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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 | |
4df7f6af |
10 | our $VERSION = '1.18'; |
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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'; |
4df7f6af |
36 | # RV is eliminated with 5.11.0, but effectively is a specialisation of IV now. |
37 | @B::RV::ISA = $] > 5.011 ? 'B::IV' : 'B::SV'; |
a798dbf2 |
38 | @B::PVIV::ISA = qw(B::PV B::IV); |
4edc9001 |
39 | @B::PVNV::ISA = qw(B::PVIV B::NV); |
a798dbf2 |
40 | @B::PVMG::ISA = 'B::PVNV'; |
a01b8a53 |
41 | # Change in the inheritance hierarchy post 5.9.0 |
f5ba1307 |
42 | @B::PVLV::ISA = $] > 5.009 ? 'B::GV' : 'B::PVMG'; |
6822775c |
43 | # BM is eliminated post 5.9.5, but effectively is a specialisation of GV now. |
44 | @B::BM::ISA = $] > 5.009005 ? 'B::GV' : 'B::PVMG'; |
a798dbf2 |
45 | @B::AV::ISA = 'B::PVMG'; |
46 | @B::GV::ISA = 'B::PVMG'; |
47 | @B::HV::ISA = 'B::PVMG'; |
48 | @B::CV::ISA = 'B::PVMG'; |
276493cb |
49 | @B::IO::ISA = 'B::PVMG'; |
50 | @B::FM::ISA = 'B::CV'; |
a798dbf2 |
51 | |
52 | @B::OP::ISA = 'B::OBJECT'; |
53 | @B::UNOP::ISA = 'B::OP'; |
54 | @B::BINOP::ISA = 'B::UNOP'; |
55 | @B::LOGOP::ISA = 'B::UNOP'; |
a798dbf2 |
56 | @B::LISTOP::ISA = 'B::BINOP'; |
57 | @B::SVOP::ISA = 'B::OP'; |
7934575e |
58 | @B::PADOP::ISA = 'B::OP'; |
a798dbf2 |
59 | @B::PVOP::ISA = 'B::OP'; |
a798dbf2 |
60 | @B::LOOP::ISA = 'B::LISTOP'; |
61 | @B::PMOP::ISA = 'B::LISTOP'; |
62 | @B::COP::ISA = 'B::OP'; |
63 | |
64 | @B::SPECIAL::ISA = 'B::OBJECT'; |
65 | |
baccf54f |
66 | @B::optype = qw(OP UNOP BINOP LOGOP LISTOP PMOP SVOP PADOP PVOP LOOP COP); |
67 | # bytecode.pl contained the following comment: |
68 | # Nullsv *must* come first in the following so that the condition |
69 | # ($$sv == 0) can continue to be used to test (sv == Nullsv). |
70 | @B::specialsv_name = qw(Nullsv &PL_sv_undef &PL_sv_yes &PL_sv_no |
71 | (SV*)pWARN_ALL (SV*)pWARN_NONE (SV*)pWARN_STD); |
72 | |
a798dbf2 |
73 | { |
74 | # Stop "-w" from complaining about the lack of a real B::OBJECT class |
75 | package B::OBJECT; |
76 | } |
77 | |
002b978b |
78 | sub B::GV::SAFENAME { |
79 | my $name = (shift())->NAME; |
d9963e60 |
80 | |
81 | # The regex below corresponds to the isCONTROLVAR macro |
82 | # from toke.c |
83 | |
7a9b44b9 |
84 | $name =~ s/^([\cA-\cZ\c\\c[\c]\c?\c_\c^])/"^". |
85 | chr( utf8::unicode_to_native( 64 ^ ord($1) ))/e; |
86 | |
87 | # When we say unicode_to_native we really mean ascii_to_native, |
88 | # which matters iff this is a non-ASCII platform (EBCDIC). |
89 | |
002b978b |
90 | return $name; |
91 | } |
92 | |
d9963e60 |
93 | sub B::IV::int_value { |
94 | my ($self) = @_; |
95 | return (($self->FLAGS() & SVf_IVisUV()) ? $self->UVX : $self->IV); |
96 | } |
97 | |
f3402b25 |
98 | sub B::NULL::as_string() {""} |
99 | sub B::IV::as_string() {goto &B::IV::int_value} |
100 | sub B::PV::as_string() {goto &B::PV::PV} |
101 | |
a798dbf2 |
102 | my $debug; |
103 | my $op_count = 0; |
104 | my @parents = (); |
105 | |
106 | sub debug { |
107 | my ($class, $value) = @_; |
108 | $debug = $value; |
109 | walkoptree_debug($value); |
110 | } |
111 | |
a798dbf2 |
112 | sub class { |
113 | my $obj = shift; |
114 | my $name = ref $obj; |
115 | $name =~ s/^.*:://; |
116 | return $name; |
117 | } |
118 | |
119 | sub parents { \@parents } |
120 | |
121 | # For debugging |
122 | sub peekop { |
123 | my $op = shift; |
3f872cb9 |
124 | return sprintf("%s (0x%x) %s", class($op), $$op, $op->name); |
a798dbf2 |
125 | } |
126 | |
b2590c4e |
127 | sub walkoptree_slow { |
a798dbf2 |
128 | my($op, $method, $level) = @_; |
129 | $op_count++; # just for statistics |
130 | $level ||= 0; |
131 | warn(sprintf("walkoptree: %d. %s\n", $level, peekop($op))) if $debug; |
156f89f0 |
132 | $op->$method($level) if $op->can($method); |
a798dbf2 |
133 | if ($$op && ($op->flags & OPf_KIDS)) { |
134 | my $kid; |
135 | unshift(@parents, $op); |
136 | for ($kid = $op->first; $$kid; $kid = $kid->sibling) { |
b2590c4e |
137 | walkoptree_slow($kid, $method, $level + 1); |
a798dbf2 |
138 | } |
139 | shift @parents; |
140 | } |
156f89f0 |
141 | if (class($op) eq 'PMOP' |
142 | && ref($op->pmreplroot) |
143 | && ${$op->pmreplroot} |
144 | && $op->pmreplroot->isa( 'B::OP' )) |
145 | { |
0091380b |
146 | unshift(@parents, $op); |
147 | walkoptree_slow($op->pmreplroot, $method, $level + 1); |
148 | shift @parents; |
149 | } |
a798dbf2 |
150 | } |
151 | |
152 | sub compile_stats { |
153 | return "Total number of OPs processed: $op_count\n"; |
154 | } |
155 | |
156 | sub timing_info { |
157 | my ($sec, $min, $hr) = localtime; |
158 | my ($user, $sys) = times; |
159 | sprintf("%02d:%02d:%02d user=$user sys=$sys", |
160 | $hr, $min, $sec, $user, $sys); |
161 | } |
162 | |
163 | my %symtable; |
2b8dc4d2 |
164 | |
165 | sub clearsym { |
166 | %symtable = (); |
167 | } |
168 | |
a798dbf2 |
169 | sub savesym { |
170 | my ($obj, $value) = @_; |
171 | # warn(sprintf("savesym: sym_%x => %s\n", $$obj, $value)); # debug |
172 | $symtable{sprintf("sym_%x", $$obj)} = $value; |
173 | } |
174 | |
175 | sub objsym { |
176 | my $obj = shift; |
177 | return $symtable{sprintf("sym_%x", $$obj)}; |
178 | } |
179 | |
180 | sub walkoptree_exec { |
181 | my ($op, $method, $level) = @_; |
244826eb |
182 | $level ||= 0; |
a798dbf2 |
183 | my ($sym, $ppname); |
184 | my $prefix = " " x $level; |
185 | for (; $$op; $op = $op->next) { |
186 | $sym = objsym($op); |
187 | if (defined($sym)) { |
188 | print $prefix, "goto $sym\n"; |
189 | return; |
190 | } |
191 | savesym($op, sprintf("%s (0x%lx)", class($op), $$op)); |
192 | $op->$method($level); |
3f872cb9 |
193 | $ppname = $op->name; |
1a67a97c |
194 | if ($ppname =~ |
62e36f8a |
195 | /^(d?or(assign)?|and(assign)?|mapwhile|grepwhile|entertry|range|cond_expr)$/) |
1a67a97c |
196 | { |
a798dbf2 |
197 | print $prefix, uc($1), " => {\n"; |
198 | walkoptree_exec($op->other, $method, $level + 1); |
199 | print $prefix, "}\n"; |
3f872cb9 |
200 | } elsif ($ppname eq "match" || $ppname eq "subst") { |
a798dbf2 |
201 | my $pmreplstart = $op->pmreplstart; |
202 | if ($$pmreplstart) { |
203 | print $prefix, "PMREPLSTART => {\n"; |
204 | walkoptree_exec($pmreplstart, $method, $level + 1); |
205 | print $prefix, "}\n"; |
206 | } |
3f872cb9 |
207 | } elsif ($ppname eq "substcont") { |
a798dbf2 |
208 | print $prefix, "SUBSTCONT => {\n"; |
209 | walkoptree_exec($op->other->pmreplstart, $method, $level + 1); |
210 | print $prefix, "}\n"; |
211 | $op = $op->other; |
3f872cb9 |
212 | } elsif ($ppname eq "enterloop") { |
a798dbf2 |
213 | print $prefix, "REDO => {\n"; |
214 | walkoptree_exec($op->redoop, $method, $level + 1); |
215 | print $prefix, "}\n", $prefix, "NEXT => {\n"; |
216 | walkoptree_exec($op->nextop, $method, $level + 1); |
217 | print $prefix, "}\n", $prefix, "LAST => {\n"; |
218 | walkoptree_exec($op->lastop, $method, $level + 1); |
219 | print $prefix, "}\n"; |
3f872cb9 |
220 | } elsif ($ppname eq "subst") { |
a798dbf2 |
221 | my $replstart = $op->pmreplstart; |
222 | if ($$replstart) { |
223 | print $prefix, "SUBST => {\n"; |
224 | walkoptree_exec($replstart, $method, $level + 1); |
225 | print $prefix, "}\n"; |
226 | } |
227 | } |
228 | } |
229 | } |
230 | |
231 | sub walksymtable { |
232 | my ($symref, $method, $recurse, $prefix) = @_; |
233 | my $sym; |
0cc1d052 |
234 | my $ref; |
b6b0fb7b |
235 | my $fullname; |
236 | no strict 'refs'; |
0cc1d052 |
237 | $prefix = '' unless defined $prefix; |
238 | while (($sym, $ref) = each %$symref) { |
b6b0fb7b |
239 | $fullname = "*main::".$prefix.$sym; |
a798dbf2 |
240 | if ($sym =~ /::$/) { |
241 | $sym = $prefix . $sym; |
b4e94495 |
242 | if ($sym ne "main::" && $sym ne "<none>::" && &$recurse($sym)) { |
b6b0fb7b |
243 | walksymtable(\%$fullname, $method, $recurse, $sym); |
a798dbf2 |
244 | } |
245 | } else { |
b6b0fb7b |
246 | svref_2object(\*$fullname)->$method(); |
a798dbf2 |
247 | } |
248 | } |
249 | } |
250 | |
251 | { |
252 | package B::Section; |
253 | my $output_fh; |
254 | my %sections; |
85cf7f2e |
255 | |
a798dbf2 |
256 | sub new { |
257 | my ($class, $section, $symtable, $default) = @_; |
258 | $output_fh ||= FileHandle->new_tmpfile; |
259 | my $obj = bless [-1, $section, $symtable, $default], $class; |
260 | $sections{$section} = $obj; |
261 | return $obj; |
262 | } |
85cf7f2e |
263 | |
a798dbf2 |
264 | sub get { |
265 | my ($class, $section) = @_; |
266 | return $sections{$section}; |
267 | } |
268 | |
269 | sub add { |
270 | my $section = shift; |
271 | while (defined($_ = shift)) { |
272 | print $output_fh "$section->[1]\t$_\n"; |
273 | $section->[0]++; |
274 | } |
275 | } |
276 | |
277 | sub index { |
278 | my $section = shift; |
279 | return $section->[0]; |
280 | } |
281 | |
282 | sub name { |
283 | my $section = shift; |
284 | return $section->[1]; |
285 | } |
286 | |
287 | sub symtable { |
288 | my $section = shift; |
289 | return $section->[2]; |
290 | } |
85cf7f2e |
291 | |
a798dbf2 |
292 | sub default { |
293 | my $section = shift; |
294 | return $section->[3]; |
295 | } |
85cf7f2e |
296 | |
a798dbf2 |
297 | sub output { |
298 | my ($section, $fh, $format) = @_; |
299 | my $name = $section->name; |
300 | my $sym = $section->symtable || {}; |
301 | my $default = $section->default; |
302 | |
303 | seek($output_fh, 0, 0); |
304 | while (<$output_fh>) { |
305 | chomp; |
306 | s/^(.*?)\t//; |
307 | if ($1 eq $name) { |
308 | s{(s\\_[0-9a-f]+)} { |
309 | exists($sym->{$1}) ? $sym->{$1} : $default; |
310 | }ge; |
311 | printf $fh $format, $_; |
312 | } |
313 | } |
314 | } |
315 | } |
316 | |
9426adcd |
317 | XSLoader::load 'B'; |
a798dbf2 |
318 | |
319 | 1; |
7f20e9dd |
320 | |
321 | __END__ |
322 | |
323 | =head1 NAME |
324 | |
325 | B - The Perl Compiler |
326 | |
327 | =head1 SYNOPSIS |
328 | |
329 | use B; |
330 | |
331 | =head1 DESCRIPTION |
332 | |
1a52ab62 |
333 | The C<B> module supplies classes which allow a Perl program to delve |
334 | into its own innards. It is the module used to implement the |
335 | "backends" of the Perl compiler. Usage of the compiler does not |
336 | require knowledge of this module: see the F<O> module for the |
337 | user-visible part. The C<B> module is of use to those who want to |
338 | write new compiler backends. This documentation assumes that the |
339 | reader knows a fair amount about perl's internals including such |
340 | things as SVs, OPs and the internal symbol table and syntax tree |
341 | of a program. |
342 | |
85cf7f2e |
343 | =head1 OVERVIEW |
344 | |
345 | The C<B> module contains a set of utility functions for querying the |
346 | current state of the Perl interpreter; typically these functions |
347 | return objects from the B::SV and B::OP classes, or their derived |
348 | classes. These classes in turn define methods for querying the |
349 | resulting objects about their own internal state. |
350 | |
351 | =head1 Utility Functions |
352 | |
353 | The C<B> module exports a variety of functions: some are simple |
354 | utility functions, others provide a Perl program with a way to |
355 | get an initial "handle" on an internal object. |
356 | |
357 | =head2 Functions Returning C<B::SV>, C<B::AV>, C<B::HV>, and C<B::CV> objects |
358 | |
3d036c2b |
359 | For descriptions of the class hierarchy of these objects and the |
85cf7f2e |
360 | methods that can be called on them, see below, L<"OVERVIEW OF |
361 | CLASSES"> and L<"SV-RELATED CLASSES">. |
362 | |
363 | =over 4 |
364 | |
365 | =item sv_undef |
366 | |
367 | Returns the SV object corresponding to the C variable C<sv_undef>. |
368 | |
369 | =item sv_yes |
370 | |
371 | Returns the SV object corresponding to the C variable C<sv_yes>. |
372 | |
373 | =item sv_no |
374 | |
375 | Returns the SV object corresponding to the C variable C<sv_no>. |
376 | |
377 | =item svref_2object(SVREF) |
378 | |
379 | Takes a reference to any Perl value, and turns the referred-to value |
380 | into an object in the appropriate B::OP-derived or B::SV-derived |
381 | class. Apart from functions such as C<main_root>, this is the primary |
382 | way to get an initial "handle" on an internal perl data structure |
383 | which can then be followed with the other access methods. |
384 | |
f31c3107 |
385 | The returned object will only be valid as long as the underlying OPs |
386 | and SVs continue to exist. Do not attempt to use the object after the |
387 | underlying structures are freed. |
388 | |
85cf7f2e |
389 | =item amagic_generation |
390 | |
391 | Returns the SV object corresponding to the C variable C<amagic_generation>. |
392 | |
e13efe3c |
393 | =item init_av |
85cf7f2e |
394 | |
395 | Returns the AV object (i.e. in class B::AV) representing INIT blocks. |
396 | |
ece599bd |
397 | =item check_av |
398 | |
399 | Returns the AV object (i.e. in class B::AV) representing CHECK blocks. |
400 | |
676456c2 |
401 | =item unitcheck_av |
402 | |
403 | Returns the AV object (i.e. in class B::AV) representing UNITCHECK blocks. |
404 | |
85cf7f2e |
405 | =item begin_av |
406 | |
407 | Returns the AV object (i.e. in class B::AV) representing BEGIN blocks. |
408 | |
409 | =item end_av |
410 | |
411 | Returns the AV object (i.e. in class B::AV) representing END blocks. |
412 | |
413 | =item comppadlist |
414 | |
415 | Returns the AV object (i.e. in class B::AV) of the global comppadlist. |
416 | |
417 | =item regex_padav |
418 | |
419 | Only when perl was compiled with ithreads. |
420 | |
e13efe3c |
421 | =item main_cv |
85cf7f2e |
422 | |
423 | Return the (faked) CV corresponding to the main part of the Perl |
424 | program. |
425 | |
426 | =back |
427 | |
428 | =head2 Functions for Examining the Symbol Table |
429 | |
430 | =over 4 |
431 | |
432 | =item walksymtable(SYMREF, METHOD, RECURSE, PREFIX) |
433 | |
434 | Walk the symbol table starting at SYMREF and call METHOD on each |
435 | symbol (a B::GV object) visited. When the walk reaches package |
436 | symbols (such as "Foo::") it invokes RECURSE, passing in the symbol |
437 | name, and only recurses into the package if that sub returns true. |
438 | |
439 | PREFIX is the name of the SYMREF you're walking. |
440 | |
441 | For example: |
442 | |
443 | # Walk CGI's symbol table calling print_subs on each symbol. |
444 | # Recurse only into CGI::Util:: |
445 | walksymtable(\%CGI::, 'print_subs', sub { $_[0] eq 'CGI::Util::' }, |
446 | 'CGI::'); |
447 | |
448 | print_subs() is a B::GV method you have declared. Also see L<"B::GV |
449 | Methods">, below. |
450 | |
451 | =back |
452 | |
453 | =head2 Functions Returning C<B::OP> objects or for walking op trees |
454 | |
3d036c2b |
455 | For descriptions of the class hierarchy of these objects and the |
85cf7f2e |
456 | methods that can be called on them, see below, L<"OVERVIEW OF |
457 | CLASSES"> and L<"OP-RELATED CLASSES">. |
458 | |
459 | =over 4 |
460 | |
461 | =item main_root |
462 | |
463 | Returns the root op (i.e. an object in the appropriate B::OP-derived |
464 | class) of the main part of the Perl program. |
465 | |
466 | =item main_start |
467 | |
468 | Returns the starting op of the main part of the Perl program. |
469 | |
470 | =item walkoptree(OP, METHOD) |
471 | |
472 | Does a tree-walk of the syntax tree based at OP and calls METHOD on |
473 | each op it visits. Each node is visited before its children. If |
474 | C<walkoptree_debug> (see below) has been called to turn debugging on then |
475 | the method C<walkoptree_debug> is called on each op before METHOD is |
476 | called. |
477 | |
478 | =item walkoptree_debug(DEBUG) |
479 | |
480 | Returns the current debugging flag for C<walkoptree>. If the optional |
481 | DEBUG argument is non-zero, it sets the debugging flag to that. See |
482 | the description of C<walkoptree> above for what the debugging flag |
483 | does. |
484 | |
485 | =back |
486 | |
487 | =head2 Miscellaneous Utility Functions |
488 | |
489 | =over 4 |
490 | |
491 | =item ppname(OPNUM) |
492 | |
493 | Return the PP function name (e.g. "pp_add") of op number OPNUM. |
494 | |
495 | =item hash(STR) |
496 | |
497 | Returns a string in the form "0x..." representing the value of the |
498 | internal hash function used by perl on string STR. |
499 | |
500 | =item cast_I32(I) |
501 | |
502 | Casts I to the internal I32 type used by that perl. |
503 | |
504 | =item minus_c |
505 | |
506 | Does the equivalent of the C<-c> command-line option. Obviously, this |
507 | is only useful in a BEGIN block or else the flag is set too late. |
508 | |
509 | =item cstring(STR) |
510 | |
511 | Returns a double-quote-surrounded escaped version of STR which can |
512 | be used as a string in C source code. |
513 | |
514 | =item perlstring(STR) |
515 | |
516 | Returns a double-quote-surrounded escaped version of STR which can |
517 | be used as a string in Perl source code. |
518 | |
519 | =item class(OBJ) |
520 | |
521 | Returns the class of an object without the part of the classname |
522 | preceding the first C<"::">. This is used to turn C<"B::UNOP"> into |
523 | C<"UNOP"> for example. |
524 | |
525 | =item threadsv_names |
526 | |
527 | In a perl compiled for threads, this returns a list of the special |
528 | per-thread threadsv variables. |
529 | |
530 | =back |
531 | |
baccf54f |
532 | =head2 Exported utility variabiles |
533 | |
534 | =over 4 |
535 | |
536 | =item @optype |
537 | |
538 | my $op_type = $optype[$op_type_num]; |
85cf7f2e |
539 | |
baccf54f |
540 | A simple mapping of the op type number to its type (like 'COP' or 'BINOP'). |
541 | |
542 | =item @specialsv_name |
543 | |
544 | my $sv_name = $specialsv_name[$sv_index]; |
545 | |
546 | Certain SV types are considered 'special'. They're represented by |
547 | B::SPECIAL and are referred to by a number from the specialsv_list. |
548 | This array maps that number back to the name of the SV (like 'Nullsv' |
549 | or '&PL_sv_undef'). |
550 | |
551 | =back |
85cf7f2e |
552 | |
553 | |
1a52ab62 |
554 | =head1 OVERVIEW OF CLASSES |
555 | |
556 | The C structures used by Perl's internals to hold SV and OP |
557 | information (PVIV, AV, HV, ..., OP, SVOP, UNOP, ...) are modelled on a |
558 | class hierarchy and the C<B> module gives access to them via a true |
559 | object hierarchy. Structure fields which point to other objects |
560 | (whether types of SV or types of OP) are represented by the C<B> |
85cf7f2e |
561 | module as Perl objects of the appropriate class. |
562 | |
563 | The bulk of the C<B> module is the methods for accessing fields of |
564 | these structures. |
565 | |
566 | Note that all access is read-only. You cannot modify the internals by |
f31c3107 |
567 | using this module. Also, note that the B::OP and B::SV objects created |
568 | by this module are only valid for as long as the underlying objects |
569 | exist; their creation doesn't increase the reference counts of the |
570 | underlying objects. Trying to access the fields of a freed object will |
571 | give incomprehensible results, or worse. |
1a52ab62 |
572 | |
573 | =head2 SV-RELATED CLASSES |
574 | |
6822775c |
575 | B::IV, B::NV, B::RV, B::PV, B::PVIV, B::PVNV, B::PVMG, B::BM (5.9.5 and |
576 | earlier), B::PVLV, B::AV, B::HV, B::CV, B::GV, B::FM, B::IO. These classes |
577 | correspond in the obvious way to the underlying C structures of similar names. |
4df7f6af |
578 | The inheritance hierarchy mimics the underlying C "inheritance". For the |
579 | 5.10, 5.10.1 I<etc> this is: |
85cf7f2e |
580 | |
6822775c |
581 | B::SV |
582 | | |
583 | +------------+------------+------------+ |
584 | | | | | |
585 | B::PV B::IV B::NV B::RV |
586 | \ / / |
587 | \ / / |
588 | B::PVIV / |
b591c46e |
589 | \ / |
590 | \ / |
591 | \ / |
592 | B::PVNV |
593 | | |
594 | | |
595 | B::PVMG |
596 | | |
6822775c |
597 | +-----+-----+-----+-----+ |
598 | | | | | | |
599 | B::AV B::GV B::HV B::CV B::IO |
600 | | | |
601 | | | |
602 | B::PVLV B::FM |
603 | |
604 | |
4df7f6af |
605 | For 5.11.0 and later, B::RV is abolished, and IVs can be used to store |
606 | references. |
607 | |
6822775c |
608 | For 5.9.0 and earlier, PVLV is a direct subclass of PVMG, and BM is still |
609 | present as a distinct type, so the base of this diagram is |
610 | |
611 | |
612 | | |
613 | | |
614 | B::PVMG |
615 | | |
616 | +------+-----+-----+-----+-----+-----+ |
617 | | | | | | | | |
618 | B::PVLV B::BM B::AV B::GV B::HV B::CV B::IO |
619 | | |
620 | | |
621 | B::FM |
f5ba1307 |
622 | |
623 | |
85cf7f2e |
624 | Access methods correspond to the underlying C macros for field access, |
1a52ab62 |
625 | usually with the leading "class indication" prefix removed (Sv, Av, |
626 | Hv, ...). The leading prefix is only left in cases where its removal |
627 | would cause a clash in method name. For example, C<GvREFCNT> stays |
628 | as-is since its abbreviation would clash with the "superclass" method |
629 | C<REFCNT> (corresponding to the C function C<SvREFCNT>). |
630 | |
85cf7f2e |
631 | =head2 B::SV Methods |
1a52ab62 |
632 | |
633 | =over 4 |
634 | |
635 | =item REFCNT |
636 | |
637 | =item FLAGS |
638 | |
429a5ce7 |
639 | =item object_2svref |
640 | |
641 | Returns a reference to the regular scalar corresponding to this |
642 | B::SV object. In other words, this method is the inverse operation |
643 | to the svref_2object() subroutine. This scalar and other data it points |
644 | at should be considered read-only: modifying them is neither safe nor |
645 | guaranteed to have a sensible effect. |
646 | |
1a52ab62 |
647 | =back |
648 | |
85cf7f2e |
649 | =head2 B::IV Methods |
1a52ab62 |
650 | |
651 | =over 4 |
652 | |
653 | =item IV |
654 | |
d9963e60 |
655 | Returns the value of the IV, I<interpreted as |
656 | a signed integer>. This will be misleading |
657 | if C<FLAGS & SVf_IVisUV>. Perhaps you want the |
658 | C<int_value> method instead? |
659 | |
1a52ab62 |
660 | =item IVX |
661 | |
d9963e60 |
662 | =item UVX |
663 | |
664 | =item int_value |
665 | |
666 | This method returns the value of the IV as an integer. |
667 | It differs from C<IV> in that it returns the correct |
668 | value regardless of whether it's stored signed or |
669 | unsigned. |
670 | |
1a52ab62 |
671 | =item needs64bits |
672 | |
673 | =item packiv |
674 | |
675 | =back |
676 | |
85cf7f2e |
677 | =head2 B::NV Methods |
1a52ab62 |
678 | |
679 | =over 4 |
680 | |
681 | =item NV |
682 | |
683 | =item NVX |
684 | |
685 | =back |
686 | |
85cf7f2e |
687 | =head2 B::RV Methods |
1a52ab62 |
688 | |
689 | =over 4 |
690 | |
691 | =item RV |
692 | |
693 | =back |
694 | |
85cf7f2e |
695 | =head2 B::PV Methods |
1a52ab62 |
696 | |
697 | =over 4 |
698 | |
699 | =item PV |
700 | |
76ef7183 |
701 | This method is the one you usually want. It constructs a |
702 | string using the length and offset information in the struct: |
703 | for ordinary scalars it will return the string that you'd see |
704 | from Perl, even if it contains null characters. |
705 | |
9d2bbe64 |
706 | =item RV |
707 | |
708 | Same as B::RV::RV, except that it will die() if the PV isn't |
709 | a reference. |
710 | |
0b40bd6d |
711 | =item PVX |
712 | |
76ef7183 |
713 | This method is less often useful. It assumes that the string |
714 | stored in the struct is null-terminated, and disregards the |
715 | length information. |
716 | |
717 | It is the appropriate method to use if you need to get the name |
718 | of a lexical variable from a padname array. Lexical variable names |
719 | are always stored with a null terminator, and the length field |
720 | (SvCUR) is overloaded for other purposes and can't be relied on here. |
721 | |
1a52ab62 |
722 | =back |
723 | |
85cf7f2e |
724 | =head2 B::PVMG Methods |
1a52ab62 |
725 | |
726 | =over 4 |
727 | |
728 | =item MAGIC |
729 | |
730 | =item SvSTASH |
731 | |
732 | =back |
733 | |
85cf7f2e |
734 | =head2 B::MAGIC Methods |
1a52ab62 |
735 | |
736 | =over 4 |
737 | |
738 | =item MOREMAGIC |
739 | |
9d2bbe64 |
740 | =item precomp |
741 | |
742 | Only valid on r-magic, returns the string that generated the regexp. |
743 | |
1a52ab62 |
744 | =item PRIVATE |
745 | |
746 | =item TYPE |
747 | |
748 | =item FLAGS |
749 | |
750 | =item OBJ |
751 | |
9d2bbe64 |
752 | Will die() if called on r-magic. |
753 | |
1a52ab62 |
754 | =item PTR |
755 | |
9d2bbe64 |
756 | =item REGEX |
757 | |
758 | Only valid on r-magic, returns the integer value of the REGEX stored |
759 | in the MAGIC. |
760 | |
1a52ab62 |
761 | =back |
762 | |
85cf7f2e |
763 | =head2 B::PVLV Methods |
1a52ab62 |
764 | |
765 | =over 4 |
766 | |
767 | =item TARGOFF |
768 | |
769 | =item TARGLEN |
770 | |
771 | =item TYPE |
772 | |
773 | =item TARG |
774 | |
775 | =back |
776 | |
85cf7f2e |
777 | =head2 B::BM Methods |
1a52ab62 |
778 | |
779 | =over 4 |
780 | |
781 | =item USEFUL |
782 | |
783 | =item PREVIOUS |
784 | |
785 | =item RARE |
786 | |
787 | =item TABLE |
788 | |
789 | =back |
790 | |
85cf7f2e |
791 | =head2 B::GV Methods |
1a52ab62 |
792 | |
793 | =over 4 |
794 | |
87d7fd28 |
795 | =item is_empty |
796 | |
797 | This method returns TRUE if the GP field of the GV is NULL. |
798 | |
1a52ab62 |
799 | =item NAME |
800 | |
002b978b |
801 | =item SAFENAME |
802 | |
803 | This method returns the name of the glob, but if the first |
804 | character of the name is a control character, then it converts |
805 | it to ^X first, so that *^G would return "^G" rather than "\cG". |
806 | |
807 | It's useful if you want to print out the name of a variable. |
808 | If you restrict yourself to globs which exist at compile-time |
809 | then the result ought to be unambiguous, because code like |
810 | C<${"^G"} = 1> is compiled as two ops - a constant string and |
811 | a dereference (rv2gv) - so that the glob is created at runtime. |
812 | |
813 | If you're working with globs at runtime, and need to disambiguate |
814 | *^G from *{"^G"}, then you should use the raw NAME method. |
815 | |
1a52ab62 |
816 | =item STASH |
817 | |
818 | =item SV |
819 | |
820 | =item IO |
821 | |
822 | =item FORM |
823 | |
824 | =item AV |
825 | |
826 | =item HV |
827 | |
828 | =item EGV |
829 | |
830 | =item CV |
831 | |
832 | =item CVGEN |
833 | |
834 | =item LINE |
835 | |
b195d487 |
836 | =item FILE |
837 | |
1a52ab62 |
838 | =item FILEGV |
839 | |
840 | =item GvREFCNT |
841 | |
842 | =item FLAGS |
843 | |
844 | =back |
845 | |
85cf7f2e |
846 | =head2 B::IO Methods |
1a52ab62 |
847 | |
848 | =over 4 |
849 | |
850 | =item LINES |
851 | |
852 | =item PAGE |
853 | |
854 | =item PAGE_LEN |
855 | |
856 | =item LINES_LEFT |
857 | |
858 | =item TOP_NAME |
859 | |
860 | =item TOP_GV |
861 | |
862 | =item FMT_NAME |
863 | |
864 | =item FMT_GV |
865 | |
866 | =item BOTTOM_NAME |
867 | |
868 | =item BOTTOM_GV |
869 | |
870 | =item SUBPROCESS |
871 | |
872 | =item IoTYPE |
873 | |
874 | =item IoFLAGS |
875 | |
9d2bbe64 |
876 | =item IsSTD |
877 | |
878 | Takes one arguments ( 'stdin' | 'stdout' | 'stderr' ) and returns true |
879 | if the IoIFP of the object is equal to the handle whose name was |
880 | passed as argument ( i.e. $io->IsSTD('stderr') is true if |
881 | IoIFP($io) == PerlIO_stdin() ). |
882 | |
1a52ab62 |
883 | =back |
884 | |
85cf7f2e |
885 | =head2 B::AV Methods |
1a52ab62 |
886 | |
887 | =over 4 |
888 | |
889 | =item FILL |
890 | |
891 | =item MAX |
892 | |
1a52ab62 |
893 | =item ARRAY |
894 | |
429a5ce7 |
895 | =item ARRAYelt |
896 | |
897 | Like C<ARRAY>, but takes an index as an argument to get only one element, |
898 | rather than a list of all of them. |
899 | |
edcc7c74 |
900 | =item OFF |
901 | |
902 | This method is deprecated if running under Perl 5.8, and is no longer present |
903 | if running under Perl 5.9 |
904 | |
905 | =item AvFLAGS |
906 | |
907 | This method returns the AV specific flags. In Perl 5.9 these are now stored |
908 | in with the main SV flags, so this method is no longer present. |
909 | |
1a52ab62 |
910 | =back |
911 | |
85cf7f2e |
912 | =head2 B::CV Methods |
1a52ab62 |
913 | |
914 | =over 4 |
915 | |
916 | =item STASH |
917 | |
918 | =item START |
919 | |
920 | =item ROOT |
921 | |
922 | =item GV |
923 | |
57843af0 |
924 | =item FILE |
925 | |
1a52ab62 |
926 | =item DEPTH |
927 | |
928 | =item PADLIST |
929 | |
930 | =item OUTSIDE |
931 | |
a3985cdc |
932 | =item OUTSIDE_SEQ |
933 | |
1a52ab62 |
934 | =item XSUB |
935 | |
936 | =item XSUBANY |
937 | |
9d2bbe64 |
938 | For constant subroutines, returns the constant SV returned by the subroutine. |
939 | |
5cfd8ad4 |
940 | =item CvFLAGS |
941 | |
de3f1649 |
942 | =item const_sv |
943 | |
1a52ab62 |
944 | =back |
945 | |
85cf7f2e |
946 | =head2 B::HV Methods |
1a52ab62 |
947 | |
948 | =over 4 |
949 | |
950 | =item FILL |
951 | |
952 | =item MAX |
953 | |
954 | =item KEYS |
955 | |
956 | =item RITER |
957 | |
958 | =item NAME |
959 | |
1a52ab62 |
960 | =item ARRAY |
961 | |
edcc7c74 |
962 | =item PMROOT |
963 | |
964 | This method is not present if running under Perl 5.9, as the PMROOT |
965 | information is no longer stored directly in the hash. |
966 | |
1a52ab62 |
967 | =back |
968 | |
969 | =head2 OP-RELATED CLASSES |
970 | |
85cf7f2e |
971 | C<B::OP>, C<B::UNOP>, C<B::BINOP>, C<B::LOGOP>, C<B::LISTOP>, C<B::PMOP>, |
651aa52e |
972 | C<B::SVOP>, C<B::PADOP>, C<B::PVOP>, C<B::LOOP>, C<B::COP>. |
85cf7f2e |
973 | |
974 | These classes correspond in the obvious way to the underlying C |
975 | structures of similar names. The inheritance hierarchy mimics the |
976 | underlying C "inheritance": |
977 | |
978 | B::OP |
979 | | |
5ce57cc0 |
980 | +---------------+--------+--------+-------+ |
981 | | | | | | |
982 | B::UNOP B::SVOP B::PADOP B::COP B::PVOP |
85cf7f2e |
983 | ,' `-. |
984 | / `--. |
985 | B::BINOP B::LOGOP |
986 | | |
987 | | |
988 | B::LISTOP |
989 | ,' `. |
990 | / \ |
991 | B::LOOP B::PMOP |
992 | |
993 | Access methods correspond to the underlying C structre field names, |
994 | with the leading "class indication" prefix (C<"op_">) removed. |
995 | |
996 | =head2 B::OP Methods |
1a52ab62 |
997 | |
a60ba18b |
998 | These methods get the values of similarly named fields within the OP |
999 | data structure. See top of C<op.h> for more info. |
1000 | |
1a52ab62 |
1001 | =over 4 |
1002 | |
1003 | =item next |
1004 | |
1005 | =item sibling |
1006 | |
3f872cb9 |
1007 | =item name |
1008 | |
1009 | This returns the op name as a string (e.g. "add", "rv2av"). |
1010 | |
1a52ab62 |
1011 | =item ppaddr |
1012 | |
dc333d64 |
1013 | This returns the function name as a string (e.g. "PL_ppaddr[OP_ADD]", |
1014 | "PL_ppaddr[OP_RV2AV]"). |
1a52ab62 |
1015 | |
1016 | =item desc |
1017 | |
4369b173 |
1018 | This returns the op description from the global C PL_op_desc array |
1a52ab62 |
1019 | (e.g. "addition" "array deref"). |
1020 | |
1021 | =item targ |
1022 | |
1023 | =item type |
1024 | |
a60ba18b |
1025 | =item opt |
1026 | |
1a52ab62 |
1027 | =item flags |
1028 | |
1029 | =item private |
1030 | |
a60ba18b |
1031 | =item spare |
1032 | |
1a52ab62 |
1033 | =back |
1034 | |
1035 | =head2 B::UNOP METHOD |
1036 | |
1037 | =over 4 |
1038 | |
1039 | =item first |
1040 | |
1041 | =back |
1042 | |
1043 | =head2 B::BINOP METHOD |
1044 | |
1045 | =over 4 |
1046 | |
1047 | =item last |
1048 | |
1049 | =back |
1050 | |
1051 | =head2 B::LOGOP METHOD |
1052 | |
1053 | =over 4 |
1054 | |
1055 | =item other |
1056 | |
1057 | =back |
1058 | |
1a52ab62 |
1059 | =head2 B::LISTOP METHOD |
1060 | |
1061 | =over 4 |
1062 | |
1063 | =item children |
1064 | |
1065 | =back |
1066 | |
85cf7f2e |
1067 | =head2 B::PMOP Methods |
1a52ab62 |
1068 | |
1069 | =over 4 |
1070 | |
1071 | =item pmreplroot |
1072 | |
1073 | =item pmreplstart |
1074 | |
1075 | =item pmnext |
1076 | |
1077 | =item pmregexp |
1078 | |
1079 | =item pmflags |
1080 | |
c737faaf |
1081 | =item extflags |
1a52ab62 |
1082 | |
1083 | =item precomp |
1084 | |
651aa52e |
1085 | =item pmoffset |
9d2bbe64 |
1086 | |
1087 | Only when perl was compiled with ithreads. |
1088 | |
1a52ab62 |
1089 | =back |
1090 | |
1091 | =head2 B::SVOP METHOD |
1092 | |
1093 | =over 4 |
1094 | |
1095 | =item sv |
1096 | |
065a1863 |
1097 | =item gv |
1098 | |
1a52ab62 |
1099 | =back |
1100 | |
7934575e |
1101 | =head2 B::PADOP METHOD |
1a52ab62 |
1102 | |
1103 | =over 4 |
1104 | |
7934575e |
1105 | =item padix |
1a52ab62 |
1106 | |
1107 | =back |
1108 | |
1109 | =head2 B::PVOP METHOD |
1110 | |
1111 | =over 4 |
1112 | |
1113 | =item pv |
1114 | |
1115 | =back |
1116 | |
85cf7f2e |
1117 | =head2 B::LOOP Methods |
1a52ab62 |
1118 | |
1119 | =over 4 |
1120 | |
1121 | =item redoop |
1122 | |
1123 | =item nextop |
1124 | |
1125 | =item lastop |
1126 | |
1127 | =back |
1128 | |
85cf7f2e |
1129 | =head2 B::COP Methods |
1a52ab62 |
1130 | |
1131 | =over 4 |
1132 | |
1133 | =item label |
1134 | |
1135 | =item stash |
1136 | |
6e6a1aef |
1137 | =item stashpv |
1138 | |
57843af0 |
1139 | =item file |
1a52ab62 |
1140 | |
1141 | =item cop_seq |
1142 | |
1143 | =item arybase |
1144 | |
1145 | =item line |
1146 | |
6e6a1aef |
1147 | =item warnings |
1148 | |
1149 | =item io |
1150 | |
d5ec2987 |
1151 | =item hints |
1152 | |
b47e7f93 |
1153 | =item hints_hash |
1154 | |
1a52ab62 |
1155 | =back |
1156 | |
7f20e9dd |
1157 | |
1158 | =head1 AUTHOR |
1159 | |
1160 | Malcolm Beattie, C<mbeattie@sable.ox.ac.uk> |
1161 | |
1162 | =cut |