SQUASH SQUASH),
438 # 4 is used for OPpTARGET_MY
439 5 => qw(OPpTRANS_COMPLEMENT COMPL),
440 6 => qw(OPpTRANS_GROWS GROWS),
441 7 => qw(OPpTRANS_DELETE DEL),
442 );
443}
444
445
446
447addbits('repeat', 6 => qw(OPpREPEAT_DOLIST DOLIST)); # List replication
448
449
450
451# OP_ENTERSUB and OP_RV2CV flags
452#
453# Flags are set on entersub and rv2cv in three phases:
454# parser - the parser passes the flag to the op constructor
455# check - the check routine called by the op constructor sets the flag
456# context - application of scalar/ref/lvalue context applies the flag
457#
458# In the third stage, an entersub op might turn into an rv2cv op (undef &foo,
459# \&foo, lock &foo, exists &foo, defined &foo). The two places where that
460# happens (op_lvalue_flags and doref in op.c) need to make sure the flags do
461# not conflict, since some flags with different meanings overlap between
462# the two ops. Flags applied in the context phase are only set when there
463# is no conversion of op type.
464#
465# bit entersub flag phase rv2cv flag phase
466# --- ------------- ----- ---------- -----
467# 0 OPpENTERSUB_INARGS context
468# 1 HINT_STRICT_REFS check HINT_STRICT_REFS check
469# 2 OPpENTERSUB_HASTARG check
470# 3 OPpENTERSUB_AMPER check OPpENTERSUB_AMPER parser
471# 4 OPpENTERSUB_DB check
472# 5 OPpDEREF_AV context
473# 6 OPpDEREF_HV context OPpMAY_RETURN_CONSTANT context
474# 7 OPpLVAL_INTRO context OPpENTERSUB_NOPAREN parser
475
476# NB: OPpHINT_STRICT_REFS must equal HINT_STRICT_REFS
477
478addbits('entersub',
479 0 => qw(OPpENTERSUB_INARGS INARGS), # Lval used as arg to a sub
480 1 => qw(OPpHINT_STRICT_REFS - ), # 'use strict' in scope
481 2 => qw(OPpENTERSUB_HASTARG TARG ), # Called from OP tree
482 3 => qw(OPpENTERSUB_AMPER AMPER), # Used & form to call
483 4 => qw(OPpENTERSUB_DB DBG ), # Debug subroutine
484 # 5..6 => OPpDEREF, already defined above
485 # 7 => OPpLVAL_INTRO, already defined above
486);
487addbits('rv2cv',
488 # If a constant sub, return the constant
489 1 => qw(OPpHINT_STRICT_REFS - ), # 'use strict' in scope
490
491 3 => qw(OPpENTERSUB_AMPER AMPER), # Used & form to call
492
493 6 => qw(OPpMAY_RETURN_CONSTANT CONST),
494 7 => qw(OPpENTERSUB_NOPAREN NO() ), # bare sub call (without parens)
495);
496
497# XXX perhaps ought the clear these flags in Perl_doref when converting
498# and entersub into an rv2cv???? Failing that, update the comments above
499# and add them as part of the main addbits('rv2cv'.
500
501addbits('rv2cv',
502 # If a constant sub, return the constant
503 2 => qw(OPpENTERSUB_HASTARG TARG),
504 4 => qw(OPpENTERSUB_DB DBG ), # Debug subroutine
505);
506
507
508
509#foo() called before sub foo was parsed */
510addbits('gv', 5 => qw(OPpEARLY_CV EARLYCV));
511
512
513
514# 1st arg is replacement string */
515addbits('substr', 4 => qw(OPpSUBSTR_REPL_FIRST REPL1ST));
516
517
518
519addbits('padrange',
520 # bits 0..6 hold target range
521 '0..6' => {
522 label => '-',
523 mask_def => 'OPpPADRANGE_COUNTMASK',
524 bitcount_def => 'OPpPADRANGE_COUNTSHIFT',
525 }
526 # 7 => OPpLVAL_INTRO, already defined above
527);
528
529
530
531for (qw(aelemfast aelemfast_lex)) {
532 addbits($_,
533 '0..7' => {
534 label => '-',
535 }
536 );
537}
538
539
540
541addbits('rv2gv',
542 2 => qw(OPpDONT_INIT_GV NOINIT), # Call gv_fetchpv with GV_NOINIT
543 # (Therefore will return whatever is currently in
544 # the symbol table, not guaranteed to be a PVGV)
545 4 => qw(OPpALLOW_FAKE FAKE), # OK to return fake glob
546);
547
548
549
550addbits('enteriter',
551 2 => qw(OPpITER_REVERSED REVERSED),# for (reverse ...)
552 3 => qw(OPpITER_DEF -), # 'for $_' or 'for my $_'
553);
554addbits('iter', 2 => qw(OPpITER_REVERSED REVERSED));
555
556
557
558addbits('const',
559 1 => qw(OPpCONST_NOVER NOVER), # no 6;
560 2 => qw(OPpCONST_SHORTCIRCUIT SHORT), # e.g. the constant 5 in (5 || foo)
561 3 => qw(OPpCONST_STRICT STRICT), # bareword subject to strict 'subs'
562 4 => qw(OPpCONST_ENTERED ENTERED), # Has been entered as symbol
563 6 => qw(OPpCONST_BARE BARE), # Was a bare word (filehandle?)
564);
565
566
567
568# Range arg potentially a line num. */
569addbits($_, 6 => qw(OPpFLIP_LINENUM LINENUM)) for qw(flip flop);
570
571
572
573# Guessed that pushmark was needed. */
574addbits('list', 6 => qw(OPpLIST_GUESSED GUESSED));
575
576
577
578# Operating on a list of keys
579addbits('delete', 6 => qw(OPpSLICE SLICE));
580# also 7 => OPpLVAL_INTRO, already defined above
581
582
583
584# Checking for &sub, not {} or [].
585addbits('exists', 6 => qw(OPpEXISTS_SUB SUB));
586
587
588
589addbits('sort',
590 0 => qw(OPpSORT_NUMERIC NUM ), # Optimized away { $a <=> $b }
591 1 => qw(OPpSORT_INTEGER INT ), # Ditto while under "use integer"
592 2 => qw(OPpSORT_REVERSE REV ), # Reversed sort
593 3 => qw(OPpSORT_INPLACE INPLACE), # sort in-place; eg @a = sort @a
594 4 => qw(OPpSORT_DESCEND DESC ), # Descending sort
595 5 => qw(OPpSORT_QSORT QSORT ), # Use quicksort (not mergesort)
596 6 => qw(OPpSORT_STABLE STABLE ), # Use a stable algorithm
597);
598
599
600
601# reverse in-place (@a = reverse @a) */
602addbits('reverse', 3 => qw(OPpREVERSE_INPLACE INPLACE));
603
604
605
606for (qw(open backtick)) {
607 addbits($_,
608 4 => qw(OPpOPEN_IN_RAW INBIN ), # binmode(F,":raw") on input fh
609 5 => qw(OPpOPEN_IN_CRLF INCR ), # binmode(F,":crlf") on input fh
610 6 => qw(OPpOPEN_OUT_RAW OUTBIN), # binmode(F,":raw") on output fh
611 7 => qw(OPpOPEN_OUT_CRLF OUTCR ), # binmode(F,":crlf") on output fh
612 );
613}
614
615
616
617# The various OPpFT* filetest ops
618
619# "use filetest 'access'" is in scope:
620# this flag is set only on a subset of the FT* ops
621addbits($_, 1 => qw(OPpFT_ACCESS FTACCESS)) for ops_with_arg(0, 'F-+');
622
623# all OPpFT* ops except stat and lstat
624for (grep { $_ !~ /^l?stat$/ } ops_with_flag('-')) {
625 addbits($_,
626 2 => qw(OPpFT_STACKED FTSTACKED ), # stacked filetest,
627 # e.g. "-f" in "-f -x $foo"
628 3 => qw(OPpFT_STACKING FTSTACKING), # stacking filetest.
629 # e.g. "-x" in "-f -x $foo"
630 4 => qw(OPpFT_AFTER_t FTAFTERt ), # previous op was -t
631 );
632}
633
634
635
636addbits($_, 1 => qw(OPpGREP_LEX GREPLEX)) # iterate over lexical $_
637 for qw(mapwhile mapstart grepwhile grepstart);
638
639
640
641addbits('entereval',
642 1 => qw(OPpEVAL_HAS_HH HAS_HH ), # Does it have a copy of %^H ?
643 2 => qw(OPpEVAL_UNICODE UNI ),
644 3 => qw(OPpEVAL_BYTES BYTES ),
645 4 => qw(OPpEVAL_COPHH COPHH ), # Construct %^H from COP hints
646 5 => qw(OPpEVAL_RE_REPARSING - ), # eval_sv(..., G_RE_REPARSING)
647);
648
649
650
651# These must not conflict with OPpDONT_INIT_GV or OPpALLOW_FAKE.
652# See pp.c:S_rv2gv. */
653addbits('coreargs',
654 0 => qw(OPpCOREARGS_DEREF1 DEREF1), # Arg 1 is a handle constructor
655 1 => qw(OPpCOREARGS_DEREF2 DEREF2), # Arg 2 is a handle constructor
656 #2 reserved for OPpDONT_INIT_GV in rv2gv
657 #4 reserved for OPpALLOW_FAKE in rv2gv
658 6 => qw(OPpCOREARGS_SCALARMOD $MOD ), # \$ rather than \[$@%*]
659 7 => qw(OPpCOREARGS_PUSHMARK MARK ), # Call pp_pushmark
660);
661
662
663
664addbits('split', 7 => qw(OPpSPLIT_IMPLIM IMPLIM)); # implicit limit
665
6661;
667
668# ex: set ts=8 sts=4 sw=4 et: