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a798dbf2 MB |
1 | # B.pm |
2 | # | |
1a52ab62 | 3 | # Copyright (c) 1996, 1997, 1998 Malcolm Beattie |
a798dbf2 MB |
4 | # |
5 | # You may distribute under the terms of either the GNU General Public | |
6 | # License or the Artistic License, as specified in the README file. | |
7 | # | |
8 | package B; | |
28b605d8 | 9 | |
744aaba0 | 10 | @B::ISA = qw(Exporter); |
b2590c4e | 11 | |
95d444af TR |
12 | # If B is loaded without imports, we do not want to unnecessarily pollute the stash with Exporter. |
13 | sub import { | |
14 | return unless scalar @_ > 1; # Called as a method call. | |
15 | require Exporter; | |
16 | B->export_to_level(1, @_); | |
17 | } | |
18 | ||
f72d64f0 DC |
19 | # walkoptree_slow comes from B.pm (you are there), |
20 | # walkoptree comes from B.xs | |
744aaba0 NC |
21 | |
22 | BEGIN { | |
948c7369 | 23 | $B::VERSION = '1.80'; |
4aa23ba6 | 24 | @B::EXPORT_OK = (); |
744aaba0 | 25 | |
4aa23ba6 NC |
26 | # Our BOOT code needs $VERSION set, and will append to @EXPORT_OK. |
27 | # Want our constants loaded before the compiler meets OPf_KIDS below, as | |
28 | # the combination of having the constant stay a Proxy Constant Subroutine | |
29 | # and its value being inlined saves a little over .5K | |
744aaba0 | 30 | |
744aaba0 NC |
31 | require XSLoader; |
32 | XSLoader::load(); | |
33 | } | |
34 | ||
4aa23ba6 NC |
35 | push @B::EXPORT_OK, (qw(minus_c ppname save_BEGINs |
36 | class peekop cast_I32 cstring cchar hash threadsv_names | |
37 | main_root main_start main_cv svref_2object opnumber | |
38 | sub_generation amagic_generation perlstring | |
39 | walkoptree_slow walkoptree walkoptree_exec walksymtable | |
40 | parents comppadlist sv_undef compile_stats timing_info | |
41 | begin_av init_av check_av end_av regex_padav dowarn | |
42 | defstash curstash warnhook diehook inc_gv @optype | |
d9cd2aeb | 43 | @specialsv_name unitcheck_av safename)); |
4aa23ba6 | 44 | |
a798dbf2 MB |
45 | @B::SV::ISA = 'B::OBJECT'; |
46 | @B::NULL::ISA = 'B::SV'; | |
47 | @B::PV::ISA = 'B::SV'; | |
48 | @B::IV::ISA = 'B::SV'; | |
4edc9001 | 49 | @B::NV::ISA = 'B::SV'; |
4df7f6af | 50 | # RV is eliminated with 5.11.0, but effectively is a specialisation of IV now. |
eb32218e | 51 | @B::RV::ISA = 'B::IV'; |
a798dbf2 | 52 | @B::PVIV::ISA = qw(B::PV B::IV); |
4edc9001 | 53 | @B::PVNV::ISA = qw(B::PVIV B::NV); |
a798dbf2 | 54 | @B::PVMG::ISA = 'B::PVNV'; |
eb32218e Z |
55 | @B::REGEXP::ISA = 'B::PVMG'; |
56 | @B::INVLIST::ISA = 'B::PV'; | |
35633035 DM |
57 | @B::PVLV::ISA = 'B::GV'; |
58 | @B::BM::ISA = 'B::GV'; | |
a798dbf2 MB |
59 | @B::AV::ISA = 'B::PVMG'; |
60 | @B::GV::ISA = 'B::PVMG'; | |
61 | @B::HV::ISA = 'B::PVMG'; | |
62 | @B::CV::ISA = 'B::PVMG'; | |
276493cb SM |
63 | @B::IO::ISA = 'B::PVMG'; |
64 | @B::FM::ISA = 'B::CV'; | |
a798dbf2 MB |
65 | |
66 | @B::OP::ISA = 'B::OBJECT'; | |
67 | @B::UNOP::ISA = 'B::OP'; | |
2f7c6295 | 68 | @B::UNOP_AUX::ISA = 'B::UNOP'; |
a798dbf2 MB |
69 | @B::BINOP::ISA = 'B::UNOP'; |
70 | @B::LOGOP::ISA = 'B::UNOP'; | |
a798dbf2 MB |
71 | @B::LISTOP::ISA = 'B::BINOP'; |
72 | @B::SVOP::ISA = 'B::OP'; | |
7934575e | 73 | @B::PADOP::ISA = 'B::OP'; |
a798dbf2 | 74 | @B::PVOP::ISA = 'B::OP'; |
a798dbf2 MB |
75 | @B::LOOP::ISA = 'B::LISTOP'; |
76 | @B::PMOP::ISA = 'B::LISTOP'; | |
77 | @B::COP::ISA = 'B::OP'; | |
b46e009d | 78 | @B::METHOP::ISA = 'B::OP'; |
a798dbf2 MB |
79 | |
80 | @B::SPECIAL::ISA = 'B::OBJECT'; | |
81 | ||
602bd5cc | 82 | our @optype = qw(OP UNOP BINOP LOGOP LISTOP PMOP SVOP PADOP PVOP LOOP COP |
2f7c6295 | 83 | METHOP UNOP_AUX); |
baccf54f NC |
84 | # bytecode.pl contained the following comment: |
85 | # Nullsv *must* come first in the following so that the condition | |
86 | # ($$sv == 0) can continue to be used to test (sv == Nullsv). | |
602bd5cc | 87 | our @specialsv_name = qw(Nullsv &PL_sv_undef &PL_sv_yes &PL_sv_no |
b043c4bf DM |
88 | (SV*)pWARN_ALL (SV*)pWARN_NONE (SV*)pWARN_STD |
89 | &PL_sv_zero); | |
baccf54f | 90 | |
a798dbf2 MB |
91 | { |
92 | # Stop "-w" from complaining about the lack of a real B::OBJECT class | |
93 | package B::OBJECT; | |
94 | } | |
95 | ||
002b978b | 96 | sub B::GV::SAFENAME { |
d9cd2aeb FC |
97 | safename(shift()->NAME); |
98 | } | |
99 | ||
100 | sub safename { | |
101 | my $name = shift; | |
d9963e60 RH |
102 | |
103 | # The regex below corresponds to the isCONTROLVAR macro | |
104 | # from toke.c | |
105 | ||
2bd1cbf6 KW |
106 | $name =~ s/^\c?/^?/ |
107 | or $name =~ s/^([\cA-\cZ\c\\c[\c]\c_\c^])/ | |
108 | "^" . chr( utf8::unicode_to_native( 64 ^ ord($1) ))/e; | |
7a9b44b9 RH |
109 | |
110 | # When we say unicode_to_native we really mean ascii_to_native, | |
2bd1cbf6 KW |
111 | # which matters iff this is a non-ASCII platform (EBCDIC). '\c?' would |
112 | # not have to be special cased, except for non-ASCII. | |
7a9b44b9 | 113 | |
002b978b RH |
114 | return $name; |
115 | } | |
116 | ||
d9963e60 RH |
117 | sub B::IV::int_value { |
118 | my ($self) = @_; | |
119 | return (($self->FLAGS() & SVf_IVisUV()) ? $self->UVX : $self->IV); | |
120 | } | |
121 | ||
f3402b25 | 122 | sub B::NULL::as_string() {""} |
602bd5cc TR |
123 | *B::IV::as_string = *B::IV::as_string = \*B::IV::int_value; |
124 | *B::PV::as_string = *B::PV::as_string = \*B::PV::PV; | |
f3402b25 | 125 | |
ff1a9fc0 NC |
126 | # The input typemap checking makes no distinction between different SV types, |
127 | # so the XS body will generate the same C code, despite the different XS | |
128 | # "types". So there is no change in behaviour from doing "newXS" like this, | |
129 | # compared with the old approach of having a (near) duplicate XS body. | |
130 | # We should fix the typemap checking. | |
602bd5cc TR |
131 | |
132 | # Since perl 5.12.0 | |
133 | *B::IV::RV = *B::IV::RV = \*B::PV::RV; | |
ff1a9fc0 | 134 | |
a798dbf2 MB |
135 | my $debug; |
136 | my $op_count = 0; | |
137 | my @parents = (); | |
138 | ||
139 | sub debug { | |
140 | my ($class, $value) = @_; | |
141 | $debug = $value; | |
142 | walkoptree_debug($value); | |
143 | } | |
144 | ||
a798dbf2 MB |
145 | sub class { |
146 | my $obj = shift; | |
147 | my $name = ref $obj; | |
148 | $name =~ s/^.*:://; | |
149 | return $name; | |
150 | } | |
151 | ||
152 | sub parents { \@parents } | |
153 | ||
154 | # For debugging | |
155 | sub peekop { | |
156 | my $op = shift; | |
3f872cb9 | 157 | return sprintf("%s (0x%x) %s", class($op), $$op, $op->name); |
a798dbf2 MB |
158 | } |
159 | ||
b2590c4e | 160 | sub walkoptree_slow { |
a798dbf2 MB |
161 | my($op, $method, $level) = @_; |
162 | $op_count++; # just for statistics | |
163 | $level ||= 0; | |
164 | warn(sprintf("walkoptree: %d. %s\n", $level, peekop($op))) if $debug; | |
156f89f0 | 165 | $op->$method($level) if $op->can($method); |
a798dbf2 MB |
166 | if ($$op && ($op->flags & OPf_KIDS)) { |
167 | my $kid; | |
168 | unshift(@parents, $op); | |
169 | for ($kid = $op->first; $$kid; $kid = $kid->sibling) { | |
b2590c4e | 170 | walkoptree_slow($kid, $method, $level + 1); |
a798dbf2 MB |
171 | } |
172 | shift @parents; | |
173 | } | |
156f89f0 JJ |
174 | if (class($op) eq 'PMOP' |
175 | && ref($op->pmreplroot) | |
176 | && ${$op->pmreplroot} | |
177 | && $op->pmreplroot->isa( 'B::OP' )) | |
178 | { | |
0091380b RGS |
179 | unshift(@parents, $op); |
180 | walkoptree_slow($op->pmreplroot, $method, $level + 1); | |
181 | shift @parents; | |
182 | } | |
a798dbf2 MB |
183 | } |
184 | ||
185 | sub compile_stats { | |
186 | return "Total number of OPs processed: $op_count\n"; | |
187 | } | |
188 | ||
189 | sub timing_info { | |
190 | my ($sec, $min, $hr) = localtime; | |
191 | my ($user, $sys) = times; | |
192 | sprintf("%02d:%02d:%02d user=$user sys=$sys", | |
193 | $hr, $min, $sec, $user, $sys); | |
194 | } | |
195 | ||
196 | my %symtable; | |
2b8dc4d2 DM |
197 | |
198 | sub clearsym { | |
199 | %symtable = (); | |
200 | } | |
201 | ||
a798dbf2 MB |
202 | sub savesym { |
203 | my ($obj, $value) = @_; | |
204 | # warn(sprintf("savesym: sym_%x => %s\n", $$obj, $value)); # debug | |
205 | $symtable{sprintf("sym_%x", $$obj)} = $value; | |
206 | } | |
207 | ||
208 | sub objsym { | |
209 | my $obj = shift; | |
210 | return $symtable{sprintf("sym_%x", $$obj)}; | |
211 | } | |
212 | ||
213 | sub walkoptree_exec { | |
214 | my ($op, $method, $level) = @_; | |
244826eb | 215 | $level ||= 0; |
a798dbf2 MB |
216 | my ($sym, $ppname); |
217 | my $prefix = " " x $level; | |
218 | for (; $$op; $op = $op->next) { | |
219 | $sym = objsym($op); | |
220 | if (defined($sym)) { | |
221 | print $prefix, "goto $sym\n"; | |
222 | return; | |
223 | } | |
224 | savesym($op, sprintf("%s (0x%lx)", class($op), $$op)); | |
225 | $op->$method($level); | |
3f872cb9 | 226 | $ppname = $op->name; |
1a67a97c | 227 | if ($ppname =~ |
62e36f8a | 228 | /^(d?or(assign)?|and(assign)?|mapwhile|grepwhile|entertry|range|cond_expr)$/) |
1a67a97c | 229 | { |
a798dbf2 MB |
230 | print $prefix, uc($1), " => {\n"; |
231 | walkoptree_exec($op->other, $method, $level + 1); | |
232 | print $prefix, "}\n"; | |
3f872cb9 | 233 | } elsif ($ppname eq "match" || $ppname eq "subst") { |
a798dbf2 MB |
234 | my $pmreplstart = $op->pmreplstart; |
235 | if ($$pmreplstart) { | |
236 | print $prefix, "PMREPLSTART => {\n"; | |
237 | walkoptree_exec($pmreplstart, $method, $level + 1); | |
238 | print $prefix, "}\n"; | |
239 | } | |
3f872cb9 | 240 | } elsif ($ppname eq "substcont") { |
a798dbf2 MB |
241 | print $prefix, "SUBSTCONT => {\n"; |
242 | walkoptree_exec($op->other->pmreplstart, $method, $level + 1); | |
243 | print $prefix, "}\n"; | |
244 | $op = $op->other; | |
3f872cb9 | 245 | } elsif ($ppname eq "enterloop") { |
a798dbf2 MB |
246 | print $prefix, "REDO => {\n"; |
247 | walkoptree_exec($op->redoop, $method, $level + 1); | |
248 | print $prefix, "}\n", $prefix, "NEXT => {\n"; | |
249 | walkoptree_exec($op->nextop, $method, $level + 1); | |
250 | print $prefix, "}\n", $prefix, "LAST => {\n"; | |
251 | walkoptree_exec($op->lastop, $method, $level + 1); | |
252 | print $prefix, "}\n"; | |
3f872cb9 | 253 | } elsif ($ppname eq "subst") { |
a798dbf2 MB |
254 | my $replstart = $op->pmreplstart; |
255 | if ($$replstart) { | |
256 | print $prefix, "SUBST => {\n"; | |
257 | walkoptree_exec($replstart, $method, $level + 1); | |
258 | print $prefix, "}\n"; | |
259 | } | |
260 | } | |
261 | } | |
262 | } | |
263 | ||
264 | sub walksymtable { | |
265 | my ($symref, $method, $recurse, $prefix) = @_; | |
266 | my $sym; | |
b6b0fb7b MB |
267 | my $fullname; |
268 | no strict 'refs'; | |
0cc1d052 | 269 | $prefix = '' unless defined $prefix; |
5cc8528c | 270 | foreach my $sym ( sort keys %$symref ) { |
f4a37198 FC |
271 | my $dummy = $symref->{$sym}; # Copying the glob and incrementing |
272 | # the GPs refcnt clears cached methods | |
b6b0fb7b | 273 | $fullname = "*main::".$prefix.$sym; |
a798dbf2 MB |
274 | if ($sym =~ /::$/) { |
275 | $sym = $prefix . $sym; | |
7834d9fb | 276 | if (svref_2object(\*$sym)->NAME ne "main::" && $sym ne "<none>::" && &$recurse($sym)) { |
b6b0fb7b | 277 | walksymtable(\%$fullname, $method, $recurse, $sym); |
a798dbf2 MB |
278 | } |
279 | } else { | |
b6b0fb7b | 280 | svref_2object(\*$fullname)->$method(); |
a798dbf2 MB |
281 | } |
282 | } | |
283 | } | |
284 | ||
a798dbf2 | 285 | 1; |
7f20e9dd GS |
286 | |
287 | __END__ | |
288 | ||
289 | =head1 NAME | |
290 | ||
4b661dd3 | 291 | B - The Perl Compiler Backend |
7f20e9dd GS |
292 | |
293 | =head1 SYNOPSIS | |
294 | ||
295 | use B; | |
296 | ||
297 | =head1 DESCRIPTION | |
298 | ||
1a52ab62 | 299 | The C<B> module supplies classes which allow a Perl program to delve |
130592f5 FC |
300 | into its own innards. It is the module used to implement the |
301 | "backends" of the Perl compiler. Usage of the compiler does not | |
1a52ab62 | 302 | require knowledge of this module: see the F<O> module for the |
130592f5 FC |
303 | user-visible part. The C<B> module is of use to those who want to |
304 | write new compiler backends. This documentation assumes that the | |
1a52ab62 MB |
305 | reader knows a fair amount about perl's internals including such |
306 | things as SVs, OPs and the internal symbol table and syntax tree | |
307 | of a program. | |
308 | ||
85cf7f2e MJD |
309 | =head1 OVERVIEW |
310 | ||
311 | The C<B> module contains a set of utility functions for querying the | |
312 | current state of the Perl interpreter; typically these functions | |
313 | return objects from the B::SV and B::OP classes, or their derived | |
314 | classes. These classes in turn define methods for querying the | |
315 | resulting objects about their own internal state. | |
316 | ||
317 | =head1 Utility Functions | |
318 | ||
319 | The C<B> module exports a variety of functions: some are simple | |
320 | utility functions, others provide a Perl program with a way to | |
321 | get an initial "handle" on an internal object. | |
322 | ||
323 | =head2 Functions Returning C<B::SV>, C<B::AV>, C<B::HV>, and C<B::CV> objects | |
324 | ||
3d036c2b | 325 | For descriptions of the class hierarchy of these objects and the |
85cf7f2e MJD |
326 | methods that can be called on them, see below, L<"OVERVIEW OF |
327 | CLASSES"> and L<"SV-RELATED CLASSES">. | |
328 | ||
329 | =over 4 | |
330 | ||
331 | =item sv_undef | |
332 | ||
333 | Returns the SV object corresponding to the C variable C<sv_undef>. | |
334 | ||
335 | =item sv_yes | |
336 | ||
337 | Returns the SV object corresponding to the C variable C<sv_yes>. | |
338 | ||
339 | =item sv_no | |
340 | ||
341 | Returns the SV object corresponding to the C variable C<sv_no>. | |
342 | ||
343 | =item svref_2object(SVREF) | |
344 | ||
345 | Takes a reference to any Perl value, and turns the referred-to value | |
346 | into an object in the appropriate B::OP-derived or B::SV-derived | |
130592f5 | 347 | class. Apart from functions such as C<main_root>, this is the primary |
85cf7f2e MJD |
348 | way to get an initial "handle" on an internal perl data structure |
349 | which can then be followed with the other access methods. | |
350 | ||
f31c3107 | 351 | The returned object will only be valid as long as the underlying OPs |
130592f5 | 352 | and SVs continue to exist. Do not attempt to use the object after the |
f31c3107 SM |
353 | underlying structures are freed. |
354 | ||
85cf7f2e MJD |
355 | =item amagic_generation |
356 | ||
357 | Returns the SV object corresponding to the C variable C<amagic_generation>. | |
66978156 FC |
358 | As of Perl 5.18, this is just an alias to C<PL_na>, so its value is |
359 | meaningless. | |
85cf7f2e | 360 | |
e13efe3c | 361 | =item init_av |
85cf7f2e MJD |
362 | |
363 | Returns the AV object (i.e. in class B::AV) representing INIT blocks. | |
364 | ||
ece599bd RGS |
365 | =item check_av |
366 | ||
367 | Returns the AV object (i.e. in class B::AV) representing CHECK blocks. | |
368 | ||
676456c2 AG |
369 | =item unitcheck_av |
370 | ||
371 | Returns the AV object (i.e. in class B::AV) representing UNITCHECK blocks. | |
372 | ||
85cf7f2e MJD |
373 | =item begin_av |
374 | ||
375 | Returns the AV object (i.e. in class B::AV) representing BEGIN blocks. | |
376 | ||
377 | =item end_av | |
378 | ||
379 | Returns the AV object (i.e. in class B::AV) representing END blocks. | |
380 | ||
381 | =item comppadlist | |
382 | ||
3a910aa0 FC |
383 | Returns the PADLIST object (i.e. in class B::PADLIST) of the global |
384 | comppadlist. In Perl 5.16 and earlier it returns an AV object (class | |
385 | B::AV). | |
85cf7f2e MJD |
386 | |
387 | =item regex_padav | |
388 | ||
389 | Only when perl was compiled with ithreads. | |
390 | ||
e13efe3c | 391 | =item main_cv |
85cf7f2e MJD |
392 | |
393 | Return the (faked) CV corresponding to the main part of the Perl | |
394 | program. | |
395 | ||
396 | =back | |
397 | ||
398 | =head2 Functions for Examining the Symbol Table | |
399 | ||
400 | =over 4 | |
401 | ||
402 | =item walksymtable(SYMREF, METHOD, RECURSE, PREFIX) | |
403 | ||
404 | Walk the symbol table starting at SYMREF and call METHOD on each | |
405 | symbol (a B::GV object) visited. When the walk reaches package | |
406 | symbols (such as "Foo::") it invokes RECURSE, passing in the symbol | |
407 | name, and only recurses into the package if that sub returns true. | |
408 | ||
409 | PREFIX is the name of the SYMREF you're walking. | |
410 | ||
411 | For example: | |
412 | ||
413 | # Walk CGI's symbol table calling print_subs on each symbol. | |
414 | # Recurse only into CGI::Util:: | |
26d2adad FC |
415 | walksymtable(\%CGI::, 'print_subs', |
416 | sub { $_[0] eq 'CGI::Util::' }, 'CGI::'); | |
85cf7f2e | 417 | |
130592f5 | 418 | print_subs() is a B::GV method you have declared. Also see L<"B::GV |
85cf7f2e MJD |
419 | Methods">, below. |
420 | ||
421 | =back | |
422 | ||
423 | =head2 Functions Returning C<B::OP> objects or for walking op trees | |
424 | ||
3d036c2b | 425 | For descriptions of the class hierarchy of these objects and the |
85cf7f2e MJD |
426 | methods that can be called on them, see below, L<"OVERVIEW OF |
427 | CLASSES"> and L<"OP-RELATED CLASSES">. | |
428 | ||
429 | =over 4 | |
430 | ||
431 | =item main_root | |
432 | ||
433 | Returns the root op (i.e. an object in the appropriate B::OP-derived | |
434 | class) of the main part of the Perl program. | |
435 | ||
436 | =item main_start | |
437 | ||
438 | Returns the starting op of the main part of the Perl program. | |
439 | ||
440 | =item walkoptree(OP, METHOD) | |
441 | ||
442 | Does a tree-walk of the syntax tree based at OP and calls METHOD on | |
130592f5 | 443 | each op it visits. Each node is visited before its children. If |
85cf7f2e MJD |
444 | C<walkoptree_debug> (see below) has been called to turn debugging on then |
445 | the method C<walkoptree_debug> is called on each op before METHOD is | |
446 | called. | |
447 | ||
448 | =item walkoptree_debug(DEBUG) | |
449 | ||
130592f5 FC |
450 | Returns the current debugging flag for C<walkoptree>. If the optional |
451 | DEBUG argument is non-zero, it sets the debugging flag to that. See | |
85cf7f2e MJD |
452 | the description of C<walkoptree> above for what the debugging flag |
453 | does. | |
454 | ||
455 | =back | |
456 | ||
457 | =head2 Miscellaneous Utility Functions | |
458 | ||
459 | =over 4 | |
460 | ||
461 | =item ppname(OPNUM) | |
462 | ||
463 | Return the PP function name (e.g. "pp_add") of op number OPNUM. | |
464 | ||
465 | =item hash(STR) | |
466 | ||
467 | Returns a string in the form "0x..." representing the value of the | |
468 | internal hash function used by perl on string STR. | |
469 | ||
470 | =item cast_I32(I) | |
471 | ||
472 | Casts I to the internal I32 type used by that perl. | |
473 | ||
474 | =item minus_c | |
475 | ||
130592f5 | 476 | Does the equivalent of the C<-c> command-line option. Obviously, this |
85cf7f2e MJD |
477 | is only useful in a BEGIN block or else the flag is set too late. |
478 | ||
479 | =item cstring(STR) | |
480 | ||
481 | Returns a double-quote-surrounded escaped version of STR which can | |
482 | be used as a string in C source code. | |
483 | ||
484 | =item perlstring(STR) | |
485 | ||
486 | Returns a double-quote-surrounded escaped version of STR which can | |
487 | be used as a string in Perl source code. | |
488 | ||
d9cd2aeb FC |
489 | =item safename(STR) |
490 | ||
491 | This function returns the string with the first character modified if it | |
492 | is a control character. It converts it to ^X format first, so that "\cG" | |
493 | becomes "^G". This is used internally by L<B::GV::SAFENAME|/SAFENAME>, but | |
494 | you can call it directly. | |
495 | ||
85cf7f2e MJD |
496 | =item class(OBJ) |
497 | ||
498 | Returns the class of an object without the part of the classname | |
130592f5 | 499 | preceding the first C<"::">. This is used to turn C<"B::UNOP"> into |
85cf7f2e MJD |
500 | C<"UNOP"> for example. |
501 | ||
502 | =item threadsv_names | |
503 | ||
dacd2ca7 DM |
504 | This used to provide support for the old 5.005 threading module. It now |
505 | does nothing. | |
85cf7f2e MJD |
506 | |
507 | =back | |
508 | ||
4082acab | 509 | =head2 Exported utility variables |
baccf54f NC |
510 | |
511 | =over 4 | |
512 | ||
513 | =item @optype | |
514 | ||
515 | my $op_type = $optype[$op_type_num]; | |
85cf7f2e | 516 | |
baccf54f NC |
517 | A simple mapping of the op type number to its type (like 'COP' or 'BINOP'). |
518 | ||
519 | =item @specialsv_name | |
520 | ||
521 | my $sv_name = $specialsv_name[$sv_index]; | |
522 | ||
523 | Certain SV types are considered 'special'. They're represented by | |
524 | B::SPECIAL and are referred to by a number from the specialsv_list. | |
525 | This array maps that number back to the name of the SV (like 'Nullsv' | |
526 | or '&PL_sv_undef'). | |
527 | ||
528 | =back | |
85cf7f2e MJD |
529 | |
530 | ||
1a52ab62 MB |
531 | =head1 OVERVIEW OF CLASSES |
532 | ||
533 | The C structures used by Perl's internals to hold SV and OP | |
534 | information (PVIV, AV, HV, ..., OP, SVOP, UNOP, ...) are modelled on a | |
535 | class hierarchy and the C<B> module gives access to them via a true | |
130592f5 | 536 | object hierarchy. Structure fields which point to other objects |
1a52ab62 | 537 | (whether types of SV or types of OP) are represented by the C<B> |
85cf7f2e MJD |
538 | module as Perl objects of the appropriate class. |
539 | ||
540 | The bulk of the C<B> module is the methods for accessing fields of | |
541 | these structures. | |
542 | ||
543 | Note that all access is read-only. You cannot modify the internals by | |
130592f5 | 544 | using this module. Also, note that the B::OP and B::SV objects created |
f31c3107 SM |
545 | by this module are only valid for as long as the underlying objects |
546 | exist; their creation doesn't increase the reference counts of the | |
130592f5 | 547 | underlying objects. Trying to access the fields of a freed object will |
f31c3107 | 548 | give incomprehensible results, or worse. |
1a52ab62 MB |
549 | |
550 | =head2 SV-RELATED CLASSES | |
551 | ||
eb32218e Z |
552 | B::IV, B::NV, B::PV, B::PVIV, B::PVNV, B::PVMG, |
553 | B::PVLV, B::AV, B::HV, B::CV, B::GV, B::FM, B::IO. These classes | |
6822775c | 554 | correspond in the obvious way to the underlying C structures of similar names. |
eb32218e | 555 | The inheritance hierarchy mimics the underlying C "inheritance": |
dda36756 NC |
556 | |
557 | B::SV | |
558 | | | |
559 | +------------+------------+ | |
560 | | | | | |
561 | B::PV B::IV B::NV | |
562 | \ / / | |
563 | \ / / | |
564 | B::PVIV / | |
565 | \ / | |
566 | \ / | |
567 | \ / | |
568 | B::PVNV | |
569 | | | |
570 | | | |
571 | B::PVMG | |
572 | | | |
573 | +-------+-------+---+---+-------+-------+ | |
574 | | | | | | | | |
575 | B::AV B::GV B::HV B::CV B::IO B::REGEXP | |
576 | | | | |
577 | | | | |
578 | B::PVLV B::FM | |
579 | ||
f5ba1307 | 580 | |
85cf7f2e | 581 | Access methods correspond to the underlying C macros for field access, |
1a52ab62 | 582 | usually with the leading "class indication" prefix removed (Sv, Av, |
130592f5 FC |
583 | Hv, ...). The leading prefix is only left in cases where its removal |
584 | would cause a clash in method name. For example, C<GvREFCNT> stays | |
1a52ab62 MB |
585 | as-is since its abbreviation would clash with the "superclass" method |
586 | C<REFCNT> (corresponding to the C function C<SvREFCNT>). | |
587 | ||
85cf7f2e | 588 | =head2 B::SV Methods |
1a52ab62 MB |
589 | |
590 | =over 4 | |
591 | ||
592 | =item REFCNT | |
593 | ||
594 | =item FLAGS | |
595 | ||
429a5ce7 SM |
596 | =item object_2svref |
597 | ||
598 | Returns a reference to the regular scalar corresponding to this | |
130592f5 FC |
599 | B::SV object. In other words, this method is the inverse operation |
600 | to the svref_2object() subroutine. This scalar and other data it points | |
429a5ce7 SM |
601 | at should be considered read-only: modifying them is neither safe nor |
602 | guaranteed to have a sensible effect. | |
603 | ||
1a52ab62 MB |
604 | =back |
605 | ||
85cf7f2e | 606 | =head2 B::IV Methods |
1a52ab62 MB |
607 | |
608 | =over 4 | |
609 | ||
610 | =item IV | |
611 | ||
d9963e60 | 612 | Returns the value of the IV, I<interpreted as |
130592f5 FC |
613 | a signed integer>. This will be misleading |
614 | if C<FLAGS & SVf_IVisUV>. Perhaps you want the | |
d9963e60 RH |
615 | C<int_value> method instead? |
616 | ||
1a52ab62 MB |
617 | =item IVX |
618 | ||
d9963e60 RH |
619 | =item UVX |
620 | ||
621 | =item int_value | |
622 | ||
623 | This method returns the value of the IV as an integer. | |
624 | It differs from C<IV> in that it returns the correct | |
625 | value regardless of whether it's stored signed or | |
626 | unsigned. | |
627 | ||
1a52ab62 MB |
628 | =item needs64bits |
629 | ||
630 | =item packiv | |
631 | ||
632 | =back | |
633 | ||
85cf7f2e | 634 | =head2 B::NV Methods |
1a52ab62 MB |
635 | |
636 | =over 4 | |
637 | ||
638 | =item NV | |
639 | ||
640 | =item NVX | |
641 | ||
43e81a9a FC |
642 | =item COP_SEQ_RANGE_LOW |
643 | ||
644 | =item COP_SEQ_RANGE_HIGH | |
645 | ||
dbac5ffe FC |
646 | These last two are only valid for pad name SVs. They only existed in the |
647 | B::NV class before Perl 5.22. In 5.22 they were moved to the B::PADNAME | |
648 | class. | |
43e81a9a | 649 | |
1a52ab62 MB |
650 | =back |
651 | ||
85cf7f2e | 652 | =head2 B::RV Methods |
1a52ab62 MB |
653 | |
654 | =over 4 | |
655 | ||
656 | =item RV | |
657 | ||
658 | =back | |
659 | ||
85cf7f2e | 660 | =head2 B::PV Methods |
1a52ab62 MB |
661 | |
662 | =over 4 | |
663 | ||
664 | =item PV | |
665 | ||
130592f5 | 666 | This method is the one you usually want. It constructs a |
76ef7183 JH |
667 | string using the length and offset information in the struct: |
668 | for ordinary scalars it will return the string that you'd see | |
669 | from Perl, even if it contains null characters. | |
670 | ||
9d2bbe64 MB |
671 | =item RV |
672 | ||
673 | Same as B::RV::RV, except that it will die() if the PV isn't | |
674 | a reference. | |
675 | ||
0b40bd6d RH |
676 | =item PVX |
677 | ||
130592f5 | 678 | This method is less often useful. It assumes that the string |
76ef7183 JH |
679 | stored in the struct is null-terminated, and disregards the |
680 | length information. | |
681 | ||
682 | It is the appropriate method to use if you need to get the name | |
130592f5 | 683 | of a lexical variable from a padname array. Lexical variable names |
76ef7183 | 684 | are always stored with a null terminator, and the length field |
5c140421 FC |
685 | (CUR) is overloaded for other purposes and can't be relied on here. |
686 | ||
687 | =item CUR | |
688 | ||
689 | This method returns the internal length field, which consists of the number | |
690 | of internal bytes, not necessarily the number of logical characters. | |
691 | ||
692 | =item LEN | |
693 | ||
694 | This method returns the number of bytes allocated (via malloc) for storing | |
695 | the string. This is 0 if the scalar does not "own" the string. | |
76ef7183 | 696 | |
1a52ab62 MB |
697 | =back |
698 | ||
85cf7f2e | 699 | =head2 B::PVMG Methods |
1a52ab62 MB |
700 | |
701 | =over 4 | |
702 | ||
703 | =item MAGIC | |
704 | ||
705 | =item SvSTASH | |
706 | ||
707 | =back | |
708 | ||
85cf7f2e | 709 | =head2 B::MAGIC Methods |
1a52ab62 MB |
710 | |
711 | =over 4 | |
712 | ||
713 | =item MOREMAGIC | |
714 | ||
9d2bbe64 MB |
715 | =item precomp |
716 | ||
717 | Only valid on r-magic, returns the string that generated the regexp. | |
718 | ||
1a52ab62 MB |
719 | =item PRIVATE |
720 | ||
721 | =item TYPE | |
722 | ||
723 | =item FLAGS | |
724 | ||
725 | =item OBJ | |
726 | ||
9d2bbe64 MB |
727 | Will die() if called on r-magic. |
728 | ||
1a52ab62 MB |
729 | =item PTR |
730 | ||
9d2bbe64 MB |
731 | =item REGEX |
732 | ||
733 | Only valid on r-magic, returns the integer value of the REGEX stored | |
734 | in the MAGIC. | |
735 | ||
1a52ab62 MB |
736 | =back |
737 | ||
85cf7f2e | 738 | =head2 B::PVLV Methods |
1a52ab62 MB |
739 | |
740 | =over 4 | |
741 | ||
742 | =item TARGOFF | |
743 | ||
744 | =item TARGLEN | |
745 | ||
746 | =item TYPE | |
747 | ||
748 | =item TARG | |
749 | ||
750 | =back | |
751 | ||
85cf7f2e | 752 | =head2 B::BM Methods |
1a52ab62 MB |
753 | |
754 | =over 4 | |
755 | ||
756 | =item USEFUL | |
757 | ||
758 | =item PREVIOUS | |
759 | ||
760 | =item RARE | |
761 | ||
762 | =item TABLE | |
763 | ||
764 | =back | |
765 | ||
3f03baed FC |
766 | =head2 B::REGEXP Methods |
767 | ||
768 | =over 4 | |
769 | ||
770 | =item REGEX | |
771 | ||
772 | =item precomp | |
773 | ||
6190dd99 FC |
774 | =item qr_anoncv |
775 | ||
1f306347 FC |
776 | =item compflags |
777 | ||
778 | The last two were added in Perl 5.22. | |
779 | ||
3f03baed FC |
780 | =back |
781 | ||
85cf7f2e | 782 | =head2 B::GV Methods |
1a52ab62 MB |
783 | |
784 | =over 4 | |
785 | ||
87d7fd28 GS |
786 | =item is_empty |
787 | ||
788 | This method returns TRUE if the GP field of the GV is NULL. | |
789 | ||
1a52ab62 MB |
790 | =item NAME |
791 | ||
002b978b RH |
792 | =item SAFENAME |
793 | ||
794 | This method returns the name of the glob, but if the first | |
795 | character of the name is a control character, then it converts | |
796 | it to ^X first, so that *^G would return "^G" rather than "\cG". | |
797 | ||
798 | It's useful if you want to print out the name of a variable. | |
799 | If you restrict yourself to globs which exist at compile-time | |
800 | then the result ought to be unambiguous, because code like | |
801 | C<${"^G"} = 1> is compiled as two ops - a constant string and | |
802 | a dereference (rv2gv) - so that the glob is created at runtime. | |
803 | ||
804 | If you're working with globs at runtime, and need to disambiguate | |
805 | *^G from *{"^G"}, then you should use the raw NAME method. | |
806 | ||
1a52ab62 MB |
807 | =item STASH |
808 | ||
809 | =item SV | |
810 | ||
811 | =item IO | |
812 | ||
813 | =item FORM | |
814 | ||
815 | =item AV | |
816 | ||
817 | =item HV | |
818 | ||
819 | =item EGV | |
820 | ||
821 | =item CV | |
822 | ||
823 | =item CVGEN | |
824 | ||
825 | =item LINE | |
826 | ||
b195d487 GS |
827 | =item FILE |
828 | ||
1a52ab62 MB |
829 | =item FILEGV |
830 | ||
831 | =item GvREFCNT | |
832 | ||
833 | =item FLAGS | |
834 | ||
8f4983af FC |
835 | =item GPFLAGS |
836 | ||
837 | This last one is present only in perl 5.22.0 and higher. | |
838 | ||
1a52ab62 MB |
839 | =back |
840 | ||
85cf7f2e | 841 | =head2 B::IO Methods |
1a52ab62 | 842 | |
8b858c71 FC |
843 | B::IO objects derive from IO objects and you will get more information from |
844 | the IO object itself. | |
44f7f2d5 RU |
845 | |
846 | For example: | |
847 | ||
848 | $gvio = B::svref_2object(\*main::stdin)->IO; | |
849 | $IO = $gvio->object_2svref(); | |
850 | $fd = $IO->fileno(); | |
851 | ||
1a52ab62 MB |
852 | =over 4 |
853 | ||
854 | =item LINES | |
855 | ||
856 | =item PAGE | |
857 | ||
858 | =item PAGE_LEN | |
859 | ||
860 | =item LINES_LEFT | |
861 | ||
862 | =item TOP_NAME | |
863 | ||
864 | =item TOP_GV | |
865 | ||
866 | =item FMT_NAME | |
867 | ||
868 | =item FMT_GV | |
869 | ||
870 | =item BOTTOM_NAME | |
871 | ||
872 | =item BOTTOM_GV | |
873 | ||
874 | =item SUBPROCESS | |
875 | ||
876 | =item IoTYPE | |
877 | ||
44f7f2d5 RU |
878 | A character symbolizing the type of IO Handle. |
879 | ||
880 | - STDIN/OUT | |
881 | I STDIN/OUT/ERR | |
882 | < read-only | |
883 | > write-only | |
884 | a append | |
885 | + read and write | |
886 | s socket | |
887 | | pipe | |
888 | I IMPLICIT | |
889 | # NUMERIC | |
890 | space closed handle | |
891 | \0 closed internal handle | |
892 | ||
1a52ab62 MB |
893 | =item IoFLAGS |
894 | ||
9d2bbe64 MB |
895 | =item IsSTD |
896 | ||
44f7f2d5 | 897 | Takes one argument ( 'stdin' | 'stdout' | 'stderr' ) and returns true |
9d2bbe64 | 898 | if the IoIFP of the object is equal to the handle whose name was |
8b858c71 | 899 | passed as argument; i.e., $io->IsSTD('stderr') is true if |
44f7f2d5 | 900 | IoIFP($io) == PerlIO_stderr(). |
9d2bbe64 | 901 | |
1a52ab62 MB |
902 | =back |
903 | ||
85cf7f2e | 904 | =head2 B::AV Methods |
1a52ab62 MB |
905 | |
906 | =over 4 | |
907 | ||
908 | =item FILL | |
909 | ||
910 | =item MAX | |
911 | ||
1a52ab62 MB |
912 | =item ARRAY |
913 | ||
429a5ce7 SM |
914 | =item ARRAYelt |
915 | ||
916 | Like C<ARRAY>, but takes an index as an argument to get only one element, | |
917 | rather than a list of all of them. | |
918 | ||
1a52ab62 MB |
919 | =back |
920 | ||
85cf7f2e | 921 | =head2 B::CV Methods |
1a52ab62 MB |
922 | |
923 | =over 4 | |
924 | ||
925 | =item STASH | |
926 | ||
927 | =item START | |
928 | ||
929 | =item ROOT | |
930 | ||
931 | =item GV | |
932 | ||
57843af0 GS |
933 | =item FILE |
934 | ||
1a52ab62 MB |
935 | =item DEPTH |
936 | ||
937 | =item PADLIST | |
938 | ||
eb32218e | 939 | Returns a B::PADLIST object. |
3a910aa0 | 940 | |
1a52ab62 MB |
941 | =item OUTSIDE |
942 | ||
a3985cdc DM |
943 | =item OUTSIDE_SEQ |
944 | ||
1a52ab62 MB |
945 | =item XSUB |
946 | ||
947 | =item XSUBANY | |
948 | ||
9d2bbe64 MB |
949 | For constant subroutines, returns the constant SV returned by the subroutine. |
950 | ||
5cfd8ad4 VB |
951 | =item CvFLAGS |
952 | ||
de3f1649 JT |
953 | =item const_sv |
954 | ||
486b1e7f TC |
955 | =item NAME_HEK |
956 | ||
957 | Returns the name of a lexical sub, otherwise C<undef>. | |
958 | ||
1a52ab62 MB |
959 | =back |
960 | ||
85cf7f2e | 961 | =head2 B::HV Methods |
1a52ab62 MB |
962 | |
963 | =over 4 | |
964 | ||
965 | =item FILL | |
966 | ||
967 | =item MAX | |
968 | ||
969 | =item KEYS | |
970 | ||
971 | =item RITER | |
972 | ||
973 | =item NAME | |
974 | ||
1a52ab62 MB |
975 | =item ARRAY |
976 | ||
977 | =back | |
978 | ||
979 | =head2 OP-RELATED CLASSES | |
980 | ||
2f7c6295 DM |
981 | C<B::OP>, C<B::UNOP>, C<B::UNOP_AUX>, C<B::BINOP>, C<B::LOGOP>, |
982 | C<B::LISTOP>, C<B::PMOP>, C<B::SVOP>, C<B::PADOP>, C<B::PVOP>, C<B::LOOP>, | |
983 | C<B::COP>, C<B::METHOP>. | |
85cf7f2e MJD |
984 | |
985 | These classes correspond in the obvious way to the underlying C | |
130592f5 | 986 | structures of similar names. The inheritance hierarchy mimics the |
85cf7f2e MJD |
987 | underlying C "inheritance": |
988 | ||
989 | B::OP | |
990 | | | |
b46e009d | 991 | +----------+---------+--------+-------+---------+ |
992 | | | | | | | | |
993 | B::UNOP B::SVOP B::PADOP B::COP B::PVOP B::METHOP | |
2f7c6295 DM |
994 | | |
995 | +---+---+---------+ | |
996 | | | | | |
997 | B::BINOP B::LOGOP B::UNOP_AUX | |
85cf7f2e MJD |
998 | | |
999 | | | |
1000 | B::LISTOP | |
2f7c6295 DM |
1001 | | |
1002 | +---+---+ | |
1003 | | | | |
1004 | B::LOOP B::PMOP | |
85cf7f2e | 1005 | |
b84c7839 | 1006 | Access methods correspond to the underlying C structure field names, |
85cf7f2e MJD |
1007 | with the leading "class indication" prefix (C<"op_">) removed. |
1008 | ||
1009 | =head2 B::OP Methods | |
1a52ab62 | 1010 | |
a60ba18b JC |
1011 | These methods get the values of similarly named fields within the OP |
1012 | data structure. See top of C<op.h> for more info. | |
1013 | ||
1a52ab62 MB |
1014 | =over 4 |
1015 | ||
1016 | =item next | |
1017 | ||
1018 | =item sibling | |
1019 | ||
29e61fd9 DM |
1020 | =item parent |
1021 | ||
1022 | Returns the OP's parent. If it has no parent, or if your perl wasn't built | |
1023 | with C<-DPERL_OP_PARENT>, returns NULL. | |
1024 | ||
c3890f9c DM |
1025 | Note that the global variable C<$B::OP::does_parent> is undefined on older |
1026 | perls that don't support the C<parent> method, is defined but false on | |
1027 | perls that support the method but were built without C<-DPERL_OP_PARENT>, | |
1028 | and is true otherwise. | |
1029 | ||
3f872cb9 GS |
1030 | =item name |
1031 | ||
1032 | This returns the op name as a string (e.g. "add", "rv2av"). | |
1033 | ||
1a52ab62 MB |
1034 | =item ppaddr |
1035 | ||
dc333d64 GS |
1036 | This returns the function name as a string (e.g. "PL_ppaddr[OP_ADD]", |
1037 | "PL_ppaddr[OP_RV2AV]"). | |
1a52ab62 MB |
1038 | |
1039 | =item desc | |
1040 | ||
4369b173 | 1041 | This returns the op description from the global C PL_op_desc array |
1a52ab62 MB |
1042 | (e.g. "addition" "array deref"). |
1043 | ||
1044 | =item targ | |
1045 | ||
1046 | =item type | |
1047 | ||
a60ba18b JC |
1048 | =item opt |
1049 | ||
1a52ab62 MB |
1050 | =item flags |
1051 | ||
1052 | =item private | |
1053 | ||
a60ba18b JC |
1054 | =item spare |
1055 | ||
1a52ab62 MB |
1056 | =back |
1057 | ||
18aceeb0 | 1058 | =head2 B::UNOP Method |
1a52ab62 MB |
1059 | |
1060 | =over 4 | |
1061 | ||
1062 | =item first | |
1063 | ||
1064 | =back | |
1065 | ||
18aceeb0 | 1066 | =head2 B::UNOP_AUX Methods (since 5.22) |
2f7c6295 DM |
1067 | |
1068 | =over 4 | |
1069 | ||
1070 | =item aux_list(cv) | |
1071 | ||
1072 | This returns a list of the elements of the op's aux data structure, | |
1073 | or a null list if there is no aux. What will be returned depends on the | |
1074 | object's type, but will typically be a collection of C<B::IV>, C<B::GV>, | |
1075 | etc. objects. C<cv> is the C<B::CV> object representing the sub that the | |
1076 | op is contained within. | |
1077 | ||
1078 | =item string(cv) | |
1079 | ||
1080 | This returns a textual representation of the object (likely to b useful | |
1081 | for deparsing and debugging), or an empty string if the op type doesn't | |
1082 | support this. C<cv> is the C<B::CV> object representing the sub that the | |
1083 | op is contained within. | |
1084 | ||
1085 | =back | |
1086 | ||
18aceeb0 | 1087 | =head2 B::BINOP Method |
1a52ab62 MB |
1088 | |
1089 | =over 4 | |
1090 | ||
1091 | =item last | |
1092 | ||
1093 | =back | |
1094 | ||
18aceeb0 | 1095 | =head2 B::LOGOP Method |
1a52ab62 MB |
1096 | |
1097 | =over 4 | |
1098 | ||
1099 | =item other | |
1100 | ||
1101 | =back | |
1102 | ||
18aceeb0 | 1103 | =head2 B::LISTOP Method |
1a52ab62 MB |
1104 | |
1105 | =over 4 | |
1106 | ||
1107 | =item children | |
1108 | ||
1109 | =back | |
1110 | ||
85cf7f2e | 1111 | =head2 B::PMOP Methods |
1a52ab62 MB |
1112 | |
1113 | =over 4 | |
1114 | ||
1115 | =item pmreplroot | |
1116 | ||
1117 | =item pmreplstart | |
1118 | ||
1a52ab62 MB |
1119 | =item pmflags |
1120 | ||
1a52ab62 MB |
1121 | =item precomp |
1122 | ||
651aa52e | 1123 | =item pmoffset |
9d2bbe64 MB |
1124 | |
1125 | Only when perl was compiled with ithreads. | |
1126 | ||
e07bb516 DM |
1127 | =item code_list |
1128 | ||
1129 | Since perl 5.17.1 | |
1130 | ||
429ba3b2 FC |
1131 | =item pmregexp |
1132 | ||
1133 | Added in perl 5.22, this method returns the B::REGEXP associated with the | |
1134 | op. While PMOPs do not actually have C<pmregexp> fields under threaded | |
1135 | builds, this method returns the regexp under threads nonetheless, for | |
1136 | convenience. | |
1137 | ||
1a52ab62 MB |
1138 | =back |
1139 | ||
18aceeb0 | 1140 | =head2 B::SVOP Methods |
1a52ab62 MB |
1141 | |
1142 | =over 4 | |
1143 | ||
1144 | =item sv | |
1145 | ||
065a1863 GS |
1146 | =item gv |
1147 | ||
1a52ab62 MB |
1148 | =back |
1149 | ||
18aceeb0 | 1150 | =head2 B::PADOP Method |
1a52ab62 MB |
1151 | |
1152 | =over 4 | |
1153 | ||
7934575e | 1154 | =item padix |
1a52ab62 MB |
1155 | |
1156 | =back | |
1157 | ||
18aceeb0 | 1158 | =head2 B::PVOP Method |
1a52ab62 MB |
1159 | |
1160 | =over 4 | |
1161 | ||
1162 | =item pv | |
1163 | ||
1164 | =back | |
1165 | ||
85cf7f2e | 1166 | =head2 B::LOOP Methods |
1a52ab62 MB |
1167 | |
1168 | =over 4 | |
1169 | ||
1170 | =item redoop | |
1171 | ||
1172 | =item nextop | |
1173 | ||
1174 | =item lastop | |
1175 | ||
1176 | =back | |
1177 | ||
85cf7f2e | 1178 | =head2 B::COP Methods |
1a52ab62 | 1179 | |
a379c8cb FC |
1180 | The C<B::COP> class is used for "nextstate" and "dbstate" ops. As of Perl |
1181 | 5.22, it is also used for "null" ops that started out as COPs. | |
1182 | ||
1a52ab62 MB |
1183 | =over 4 |
1184 | ||
1185 | =item label | |
1186 | ||
1187 | =item stash | |
1188 | ||
6e6a1aef RGS |
1189 | =item stashpv |
1190 | ||
a60c099b | 1191 | =item stashoff (threaded only) |
8df2993f | 1192 | |
57843af0 | 1193 | =item file |
1a52ab62 MB |
1194 | |
1195 | =item cop_seq | |
1196 | ||
1a52ab62 MB |
1197 | =item line |
1198 | ||
6e6a1aef RGS |
1199 | =item warnings |
1200 | ||
1201 | =item io | |
1202 | ||
d5ec2987 NC |
1203 | =item hints |
1204 | ||
b47e7f93 RGS |
1205 | =item hints_hash |
1206 | ||
1a52ab62 MB |
1207 | =back |
1208 | ||
b46e009d | 1209 | =head2 B::METHOP Methods (Since Perl 5.22) |
1210 | ||
1211 | =over 4 | |
1212 | ||
1213 | =item first | |
1214 | ||
1215 | =item meth_sv | |
1216 | ||
1217 | =back | |
1218 | ||
9b7476d7 | 1219 | =head2 PAD-RELATED CLASSES |
3a910aa0 | 1220 | |
9b7476d7 | 1221 | Perl 5.18 introduced a new class, B::PADLIST, returned by B::CV's |
3a910aa0 FC |
1222 | C<PADLIST> method. |
1223 | ||
9b7476d7 FC |
1224 | Perl 5.22 introduced the B::PADNAMELIST and B::PADNAME classes. |
1225 | ||
3a910aa0 FC |
1226 | =head2 B::PADLIST Methods |
1227 | ||
1228 | =over 4 | |
1229 | ||
1230 | =item MAX | |
1231 | ||
1232 | =item ARRAY | |
1233 | ||
eb32218e Z |
1234 | A list of pads. The first one is a B::PADNAMELIST containing the names. |
1235 | The rest are currently B::AV objects, but that could | |
9b7476d7 | 1236 | change in future versions. |
3a910aa0 FC |
1237 | |
1238 | =item ARRAYelt | |
1239 | ||
1240 | Like C<ARRAY>, but takes an index as an argument to get only one element, | |
1241 | rather than a list of all of them. | |
1242 | ||
9b7476d7 FC |
1243 | =item NAMES |
1244 | ||
1245 | This method, introduced in 5.22, returns the B::PADNAMELIST. It is | |
1246 | equivalent to C<ARRAYelt> with a 0 argument. | |
1247 | ||
1248 | =item REFCNT | |
1249 | ||
58480c3b FC |
1250 | =item id |
1251 | ||
1252 | This method, introduced in 5.22, returns an ID shared by clones of the same | |
1253 | padlist. | |
1254 | ||
1255 | =item outid | |
1256 | ||
1257 | This method, also added in 5.22, returns the ID of the outer padlist. | |
1258 | ||
9b7476d7 FC |
1259 | =back |
1260 | ||
1261 | =head2 B::PADNAMELIST Methods | |
1262 | ||
1263 | =over 4 | |
1264 | ||
1265 | =item MAX | |
1266 | ||
1267 | =item ARRAY | |
1268 | ||
1269 | =item ARRAYelt | |
1270 | ||
aa572f37 FC |
1271 | These two methods return the pad names, using B::SPECIAL objects for null |
1272 | pointers and B::PADNAME objects otherwise. | |
1273 | ||
3a910aa0 FC |
1274 | =item REFCNT |
1275 | ||
1276 | =back | |
7f20e9dd | 1277 | |
dbac5ffe FC |
1278 | =head2 B::PADNAME Methods |
1279 | ||
1280 | =over 4 | |
1281 | ||
1282 | =item PV | |
1283 | ||
1284 | =item PVX | |
1285 | ||
1286 | =item LEN | |
1287 | ||
1288 | =item REFCNT | |
1289 | ||
1290 | =item FLAGS | |
1291 | ||
1292 | For backward-compatibility, if the PADNAMEt_OUTER flag is set, the FLAGS | |
1293 | method adds the SVf_FAKE flag, too. | |
1294 | ||
1295 | =item TYPE | |
1296 | ||
1297 | A B::HV object representing the stash for a typed lexical. | |
1298 | ||
1299 | =item SvSTASH | |
1300 | ||
1301 | A backward-compatibility alias for TYPE. | |
1302 | ||
1303 | =item OURSTASH | |
1304 | ||
1305 | A B::HV object representing the stash for 'our' variables. | |
1306 | ||
1307 | =item PROTOCV | |
1308 | ||
1309 | The prototype CV for a 'my' sub. | |
1310 | ||
1311 | =item COP_SEQ_RANGE_LOW | |
1312 | ||
1313 | =item COP_SEQ_RANGE_HIGH | |
1314 | ||
1315 | Sequence numbers representing the scope within which a lexical is visible. | |
1316 | Meaningless if PADNAMEt_OUTER is set. | |
1317 | ||
1318 | =item PARENT_PAD_INDEX | |
1319 | ||
1320 | Only meaningful if PADNAMEt_OUTER is set. | |
1321 | ||
1322 | =item PARENT_FAKELEX_FLAGS | |
1323 | ||
1324 | Only meaningful if PADNAMEt_OUTER is set. | |
1325 | ||
1326 | =back | |
1327 | ||
71324a3b DM |
1328 | =head2 $B::overlay |
1329 | ||
1330 | Although the optree is read-only, there is an overlay facility that allows | |
1331 | you to override what values the various B::*OP methods return for a | |
1332 | particular op. C<$B::overlay> should be set to reference a two-deep hash: | |
1333 | indexed by OP address, then method name. Whenever a an op method is | |
1334 | called, the value in the hash is returned if it exists. This facility is | |
1335 | used by B::Deparse to "undo" some optimisations. For example: | |
1336 | ||
1337 | ||
1338 | local $B::overlay = {}; | |
1339 | ... | |
1340 | if ($op->name eq "foo") { | |
1341 | $B::overlay->{$$op} = { | |
1342 | name => 'bar', | |
1343 | next => $op->next->next, | |
1344 | }; | |
1345 | } | |
1346 | ... | |
1347 | $op->name # returns "bar" | |
1348 | $op->next # returns the next op but one | |
1349 | ||
1350 | ||
7f20e9dd GS |
1351 | =head1 AUTHOR |
1352 | ||
1353 | Malcolm Beattie, C<mbeattie@sable.ox.ac.uk> | |
1354 | ||
1355 | =cut |