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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 | |
85594c31 |
10 | our $VERSION = '1.16'; |
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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'; |
a798dbf2 |
42 | @B::BM::ISA = 'B::PVMG'; |
43 | @B::AV::ISA = 'B::PVMG'; |
44 | @B::GV::ISA = 'B::PVMG'; |
45 | @B::HV::ISA = 'B::PVMG'; |
46 | @B::CV::ISA = 'B::PVMG'; |
276493cb |
47 | @B::IO::ISA = 'B::PVMG'; |
48 | @B::FM::ISA = 'B::CV'; |
a798dbf2 |
49 | |
50 | @B::OP::ISA = 'B::OBJECT'; |
51 | @B::UNOP::ISA = 'B::OP'; |
52 | @B::BINOP::ISA = 'B::UNOP'; |
53 | @B::LOGOP::ISA = 'B::UNOP'; |
a798dbf2 |
54 | @B::LISTOP::ISA = 'B::BINOP'; |
55 | @B::SVOP::ISA = 'B::OP'; |
7934575e |
56 | @B::PADOP::ISA = 'B::OP'; |
a798dbf2 |
57 | @B::PVOP::ISA = 'B::OP'; |
a798dbf2 |
58 | @B::LOOP::ISA = 'B::LISTOP'; |
59 | @B::PMOP::ISA = 'B::LISTOP'; |
60 | @B::COP::ISA = 'B::OP'; |
61 | |
62 | @B::SPECIAL::ISA = 'B::OBJECT'; |
63 | |
baccf54f |
64 | @B::optype = qw(OP UNOP BINOP LOGOP LISTOP PMOP SVOP PADOP PVOP LOOP COP); |
65 | # bytecode.pl contained the following comment: |
66 | # Nullsv *must* come first in the following so that the condition |
67 | # ($$sv == 0) can continue to be used to test (sv == Nullsv). |
68 | @B::specialsv_name = qw(Nullsv &PL_sv_undef &PL_sv_yes &PL_sv_no |
69 | (SV*)pWARN_ALL (SV*)pWARN_NONE (SV*)pWARN_STD); |
70 | |
a798dbf2 |
71 | { |
72 | # Stop "-w" from complaining about the lack of a real B::OBJECT class |
73 | package B::OBJECT; |
74 | } |
75 | |
002b978b |
76 | sub B::GV::SAFENAME { |
77 | my $name = (shift())->NAME; |
d9963e60 |
78 | |
79 | # The regex below corresponds to the isCONTROLVAR macro |
80 | # from toke.c |
81 | |
7a9b44b9 |
82 | $name =~ s/^([\cA-\cZ\c\\c[\c]\c?\c_\c^])/"^". |
83 | chr( utf8::unicode_to_native( 64 ^ ord($1) ))/e; |
84 | |
85 | # When we say unicode_to_native we really mean ascii_to_native, |
86 | # which matters iff this is a non-ASCII platform (EBCDIC). |
87 | |
002b978b |
88 | return $name; |
89 | } |
90 | |
d9963e60 |
91 | sub B::IV::int_value { |
92 | my ($self) = @_; |
93 | return (($self->FLAGS() & SVf_IVisUV()) ? $self->UVX : $self->IV); |
94 | } |
95 | |
f3402b25 |
96 | sub B::NULL::as_string() {""} |
97 | sub B::IV::as_string() {goto &B::IV::int_value} |
98 | sub B::PV::as_string() {goto &B::PV::PV} |
99 | |
a798dbf2 |
100 | my $debug; |
101 | my $op_count = 0; |
102 | my @parents = (); |
103 | |
104 | sub debug { |
105 | my ($class, $value) = @_; |
106 | $debug = $value; |
107 | walkoptree_debug($value); |
108 | } |
109 | |
a798dbf2 |
110 | sub class { |
111 | my $obj = shift; |
112 | my $name = ref $obj; |
113 | $name =~ s/^.*:://; |
114 | return $name; |
115 | } |
116 | |
117 | sub parents { \@parents } |
118 | |
119 | # For debugging |
120 | sub peekop { |
121 | my $op = shift; |
3f872cb9 |
122 | return sprintf("%s (0x%x) %s", class($op), $$op, $op->name); |
a798dbf2 |
123 | } |
124 | |
b2590c4e |
125 | sub walkoptree_slow { |
a798dbf2 |
126 | my($op, $method, $level) = @_; |
127 | $op_count++; # just for statistics |
128 | $level ||= 0; |
129 | warn(sprintf("walkoptree: %d. %s\n", $level, peekop($op))) if $debug; |
156f89f0 |
130 | $op->$method($level) if $op->can($method); |
a798dbf2 |
131 | if ($$op && ($op->flags & OPf_KIDS)) { |
132 | my $kid; |
133 | unshift(@parents, $op); |
134 | for ($kid = $op->first; $$kid; $kid = $kid->sibling) { |
b2590c4e |
135 | walkoptree_slow($kid, $method, $level + 1); |
a798dbf2 |
136 | } |
137 | shift @parents; |
138 | } |
156f89f0 |
139 | if (class($op) eq 'PMOP' |
140 | && ref($op->pmreplroot) |
141 | && ${$op->pmreplroot} |
142 | && $op->pmreplroot->isa( 'B::OP' )) |
143 | { |
0091380b |
144 | unshift(@parents, $op); |
145 | walkoptree_slow($op->pmreplroot, $method, $level + 1); |
146 | shift @parents; |
147 | } |
a798dbf2 |
148 | } |
149 | |
150 | sub compile_stats { |
151 | return "Total number of OPs processed: $op_count\n"; |
152 | } |
153 | |
154 | sub timing_info { |
155 | my ($sec, $min, $hr) = localtime; |
156 | my ($user, $sys) = times; |
157 | sprintf("%02d:%02d:%02d user=$user sys=$sys", |
158 | $hr, $min, $sec, $user, $sys); |
159 | } |
160 | |
161 | my %symtable; |
2b8dc4d2 |
162 | |
163 | sub clearsym { |
164 | %symtable = (); |
165 | } |
166 | |
a798dbf2 |
167 | sub savesym { |
168 | my ($obj, $value) = @_; |
169 | # warn(sprintf("savesym: sym_%x => %s\n", $$obj, $value)); # debug |
170 | $symtable{sprintf("sym_%x", $$obj)} = $value; |
171 | } |
172 | |
173 | sub objsym { |
174 | my $obj = shift; |
175 | return $symtable{sprintf("sym_%x", $$obj)}; |
176 | } |
177 | |
178 | sub walkoptree_exec { |
179 | my ($op, $method, $level) = @_; |
244826eb |
180 | $level ||= 0; |
a798dbf2 |
181 | my ($sym, $ppname); |
182 | my $prefix = " " x $level; |
183 | for (; $$op; $op = $op->next) { |
184 | $sym = objsym($op); |
185 | if (defined($sym)) { |
186 | print $prefix, "goto $sym\n"; |
187 | return; |
188 | } |
189 | savesym($op, sprintf("%s (0x%lx)", class($op), $$op)); |
190 | $op->$method($level); |
3f872cb9 |
191 | $ppname = $op->name; |
1a67a97c |
192 | if ($ppname =~ |
62e36f8a |
193 | /^(d?or(assign)?|and(assign)?|mapwhile|grepwhile|entertry|range|cond_expr)$/) |
1a67a97c |
194 | { |
a798dbf2 |
195 | print $prefix, uc($1), " => {\n"; |
196 | walkoptree_exec($op->other, $method, $level + 1); |
197 | print $prefix, "}\n"; |
3f872cb9 |
198 | } elsif ($ppname eq "match" || $ppname eq "subst") { |
a798dbf2 |
199 | my $pmreplstart = $op->pmreplstart; |
200 | if ($$pmreplstart) { |
201 | print $prefix, "PMREPLSTART => {\n"; |
202 | walkoptree_exec($pmreplstart, $method, $level + 1); |
203 | print $prefix, "}\n"; |
204 | } |
3f872cb9 |
205 | } elsif ($ppname eq "substcont") { |
a798dbf2 |
206 | print $prefix, "SUBSTCONT => {\n"; |
207 | walkoptree_exec($op->other->pmreplstart, $method, $level + 1); |
208 | print $prefix, "}\n"; |
209 | $op = $op->other; |
3f872cb9 |
210 | } elsif ($ppname eq "enterloop") { |
a798dbf2 |
211 | print $prefix, "REDO => {\n"; |
212 | walkoptree_exec($op->redoop, $method, $level + 1); |
213 | print $prefix, "}\n", $prefix, "NEXT => {\n"; |
214 | walkoptree_exec($op->nextop, $method, $level + 1); |
215 | print $prefix, "}\n", $prefix, "LAST => {\n"; |
216 | walkoptree_exec($op->lastop, $method, $level + 1); |
217 | print $prefix, "}\n"; |
3f872cb9 |
218 | } elsif ($ppname eq "subst") { |
a798dbf2 |
219 | my $replstart = $op->pmreplstart; |
220 | if ($$replstart) { |
221 | print $prefix, "SUBST => {\n"; |
222 | walkoptree_exec($replstart, $method, $level + 1); |
223 | print $prefix, "}\n"; |
224 | } |
225 | } |
226 | } |
227 | } |
228 | |
229 | sub walksymtable { |
230 | my ($symref, $method, $recurse, $prefix) = @_; |
231 | my $sym; |
0cc1d052 |
232 | my $ref; |
b6b0fb7b |
233 | my $fullname; |
234 | no strict 'refs'; |
0cc1d052 |
235 | $prefix = '' unless defined $prefix; |
236 | while (($sym, $ref) = each %$symref) { |
b6b0fb7b |
237 | $fullname = "*main::".$prefix.$sym; |
a798dbf2 |
238 | if ($sym =~ /::$/) { |
239 | $sym = $prefix . $sym; |
b4e94495 |
240 | if ($sym ne "main::" && $sym ne "<none>::" && &$recurse($sym)) { |
b6b0fb7b |
241 | walksymtable(\%$fullname, $method, $recurse, $sym); |
a798dbf2 |
242 | } |
243 | } else { |
b6b0fb7b |
244 | svref_2object(\*$fullname)->$method(); |
a798dbf2 |
245 | } |
246 | } |
247 | } |
248 | |
249 | { |
250 | package B::Section; |
251 | my $output_fh; |
252 | my %sections; |
85cf7f2e |
253 | |
a798dbf2 |
254 | sub new { |
255 | my ($class, $section, $symtable, $default) = @_; |
256 | $output_fh ||= FileHandle->new_tmpfile; |
257 | my $obj = bless [-1, $section, $symtable, $default], $class; |
258 | $sections{$section} = $obj; |
259 | return $obj; |
260 | } |
85cf7f2e |
261 | |
a798dbf2 |
262 | sub get { |
263 | my ($class, $section) = @_; |
264 | return $sections{$section}; |
265 | } |
266 | |
267 | sub add { |
268 | my $section = shift; |
269 | while (defined($_ = shift)) { |
270 | print $output_fh "$section->[1]\t$_\n"; |
271 | $section->[0]++; |
272 | } |
273 | } |
274 | |
275 | sub index { |
276 | my $section = shift; |
277 | return $section->[0]; |
278 | } |
279 | |
280 | sub name { |
281 | my $section = shift; |
282 | return $section->[1]; |
283 | } |
284 | |
285 | sub symtable { |
286 | my $section = shift; |
287 | return $section->[2]; |
288 | } |
85cf7f2e |
289 | |
a798dbf2 |
290 | sub default { |
291 | my $section = shift; |
292 | return $section->[3]; |
293 | } |
85cf7f2e |
294 | |
a798dbf2 |
295 | sub output { |
296 | my ($section, $fh, $format) = @_; |
297 | my $name = $section->name; |
298 | my $sym = $section->symtable || {}; |
299 | my $default = $section->default; |
300 | |
301 | seek($output_fh, 0, 0); |
302 | while (<$output_fh>) { |
303 | chomp; |
304 | s/^(.*?)\t//; |
305 | if ($1 eq $name) { |
306 | s{(s\\_[0-9a-f]+)} { |
307 | exists($sym->{$1}) ? $sym->{$1} : $default; |
308 | }ge; |
309 | printf $fh $format, $_; |
310 | } |
311 | } |
312 | } |
313 | } |
314 | |
9426adcd |
315 | XSLoader::load 'B'; |
a798dbf2 |
316 | |
317 | 1; |
7f20e9dd |
318 | |
319 | __END__ |
320 | |
321 | =head1 NAME |
322 | |
323 | B - The Perl Compiler |
324 | |
325 | =head1 SYNOPSIS |
326 | |
327 | use B; |
328 | |
329 | =head1 DESCRIPTION |
330 | |
1a52ab62 |
331 | The C<B> module supplies classes which allow a Perl program to delve |
332 | into its own innards. It is the module used to implement the |
333 | "backends" of the Perl compiler. Usage of the compiler does not |
334 | require knowledge of this module: see the F<O> module for the |
335 | user-visible part. The C<B> module is of use to those who want to |
336 | write new compiler backends. This documentation assumes that the |
337 | reader knows a fair amount about perl's internals including such |
338 | things as SVs, OPs and the internal symbol table and syntax tree |
339 | of a program. |
340 | |
85cf7f2e |
341 | =head1 OVERVIEW |
342 | |
343 | The C<B> module contains a set of utility functions for querying the |
344 | current state of the Perl interpreter; typically these functions |
345 | return objects from the B::SV and B::OP classes, or their derived |
346 | classes. These classes in turn define methods for querying the |
347 | resulting objects about their own internal state. |
348 | |
349 | =head1 Utility Functions |
350 | |
351 | The C<B> module exports a variety of functions: some are simple |
352 | utility functions, others provide a Perl program with a way to |
353 | get an initial "handle" on an internal object. |
354 | |
355 | =head2 Functions Returning C<B::SV>, C<B::AV>, C<B::HV>, and C<B::CV> objects |
356 | |
3d036c2b |
357 | For descriptions of the class hierarchy of these objects and the |
85cf7f2e |
358 | methods that can be called on them, see below, L<"OVERVIEW OF |
359 | CLASSES"> and L<"SV-RELATED CLASSES">. |
360 | |
361 | =over 4 |
362 | |
363 | =item sv_undef |
364 | |
365 | Returns the SV object corresponding to the C variable C<sv_undef>. |
366 | |
367 | =item sv_yes |
368 | |
369 | Returns the SV object corresponding to the C variable C<sv_yes>. |
370 | |
371 | =item sv_no |
372 | |
373 | Returns the SV object corresponding to the C variable C<sv_no>. |
374 | |
375 | =item svref_2object(SVREF) |
376 | |
377 | Takes a reference to any Perl value, and turns the referred-to value |
378 | into an object in the appropriate B::OP-derived or B::SV-derived |
379 | class. Apart from functions such as C<main_root>, this is the primary |
380 | way to get an initial "handle" on an internal perl data structure |
381 | which can then be followed with the other access methods. |
382 | |
f31c3107 |
383 | The returned object will only be valid as long as the underlying OPs |
384 | and SVs continue to exist. Do not attempt to use the object after the |
385 | underlying structures are freed. |
386 | |
85cf7f2e |
387 | =item amagic_generation |
388 | |
389 | Returns the SV object corresponding to the C variable C<amagic_generation>. |
390 | |
e13efe3c |
391 | =item init_av |
85cf7f2e |
392 | |
393 | Returns the AV object (i.e. in class B::AV) representing INIT blocks. |
394 | |
ece599bd |
395 | =item check_av |
396 | |
397 | Returns the AV object (i.e. in class B::AV) representing CHECK blocks. |
398 | |
676456c2 |
399 | =item unitcheck_av |
400 | |
401 | Returns the AV object (i.e. in class B::AV) representing UNITCHECK blocks. |
402 | |
85cf7f2e |
403 | =item begin_av |
404 | |
405 | Returns the AV object (i.e. in class B::AV) representing BEGIN blocks. |
406 | |
407 | =item end_av |
408 | |
409 | Returns the AV object (i.e. in class B::AV) representing END blocks. |
410 | |
411 | =item comppadlist |
412 | |
413 | Returns the AV object (i.e. in class B::AV) of the global comppadlist. |
414 | |
415 | =item regex_padav |
416 | |
417 | Only when perl was compiled with ithreads. |
418 | |
e13efe3c |
419 | =item main_cv |
85cf7f2e |
420 | |
421 | Return the (faked) CV corresponding to the main part of the Perl |
422 | program. |
423 | |
424 | =back |
425 | |
426 | =head2 Functions for Examining the Symbol Table |
427 | |
428 | =over 4 |
429 | |
430 | =item walksymtable(SYMREF, METHOD, RECURSE, PREFIX) |
431 | |
432 | Walk the symbol table starting at SYMREF and call METHOD on each |
433 | symbol (a B::GV object) visited. When the walk reaches package |
434 | symbols (such as "Foo::") it invokes RECURSE, passing in the symbol |
435 | name, and only recurses into the package if that sub returns true. |
436 | |
437 | PREFIX is the name of the SYMREF you're walking. |
438 | |
439 | For example: |
440 | |
441 | # Walk CGI's symbol table calling print_subs on each symbol. |
442 | # Recurse only into CGI::Util:: |
443 | walksymtable(\%CGI::, 'print_subs', sub { $_[0] eq 'CGI::Util::' }, |
444 | 'CGI::'); |
445 | |
446 | print_subs() is a B::GV method you have declared. Also see L<"B::GV |
447 | Methods">, below. |
448 | |
449 | =back |
450 | |
451 | =head2 Functions Returning C<B::OP> objects or for walking op trees |
452 | |
3d036c2b |
453 | For descriptions of the class hierarchy of these objects and the |
85cf7f2e |
454 | methods that can be called on them, see below, L<"OVERVIEW OF |
455 | CLASSES"> and L<"OP-RELATED CLASSES">. |
456 | |
457 | =over 4 |
458 | |
459 | =item main_root |
460 | |
461 | Returns the root op (i.e. an object in the appropriate B::OP-derived |
462 | class) of the main part of the Perl program. |
463 | |
464 | =item main_start |
465 | |
466 | Returns the starting op of the main part of the Perl program. |
467 | |
468 | =item walkoptree(OP, METHOD) |
469 | |
470 | Does a tree-walk of the syntax tree based at OP and calls METHOD on |
471 | each op it visits. Each node is visited before its children. If |
472 | C<walkoptree_debug> (see below) has been called to turn debugging on then |
473 | the method C<walkoptree_debug> is called on each op before METHOD is |
474 | called. |
475 | |
476 | =item walkoptree_debug(DEBUG) |
477 | |
478 | Returns the current debugging flag for C<walkoptree>. If the optional |
479 | DEBUG argument is non-zero, it sets the debugging flag to that. See |
480 | the description of C<walkoptree> above for what the debugging flag |
481 | does. |
482 | |
483 | =back |
484 | |
485 | =head2 Miscellaneous Utility Functions |
486 | |
487 | =over 4 |
488 | |
489 | =item ppname(OPNUM) |
490 | |
491 | Return the PP function name (e.g. "pp_add") of op number OPNUM. |
492 | |
493 | =item hash(STR) |
494 | |
495 | Returns a string in the form "0x..." representing the value of the |
496 | internal hash function used by perl on string STR. |
497 | |
498 | =item cast_I32(I) |
499 | |
500 | Casts I to the internal I32 type used by that perl. |
501 | |
502 | =item minus_c |
503 | |
504 | Does the equivalent of the C<-c> command-line option. Obviously, this |
505 | is only useful in a BEGIN block or else the flag is set too late. |
506 | |
507 | =item cstring(STR) |
508 | |
509 | Returns a double-quote-surrounded escaped version of STR which can |
510 | be used as a string in C source code. |
511 | |
512 | =item perlstring(STR) |
513 | |
514 | Returns a double-quote-surrounded escaped version of STR which can |
515 | be used as a string in Perl source code. |
516 | |
517 | =item class(OBJ) |
518 | |
519 | Returns the class of an object without the part of the classname |
520 | preceding the first C<"::">. This is used to turn C<"B::UNOP"> into |
521 | C<"UNOP"> for example. |
522 | |
523 | =item threadsv_names |
524 | |
525 | In a perl compiled for threads, this returns a list of the special |
526 | per-thread threadsv variables. |
527 | |
528 | =back |
529 | |
baccf54f |
530 | =head2 Exported utility variabiles |
531 | |
532 | =over 4 |
533 | |
534 | =item @optype |
535 | |
536 | my $op_type = $optype[$op_type_num]; |
85cf7f2e |
537 | |
baccf54f |
538 | A simple mapping of the op type number to its type (like 'COP' or 'BINOP'). |
539 | |
540 | =item @specialsv_name |
541 | |
542 | my $sv_name = $specialsv_name[$sv_index]; |
543 | |
544 | Certain SV types are considered 'special'. They're represented by |
545 | B::SPECIAL and are referred to by a number from the specialsv_list. |
546 | This array maps that number back to the name of the SV (like 'Nullsv' |
547 | or '&PL_sv_undef'). |
548 | |
549 | =back |
85cf7f2e |
550 | |
551 | |
1a52ab62 |
552 | =head1 OVERVIEW OF CLASSES |
553 | |
554 | The C structures used by Perl's internals to hold SV and OP |
555 | information (PVIV, AV, HV, ..., OP, SVOP, UNOP, ...) are modelled on a |
556 | class hierarchy and the C<B> module gives access to them via a true |
557 | object hierarchy. Structure fields which point to other objects |
558 | (whether types of SV or types of OP) are represented by the C<B> |
85cf7f2e |
559 | module as Perl objects of the appropriate class. |
560 | |
561 | The bulk of the C<B> module is the methods for accessing fields of |
562 | these structures. |
563 | |
564 | Note that all access is read-only. You cannot modify the internals by |
f31c3107 |
565 | using this module. Also, note that the B::OP and B::SV objects created |
566 | by this module are only valid for as long as the underlying objects |
567 | exist; their creation doesn't increase the reference counts of the |
568 | underlying objects. Trying to access the fields of a freed object will |
569 | give incomprehensible results, or worse. |
1a52ab62 |
570 | |
571 | =head2 SV-RELATED CLASSES |
572 | |
573 | B::IV, B::NV, B::RV, B::PV, B::PVIV, B::PVNV, B::PVMG, B::BM, B::PVLV, |
574 | B::AV, B::HV, B::CV, B::GV, B::FM, B::IO. These classes correspond in |
575 | the obvious way to the underlying C structures of similar names. The |
a01b8a53 |
576 | inheritance hierarchy mimics the underlying C "inheritance". For 5.9.1 |
577 | and later this is: |
85cf7f2e |
578 | |
579 | B::SV |
580 | | |
4edc9001 |
581 | +--------------+----------+------------+ |
582 | | | | | |
583 | B::PV B::IV B::NV B::RV |
b591c46e |
584 | \ / / |
585 | \ / / |
586 | B::PVIV / |
587 | \ / |
588 | \ / |
589 | \ / |
590 | B::PVNV |
591 | | |
592 | | |
593 | B::PVMG |
594 | | |
595 | +-----+----+------+-----+-----+ |
596 | | | | | | | |
597 | B::BM B::AV B::GV B::HV B::CV B::IO |
598 | | | |
599 | B::PVLV | |
600 | B::FM |
85cf7f2e |
601 | |
602 | |
a01b8a53 |
603 | For 5.9.0 and earlier, PVLV is a direct subclass of PVMG, so the base |
604 | of this diagram is |
f5ba1307 |
605 | |
606 | | |
607 | B::PVMG |
608 | | |
609 | +------+-----+----+------+-----+-----+ |
610 | | | | | | | | |
611 | B::PVLV B::BM B::AV B::GV B::HV B::CV B::IO |
612 | | |
613 | | |
614 | B::FM |
615 | |
616 | |
85cf7f2e |
617 | Access methods correspond to the underlying C macros for field access, |
1a52ab62 |
618 | usually with the leading "class indication" prefix removed (Sv, Av, |
619 | Hv, ...). The leading prefix is only left in cases where its removal |
620 | would cause a clash in method name. For example, C<GvREFCNT> stays |
621 | as-is since its abbreviation would clash with the "superclass" method |
622 | C<REFCNT> (corresponding to the C function C<SvREFCNT>). |
623 | |
85cf7f2e |
624 | =head2 B::SV Methods |
1a52ab62 |
625 | |
626 | =over 4 |
627 | |
628 | =item REFCNT |
629 | |
630 | =item FLAGS |
631 | |
429a5ce7 |
632 | =item object_2svref |
633 | |
634 | Returns a reference to the regular scalar corresponding to this |
635 | B::SV object. In other words, this method is the inverse operation |
636 | to the svref_2object() subroutine. This scalar and other data it points |
637 | at should be considered read-only: modifying them is neither safe nor |
638 | guaranteed to have a sensible effect. |
639 | |
1a52ab62 |
640 | =back |
641 | |
85cf7f2e |
642 | =head2 B::IV Methods |
1a52ab62 |
643 | |
644 | =over 4 |
645 | |
646 | =item IV |
647 | |
d9963e60 |
648 | Returns the value of the IV, I<interpreted as |
649 | a signed integer>. This will be misleading |
650 | if C<FLAGS & SVf_IVisUV>. Perhaps you want the |
651 | C<int_value> method instead? |
652 | |
1a52ab62 |
653 | =item IVX |
654 | |
d9963e60 |
655 | =item UVX |
656 | |
657 | =item int_value |
658 | |
659 | This method returns the value of the IV as an integer. |
660 | It differs from C<IV> in that it returns the correct |
661 | value regardless of whether it's stored signed or |
662 | unsigned. |
663 | |
1a52ab62 |
664 | =item needs64bits |
665 | |
666 | =item packiv |
667 | |
668 | =back |
669 | |
85cf7f2e |
670 | =head2 B::NV Methods |
1a52ab62 |
671 | |
672 | =over 4 |
673 | |
674 | =item NV |
675 | |
676 | =item NVX |
677 | |
678 | =back |
679 | |
85cf7f2e |
680 | =head2 B::RV Methods |
1a52ab62 |
681 | |
682 | =over 4 |
683 | |
684 | =item RV |
685 | |
686 | =back |
687 | |
85cf7f2e |
688 | =head2 B::PV Methods |
1a52ab62 |
689 | |
690 | =over 4 |
691 | |
692 | =item PV |
693 | |
76ef7183 |
694 | This method is the one you usually want. It constructs a |
695 | string using the length and offset information in the struct: |
696 | for ordinary scalars it will return the string that you'd see |
697 | from Perl, even if it contains null characters. |
698 | |
9d2bbe64 |
699 | =item RV |
700 | |
701 | Same as B::RV::RV, except that it will die() if the PV isn't |
702 | a reference. |
703 | |
0b40bd6d |
704 | =item PVX |
705 | |
76ef7183 |
706 | This method is less often useful. It assumes that the string |
707 | stored in the struct is null-terminated, and disregards the |
708 | length information. |
709 | |
710 | It is the appropriate method to use if you need to get the name |
711 | of a lexical variable from a padname array. Lexical variable names |
712 | are always stored with a null terminator, and the length field |
713 | (SvCUR) is overloaded for other purposes and can't be relied on here. |
714 | |
1a52ab62 |
715 | =back |
716 | |
85cf7f2e |
717 | =head2 B::PVMG Methods |
1a52ab62 |
718 | |
719 | =over 4 |
720 | |
721 | =item MAGIC |
722 | |
723 | =item SvSTASH |
724 | |
725 | =back |
726 | |
85cf7f2e |
727 | =head2 B::MAGIC Methods |
1a52ab62 |
728 | |
729 | =over 4 |
730 | |
731 | =item MOREMAGIC |
732 | |
9d2bbe64 |
733 | =item precomp |
734 | |
735 | Only valid on r-magic, returns the string that generated the regexp. |
736 | |
1a52ab62 |
737 | =item PRIVATE |
738 | |
739 | =item TYPE |
740 | |
741 | =item FLAGS |
742 | |
743 | =item OBJ |
744 | |
9d2bbe64 |
745 | Will die() if called on r-magic. |
746 | |
1a52ab62 |
747 | =item PTR |
748 | |
9d2bbe64 |
749 | =item REGEX |
750 | |
751 | Only valid on r-magic, returns the integer value of the REGEX stored |
752 | in the MAGIC. |
753 | |
1a52ab62 |
754 | =back |
755 | |
85cf7f2e |
756 | =head2 B::PVLV Methods |
1a52ab62 |
757 | |
758 | =over 4 |
759 | |
760 | =item TARGOFF |
761 | |
762 | =item TARGLEN |
763 | |
764 | =item TYPE |
765 | |
766 | =item TARG |
767 | |
768 | =back |
769 | |
85cf7f2e |
770 | =head2 B::BM Methods |
1a52ab62 |
771 | |
772 | =over 4 |
773 | |
774 | =item USEFUL |
775 | |
776 | =item PREVIOUS |
777 | |
778 | =item RARE |
779 | |
780 | =item TABLE |
781 | |
782 | =back |
783 | |
85cf7f2e |
784 | =head2 B::GV Methods |
1a52ab62 |
785 | |
786 | =over 4 |
787 | |
87d7fd28 |
788 | =item is_empty |
789 | |
790 | This method returns TRUE if the GP field of the GV is NULL. |
791 | |
1a52ab62 |
792 | =item NAME |
793 | |
002b978b |
794 | =item SAFENAME |
795 | |
796 | This method returns the name of the glob, but if the first |
797 | character of the name is a control character, then it converts |
798 | it to ^X first, so that *^G would return "^G" rather than "\cG". |
799 | |
800 | It's useful if you want to print out the name of a variable. |
801 | If you restrict yourself to globs which exist at compile-time |
802 | then the result ought to be unambiguous, because code like |
803 | C<${"^G"} = 1> is compiled as two ops - a constant string and |
804 | a dereference (rv2gv) - so that the glob is created at runtime. |
805 | |
806 | If you're working with globs at runtime, and need to disambiguate |
807 | *^G from *{"^G"}, then you should use the raw NAME method. |
808 | |
1a52ab62 |
809 | =item STASH |
810 | |
811 | =item SV |
812 | |
813 | =item IO |
814 | |
815 | =item FORM |
816 | |
817 | =item AV |
818 | |
819 | =item HV |
820 | |
821 | =item EGV |
822 | |
823 | =item CV |
824 | |
825 | =item CVGEN |
826 | |
827 | =item LINE |
828 | |
b195d487 |
829 | =item FILE |
830 | |
1a52ab62 |
831 | =item FILEGV |
832 | |
833 | =item GvREFCNT |
834 | |
835 | =item FLAGS |
836 | |
837 | =back |
838 | |
85cf7f2e |
839 | =head2 B::IO Methods |
1a52ab62 |
840 | |
841 | =over 4 |
842 | |
843 | =item LINES |
844 | |
845 | =item PAGE |
846 | |
847 | =item PAGE_LEN |
848 | |
849 | =item LINES_LEFT |
850 | |
851 | =item TOP_NAME |
852 | |
853 | =item TOP_GV |
854 | |
855 | =item FMT_NAME |
856 | |
857 | =item FMT_GV |
858 | |
859 | =item BOTTOM_NAME |
860 | |
861 | =item BOTTOM_GV |
862 | |
863 | =item SUBPROCESS |
864 | |
865 | =item IoTYPE |
866 | |
867 | =item IoFLAGS |
868 | |
9d2bbe64 |
869 | =item IsSTD |
870 | |
871 | Takes one arguments ( 'stdin' | 'stdout' | 'stderr' ) and returns true |
872 | if the IoIFP of the object is equal to the handle whose name was |
873 | passed as argument ( i.e. $io->IsSTD('stderr') is true if |
874 | IoIFP($io) == PerlIO_stdin() ). |
875 | |
1a52ab62 |
876 | =back |
877 | |
85cf7f2e |
878 | =head2 B::AV Methods |
1a52ab62 |
879 | |
880 | =over 4 |
881 | |
882 | =item FILL |
883 | |
884 | =item MAX |
885 | |
1a52ab62 |
886 | =item ARRAY |
887 | |
429a5ce7 |
888 | =item ARRAYelt |
889 | |
890 | Like C<ARRAY>, but takes an index as an argument to get only one element, |
891 | rather than a list of all of them. |
892 | |
edcc7c74 |
893 | =item OFF |
894 | |
895 | This method is deprecated if running under Perl 5.8, and is no longer present |
896 | if running under Perl 5.9 |
897 | |
898 | =item AvFLAGS |
899 | |
900 | This method returns the AV specific flags. In Perl 5.9 these are now stored |
901 | in with the main SV flags, so this method is no longer present. |
902 | |
1a52ab62 |
903 | =back |
904 | |
85cf7f2e |
905 | =head2 B::CV Methods |
1a52ab62 |
906 | |
907 | =over 4 |
908 | |
909 | =item STASH |
910 | |
911 | =item START |
912 | |
913 | =item ROOT |
914 | |
915 | =item GV |
916 | |
57843af0 |
917 | =item FILE |
918 | |
1a52ab62 |
919 | =item DEPTH |
920 | |
921 | =item PADLIST |
922 | |
923 | =item OUTSIDE |
924 | |
a3985cdc |
925 | =item OUTSIDE_SEQ |
926 | |
1a52ab62 |
927 | =item XSUB |
928 | |
929 | =item XSUBANY |
930 | |
9d2bbe64 |
931 | For constant subroutines, returns the constant SV returned by the subroutine. |
932 | |
5cfd8ad4 |
933 | =item CvFLAGS |
934 | |
de3f1649 |
935 | =item const_sv |
936 | |
1a52ab62 |
937 | =back |
938 | |
85cf7f2e |
939 | =head2 B::HV Methods |
1a52ab62 |
940 | |
941 | =over 4 |
942 | |
943 | =item FILL |
944 | |
945 | =item MAX |
946 | |
947 | =item KEYS |
948 | |
949 | =item RITER |
950 | |
951 | =item NAME |
952 | |
1a52ab62 |
953 | =item ARRAY |
954 | |
edcc7c74 |
955 | =item PMROOT |
956 | |
957 | This method is not present if running under Perl 5.9, as the PMROOT |
958 | information is no longer stored directly in the hash. |
959 | |
1a52ab62 |
960 | =back |
961 | |
962 | =head2 OP-RELATED CLASSES |
963 | |
85cf7f2e |
964 | C<B::OP>, C<B::UNOP>, C<B::BINOP>, C<B::LOGOP>, C<B::LISTOP>, C<B::PMOP>, |
651aa52e |
965 | C<B::SVOP>, C<B::PADOP>, C<B::PVOP>, C<B::LOOP>, C<B::COP>. |
85cf7f2e |
966 | |
967 | These classes correspond in the obvious way to the underlying C |
968 | structures of similar names. The inheritance hierarchy mimics the |
969 | underlying C "inheritance": |
970 | |
971 | B::OP |
972 | | |
5ce57cc0 |
973 | +---------------+--------+--------+-------+ |
974 | | | | | | |
975 | B::UNOP B::SVOP B::PADOP B::COP B::PVOP |
85cf7f2e |
976 | ,' `-. |
977 | / `--. |
978 | B::BINOP B::LOGOP |
979 | | |
980 | | |
981 | B::LISTOP |
982 | ,' `. |
983 | / \ |
984 | B::LOOP B::PMOP |
985 | |
986 | Access methods correspond to the underlying C structre field names, |
987 | with the leading "class indication" prefix (C<"op_">) removed. |
988 | |
989 | =head2 B::OP Methods |
1a52ab62 |
990 | |
a60ba18b |
991 | These methods get the values of similarly named fields within the OP |
992 | data structure. See top of C<op.h> for more info. |
993 | |
1a52ab62 |
994 | =over 4 |
995 | |
996 | =item next |
997 | |
998 | =item sibling |
999 | |
3f872cb9 |
1000 | =item name |
1001 | |
1002 | This returns the op name as a string (e.g. "add", "rv2av"). |
1003 | |
1a52ab62 |
1004 | =item ppaddr |
1005 | |
dc333d64 |
1006 | This returns the function name as a string (e.g. "PL_ppaddr[OP_ADD]", |
1007 | "PL_ppaddr[OP_RV2AV]"). |
1a52ab62 |
1008 | |
1009 | =item desc |
1010 | |
4369b173 |
1011 | This returns the op description from the global C PL_op_desc array |
1a52ab62 |
1012 | (e.g. "addition" "array deref"). |
1013 | |
1014 | =item targ |
1015 | |
1016 | =item type |
1017 | |
a60ba18b |
1018 | =item opt |
1019 | |
1a52ab62 |
1020 | =item flags |
1021 | |
1022 | =item private |
1023 | |
a60ba18b |
1024 | =item spare |
1025 | |
1a52ab62 |
1026 | =back |
1027 | |
1028 | =head2 B::UNOP METHOD |
1029 | |
1030 | =over 4 |
1031 | |
1032 | =item first |
1033 | |
1034 | =back |
1035 | |
1036 | =head2 B::BINOP METHOD |
1037 | |
1038 | =over 4 |
1039 | |
1040 | =item last |
1041 | |
1042 | =back |
1043 | |
1044 | =head2 B::LOGOP METHOD |
1045 | |
1046 | =over 4 |
1047 | |
1048 | =item other |
1049 | |
1050 | =back |
1051 | |
1a52ab62 |
1052 | =head2 B::LISTOP METHOD |
1053 | |
1054 | =over 4 |
1055 | |
1056 | =item children |
1057 | |
1058 | =back |
1059 | |
85cf7f2e |
1060 | =head2 B::PMOP Methods |
1a52ab62 |
1061 | |
1062 | =over 4 |
1063 | |
1064 | =item pmreplroot |
1065 | |
1066 | =item pmreplstart |
1067 | |
1068 | =item pmnext |
1069 | |
1070 | =item pmregexp |
1071 | |
1072 | =item pmflags |
1073 | |
c737faaf |
1074 | =item extflags |
1a52ab62 |
1075 | |
1076 | =item precomp |
1077 | |
651aa52e |
1078 | =item pmoffset |
9d2bbe64 |
1079 | |
1080 | Only when perl was compiled with ithreads. |
1081 | |
1a52ab62 |
1082 | =back |
1083 | |
1084 | =head2 B::SVOP METHOD |
1085 | |
1086 | =over 4 |
1087 | |
1088 | =item sv |
1089 | |
065a1863 |
1090 | =item gv |
1091 | |
1a52ab62 |
1092 | =back |
1093 | |
7934575e |
1094 | =head2 B::PADOP METHOD |
1a52ab62 |
1095 | |
1096 | =over 4 |
1097 | |
7934575e |
1098 | =item padix |
1a52ab62 |
1099 | |
1100 | =back |
1101 | |
1102 | =head2 B::PVOP METHOD |
1103 | |
1104 | =over 4 |
1105 | |
1106 | =item pv |
1107 | |
1108 | =back |
1109 | |
85cf7f2e |
1110 | =head2 B::LOOP Methods |
1a52ab62 |
1111 | |
1112 | =over 4 |
1113 | |
1114 | =item redoop |
1115 | |
1116 | =item nextop |
1117 | |
1118 | =item lastop |
1119 | |
1120 | =back |
1121 | |
85cf7f2e |
1122 | =head2 B::COP Methods |
1a52ab62 |
1123 | |
1124 | =over 4 |
1125 | |
1126 | =item label |
1127 | |
1128 | =item stash |
1129 | |
6e6a1aef |
1130 | =item stashpv |
1131 | |
57843af0 |
1132 | =item file |
1a52ab62 |
1133 | |
1134 | =item cop_seq |
1135 | |
1136 | =item arybase |
1137 | |
1138 | =item line |
1139 | |
6e6a1aef |
1140 | =item warnings |
1141 | |
1142 | =item io |
1143 | |
d5ec2987 |
1144 | =item hints |
1145 | |
1a52ab62 |
1146 | =back |
1147 | |
7f20e9dd |
1148 | |
1149 | =head1 AUTHOR |
1150 | |
1151 | Malcolm Beattie, C<mbeattie@sable.ox.ac.uk> |
1152 | |
1153 | =cut |