2 # Copyright (C) 2000-2003 Stephen McCamant. All rights reserved.
3 # This program is free software; you can redistribute and/or modify it
4 # under the same terms as Perl itself.
6 # Note: we need to keep track of how many use declarations/BEGIN
7 # blocks this module uses, so we can avoid printing them when user
8 # asks for the BEGIN blocks in her program. Update the comments and
9 # the count in concise_specials if you add or delete one. The
10 # -MO=Concise counts as use #1.
13 use warnings; # uses #3 and #4, since warnings uses Carp
15 use Exporter (); # use #5
17 our $VERSION = "0.66";
18 our @ISA = qw(Exporter);
19 our @EXPORT_OK = qw( set_style set_style_standard add_callback
20 concise_subref concise_cv concise_main
21 add_style walk_output compile reset_sequence );
23 ( io => [qw( walk_output compile reset_sequence )],
24 style => [qw( add_style set_style_standard )],
25 cb => [qw( add_callback )],
26 mech => [qw( concise_subref concise_cv concise_main )], );
29 use B qw(class ppname main_start main_root main_cv cstring svref_2object
30 SVf_IOK SVf_NOK SVf_POK SVf_IVisUV SVf_FAKE OPf_KIDS OPf_SPECIAL
35 ["(?(#label =>\n)?)(*( )*)#class (#addr) #name (?([#targ])?) "
36 . "#svclass~(?((#svaddr))?)~#svval~(?(label \"#coplabel\")?)\n",
37 "(*( )*)goto #class (#addr)\n",
40 ["#hyphseq2 (*( (x( ;)x))*)<#classsym> "
41 . "#exname#arg(?([#targarglife])?)~#flags(?(/#private)?)(x(;~->#next)x)\n"
42 , " (*( )*) goto #seq\n",
43 "(?(<#seq>)?)#exname#arg(?([#targarglife])?)"],
45 ["(x(;(*( )*))x)#noise#arg(?([#targarg])?)(x( ;\n)x)",
47 "(?(#seq)?)#noise#arg(?([#targarg])?)"],
49 ["#class (#addr)\n\top_next\t\t#nextaddr\n\top_sibling\t#sibaddr\n\t"
50 . "op_ppaddr\tPL_ppaddr[OP_#NAME]\n\top_type\t\t#typenum\n" .
51 ($] > 5.009 ? '' : "\top_seq\t\t#seqnum\n")
52 . "\top_flags\t#flagval\n\top_private\t#privval\n"
53 . "(?(\top_first\t#firstaddr\n)?)(?(\top_last\t\t#lastaddr\n)?)"
54 . "(?(\top_sv\t\t#svaddr\n)?)",
57 "env" => [$ENV{B_CONCISE_FORMAT}, $ENV{B_CONCISE_GOTO_FORMAT},
58 $ENV{B_CONCISE_TREE_FORMAT}],
61 # Renderings, ie how Concise prints, is controlled by these vars
63 our $stylename; # selects current style from %style
64 my $order = "basic"; # how optree is walked & printed: basic, exec, tree
66 # rendering mechanics:
67 # these 'formats' are the line-rendering templates
68 # they're updated from %style when $stylename changes
69 my ($format, $gotofmt, $treefmt);
72 my $base = 36; # how <sequence#> is displayed
73 my $big_endian = 1; # more <sequence#> display
74 my $tree_style = 0; # tree-order details
75 my $banner = 1; # print banner before optree is traversed
76 my $do_main = 0; # force printing of main routine
78 # another factor: can affect all styles!
79 our @callbacks; # allow external management
81 set_style_standard("concise");
87 ($format, $gotofmt, $treefmt) = @_;
88 #warn "set_style: deprecated, use set_style_standard instead\n"; # someday
89 die "expecting 3 style-format args\n" unless @_ == 3;
93 my ($newstyle,@args) = @_;
94 die "style '$newstyle' already exists, choose a new name\n"
95 if exists $style{$newstyle};
96 die "expecting 3 style-format args\n" unless @args == 3;
97 $style{$newstyle} = [@args];
98 $stylename = $newstyle; # update rendering state
101 sub set_style_standard {
102 ($stylename) = @_; # update rendering state
103 die "err: style '$stylename' unknown\n" unless exists $style{$stylename};
104 set_style(@{$style{$stylename}});
111 # output handle, used with all Concise-output printing
112 our $walkHandle; # public for your convenience
113 BEGIN { $walkHandle = \*STDOUT }
115 sub walk_output { # updates $walkHandle
117 return $walkHandle unless $handle; # allow use as accessor
119 if (ref $handle eq 'SCALAR') {
121 die "no perlio in this build, can't call walk_output (\\\$scalar)\n"
122 unless $Config::Config{useperlio};
123 # in 5.8+, open(FILEHANDLE,MODE,REFERENCE) writes to string
124 open my $tmp, '>', $handle; # but cant re-set existing STDOUT
125 $walkHandle = $tmp; # so use my $tmp as intermediate var
128 my $iotype = ref $handle;
129 die "expecting argument/object that can print\n"
130 unless $iotype eq 'GLOB' or $iotype and $handle->can('print');
131 $walkHandle = $handle;
135 my($order, $coderef, $name) = @_;
136 my $codeobj = svref_2object($coderef);
138 return concise_stashref(@_)
139 unless ref $codeobj eq 'B::CV';
140 concise_cv_obj($order, $codeobj, $name);
143 sub concise_stashref {
145 foreach my $k (sort keys %$h) {
147 my $coderef = *s{CODE} or next;
149 print "FUNC: ", *s, "\n";
150 my $codeobj = svref_2object($coderef);
151 next unless ref $codeobj eq 'B::CV';
152 eval { concise_cv_obj($order, $codeobj) }
153 or warn "err $@ on $codeobj";
157 # This should have been called concise_subref, but it was exported
158 # under this name in versions before 0.56
159 *concise_cv = \&concise_subref;
162 my ($order, $cv, $name) = @_;
163 # name is either a string, or a CODE ref (copy of $cv arg??)
167 print $walkHandle "$name is XS code\n";
170 if (class($cv->START) eq "NULL") {
172 if (ref $name eq 'CODE') {
173 print $walkHandle "coderef $name has no START\n";
175 elsif (exists &$name) {
176 print $walkHandle "$name exists in stash, but has no START\n";
179 print $walkHandle "$name not in symbol table\n";
183 sequence($cv->START);
184 if ($order eq "exec") {
185 walk_exec($cv->START);
187 elsif ($order eq "basic") {
188 # walk_topdown($cv->ROOT, sub { $_[0]->concise($_[1]) }, 0);
189 my $root = $cv->ROOT;
190 unless (ref $root eq 'B::NULL') {
191 walk_topdown($root, sub { $_[0]->concise($_[1]) }, 0);
193 print $walkHandle "B::NULL encountered doing ROOT on $cv. avoiding disaster\n";
196 print $walkHandle tree($cv->ROOT, 0);
202 sequence(main_start);
204 if ($order eq "exec") {
205 return if class(main_start) eq "NULL";
206 walk_exec(main_start);
207 } elsif ($order eq "tree") {
208 return if class(main_root) eq "NULL";
209 print $walkHandle tree(main_root, 0);
210 } elsif ($order eq "basic") {
211 return if class(main_root) eq "NULL";
212 walk_topdown(main_root,
213 sub { $_[0]->concise($_[1]) }, 0);
217 sub concise_specials {
218 my($name, $order, @cv_s) = @_;
220 if ($name eq "BEGIN") {
221 splice(@cv_s, 0, 8); # skip 7 BEGIN blocks in this file. NOW 8 ??
222 } elsif ($name eq "CHECK") {
223 pop @cv_s; # skip the CHECK block that calls us
226 print $walkHandle "$name $i:\n";
228 concise_cv_obj($order, $cv, $name);
232 my $start_sym = "\e(0"; # "\cN" sometimes also works
233 my $end_sym = "\e(B"; # "\cO" respectively
235 my @tree_decorations =
236 ([" ", "--", "+-", "|-", "| ", "`-", "-", 1],
237 [" ", "-", "+", "+", "|", "`", "", 0],
238 [" ", map("$start_sym$_$end_sym", "qq", "wq", "tq", "x ", "mq", "q"), 1],
239 [" ", map("$start_sym$_$end_sym", "q", "w", "t", "x", "m"), "", 0],
244 # set rendering state from options and args
247 @options = grep(/^-/, @_);
248 @args = grep(!/^-/, @_);
250 for my $o (@options) {
252 if ($o eq "-basic") {
254 } elsif ($o eq "-exec") {
256 } elsif ($o eq "-tree") {
260 elsif ($o eq "-compact") {
262 } elsif ($o eq "-loose") {
264 } elsif ($o eq "-vt") {
266 } elsif ($o eq "-ascii") {
270 elsif ($o =~ /^-base(\d+)$/) {
272 } elsif ($o eq "-bigendian") {
274 } elsif ($o eq "-littleendian") {
277 elsif ($o eq "-nobanner") {
279 } elsif ($o eq "-banner") {
282 elsif ($o eq "-main") {
284 } elsif ($o eq "-nomain") {
288 elsif (exists $style{substr($o, 1)}) {
289 $stylename = substr($o, 1);
290 set_style_standard($stylename);
292 warn "Option $o unrecognized";
299 my (@args) = compileOpts(@_);
301 my @newargs = compileOpts(@_); # accept new rendering options
302 warn "disregarding non-options: @newargs\n" if @newargs;
304 for my $objname (@args) {
305 next unless $objname; # skip null args to avoid noisy responses
307 if ($objname eq "BEGIN") {
308 concise_specials("BEGIN", $order,
309 B::begin_av->isa("B::AV") ?
310 B::begin_av->ARRAY : ());
311 } elsif ($objname eq "INIT") {
312 concise_specials("INIT", $order,
313 B::init_av->isa("B::AV") ?
314 B::init_av->ARRAY : ());
315 } elsif ($objname eq "CHECK") {
316 concise_specials("CHECK", $order,
317 B::check_av->isa("B::AV") ?
318 B::check_av->ARRAY : ());
319 } elsif ($objname eq "END") {
320 concise_specials("END", $order,
321 B::end_av->isa("B::AV") ?
322 B::end_av->ARRAY : ());
325 # convert function names to subrefs
328 print $walkHandle "B::Concise::compile($objname)\n"
332 $objname = "main::" . $objname unless $objname =~ /::/;
333 print $walkHandle "$objname:\n";
335 unless (exists &$objname) {
336 print $walkHandle "err: unknown function ($objname)\n";
339 $objref = \&$objname;
341 concise_subref($order, $objref, $objname);
344 if (!@args or $do_main) {
345 print $walkHandle "main program:\n" if $do_main;
346 concise_main($order);
348 return @args; # something
353 my $lastnext; # remembers op-chain, used to insert gotos
355 my %opclass = ('OP' => "0", 'UNOP' => "1", 'BINOP' => "2", 'LOGOP' => "|",
356 'LISTOP' => "@", 'PMOP' => "/", 'SVOP' => "\$", 'GVOP' => "*",
357 'PVOP' => '"', 'LOOP' => "{", 'COP' => ";", 'PADOP' => "#");
359 no warnings 'qw'; # "Possible attempt to put comments..."; use #7
361 qw'# () sc ( @? 1 $* gv *{ m$ m@ m% m? p/ *$ $ $# & a& pt \\ s\\ rf bl
362 ` *? <> ?? ?/ r/ c/ // qr s/ /c y/ = @= C sC Cp sp df un BM po +1 +I
363 -1 -I 1+ I+ 1- I- ** * i* / i/ %$ i% x + i+ - i- . " << >> < i<
364 > i> <= i, >= i. == i= != i! <? i? s< s> s, s. s= s! s? b& b^ b| -0 -i
365 ! ~ a2 si cs rd sr e^ lg sq in %x %o ab le ss ve ix ri sf FL od ch cy
366 uf lf uc lc qm @ [f [ @[ eh vl ky dl ex % ${ @{ uk pk st jn ) )[ a@
367 a% sl +] -] [- [+ so rv GS GW MS MW .. f. .f && || ^^ ?: &= |= -> s{ s}
368 v} ca wa di rs ;; ; ;d }{ { } {} f{ it {l l} rt }l }n }r dm }g }e ^o
369 ^c ^| ^# um bm t~ u~ ~d DB db ^s se ^g ^r {w }w pf pr ^O ^K ^R ^W ^d ^v
370 ^e ^t ^k t. fc ic fl .s .p .b .c .l .a .h g1 s1 g2 s2 ?. l? -R -W -X -r
371 -w -x -e -o -O -z -s -M -A -C -S -c -b -f -d -p -l -u -g -k -t -T -B cd
372 co cr u. cm ut r. l@ s@ r@ mD uD oD rD tD sD wD cD f$ w$ p$ sh e$ k$ g3
373 g4 s4 g5 s5 T@ C@ L@ G@ A@ S@ Hg Hc Hr Hw Mg Mc Ms Mr Sg Sc So rq do {e
374 e} {t t} g6 G6 6e g7 G7 7e g8 G8 8e g9 G9 9e 6s 7s 8s 9s 6E 7E 8E 9E Pn
375 Pu GP SP EP Gn Gg GG SG EG g0 c$ lk t$ ;s n> // /= CO';
377 my $chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
379 sub op_flags { # common flags (see BASOP.op_flags in op.h)
382 push @v, "v" if ($x & 3) == 1;
383 push @v, "s" if ($x & 3) == 2;
384 push @v, "l" if ($x & 3) == 3;
385 push @v, "K" if $x & 4;
386 push @v, "P" if $x & 8;
387 push @v, "R" if $x & 16;
388 push @v, "M" if $x & 32;
389 push @v, "S" if $x & 64;
390 push @v, "*" if $x & 128;
396 return "-" . base_n(-$x) if $x < 0;
398 do { $str .= substr($chars, $x % $base, 1) } while $x = int($x / $base);
399 $str = reverse $str if $big_endian;
415 return "-" if not exists $sequence_num{$$op};
416 return base_n($sequence_num{$$op});
420 my($op, $sub, $level) = @_;
422 if ($op->flags & OPf_KIDS) {
423 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
424 walk_topdown($kid, $sub, $level + 1);
427 elsif (class($op) eq "PMOP") {
428 my $maybe_root = $op->pmreplroot;
429 if (ref($maybe_root) and $maybe_root->isa("B::OP")) {
430 # It really is the root of the replacement, not something
431 # else stored here for lack of space elsewhere
432 walk_topdown($maybe_root, $sub, $level + 1);
438 my($ar, $level) = @_;
440 if (ref($l) eq "ARRAY") {
441 walklines($l, $level + 1);
449 my($top, $level) = @_;
452 my @todo = ([$top, \@lines]);
453 while (@todo and my($op, $targ) = @{shift @todo}) {
454 for (; $$op; $op = $op->next) {
455 last if $opsseen{$$op}++;
457 my $name = $op->name;
458 if (class($op) eq "LOGOP") {
461 push @todo, [$op->other, $ar];
462 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
465 push @todo, [$op->pmreplstart, $ar];
466 } elsif ($name =~ /^enter(loop|iter)$/) {
468 $labels{${$op->nextop}} = "NEXT";
469 $labels{${$op->lastop}} = "LAST";
470 $labels{${$op->redoop}} = "REDO";
472 $labels{$op->nextop->seq} = "NEXT";
473 $labels{$op->lastop->seq} = "LAST";
474 $labels{$op->redoop->seq} = "REDO";
479 walklines(\@lines, 0);
482 # The structure of this routine is purposely modeled after op.c's peep()
486 return if class($op) eq "NULL" or exists $sequence_num{$$op};
487 for (; $$op; $op = $op->next) {
488 last if exists $sequence_num{$$op};
489 my $name = $op->name;
490 if ($name =~ /^(null|scalar|lineseq|scope)$/) {
491 next if $oldop and $ {$op->next};
493 $sequence_num{$$op} = $seq_max++;
494 if (class($op) eq "LOGOP") {
495 my $other = $op->other;
496 $other = $other->next while $other->name eq "null";
498 } elsif (class($op) eq "LOOP") {
499 my $redoop = $op->redoop;
500 $redoop = $redoop->next while $redoop->name eq "null";
502 my $nextop = $op->nextop;
503 $nextop = $nextop->next while $nextop->name eq "null";
505 my $lastop = $op->lastop;
506 $lastop = $lastop->next while $lastop->name eq "null";
508 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
509 my $replstart = $op->pmreplstart;
510 $replstart = $replstart->next while $replstart->name eq "null";
511 sequence($replstart);
518 sub fmt_line { # generate text-line for op.
519 my($hr, $op, $text, $level) = @_;
521 $_->($hr, $op, \$text, \$level, $stylename) for @callbacks;
523 return '' if $hr->{SKIP}; # suppress line if a callback said so
524 return '' if $hr->{goto} and $hr->{goto} eq '-'; # no goto nowhere
526 # spec: (?(text1#varText2)?)
527 $text =~ s/\(\?\(([^\#]*?)\#(\w+)([^\#]*?)\)\?\)/
528 $hr->{$2} ? $1.$hr->{$2}.$3 : ""/eg;
530 # spec: (x(exec_text;basic_text)x)
531 $text =~ s/\(x\((.*?);(.*?)\)x\)/$order eq "exec" ? $1 : $2/egs;
534 $text =~ s/\(\*\(([^;]*?)\)\*\)/$1 x $level/egs;
536 # spec: (*(text1;text2)*)
537 $text =~ s/\(\*\((.*?);(.*?)\)\*\)/$1 x ($level - 1) . $2 x ($level>0)/egs;
539 # convert #Var to tag=>val form: Var\t#var
540 $text =~ s/\#([A-Z][a-z]+)(\d+)?/\t\u$1\t\L#$1$2/gs;
543 $text =~ s/\#([a-zA-Z]+)(\d+)/sprintf("%-$2s", $hr->{$1})/eg;
545 $text =~ s/\#([a-zA-Z]+)/$hr->{$1}/eg; # populate #var's
546 $text =~ s/[ \t]*~+[ \t]*/ /g; # squeeze tildes
548 return "$text\n" if $text ne "";
549 return $text; # suppress empty lines
552 our %priv; # used to display each opcode's BASEOP.op_private values
554 $priv{$_}{128} = "LVINTRO"
555 for ("pos", "substr", "vec", "threadsv", "gvsv", "rv2sv", "rv2hv", "rv2gv",
556 "rv2av", "rv2arylen", "aelem", "helem", "aslice", "hslice", "padsv",
557 "padav", "padhv", "enteriter");
558 $priv{$_}{64} = "REFC" for ("leave", "leavesub", "leavesublv", "leavewrite");
559 $priv{"aassign"}{64} = "COMMON";
560 $priv{"aassign"}{32} = "PHASH" if $] < 5.009;
561 $priv{"sassign"}{64} = "BKWARD";
562 $priv{$_}{64} = "RTIME" for ("match", "subst", "substcont");
563 @{$priv{"trans"}}{1,2,4,8,16,64} = ("<UTF", ">UTF", "IDENT", "SQUASH", "DEL",
565 $priv{"repeat"}{64} = "DOLIST";
566 $priv{"leaveloop"}{64} = "CONT";
567 @{$priv{$_}}{32,64,96} = ("DREFAV", "DREFHV", "DREFSV")
568 for (qw(rv2gv rv2sv padsv aelem helem));
569 @{$priv{"entersub"}}{16,32,64} = ("DBG","TARG","NOMOD");
570 @{$priv{$_}}{4,8,128} = ("INARGS","AMPER","NO()") for ("entersub", "rv2cv");
571 $priv{"gv"}{32} = "EARLYCV";
572 $priv{"aelem"}{16} = $priv{"helem"}{16} = "LVDEFER";
573 $priv{$_}{16} = "OURINTR" for ("gvsv", "rv2sv", "rv2av", "rv2hv", "r2gv",
575 $priv{$_}{16} = "TARGMY"
576 for (map(($_,"s$_"),"chop", "chomp"),
577 map(($_,"i_$_"), "postinc", "postdec", "multiply", "divide", "modulo",
578 "add", "subtract", "negate"), "pow", "concat", "stringify",
579 "left_shift", "right_shift", "bit_and", "bit_xor", "bit_or",
580 "complement", "atan2", "sin", "cos", "rand", "exp", "log", "sqrt",
581 "int", "hex", "oct", "abs", "length", "index", "rindex", "sprintf",
582 "ord", "chr", "crypt", "quotemeta", "join", "push", "unshift", "flock",
583 "chdir", "chown", "chroot", "unlink", "chmod", "utime", "rename",
584 "link", "symlink", "mkdir", "rmdir", "wait", "waitpid", "system",
585 "exec", "kill", "getppid", "getpgrp", "setpgrp", "getpriority",
586 "setpriority", "time", "sleep");
587 $priv{$_}{4} = "REVERSED" for ("enteriter", "iter");
588 @{$priv{"const"}}{4,8,16,32,64,128} = ("SHORT","STRICT","ENTERED",'$[',"BARE","WARN");
589 $priv{"flip"}{64} = $priv{"flop"}{64} = "LINENUM";
590 $priv{"list"}{64} = "GUESSED";
591 $priv{"delete"}{64} = "SLICE";
592 $priv{"exists"}{64} = "SUB";
593 $priv{$_}{64} = "LOCALE"
594 for ("sort", "prtf", "sprintf", "slt", "sle", "seq", "sne", "sgt", "sge",
595 "scmp", "lc", "uc", "lcfirst", "ucfirst");
596 @{$priv{"sort"}}{1,2,4,8,16} = ("NUM", "INT", "REV", "INPLACE","DESC");
597 $priv{"threadsv"}{64} = "SVREFd";
598 @{$priv{$_}}{16,32,64,128} = ("INBIN","INCR","OUTBIN","OUTCR")
599 for ("open", "backtick");
600 $priv{"exit"}{128} = "VMS";
601 $priv{$_}{2} = "FTACCESS"
602 for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec");
604 # Stacked filetests are post 5.8.x
605 $priv{$_}{4} = "FTSTACKED"
606 for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec",
607 "ftis", "fteowned", "ftrowned", "ftzero", "ftsize", "ftmtime",
608 "ftatime", "ftctime", "ftsock", "ftchr", "ftblk", "ftfile", "ftdir",
609 "ftpipe", "ftlink", "ftsuid", "ftsgid", "ftsvtx", "fttty", "fttext",
611 # Lexical $_ is post 5.8.x
612 $priv{$_}{2} = "GREPLEX"
613 for ("mapwhile", "mapstart", "grepwhile", "grepstart");
619 for my $flag (128, 96, 64, 32, 16, 8, 4, 2, 1) {
620 if ($priv{$name}{$flag} and $x & $flag and $x >= $flag) {
622 push @s, $priv{$name}{$flag};
626 return join(",", @s);
631 $hr->{svclass} = class($sv);
632 $hr->{svclass} = "UV"
633 if $hr->{svclass} eq "IV" and $sv->FLAGS & SVf_IVisUV;
634 $hr->{svaddr} = sprintf("%#x", $$sv);
635 if ($hr->{svclass} eq "GV") {
637 my $stash = $gv->STASH->NAME;
638 if ($stash eq "main") {
641 $stash = $stash . "::";
643 $hr->{svval} = "*$stash" . $gv->SAFENAME;
644 return "*$stash" . $gv->SAFENAME;
646 while (class($sv) eq "RV") {
647 $hr->{svval} .= "\\";
650 if (class($sv) eq "SPECIAL") {
651 $hr->{svval} .= ["Null", "sv_undef", "sv_yes", "sv_no"]->[$$sv];
652 } elsif ($sv->FLAGS & SVf_NOK) {
653 $hr->{svval} .= $sv->NV;
654 } elsif ($sv->FLAGS & SVf_IOK) {
655 $hr->{svval} .= $sv->int_value;
656 } elsif ($sv->FLAGS & SVf_POK) {
657 $hr->{svval} .= cstring($sv->PV);
658 } elsif (class($sv) eq "HV") {
659 $hr->{svval} .= 'HASH';
662 $hr->{svval} = 'undef' unless defined $hr->{svval};
663 my $out = $hr->{svclass};
664 return $out .= " $hr->{svval}" ;
669 my ($op, $level, $format) = @_;
671 $h{exname} = $h{name} = $op->name;
672 $h{NAME} = uc $h{name};
673 $h{class} = class($op);
674 $h{extarg} = $h{targ} = $op->targ;
675 $h{extarg} = "" unless $h{extarg};
676 if ($h{name} eq "null" and $h{targ}) {
677 # targ holds the old type
678 $h{exname} = "ex-" . substr(ppname($h{targ}), 3);
680 } elsif ($op->name =~ /^leave(sub(lv)?|write)?$/) {
681 # targ potentially holds a reference count
682 if ($op->private & 64) {
683 my $refs = "ref" . ($h{targ} != 1 ? "s" : "");
684 $h{targarglife} = $h{targarg} = "$h{targ} $refs";
687 my $padname = (($curcv->PADLIST->ARRAY)[0]->ARRAY)[$h{targ}];
688 if (defined $padname and class($padname) ne "SPECIAL") {
689 $h{targarg} = $padname->PVX;
690 if ($padname->FLAGS & SVf_FAKE) {
692 $h{targarglife} = "$h{targarg}:FAKE";
694 # These changes relate to the jumbo closure fix.
695 # See changes 19939 and 20005
697 $fake .= 'a' if $padname->IVX & 1; # PAD_FAKELEX_ANON
698 $fake .= 'm' if $padname->IVX & 2; # PAD_FAKELEX_MULTI
699 $fake .= ':' . $padname->NVX if $curcv->CvFLAGS & CVf_ANON;
700 $h{targarglife} = "$h{targarg}:FAKE:$fake";
704 my $intro = $padname->NVX - $cop_seq_base;
705 my $finish = int($padname->IVX) - $cop_seq_base;
706 $finish = "end" if $finish == 999999999 - $cop_seq_base;
707 $h{targarglife} = "$h{targarg}:$intro,$finish";
710 $h{targarglife} = $h{targarg} = "t" . $h{targ};
714 $h{svclass} = $h{svaddr} = $h{svval} = "";
715 if ($h{class} eq "PMOP") {
716 my $precomp = $op->precomp;
717 if (defined $precomp) {
718 $precomp = cstring($precomp); # Escape literal control sequences
719 $precomp = "/$precomp/";
723 my $pmreplroot = $op->pmreplroot;
725 if (ref($pmreplroot) eq "B::GV") {
726 # with C<@stash_array = split(/pat/, str);>,
727 # *stash_array is stored in /pat/'s pmreplroot.
728 $h{arg} = "($precomp => \@" . $pmreplroot->NAME . ")";
729 } elsif (!ref($pmreplroot) and $pmreplroot) {
730 # same as the last case, except the value is actually a
731 # pad offset for where the GV is kept (this happens under
733 my $gv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$pmreplroot];
734 $h{arg} = "($precomp => \@" . $gv->NAME . ")";
735 } elsif ($ {$op->pmreplstart}) {
737 $pmreplstart = "replstart->" . seq($op->pmreplstart);
738 $h{arg} = "(" . join(" ", $precomp, $pmreplstart) . ")";
740 $h{arg} = "($precomp)";
742 } elsif ($h{class} eq "PVOP" and $h{name} ne "trans") {
743 $h{arg} = '("' . $op->pv . '")';
744 $h{svval} = '"' . $op->pv . '"';
745 } elsif ($h{class} eq "COP") {
746 my $label = $op->label;
747 $h{coplabel} = $label;
748 $label = $label ? "$label: " : "";
751 $loc .= ":" . $op->line;
752 my($stash, $cseq) = ($op->stash->NAME, $op->cop_seq - $cop_seq_base);
753 my $arybase = $op->arybase;
754 $arybase = $arybase ? ' $[=' . $arybase : "";
755 $h{arg} = "($label$stash $cseq $loc$arybase)";
756 } elsif ($h{class} eq "LOOP") {
757 $h{arg} = "(next->" . seq($op->nextop) . " last->" . seq($op->lastop)
758 . " redo->" . seq($op->redoop) . ")";
759 } elsif ($h{class} eq "LOGOP") {
761 $h{arg} = "(other->" . seq($op->other) . ")";
762 } elsif ($h{class} eq "SVOP") {
763 unless ($h{name} eq 'aelemfast' and $op->flags & OPf_SPECIAL) {
765 my $sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$op->targ];
766 $h{arg} = "[" . concise_sv($sv, \%h) . "]";
767 $h{targarglife} = $h{targarg} = "";
769 $h{arg} = "(" . concise_sv($op->sv, \%h) . ")";
772 } elsif ($h{class} eq "PADOP") {
773 my $sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$op->padix];
774 $h{arg} = "[" . concise_sv($sv, \%h) . "]";
776 $h{seq} = $h{hyphseq} = seq($op);
777 $h{seq} = "" if $h{seq} eq "-";
780 $h{static} = $op->static;
781 $h{label} = $labels{$$op};
783 $h{seqnum} = $op->seq;
784 $h{label} = $labels{$op->seq};
786 $h{next} = $op->next;
787 $h{next} = (class($h{next}) eq "NULL") ? "(end)" : seq($h{next});
788 $h{nextaddr} = sprintf("%#x", $ {$op->next});
789 $h{sibaddr} = sprintf("%#x", $ {$op->sibling});
790 $h{firstaddr} = sprintf("%#x", $ {$op->first}) if $op->can("first");
791 $h{lastaddr} = sprintf("%#x", $ {$op->last}) if $op->can("last");
793 $h{classsym} = $opclass{$h{class}};
794 $h{flagval} = $op->flags;
795 $h{flags} = op_flags($op->flags);
796 $h{privval} = $op->private;
797 $h{private} = private_flags($h{name}, $op->private);
798 $h{addr} = sprintf("%#x", $$op);
799 $h{typenum} = $op->type;
800 $h{noise} = $linenoise[$op->type];
802 return fmt_line(\%h, $op, $format, $level);
806 my($op, $level) = @_;
807 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
808 # insert a 'goto' line
809 my $synth = {"seq" => seq($lastnext), "class" => class($lastnext),
810 "addr" => sprintf("%#x", $$lastnext),
811 "goto" => seq($lastnext), # simplify goto '-' removal
813 print $walkHandle fmt_line($synth, $op, $gotofmt, $level+1);
815 $lastnext = $op->next;
816 print $walkHandle concise_op($op, $level, $format);
819 # B::OP::terse (see Terse.pm) now just calls this
821 my($op, $level) = @_;
823 # This isn't necessarily right, but there's no easy way to get
824 # from an OP to the right CV. This is a limitation of the
825 # ->terse() interface style, and there isn't much to do about
826 # it. In particular, we can die in concise_op if the main pad
827 # isn't long enough, or has the wrong kind of entries, compared to
828 # the pad a sub was compiled with. The fix for that would be to
829 # make a backwards compatible "terse" format that never even
830 # looked at the pad, just like the old B::Terse. I don't think
831 # that's worth the effort, though.
832 $curcv = main_cv unless $curcv;
834 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
836 my $h = {"seq" => seq($lastnext), "class" => class($lastnext),
837 "addr" => sprintf("%#x", $$lastnext)};
839 fmt_line($h, $op, $style{"terse"}[1], $level+1);
841 $lastnext = $op->next;
843 concise_op($op, $level, $style{"terse"}[0]);
849 my $style = $tree_decorations[$tree_style];
850 my($space, $single, $kids, $kid, $nokid, $last, $lead, $size) = @$style;
851 my $name = concise_op($op, $level, $treefmt);
852 if (not $op->flags & OPf_KIDS) {
856 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
857 push @lines, tree($kid, $level+1);
860 for ($i = $#lines; substr($lines[$i], 0, 1) eq " "; $i--) {
861 $lines[$i] = $space . $lines[$i];
864 $lines[$i] = $last . $lines[$i];
866 if (substr($lines[$i], 0, 1) eq " ") {
867 $lines[$i] = $nokid . $lines[$i];
869 $lines[$i] = $kid . $lines[$i];
872 $lines[$i] = $kids . $lines[$i];
874 $lines[0] = $single . $lines[0];
876 return("$name$lead" . shift @lines,
877 map(" " x (length($name)+$size) . $_, @lines));
880 # *** Warning: fragile kludge ahead ***
881 # Because the B::* modules run in the same interpreter as the code
882 # they're compiling, their presence tends to distort the view we have of
883 # the code we're looking at. In particular, perl gives sequence numbers
884 # to COPs. If the program we're looking at were run on its own, this
885 # would start at 1. Because all of B::Concise and all the modules it
886 # uses are compiled first, though, by the time we get to the user's
887 # program the sequence number is already pretty high, which could be
888 # distracting if you're trying to tell OPs apart. Therefore we'd like to
889 # subtract an offset from all the sequence numbers we display, to
890 # restore the simpler view of the world. The trick is to know what that
891 # offset will be, when we're still compiling B::Concise! If we
892 # hardcoded a value, it would have to change every time B::Concise or
893 # other modules we use do. To help a little, what we do here is compile
894 # a little code at the end of the module, and compute the base sequence
895 # number for the user's program as being a small offset later, so all we
896 # have to worry about are changes in the offset.
898 # [For 5.8.x and earlier perl is generating sequence numbers for all ops,
899 # and using them to reference labels]
902 # When you say "perl -MO=Concise -e '$a'", the output should look like:
904 # 4 <@> leave[t1] vKP/REFC ->(end)
906 #^ smallest OP sequence number should be 1
907 # 2 <;> nextstate(main 1 -e:1) v ->3
908 # ^ smallest COP sequence number should be 1
909 # - <1> ex-rv2sv vK/1 ->4
910 # 3 <$> gvsv(*a) s ->4
912 # If the second of the marked numbers there isn't 1, it means you need
913 # to update the corresponding magic number in the next line.
914 # Remember, this needs to stay the last things in the module.
916 # Why is this different for MacOS? Does it matter?
917 my $cop_seq_mnum = $^O eq 'MacOS' ? 12 : 11;
918 $cop_seq_base = svref_2object(eval 'sub{0;}')->START->cop_seq + $cop_seq_mnum;
926 B::Concise - Walk Perl syntax tree, printing concise info about ops
930 perl -MO=Concise[,OPTIONS] foo.pl
932 use B::Concise qw(set_style add_callback);
936 This compiler backend prints the internal OPs of a Perl program's syntax
937 tree in one of several space-efficient text formats suitable for debugging
938 the inner workings of perl or other compiler backends. It can print OPs in
939 the order they appear in the OP tree, in the order they will execute, or
940 in a text approximation to their tree structure, and the format of the
941 information displyed is customizable. Its function is similar to that of
942 perl's B<-Dx> debugging flag or the B<B::Terse> module, but it is more
943 sophisticated and flexible.
947 Here's an example of 2 outputs (aka 'renderings'), using the
948 -exec and -basic (i.e. default) formatting conventions on the same code
951 % perl -MO=Concise,-exec -e '$a = $b + 42'
953 2 <;> nextstate(main 1 -e:1) v
959 8 <@> leave[1 ref] vKP/REFC
961 Each line corresponds to an opcode. The opcode marked with '*' is used
962 in a few examples below.
964 The 1st column is the op's sequence number, starting at 1, and is
965 displayed in base 36 by default. This rendering is in -exec (i.e.
968 The symbol between angle brackets indicates the op's type, for
969 example; <2> is a BINOP, <@> a LISTOP, and <#> is a PADOP, which is
970 used in threaded perls. (see L</"OP class abbreviations">).
972 The opname, as in B<'add[t1]'>, which may be followed by op-specific
973 information in parentheses or brackets (ex B<'[t1]'>).
975 The op-flags (ex B<'sK/2'>) follow, and are described in (L</"OP flags
978 % perl -MO=Concise -e '$a = $b + 42'
979 8 <@> leave[1 ref] vKP/REFC ->(end)
981 2 <;> nextstate(main 1 -e:1) v ->3
982 7 <2> sassign vKS/2 ->8
983 * 5 <2> add[t1] sK/2 ->6
984 - <1> ex-rv2sv sK/1 ->4
986 4 <$> const(IV 42) s ->5
987 - <1> ex-rv2sv sKRM*/1 ->7
990 The default rendering is top-down, so they're not in execution order.
991 This form reflects the way the stack is used to parse and evaluate
992 expressions; the add operates on the two terms below it in the tree.
994 Nullops appear as C<ex-opname>, where I<opname> is an op that has been
995 optimized away by perl. They're displayed with a sequence-number of
996 '-', because they are not executed (they don't appear in previous
997 example), they're printed here because they reflect the parse.
999 The arrow points to the sequence number of the next op; they're not
1000 displayed in -exec mode, for obvious reasons.
1002 Note that because this rendering was done on a non-threaded perl, the
1003 PADOPs in the previous examples are now SVOPs, and some (but not all)
1004 of the square brackets have been replaced by round ones. This is a
1005 subtle feature to provide some visual distinction between renderings
1006 on threaded and un-threaded perls.
1011 Arguments that don't start with a hyphen are taken to be the names of
1012 subroutines to print the OPs of; if no such functions are specified,
1013 the main body of the program (outside any subroutines, and not
1014 including use'd or require'd files) is rendered. Passing C<BEGIN>,
1015 C<CHECK>, C<INIT>, or C<END> will cause all of the corresponding
1016 special blocks to be printed.
1018 Options affect how things are rendered (ie printed). They're presented
1019 here by their visual effect, 1st being strongest. They're grouped
1020 according to how they interrelate; within each group the options are
1021 mutually exclusive (unless otherwise stated).
1023 =head2 Options for Opcode Ordering
1025 These options control the 'vertical display' of opcodes. The display
1026 'order' is also called 'mode' elsewhere in this document.
1032 Print OPs in the order they appear in the OP tree (a preorder
1033 traversal, starting at the root). The indentation of each OP shows its
1034 level in the tree, and the '->' at the end of the line indicates the
1035 next opcode in execution order. This mode is the default, so the flag
1036 is included simply for completeness.
1040 Print OPs in the order they would normally execute (for the majority
1041 of constructs this is a postorder traversal of the tree, ending at the
1042 root). In most cases the OP that usually follows a given OP will
1043 appear directly below it; alternate paths are shown by indentation. In
1044 cases like loops when control jumps out of a linear path, a 'goto'
1049 Print OPs in a text approximation of a tree, with the root of the tree
1050 at the left and 'left-to-right' order of children transformed into
1051 'top-to-bottom'. Because this mode grows both to the right and down,
1052 it isn't suitable for large programs (unless you have a very wide
1057 =head2 Options for Line-Style
1059 These options select the line-style (or just style) used to render
1060 each opcode, and dictates what info is actually printed into each line.
1066 Use the author's favorite set of formatting conventions. This is the
1071 Use formatting conventions that emulate the output of B<B::Terse>. The
1072 basic mode is almost indistinguishable from the real B<B::Terse>, and the
1073 exec mode looks very similar, but is in a more logical order and lacks
1074 curly brackets. B<B::Terse> doesn't have a tree mode, so the tree mode
1075 is only vaguely reminiscent of B<B::Terse>.
1079 Use formatting conventions in which the name of each OP, rather than being
1080 written out in full, is represented by a one- or two-character abbreviation.
1081 This is mainly a joke.
1085 Use formatting conventions reminiscent of B<B::Debug>; these aren't
1086 very concise at all.
1090 Use formatting conventions read from the environment variables
1091 C<B_CONCISE_FORMAT>, C<B_CONCISE_GOTO_FORMAT>, and C<B_CONCISE_TREE_FORMAT>.
1095 =head2 Options for tree-specific formatting
1101 Use a tree format in which the minimum amount of space is used for the
1102 lines connecting nodes (one character in most cases). This squeezes out
1103 a few precious columns of screen real estate.
1107 Use a tree format that uses longer edges to separate OP nodes. This format
1108 tends to look better than the compact one, especially in ASCII, and is
1113 Use tree connecting characters drawn from the VT100 line-drawing set.
1114 This looks better if your terminal supports it.
1118 Draw the tree with standard ASCII characters like C<+> and C<|>. These don't
1119 look as clean as the VT100 characters, but they'll work with almost any
1120 terminal (or the horizontal scrolling mode of less(1)) and are suitable
1121 for text documentation or email. This is the default.
1125 These are pairwise exclusive, i.e. compact or loose, vt or ascii.
1127 =head2 Options controlling sequence numbering
1133 Print OP sequence numbers in base I<n>. If I<n> is greater than 10, the
1134 digit for 11 will be 'a', and so on. If I<n> is greater than 36, the digit
1135 for 37 will be 'A', and so on until 62. Values greater than 62 are not
1136 currently supported. The default is 36.
1140 Print sequence numbers with the most significant digit first. This is the
1141 usual convention for Arabic numerals, and the default.
1143 =item B<-littleendian>
1145 Print seqence numbers with the least significant digit first. This is
1146 obviously mutually exclusive with bigendian.
1150 =head2 Other options
1152 These are pairwise exclusive.
1158 Include the main program in the output, even if subroutines were also
1159 specified. This rendering is normally suppressed when a subroutine
1160 name or reference is given.
1164 This restores the default behavior after you've changed it with '-main'
1165 (it's not normally needed). If no subroutine name/ref is given, main is
1166 rendered, regardless of this flag.
1170 Renderings usually include a banner line identifying the function name
1171 or stringified subref. This suppresses the printing of the banner.
1173 TBC: Remove the stringified coderef; while it provides a 'cookie' for
1174 each function rendered, the cookies used should be 1,2,3.. not a
1175 random hex-address. It also complicates string comparison of two
1180 restores default banner behavior.
1182 =item B<-banneris> => subref
1184 TBC: a hookpoint (and an option to set it) for a user-supplied
1185 function to produce a banner appropriate for users needs. It's not
1186 ideal, because the rendering-state variables, which are a natural
1187 candidate for use in concise.t, are unavailable to the user.
1191 =head2 Option Stickiness
1193 If you invoke Concise more than once in a program, you should know that
1194 the options are 'sticky'. This means that the options you provide in
1195 the first call will be remembered for the 2nd call, unless you
1196 re-specify or change them.
1198 =head1 ABBREVIATIONS
1200 The concise style uses symbols to convey maximum info with minimal
1201 clutter (like hex addresses). With just a little practice, you can
1202 start to see the flowers, not just the branches, in the trees.
1204 =head2 OP class abbreviations
1206 These symbols appear before the op-name, and indicate the
1207 B:: namespace that represents the ops in your Perl code.
1209 0 OP (aka BASEOP) An OP with no children
1210 1 UNOP An OP with one child
1211 2 BINOP An OP with two children
1212 | LOGOP A control branch OP
1213 @ LISTOP An OP that could have lots of children
1214 / PMOP An OP with a regular expression
1215 $ SVOP An OP with an SV
1216 " PVOP An OP with a string
1217 { LOOP An OP that holds pointers for a loop
1218 ; COP An OP that marks the start of a statement
1219 # PADOP An OP with a GV on the pad
1221 =head2 OP flags abbreviations
1223 OP flags are either public or private. The public flags alter the
1224 behavior of each opcode in consistent ways, and are represented by 0
1225 or more single characters.
1227 v OPf_WANT_VOID Want nothing (void context)
1228 s OPf_WANT_SCALAR Want single value (scalar context)
1229 l OPf_WANT_LIST Want list of any length (list context)
1231 K OPf_KIDS There is a firstborn child.
1232 P OPf_PARENS This operator was parenthesized.
1233 (Or block needs explicit scope entry.)
1234 R OPf_REF Certified reference.
1235 (Return container, not containee).
1236 M OPf_MOD Will modify (lvalue).
1237 S OPf_STACKED Some arg is arriving on the stack.
1238 * OPf_SPECIAL Do something weird for this op (see op.h)
1240 Private flags, if any are set for an opcode, are displayed after a '/'
1242 8 <@> leave[1 ref] vKP/REFC ->(end)
1243 7 <2> sassign vKS/2 ->8
1245 They're opcode specific, and occur less often than the public ones, so
1246 they're represented by short mnemonics instead of single-chars; see
1247 L<op.h> for gory details, or try this quick 2-liner:
1249 $> perl -MB::Concise -de 1
1250 DB<1> |x \%B::Concise::priv
1252 =head1 FORMATTING SPECIFICATIONS
1254 For each line-style ('concise', 'terse', 'linenoise', etc.) there are
1255 3 format-specs which control how OPs are rendered.
1257 The first is the 'default' format, which is used in both basic and exec
1258 modes to print all opcodes. The 2nd, goto-format, is used in exec
1259 mode when branches are encountered. They're not real opcodes, and are
1260 inserted to look like a closing curly brace. The tree-format is tree
1263 When a line is rendered, the correct format-spec is copied and scanned
1264 for the following items; data is substituted in, and other
1265 manipulations like basic indenting are done, for each opcode rendered.
1267 There are 3 kinds of items that may be populated; special patterns,
1268 #vars, and literal text, which is copied verbatim. (Yes, it's a set
1271 =head2 Special Patterns
1273 These items are the primitives used to perform indenting, and to
1274 select text from amongst alternatives.
1278 =item B<(x(>I<exec_text>B<;>I<basic_text>B<)x)>
1280 Generates I<exec_text> in exec mode, or I<basic_text> in basic mode.
1282 =item B<(*(>I<text>B<)*)>
1284 Generates one copy of I<text> for each indentation level.
1286 =item B<(*(>I<text1>B<;>I<text2>B<)*)>
1288 Generates one fewer copies of I<text1> than the indentation level, followed
1289 by one copy of I<text2> if the indentation level is more than 0.
1291 =item B<(?(>I<text1>B<#>I<var>I<Text2>B<)?)>
1293 If the value of I<var> is true (not empty or zero), generates the
1294 value of I<var> surrounded by I<text1> and I<Text2>, otherwise
1299 Any number of tildes and surrounding whitespace will be collapsed to
1306 These #vars represent opcode properties that you may want as part of
1307 your rendering. The '#' is intended as a private sigil; a #var's
1308 value is interpolated into the style-line, much like "read $this".
1310 These vars take 3 forms:
1316 A property named 'var' is assumed to exist for the opcodes, and is
1317 interpolated into the rendering.
1319 =item B<#>I<var>I<N>
1321 Generates the value of I<var>, left justified to fill I<N> spaces.
1322 Note that this means while you can have properties 'foo' and 'foo2',
1323 you cannot render 'foo2', but you could with 'foo2a'. You would be
1324 wise not to rely on this behavior going forward ;-)
1328 This ucfirst form of #var generates a tag-value form of itself for
1329 display; it converts '#Var' into a 'Var => #var' style, which is then
1330 handled as described above. (Imp-note: #Vars cannot be used for
1331 conditional-fills, because the => #var transform is done after the check
1336 The following variables are 'defined' by B::Concise; when they are
1337 used in a style, their respective values are plugged into the
1338 rendering of each opcode.
1340 Only some of these are used by the standard styles, the others are
1341 provided for you to delve into optree mechanics, should you wish to
1342 add a new style (see L</add_style> below) that uses them. You can
1343 also add new ones using L<add_callback>.
1349 The address of the OP, in hexadecimal.
1353 The OP-specific information of the OP (such as the SV for an SVOP, the
1354 non-local exit pointers for a LOOP, etc.) enclosed in parentheses.
1358 The B-determined class of the OP, in all caps.
1362 A single symbol abbreviating the class of the OP.
1366 The label of the statement or block the OP is the start of, if any.
1370 The name of the OP, or 'ex-foo' if the OP is a null that used to be a foo.
1374 The target of the OP, or nothing for a nulled OP.
1378 The address of the OP's first child, in hexadecimal.
1382 The OP's flags, abbreviated as a series of symbols.
1386 The numeric value of the OP's flags.
1390 The sequence number of the OP, or a hyphen if it doesn't have one.
1394 'NEXT', 'LAST', or 'REDO' if the OP is a target of one of those in exec
1395 mode, or empty otherwise.
1399 The address of the OP's last child, in hexadecimal.
1407 The OP's name, in all caps.
1411 The sequence number of the OP's next OP.
1415 The address of the OP's next OP, in hexadecimal.
1419 A one- or two-character abbreviation for the OP's name.
1423 The OP's private flags, rendered with abbreviated names if possible.
1427 The numeric value of the OP's private flags.
1431 The sequence number of the OP. Note that this is a sequence number
1432 generated by B::Concise.
1436 5.8.x and earlier only. 5.9 and later do not provide this.
1438 The real sequence number of the OP, as a regular number and not adjusted
1439 to be relative to the start of the real program. (This will generally be
1440 a fairly large number because all of B<B::Concise> is compiled before
1445 Whether or not the op has been optimised by the peephole optimiser.
1447 Only available in 5.9 and later.
1451 Whether or not the op is statically defined. This flag is used by the
1452 B::C compiler backend and indicates that the op should not be freed.
1454 Only available in 5.9 and later.
1458 The address of the OP's next youngest sibling, in hexadecimal.
1462 The address of the OP's SV, if it has an SV, in hexadecimal.
1466 The class of the OP's SV, if it has one, in all caps (e.g., 'IV').
1470 The value of the OP's SV, if it has one, in a short human-readable format.
1474 The numeric value of the OP's targ.
1478 The name of the variable the OP's targ refers to, if any, otherwise the
1479 letter t followed by the OP's targ in decimal.
1481 =item B<#targarglife>
1483 Same as B<#targarg>, but followed by the COP sequence numbers that delimit
1484 the variable's lifetime (or 'end' for a variable in an open scope) for a
1489 The numeric value of the OP's type, in decimal.
1493 =head1 Using B::Concise outside of the O framework
1495 The common (and original) usage of B::Concise was for command-line
1496 renderings of simple code, as given in EXAMPLE. But you can also use
1497 B<B::Concise> from your code, and call compile() directly, and
1498 repeatedly. By doing so, you can avoid the compile-time only
1499 operation of O.pm, and even use the debugger to step through
1500 B::Concise::compile() itself.
1502 Once you're doing this, you may alter Concise output by adding new
1503 rendering styles, and by optionally adding callback routines which
1504 populate new variables, if such were referenced from those (just
1507 =head2 Example: Altering Concise Renderings
1509 use B::Concise qw(set_style add_callback);
1510 add_style($yourStyleName => $defaultfmt, $gotofmt, $treefmt);
1513 my ($h, $op, $format, $level, $stylename) = @_;
1514 $h->{variable} = some_func($op);
1516 $walker = B::Concise::compile(@options,@subnames,@subrefs);
1521 B<set_style> accepts 3 arguments, and updates the three format-specs
1522 comprising a line-style (basic-exec, goto, tree). It has one minor
1523 drawback though; it doesn't register the style under a new name. This
1524 can become an issue if you render more than once and switch styles.
1525 Thus you may prefer to use add_style() and/or set_style_standard()
1528 =head2 set_style_standard($name)
1530 This restores one of the standard line-styles: C<terse>, C<concise>,
1531 C<linenoise>, C<debug>, C<env>, into effect. It also accepts style
1532 names previously defined with add_style().
1536 This subroutine accepts a new style name and three style arguments as
1537 above, and creates, registers, and selects the newly named style. It is
1538 an error to re-add a style; call set_style_standard() to switch between
1541 =head2 add_callback()
1543 If your newly minted styles refer to any new #variables, you'll need
1544 to define a callback subroutine that will populate (or modify) those
1545 variables. They are then available for use in the style you've
1548 The callbacks are called for each opcode visited by Concise, in the
1549 same order as they are added. Each subroutine is passed five
1552 1. A hashref, containing the variable names and values which are
1553 populated into the report-line for the op
1554 2. the op, as a B<B::OP> object
1555 3. a reference to the format string
1556 4. the formatting (indent) level
1557 5. the selected stylename
1559 To define your own variables, simply add them to the hash, or change
1560 existing values if you need to. The level and format are passed in as
1561 references to scalars, but it is unlikely that they will need to be
1562 changed or even used.
1564 =head2 Running B::Concise::compile()
1566 B<compile> accepts options as described above in L</OPTIONS>, and
1567 arguments, which are either coderefs, or subroutine names.
1569 It constructs and returns a $treewalker coderef, which when invoked,
1570 traverses, or walks, and renders the optrees of the given arguments to
1571 STDOUT. You can reuse this, and can change the rendering style used
1572 each time; thereafter the coderef renders in the new style.
1574 B<walk_output> lets you change the print destination from STDOUT to
1575 another open filehandle, or into a string passed as a ref (unless
1576 you've built perl with -Uuseperlio).
1578 my $walker = B::Concise::compile('-terse','aFuncName', \&aSubRef); # 1
1579 walk_output(\my $buf);
1580 $walker->(); # 1 renders -terse
1581 set_style_standard('concise'); # 2
1582 $walker->(); # 2 renders -concise
1583 $walker->(@new); # 3 renders whatever
1584 print "3 different renderings: terse, concise, and @new: $buf\n";
1586 When $walker is called, it traverses the subroutines supplied when it
1587 was created, and renders them using the current style. You can change
1588 the style afterwards in several different ways:
1590 1. call C<compile>, altering style or mode/order
1591 2. call C<set_style_standard>
1592 3. call $walker, passing @new options
1594 Passing new options to the $walker is the easiest way to change
1595 amongst any pre-defined styles (the ones you add are automatically
1596 recognized as options), and is the only way to alter rendering order
1597 without calling compile again. Note however that rendering state is
1598 still shared amongst multiple $walker objects, so they must still be
1599 used in a coordinated manner.
1601 =head2 B::Concise::reset_sequence()
1603 This function (not exported) lets you reset the sequence numbers (note
1604 that they're numbered arbitrarily, their goal being to be human
1605 readable). Its purpose is mostly to support testing, i.e. to compare
1606 the concise output from two identical anonymous subroutines (but
1607 different instances). Without the reset, B::Concise, seeing that
1608 they're separate optrees, generates different sequence numbers in
1613 All detected errors, (invalid arguments, internal errors, etc.) are
1614 resolved with a die($message). Use an eval if you wish to catch these
1615 errors and continue processing.
1617 In particular, B<compile> will die if you've asked for a non-existent
1618 function-name, a non-existent coderef, or a non-CODE reference.
1622 Stephen McCamant, E<lt>smcc@CSUA.Berkeley.EDUE<gt>.