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a798dbf2 |
1 | # B.pm |
2 | # |
1a52ab62 |
3 | # Copyright (c) 1996, 1997, 1998 Malcolm Beattie |
a798dbf2 |
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 | |
6822775c |
10 | our $VERSION = '1.17'; |
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11 | |
9426adcd |
12 | use XSLoader (); |
a798dbf2 |
13 | require Exporter; |
9426adcd |
14 | @ISA = qw(Exporter); |
b2590c4e |
15 | |
f72d64f0 |
16 | # walkoptree_slow comes from B.pm (you are there), |
17 | # walkoptree comes from B.xs |
f6c2d85b |
18 | @EXPORT_OK = qw(minus_c ppname save_BEGINs |
19 | class peekop cast_I32 cstring cchar hash threadsv_names |
b2590c4e |
20 | main_root main_start main_cv svref_2object opnumber |
5ce57cc0 |
21 | sub_generation amagic_generation perlstring |
f6c2d85b |
22 | walkoptree_slow walkoptree walkoptree_exec walksymtable |
23 | parents comppadlist sv_undef compile_stats timing_info |
e412117e |
24 | begin_av init_av check_av end_av regex_padav dowarn defstash |
baccf54f |
25 | curstash warnhook diehook inc_gv @optype @specialsv_name |
651aa52e |
26 | ); |
e412117e |
27 | push @EXPORT_OK, qw(unitcheck_av) if $] > 5.009; |
b2590c4e |
28 | |
4c1f658f |
29 | sub OPf_KIDS (); |
a798dbf2 |
30 | use strict; |
31 | @B::SV::ISA = 'B::OBJECT'; |
32 | @B::NULL::ISA = 'B::SV'; |
33 | @B::PV::ISA = 'B::SV'; |
34 | @B::IV::ISA = 'B::SV'; |
4edc9001 |
35 | @B::NV::ISA = 'B::SV'; |
a798dbf2 |
36 | @B::RV::ISA = 'B::SV'; |
37 | @B::PVIV::ISA = qw(B::PV B::IV); |
4edc9001 |
38 | @B::PVNV::ISA = qw(B::PVIV B::NV); |
a798dbf2 |
39 | @B::PVMG::ISA = 'B::PVNV'; |
a01b8a53 |
40 | # Change in the inheritance hierarchy post 5.9.0 |
f5ba1307 |
41 | @B::PVLV::ISA = $] > 5.009 ? 'B::GV' : 'B::PVMG'; |
6822775c |
42 | # BM is eliminated post 5.9.5, but effectively is a specialisation of GV now. |
43 | @B::BM::ISA = $] > 5.009005 ? 'B::GV' : 'B::PVMG'; |
a798dbf2 |
44 | @B::AV::ISA = 'B::PVMG'; |
45 | @B::GV::ISA = 'B::PVMG'; |
46 | @B::HV::ISA = 'B::PVMG'; |
47 | @B::CV::ISA = 'B::PVMG'; |
276493cb |
48 | @B::IO::ISA = 'B::PVMG'; |
49 | @B::FM::ISA = 'B::CV'; |
a798dbf2 |
50 | |
51 | @B::OP::ISA = 'B::OBJECT'; |
52 | @B::UNOP::ISA = 'B::OP'; |
53 | @B::BINOP::ISA = 'B::UNOP'; |
54 | @B::LOGOP::ISA = 'B::UNOP'; |
a798dbf2 |
55 | @B::LISTOP::ISA = 'B::BINOP'; |
56 | @B::SVOP::ISA = 'B::OP'; |
7934575e |
57 | @B::PADOP::ISA = 'B::OP'; |
a798dbf2 |
58 | @B::PVOP::ISA = 'B::OP'; |
a798dbf2 |
59 | @B::LOOP::ISA = 'B::LISTOP'; |
60 | @B::PMOP::ISA = 'B::LISTOP'; |
61 | @B::COP::ISA = 'B::OP'; |
62 | |
63 | @B::SPECIAL::ISA = 'B::OBJECT'; |
64 | |
baccf54f |
65 | @B::optype = qw(OP UNOP BINOP LOGOP LISTOP PMOP SVOP PADOP PVOP LOOP COP); |
66 | # bytecode.pl contained the following comment: |
67 | # Nullsv *must* come first in the following so that the condition |
68 | # ($$sv == 0) can continue to be used to test (sv == Nullsv). |
69 | @B::specialsv_name = qw(Nullsv &PL_sv_undef &PL_sv_yes &PL_sv_no |
70 | (SV*)pWARN_ALL (SV*)pWARN_NONE (SV*)pWARN_STD); |
71 | |
a798dbf2 |
72 | { |
73 | # Stop "-w" from complaining about the lack of a real B::OBJECT class |
74 | package B::OBJECT; |
75 | } |
76 | |
002b978b |
77 | sub B::GV::SAFENAME { |
78 | my $name = (shift())->NAME; |
d9963e60 |
79 | |
80 | # The regex below corresponds to the isCONTROLVAR macro |
81 | # from toke.c |
82 | |
7a9b44b9 |
83 | $name =~ s/^([\cA-\cZ\c\\c[\c]\c?\c_\c^])/"^". |
84 | chr( utf8::unicode_to_native( 64 ^ ord($1) ))/e; |
85 | |
86 | # When we say unicode_to_native we really mean ascii_to_native, |
87 | # which matters iff this is a non-ASCII platform (EBCDIC). |
88 | |
002b978b |
89 | return $name; |
90 | } |
91 | |
d9963e60 |
92 | sub B::IV::int_value { |
93 | my ($self) = @_; |
94 | return (($self->FLAGS() & SVf_IVisUV()) ? $self->UVX : $self->IV); |
95 | } |
96 | |
f3402b25 |
97 | sub B::NULL::as_string() {""} |
98 | sub B::IV::as_string() {goto &B::IV::int_value} |
99 | sub B::PV::as_string() {goto &B::PV::PV} |
100 | |
a798dbf2 |
101 | my $debug; |
102 | my $op_count = 0; |
103 | my @parents = (); |
104 | |
105 | sub debug { |
106 | my ($class, $value) = @_; |
107 | $debug = $value; |
108 | walkoptree_debug($value); |
109 | } |
110 | |
a798dbf2 |
111 | sub class { |
112 | my $obj = shift; |
113 | my $name = ref $obj; |
114 | $name =~ s/^.*:://; |
115 | return $name; |
116 | } |
117 | |
118 | sub parents { \@parents } |
119 | |
120 | # For debugging |
121 | sub peekop { |
122 | my $op = shift; |
3f872cb9 |
123 | return sprintf("%s (0x%x) %s", class($op), $$op, $op->name); |
a798dbf2 |
124 | } |
125 | |
b2590c4e |
126 | sub walkoptree_slow { |
a798dbf2 |
127 | my($op, $method, $level) = @_; |
128 | $op_count++; # just for statistics |
129 | $level ||= 0; |
130 | warn(sprintf("walkoptree: %d. %s\n", $level, peekop($op))) if $debug; |
156f89f0 |
131 | $op->$method($level) if $op->can($method); |
a798dbf2 |
132 | if ($$op && ($op->flags & OPf_KIDS)) { |
133 | my $kid; |
134 | unshift(@parents, $op); |
135 | for ($kid = $op->first; $$kid; $kid = $kid->sibling) { |
b2590c4e |
136 | walkoptree_slow($kid, $method, $level + 1); |
a798dbf2 |
137 | } |
138 | shift @parents; |
139 | } |
156f89f0 |
140 | if (class($op) eq 'PMOP' |
141 | && ref($op->pmreplroot) |
142 | && ${$op->pmreplroot} |
143 | && $op->pmreplroot->isa( 'B::OP' )) |
144 | { |
0091380b |
145 | unshift(@parents, $op); |
146 | walkoptree_slow($op->pmreplroot, $method, $level + 1); |
147 | shift @parents; |
148 | } |
a798dbf2 |
149 | } |
150 | |
151 | sub compile_stats { |
152 | return "Total number of OPs processed: $op_count\n"; |
153 | } |
154 | |
155 | sub timing_info { |
156 | my ($sec, $min, $hr) = localtime; |
157 | my ($user, $sys) = times; |
158 | sprintf("%02d:%02d:%02d user=$user sys=$sys", |
159 | $hr, $min, $sec, $user, $sys); |
160 | } |
161 | |
162 | my %symtable; |
2b8dc4d2 |
163 | |
164 | sub clearsym { |
165 | %symtable = (); |
166 | } |
167 | |
a798dbf2 |
168 | sub savesym { |
169 | my ($obj, $value) = @_; |
170 | # warn(sprintf("savesym: sym_%x => %s\n", $$obj, $value)); # debug |
171 | $symtable{sprintf("sym_%x", $$obj)} = $value; |
172 | } |
173 | |
174 | sub objsym { |
175 | my $obj = shift; |
176 | return $symtable{sprintf("sym_%x", $$obj)}; |
177 | } |
178 | |
179 | sub walkoptree_exec { |
180 | my ($op, $method, $level) = @_; |
244826eb |
181 | $level ||= 0; |
a798dbf2 |
182 | my ($sym, $ppname); |
183 | my $prefix = " " x $level; |
184 | for (; $$op; $op = $op->next) { |
185 | $sym = objsym($op); |
186 | if (defined($sym)) { |
187 | print $prefix, "goto $sym\n"; |
188 | return; |
189 | } |
190 | savesym($op, sprintf("%s (0x%lx)", class($op), $$op)); |
191 | $op->$method($level); |
3f872cb9 |
192 | $ppname = $op->name; |
1a67a97c |
193 | if ($ppname =~ |
62e36f8a |
194 | /^(d?or(assign)?|and(assign)?|mapwhile|grepwhile|entertry|range|cond_expr)$/) |
1a67a97c |
195 | { |
a798dbf2 |
196 | print $prefix, uc($1), " => {\n"; |
197 | walkoptree_exec($op->other, $method, $level + 1); |
198 | print $prefix, "}\n"; |
3f872cb9 |
199 | } elsif ($ppname eq "match" || $ppname eq "subst") { |
a798dbf2 |
200 | my $pmreplstart = $op->pmreplstart; |
201 | if ($$pmreplstart) { |
202 | print $prefix, "PMREPLSTART => {\n"; |
203 | walkoptree_exec($pmreplstart, $method, $level + 1); |
204 | print $prefix, "}\n"; |
205 | } |
3f872cb9 |
206 | } elsif ($ppname eq "substcont") { |
a798dbf2 |
207 | print $prefix, "SUBSTCONT => {\n"; |
208 | walkoptree_exec($op->other->pmreplstart, $method, $level + 1); |
209 | print $prefix, "}\n"; |
210 | $op = $op->other; |
3f872cb9 |
211 | } elsif ($ppname eq "enterloop") { |
a798dbf2 |
212 | print $prefix, "REDO => {\n"; |
213 | walkoptree_exec($op->redoop, $method, $level + 1); |
214 | print $prefix, "}\n", $prefix, "NEXT => {\n"; |
215 | walkoptree_exec($op->nextop, $method, $level + 1); |
216 | print $prefix, "}\n", $prefix, "LAST => {\n"; |
217 | walkoptree_exec($op->lastop, $method, $level + 1); |
218 | print $prefix, "}\n"; |
3f872cb9 |
219 | } elsif ($ppname eq "subst") { |
a798dbf2 |
220 | my $replstart = $op->pmreplstart; |
221 | if ($$replstart) { |
222 | print $prefix, "SUBST => {\n"; |
223 | walkoptree_exec($replstart, $method, $level + 1); |
224 | print $prefix, "}\n"; |
225 | } |
226 | } |
227 | } |
228 | } |
229 | |
230 | sub walksymtable { |
231 | my ($symref, $method, $recurse, $prefix) = @_; |
232 | my $sym; |
0cc1d052 |
233 | my $ref; |
b6b0fb7b |
234 | my $fullname; |
235 | no strict 'refs'; |
0cc1d052 |
236 | $prefix = '' unless defined $prefix; |
237 | while (($sym, $ref) = each %$symref) { |
b6b0fb7b |
238 | $fullname = "*main::".$prefix.$sym; |
a798dbf2 |
239 | if ($sym =~ /::$/) { |
240 | $sym = $prefix . $sym; |
b4e94495 |
241 | if ($sym ne "main::" && $sym ne "<none>::" && &$recurse($sym)) { |
b6b0fb7b |
242 | walksymtable(\%$fullname, $method, $recurse, $sym); |
a798dbf2 |
243 | } |
244 | } else { |
b6b0fb7b |
245 | svref_2object(\*$fullname)->$method(); |
a798dbf2 |
246 | } |
247 | } |
248 | } |
249 | |
250 | { |
251 | package B::Section; |
252 | my $output_fh; |
253 | my %sections; |
85cf7f2e |
254 | |
a798dbf2 |
255 | sub new { |
256 | my ($class, $section, $symtable, $default) = @_; |
257 | $output_fh ||= FileHandle->new_tmpfile; |
258 | my $obj = bless [-1, $section, $symtable, $default], $class; |
259 | $sections{$section} = $obj; |
260 | return $obj; |
261 | } |
85cf7f2e |
262 | |
a798dbf2 |
263 | sub get { |
264 | my ($class, $section) = @_; |
265 | return $sections{$section}; |
266 | } |
267 | |
268 | sub add { |
269 | my $section = shift; |
270 | while (defined($_ = shift)) { |
271 | print $output_fh "$section->[1]\t$_\n"; |
272 | $section->[0]++; |
273 | } |
274 | } |
275 | |
276 | sub index { |
277 | my $section = shift; |
278 | return $section->[0]; |
279 | } |
280 | |
281 | sub name { |
282 | my $section = shift; |
283 | return $section->[1]; |
284 | } |
285 | |
286 | sub symtable { |
287 | my $section = shift; |
288 | return $section->[2]; |
289 | } |
85cf7f2e |
290 | |
a798dbf2 |
291 | sub default { |
292 | my $section = shift; |
293 | return $section->[3]; |
294 | } |
85cf7f2e |
295 | |
a798dbf2 |
296 | sub output { |
297 | my ($section, $fh, $format) = @_; |
298 | my $name = $section->name; |
299 | my $sym = $section->symtable || {}; |
300 | my $default = $section->default; |
301 | |
302 | seek($output_fh, 0, 0); |
303 | while (<$output_fh>) { |
304 | chomp; |
305 | s/^(.*?)\t//; |
306 | if ($1 eq $name) { |
307 | s{(s\\_[0-9a-f]+)} { |
308 | exists($sym->{$1}) ? $sym->{$1} : $default; |
309 | }ge; |
310 | printf $fh $format, $_; |
311 | } |
312 | } |
313 | } |
314 | } |
315 | |
9426adcd |
316 | XSLoader::load 'B'; |
a798dbf2 |
317 | |
318 | 1; |
7f20e9dd |
319 | |
320 | __END__ |
321 | |
322 | =head1 NAME |
323 | |
324 | B - The Perl Compiler |
325 | |
326 | =head1 SYNOPSIS |
327 | |
328 | use B; |
329 | |
330 | =head1 DESCRIPTION |
331 | |
1a52ab62 |
332 | The C<B> module supplies classes which allow a Perl program to delve |
333 | into its own innards. It is the module used to implement the |
334 | "backends" of the Perl compiler. Usage of the compiler does not |
335 | require knowledge of this module: see the F<O> module for the |
336 | user-visible part. The C<B> module is of use to those who want to |
337 | write new compiler backends. This documentation assumes that the |
338 | reader knows a fair amount about perl's internals including such |
339 | things as SVs, OPs and the internal symbol table and syntax tree |
340 | of a program. |
341 | |
85cf7f2e |
342 | =head1 OVERVIEW |
343 | |
344 | The C<B> module contains a set of utility functions for querying the |
345 | current state of the Perl interpreter; typically these functions |
346 | return objects from the B::SV and B::OP classes, or their derived |
347 | classes. These classes in turn define methods for querying the |
348 | resulting objects about their own internal state. |
349 | |
350 | =head1 Utility Functions |
351 | |
352 | The C<B> module exports a variety of functions: some are simple |
353 | utility functions, others provide a Perl program with a way to |
354 | get an initial "handle" on an internal object. |
355 | |
356 | =head2 Functions Returning C<B::SV>, C<B::AV>, C<B::HV>, and C<B::CV> objects |
357 | |
3d036c2b |
358 | For descriptions of the class hierarchy of these objects and the |
85cf7f2e |
359 | methods that can be called on them, see below, L<"OVERVIEW OF |
360 | CLASSES"> and L<"SV-RELATED CLASSES">. |
361 | |
362 | =over 4 |
363 | |
364 | =item sv_undef |
365 | |
366 | Returns the SV object corresponding to the C variable C<sv_undef>. |
367 | |
368 | =item sv_yes |
369 | |
370 | Returns the SV object corresponding to the C variable C<sv_yes>. |
371 | |
372 | =item sv_no |
373 | |
374 | Returns the SV object corresponding to the C variable C<sv_no>. |
375 | |
376 | =item svref_2object(SVREF) |
377 | |
378 | Takes a reference to any Perl value, and turns the referred-to value |
379 | into an object in the appropriate B::OP-derived or B::SV-derived |
380 | class. Apart from functions such as C<main_root>, this is the primary |
381 | way to get an initial "handle" on an internal perl data structure |
382 | which can then be followed with the other access methods. |
383 | |
f31c3107 |
384 | The returned object will only be valid as long as the underlying OPs |
385 | and SVs continue to exist. Do not attempt to use the object after the |
386 | underlying structures are freed. |
387 | |
85cf7f2e |
388 | =item amagic_generation |
389 | |
390 | Returns the SV object corresponding to the C variable C<amagic_generation>. |
391 | |
e13efe3c |
392 | =item init_av |
85cf7f2e |
393 | |
394 | Returns the AV object (i.e. in class B::AV) representing INIT blocks. |
395 | |
ece599bd |
396 | =item check_av |
397 | |
398 | Returns the AV object (i.e. in class B::AV) representing CHECK blocks. |
399 | |
676456c2 |
400 | =item unitcheck_av |
401 | |
402 | Returns the AV object (i.e. in class B::AV) representing UNITCHECK blocks. |
403 | |
85cf7f2e |
404 | =item begin_av |
405 | |
406 | Returns the AV object (i.e. in class B::AV) representing BEGIN blocks. |
407 | |
408 | =item end_av |
409 | |
410 | Returns the AV object (i.e. in class B::AV) representing END blocks. |
411 | |
412 | =item comppadlist |
413 | |
414 | Returns the AV object (i.e. in class B::AV) of the global comppadlist. |
415 | |
416 | =item regex_padav |
417 | |
418 | Only when perl was compiled with ithreads. |
419 | |
e13efe3c |
420 | =item main_cv |
85cf7f2e |
421 | |
422 | Return the (faked) CV corresponding to the main part of the Perl |
423 | program. |
424 | |
425 | =back |
426 | |
427 | =head2 Functions for Examining the Symbol Table |
428 | |
429 | =over 4 |
430 | |
431 | =item walksymtable(SYMREF, METHOD, RECURSE, PREFIX) |
432 | |
433 | Walk the symbol table starting at SYMREF and call METHOD on each |
434 | symbol (a B::GV object) visited. When the walk reaches package |
435 | symbols (such as "Foo::") it invokes RECURSE, passing in the symbol |
436 | name, and only recurses into the package if that sub returns true. |
437 | |
438 | PREFIX is the name of the SYMREF you're walking. |
439 | |
440 | For example: |
441 | |
442 | # Walk CGI's symbol table calling print_subs on each symbol. |
443 | # Recurse only into CGI::Util:: |
444 | walksymtable(\%CGI::, 'print_subs', sub { $_[0] eq 'CGI::Util::' }, |
445 | 'CGI::'); |
446 | |
447 | print_subs() is a B::GV method you have declared. Also see L<"B::GV |
448 | Methods">, below. |
449 | |
450 | =back |
451 | |
452 | =head2 Functions Returning C<B::OP> objects or for walking op trees |
453 | |
3d036c2b |
454 | For descriptions of the class hierarchy of these objects and the |
85cf7f2e |
455 | methods that can be called on them, see below, L<"OVERVIEW OF |
456 | CLASSES"> and L<"OP-RELATED CLASSES">. |
457 | |
458 | =over 4 |
459 | |
460 | =item main_root |
461 | |
462 | Returns the root op (i.e. an object in the appropriate B::OP-derived |
463 | class) of the main part of the Perl program. |
464 | |
465 | =item main_start |
466 | |
467 | Returns the starting op of the main part of the Perl program. |
468 | |
469 | =item walkoptree(OP, METHOD) |
470 | |
471 | Does a tree-walk of the syntax tree based at OP and calls METHOD on |
472 | each op it visits. Each node is visited before its children. If |
473 | C<walkoptree_debug> (see below) has been called to turn debugging on then |
474 | the method C<walkoptree_debug> is called on each op before METHOD is |
475 | called. |
476 | |
477 | =item walkoptree_debug(DEBUG) |
478 | |
479 | Returns the current debugging flag for C<walkoptree>. If the optional |
480 | DEBUG argument is non-zero, it sets the debugging flag to that. See |
481 | the description of C<walkoptree> above for what the debugging flag |
482 | does. |
483 | |
484 | =back |
485 | |
486 | =head2 Miscellaneous Utility Functions |
487 | |
488 | =over 4 |
489 | |
490 | =item ppname(OPNUM) |
491 | |
492 | Return the PP function name (e.g. "pp_add") of op number OPNUM. |
493 | |
494 | =item hash(STR) |
495 | |
496 | Returns a string in the form "0x..." representing the value of the |
497 | internal hash function used by perl on string STR. |
498 | |
499 | =item cast_I32(I) |
500 | |
501 | Casts I to the internal I32 type used by that perl. |
502 | |
503 | =item minus_c |
504 | |
505 | Does the equivalent of the C<-c> command-line option. Obviously, this |
506 | is only useful in a BEGIN block or else the flag is set too late. |
507 | |
508 | =item cstring(STR) |
509 | |
510 | Returns a double-quote-surrounded escaped version of STR which can |
511 | be used as a string in C source code. |
512 | |
513 | =item perlstring(STR) |
514 | |
515 | Returns a double-quote-surrounded escaped version of STR which can |
516 | be used as a string in Perl source code. |
517 | |
518 | =item class(OBJ) |
519 | |
520 | Returns the class of an object without the part of the classname |
521 | preceding the first C<"::">. This is used to turn C<"B::UNOP"> into |
522 | C<"UNOP"> for example. |
523 | |
524 | =item threadsv_names |
525 | |
526 | In a perl compiled for threads, this returns a list of the special |
527 | per-thread threadsv variables. |
528 | |
529 | =back |
530 | |
baccf54f |
531 | =head2 Exported utility variabiles |
532 | |
533 | =over 4 |
534 | |
535 | =item @optype |
536 | |
537 | my $op_type = $optype[$op_type_num]; |
85cf7f2e |
538 | |
baccf54f |
539 | A simple mapping of the op type number to its type (like 'COP' or 'BINOP'). |
540 | |
541 | =item @specialsv_name |
542 | |
543 | my $sv_name = $specialsv_name[$sv_index]; |
544 | |
545 | Certain SV types are considered 'special'. They're represented by |
546 | B::SPECIAL and are referred to by a number from the specialsv_list. |
547 | This array maps that number back to the name of the SV (like 'Nullsv' |
548 | or '&PL_sv_undef'). |
549 | |
550 | =back |
85cf7f2e |
551 | |
552 | |
1a52ab62 |
553 | =head1 OVERVIEW OF CLASSES |
554 | |
555 | The C structures used by Perl's internals to hold SV and OP |
556 | information (PVIV, AV, HV, ..., OP, SVOP, UNOP, ...) are modelled on a |
557 | class hierarchy and the C<B> module gives access to them via a true |
558 | object hierarchy. Structure fields which point to other objects |
559 | (whether types of SV or types of OP) are represented by the C<B> |
85cf7f2e |
560 | module as Perl objects of the appropriate class. |
561 | |
562 | The bulk of the C<B> module is the methods for accessing fields of |
563 | these structures. |
564 | |
565 | Note that all access is read-only. You cannot modify the internals by |
f31c3107 |
566 | using this module. Also, note that the B::OP and B::SV objects created |
567 | by this module are only valid for as long as the underlying objects |
568 | exist; their creation doesn't increase the reference counts of the |
569 | underlying objects. Trying to access the fields of a freed object will |
570 | give incomprehensible results, or worse. |
1a52ab62 |
571 | |
572 | =head2 SV-RELATED CLASSES |
573 | |
6822775c |
574 | B::IV, B::NV, B::RV, B::PV, B::PVIV, B::PVNV, B::PVMG, B::BM (5.9.5 and |
575 | earlier), B::PVLV, B::AV, B::HV, B::CV, B::GV, B::FM, B::IO. These classes |
576 | correspond in the obvious way to the underlying C structures of similar names. |
577 | The inheritance hierarchy mimics the underlying C "inheritance". For 5.9.5 |
a01b8a53 |
578 | and later this is: |
85cf7f2e |
579 | |
6822775c |
580 | B::SV |
581 | | |
582 | +------------+------------+------------+ |
583 | | | | | |
584 | B::PV B::IV B::NV B::RV |
585 | \ / / |
586 | \ / / |
587 | B::PVIV / |
b591c46e |
588 | \ / |
589 | \ / |
590 | \ / |
591 | B::PVNV |
592 | | |
593 | | |
594 | B::PVMG |
595 | | |
6822775c |
596 | +-----+-----+-----+-----+ |
597 | | | | | | |
598 | B::AV B::GV B::HV B::CV B::IO |
599 | | | |
600 | | | |
601 | B::PVLV B::FM |
602 | |
603 | |
604 | For 5.9.0 and earlier, PVLV is a direct subclass of PVMG, and BM is still |
605 | present as a distinct type, so the base of this diagram is |
606 | |
607 | |
608 | | |
609 | | |
610 | B::PVMG |
611 | | |
612 | +------+-----+-----+-----+-----+-----+ |
613 | | | | | | | | |
614 | B::PVLV B::BM B::AV B::GV B::HV B::CV B::IO |
615 | | |
616 | | |
617 | B::FM |
f5ba1307 |
618 | |
619 | |
85cf7f2e |
620 | Access methods correspond to the underlying C macros for field access, |
1a52ab62 |
621 | usually with the leading "class indication" prefix removed (Sv, Av, |
622 | Hv, ...). The leading prefix is only left in cases where its removal |
623 | would cause a clash in method name. For example, C<GvREFCNT> stays |
624 | as-is since its abbreviation would clash with the "superclass" method |
625 | C<REFCNT> (corresponding to the C function C<SvREFCNT>). |
626 | |
85cf7f2e |
627 | =head2 B::SV Methods |
1a52ab62 |
628 | |
629 | =over 4 |
630 | |
631 | =item REFCNT |
632 | |
633 | =item FLAGS |
634 | |
429a5ce7 |
635 | =item object_2svref |
636 | |
637 | Returns a reference to the regular scalar corresponding to this |
638 | B::SV object. In other words, this method is the inverse operation |
639 | to the svref_2object() subroutine. This scalar and other data it points |
640 | at should be considered read-only: modifying them is neither safe nor |
641 | guaranteed to have a sensible effect. |
642 | |
1a52ab62 |
643 | =back |
644 | |
85cf7f2e |
645 | =head2 B::IV Methods |
1a52ab62 |
646 | |
647 | =over 4 |
648 | |
649 | =item IV |
650 | |
d9963e60 |
651 | Returns the value of the IV, I<interpreted as |
652 | a signed integer>. This will be misleading |
653 | if C<FLAGS & SVf_IVisUV>. Perhaps you want the |
654 | C<int_value> method instead? |
655 | |
1a52ab62 |
656 | =item IVX |
657 | |
d9963e60 |
658 | =item UVX |
659 | |
660 | =item int_value |
661 | |
662 | This method returns the value of the IV as an integer. |
663 | It differs from C<IV> in that it returns the correct |
664 | value regardless of whether it's stored signed or |
665 | unsigned. |
666 | |
1a52ab62 |
667 | =item needs64bits |
668 | |
669 | =item packiv |
670 | |
671 | =back |
672 | |
85cf7f2e |
673 | =head2 B::NV Methods |
1a52ab62 |
674 | |
675 | =over 4 |
676 | |
677 | =item NV |
678 | |
679 | =item NVX |
680 | |
681 | =back |
682 | |
85cf7f2e |
683 | =head2 B::RV Methods |
1a52ab62 |
684 | |
685 | =over 4 |
686 | |
687 | =item RV |
688 | |
689 | =back |
690 | |
85cf7f2e |
691 | =head2 B::PV Methods |
1a52ab62 |
692 | |
693 | =over 4 |
694 | |
695 | =item PV |
696 | |
76ef7183 |
697 | This method is the one you usually want. It constructs a |
698 | string using the length and offset information in the struct: |
699 | for ordinary scalars it will return the string that you'd see |
700 | from Perl, even if it contains null characters. |
701 | |
9d2bbe64 |
702 | =item RV |
703 | |
704 | Same as B::RV::RV, except that it will die() if the PV isn't |
705 | a reference. |
706 | |
0b40bd6d |
707 | =item PVX |
708 | |
76ef7183 |
709 | This method is less often useful. It assumes that the string |
710 | stored in the struct is null-terminated, and disregards the |
711 | length information. |
712 | |
713 | It is the appropriate method to use if you need to get the name |
714 | of a lexical variable from a padname array. Lexical variable names |
715 | are always stored with a null terminator, and the length field |
716 | (SvCUR) is overloaded for other purposes and can't be relied on here. |
717 | |
1a52ab62 |
718 | =back |
719 | |
85cf7f2e |
720 | =head2 B::PVMG Methods |
1a52ab62 |
721 | |
722 | =over 4 |
723 | |
724 | =item MAGIC |
725 | |
726 | =item SvSTASH |
727 | |
728 | =back |
729 | |
85cf7f2e |
730 | =head2 B::MAGIC Methods |
1a52ab62 |
731 | |
732 | =over 4 |
733 | |
734 | =item MOREMAGIC |
735 | |
9d2bbe64 |
736 | =item precomp |
737 | |
738 | Only valid on r-magic, returns the string that generated the regexp. |
739 | |
1a52ab62 |
740 | =item PRIVATE |
741 | |
742 | =item TYPE |
743 | |
744 | =item FLAGS |
745 | |
746 | =item OBJ |
747 | |
9d2bbe64 |
748 | Will die() if called on r-magic. |
749 | |
1a52ab62 |
750 | =item PTR |
751 | |
9d2bbe64 |
752 | =item REGEX |
753 | |
754 | Only valid on r-magic, returns the integer value of the REGEX stored |
755 | in the MAGIC. |
756 | |
1a52ab62 |
757 | =back |
758 | |
85cf7f2e |
759 | =head2 B::PVLV Methods |
1a52ab62 |
760 | |
761 | =over 4 |
762 | |
763 | =item TARGOFF |
764 | |
765 | =item TARGLEN |
766 | |
767 | =item TYPE |
768 | |
769 | =item TARG |
770 | |
771 | =back |
772 | |
85cf7f2e |
773 | =head2 B::BM Methods |
1a52ab62 |
774 | |
775 | =over 4 |
776 | |
777 | =item USEFUL |
778 | |
779 | =item PREVIOUS |
780 | |
781 | =item RARE |
782 | |
783 | =item TABLE |
784 | |
785 | =back |
786 | |
85cf7f2e |
787 | =head2 B::GV Methods |
1a52ab62 |
788 | |
789 | =over 4 |
790 | |
87d7fd28 |
791 | =item is_empty |
792 | |
793 | This method returns TRUE if the GP field of the GV is NULL. |
794 | |
1a52ab62 |
795 | =item NAME |
796 | |
002b978b |
797 | =item SAFENAME |
798 | |
799 | This method returns the name of the glob, but if the first |
800 | character of the name is a control character, then it converts |
801 | it to ^X first, so that *^G would return "^G" rather than "\cG". |
802 | |
803 | It's useful if you want to print out the name of a variable. |
804 | If you restrict yourself to globs which exist at compile-time |
805 | then the result ought to be unambiguous, because code like |
806 | C<${"^G"} = 1> is compiled as two ops - a constant string and |
807 | a dereference (rv2gv) - so that the glob is created at runtime. |
808 | |
809 | If you're working with globs at runtime, and need to disambiguate |
810 | *^G from *{"^G"}, then you should use the raw NAME method. |
811 | |
1a52ab62 |
812 | =item STASH |
813 | |
814 | =item SV |
815 | |
816 | =item IO |
817 | |
818 | =item FORM |
819 | |
820 | =item AV |
821 | |
822 | =item HV |
823 | |
824 | =item EGV |
825 | |
826 | =item CV |
827 | |
828 | =item CVGEN |
829 | |
830 | =item LINE |
831 | |
b195d487 |
832 | =item FILE |
833 | |
1a52ab62 |
834 | =item FILEGV |
835 | |
836 | =item GvREFCNT |
837 | |
838 | =item FLAGS |
839 | |
840 | =back |
841 | |
85cf7f2e |
842 | =head2 B::IO Methods |
1a52ab62 |
843 | |
844 | =over 4 |
845 | |
846 | =item LINES |
847 | |
848 | =item PAGE |
849 | |
850 | =item PAGE_LEN |
851 | |
852 | =item LINES_LEFT |
853 | |
854 | =item TOP_NAME |
855 | |
856 | =item TOP_GV |
857 | |
858 | =item FMT_NAME |
859 | |
860 | =item FMT_GV |
861 | |
862 | =item BOTTOM_NAME |
863 | |
864 | =item BOTTOM_GV |
865 | |
866 | =item SUBPROCESS |
867 | |
868 | =item IoTYPE |
869 | |
870 | =item IoFLAGS |
871 | |
9d2bbe64 |
872 | =item IsSTD |
873 | |
874 | Takes one arguments ( 'stdin' | 'stdout' | 'stderr' ) and returns true |
875 | if the IoIFP of the object is equal to the handle whose name was |
876 | passed as argument ( i.e. $io->IsSTD('stderr') is true if |
877 | IoIFP($io) == PerlIO_stdin() ). |
878 | |
1a52ab62 |
879 | =back |
880 | |
85cf7f2e |
881 | =head2 B::AV Methods |
1a52ab62 |
882 | |
883 | =over 4 |
884 | |
885 | =item FILL |
886 | |
887 | =item MAX |
888 | |
1a52ab62 |
889 | =item ARRAY |
890 | |
429a5ce7 |
891 | =item ARRAYelt |
892 | |
893 | Like C<ARRAY>, but takes an index as an argument to get only one element, |
894 | rather than a list of all of them. |
895 | |
edcc7c74 |
896 | =item OFF |
897 | |
898 | This method is deprecated if running under Perl 5.8, and is no longer present |
899 | if running under Perl 5.9 |
900 | |
901 | =item AvFLAGS |
902 | |
903 | This method returns the AV specific flags. In Perl 5.9 these are now stored |
904 | in with the main SV flags, so this method is no longer present. |
905 | |
1a52ab62 |
906 | =back |
907 | |
85cf7f2e |
908 | =head2 B::CV Methods |
1a52ab62 |
909 | |
910 | =over 4 |
911 | |
912 | =item STASH |
913 | |
914 | =item START |
915 | |
916 | =item ROOT |
917 | |
918 | =item GV |
919 | |
57843af0 |
920 | =item FILE |
921 | |
1a52ab62 |
922 | =item DEPTH |
923 | |
924 | =item PADLIST |
925 | |
926 | =item OUTSIDE |
927 | |
a3985cdc |
928 | =item OUTSIDE_SEQ |
929 | |
1a52ab62 |
930 | =item XSUB |
931 | |
932 | =item XSUBANY |
933 | |
9d2bbe64 |
934 | For constant subroutines, returns the constant SV returned by the subroutine. |
935 | |
5cfd8ad4 |
936 | =item CvFLAGS |
937 | |
de3f1649 |
938 | =item const_sv |
939 | |
1a52ab62 |
940 | =back |
941 | |
85cf7f2e |
942 | =head2 B::HV Methods |
1a52ab62 |
943 | |
944 | =over 4 |
945 | |
946 | =item FILL |
947 | |
948 | =item MAX |
949 | |
950 | =item KEYS |
951 | |
952 | =item RITER |
953 | |
954 | =item NAME |
955 | |
1a52ab62 |
956 | =item ARRAY |
957 | |
edcc7c74 |
958 | =item PMROOT |
959 | |
960 | This method is not present if running under Perl 5.9, as the PMROOT |
961 | information is no longer stored directly in the hash. |
962 | |
1a52ab62 |
963 | =back |
964 | |
965 | =head2 OP-RELATED CLASSES |
966 | |
85cf7f2e |
967 | C<B::OP>, C<B::UNOP>, C<B::BINOP>, C<B::LOGOP>, C<B::LISTOP>, C<B::PMOP>, |
651aa52e |
968 | C<B::SVOP>, C<B::PADOP>, C<B::PVOP>, C<B::LOOP>, C<B::COP>. |
85cf7f2e |
969 | |
970 | These classes correspond in the obvious way to the underlying C |
971 | structures of similar names. The inheritance hierarchy mimics the |
972 | underlying C "inheritance": |
973 | |
974 | B::OP |
975 | | |
5ce57cc0 |
976 | +---------------+--------+--------+-------+ |
977 | | | | | | |
978 | B::UNOP B::SVOP B::PADOP B::COP B::PVOP |
85cf7f2e |
979 | ,' `-. |
980 | / `--. |
981 | B::BINOP B::LOGOP |
982 | | |
983 | | |
984 | B::LISTOP |
985 | ,' `. |
986 | / \ |
987 | B::LOOP B::PMOP |
988 | |
989 | Access methods correspond to the underlying C structre field names, |
990 | with the leading "class indication" prefix (C<"op_">) removed. |
991 | |
992 | =head2 B::OP Methods |
1a52ab62 |
993 | |
a60ba18b |
994 | These methods get the values of similarly named fields within the OP |
995 | data structure. See top of C<op.h> for more info. |
996 | |
1a52ab62 |
997 | =over 4 |
998 | |
999 | =item next |
1000 | |
1001 | =item sibling |
1002 | |
3f872cb9 |
1003 | =item name |
1004 | |
1005 | This returns the op name as a string (e.g. "add", "rv2av"). |
1006 | |
1a52ab62 |
1007 | =item ppaddr |
1008 | |
dc333d64 |
1009 | This returns the function name as a string (e.g. "PL_ppaddr[OP_ADD]", |
1010 | "PL_ppaddr[OP_RV2AV]"). |
1a52ab62 |
1011 | |
1012 | =item desc |
1013 | |
4369b173 |
1014 | This returns the op description from the global C PL_op_desc array |
1a52ab62 |
1015 | (e.g. "addition" "array deref"). |
1016 | |
1017 | =item targ |
1018 | |
1019 | =item type |
1020 | |
a60ba18b |
1021 | =item opt |
1022 | |
1a52ab62 |
1023 | =item flags |
1024 | |
1025 | =item private |
1026 | |
a60ba18b |
1027 | =item spare |
1028 | |
1a52ab62 |
1029 | =back |
1030 | |
1031 | =head2 B::UNOP METHOD |
1032 | |
1033 | =over 4 |
1034 | |
1035 | =item first |
1036 | |
1037 | =back |
1038 | |
1039 | =head2 B::BINOP METHOD |
1040 | |
1041 | =over 4 |
1042 | |
1043 | =item last |
1044 | |
1045 | =back |
1046 | |
1047 | =head2 B::LOGOP METHOD |
1048 | |
1049 | =over 4 |
1050 | |
1051 | =item other |
1052 | |
1053 | =back |
1054 | |
1a52ab62 |
1055 | =head2 B::LISTOP METHOD |
1056 | |
1057 | =over 4 |
1058 | |
1059 | =item children |
1060 | |
1061 | =back |
1062 | |
85cf7f2e |
1063 | =head2 B::PMOP Methods |
1a52ab62 |
1064 | |
1065 | =over 4 |
1066 | |
1067 | =item pmreplroot |
1068 | |
1069 | =item pmreplstart |
1070 | |
1071 | =item pmnext |
1072 | |
1073 | =item pmregexp |
1074 | |
1075 | =item pmflags |
1076 | |
c737faaf |
1077 | =item extflags |
1a52ab62 |
1078 | |
1079 | =item precomp |
1080 | |
651aa52e |
1081 | =item pmoffset |
9d2bbe64 |
1082 | |
1083 | Only when perl was compiled with ithreads. |
1084 | |
1a52ab62 |
1085 | =back |
1086 | |
1087 | =head2 B::SVOP METHOD |
1088 | |
1089 | =over 4 |
1090 | |
1091 | =item sv |
1092 | |
065a1863 |
1093 | =item gv |
1094 | |
1a52ab62 |
1095 | =back |
1096 | |
7934575e |
1097 | =head2 B::PADOP METHOD |
1a52ab62 |
1098 | |
1099 | =over 4 |
1100 | |
7934575e |
1101 | =item padix |
1a52ab62 |
1102 | |
1103 | =back |
1104 | |
1105 | =head2 B::PVOP METHOD |
1106 | |
1107 | =over 4 |
1108 | |
1109 | =item pv |
1110 | |
1111 | =back |
1112 | |
85cf7f2e |
1113 | =head2 B::LOOP Methods |
1a52ab62 |
1114 | |
1115 | =over 4 |
1116 | |
1117 | =item redoop |
1118 | |
1119 | =item nextop |
1120 | |
1121 | =item lastop |
1122 | |
1123 | =back |
1124 | |
85cf7f2e |
1125 | =head2 B::COP Methods |
1a52ab62 |
1126 | |
1127 | =over 4 |
1128 | |
1129 | =item label |
1130 | |
1131 | =item stash |
1132 | |
6e6a1aef |
1133 | =item stashpv |
1134 | |
57843af0 |
1135 | =item file |
1a52ab62 |
1136 | |
1137 | =item cop_seq |
1138 | |
1139 | =item arybase |
1140 | |
1141 | =item line |
1142 | |
6e6a1aef |
1143 | =item warnings |
1144 | |
1145 | =item io |
1146 | |
d5ec2987 |
1147 | =item hints |
1148 | |
1a52ab62 |
1149 | =back |
1150 | |
7f20e9dd |
1151 | |
1152 | =head1 AUTHOR |
1153 | |
1154 | Malcolm Beattie, C<mbeattie@sable.ox.ac.uk> |
1155 | |
1156 | =cut |