2 # Copyright (C) 2000, 2001 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.
11 our $VERSION = "0.52";
12 our @ISA = qw(Exporter);
13 our @EXPORT_OK = qw(set_style add_callback);
15 use B qw(class ppname main_start main_root main_cv cstring svref_2object
16 SVf_IOK SVf_NOK SVf_POK OPf_KIDS);
20 ["(?(#label =>\n)?)(*( )*)#class (#addr) #name (?([#targ])?) "
21 . "#svclass~(?((#svaddr))?)~#svval~(?(label \"#coplabel\")?)\n",
22 "(*( )*)goto #class (#addr)\n",
25 ["#hyphseq2 (*( (x( ;)x))*)<#classsym> "
26 . "#exname#arg(?([#targarglife])?)~#flags(?(/#private)?)(x(;~->#next)x)\n",
27 " (*( )*) goto #seq\n",
28 "(?(<#seq>)?)#exname#arg(?([#targarglife])?)"],
30 ["(x(;(*( )*))x)#noise#arg(?([#targarg])?)(x( ;\n)x)",
32 "(?(#seq)?)#noise#arg(?([#targarg])?)"],
34 ["#class (#addr)\n\top_next\t\t#nextaddr\n\top_sibling\t#sibaddr\n\t"
35 . "op_ppaddr\tPL_ppaddr[OP_#NAME]\n\top_type\t\t#typenum\n\top_seq\t\t"
36 . "#seqnum\n\top_flags\t#flagval\n\top_private\t#privval\n"
37 . "(?(\top_first\t#firstaddr\n)?)(?(\top_last\t\t#lastaddr\n)?)"
38 . "(?(\top_sv\t\t#svaddr\n)?)",
41 "env" => [$ENV{B_CONCISE_FORMAT}, $ENV{B_CONCISE_GOTO_FORMAT},
42 $ENV{B_CONCISE_TREE_FORMAT}],
45 my($format, $gotofmt, $treefmt);
47 my($seq_base, $cop_seq_base);
51 ($format, $gotofmt, $treefmt) = @_;
59 my ($order, $cvref) = @_;
60 my $cv = svref_2object($cvref);
62 if ($order eq "exec") {
63 walk_exec($cv->START);
64 } elsif ($order eq "basic") {
65 walk_topdown($cv->ROOT, sub { $_[0]->concise($_[1]) }, 0);
67 print tree($cv->ROOT, 0)
71 my $start_sym = "\e(0"; # "\cN" sometimes also works
72 my $end_sym = "\e(B"; # "\cO" respectively
74 my @tree_decorations =
75 ([" ", "--", "+-", "|-", "| ", "`-", "-", 1],
76 [" ", "-", "+", "+", "|", "`", "", 0],
77 [" ", map("$start_sym$_$end_sym", "qq", "wq", "tq", "x ", "mq", "q"), 1],
78 [" ", map("$start_sym$_$end_sym", "q", "w", "t", "x", "m"), "", 0],
87 set_style(@{$style{concise}});
90 my @options = grep(/^-/, @_);
91 my @args = grep(!/^-/, @_);
93 for my $o (@options) {
96 } elsif ($o eq "-exec") {
98 } elsif ($o eq "-tree") {
100 } elsif ($o eq "-compact") {
102 } elsif ($o eq "-loose") {
104 } elsif ($o eq "-vt") {
106 } elsif ($o eq "-ascii") {
108 } elsif ($o eq "-main") {
110 } elsif ($o =~ /^-base(\d+)$/) {
112 } elsif ($o eq "-bigendian") {
114 } elsif ($o eq "-littleendian") {
116 } elsif (exists $style{substr($o, 1)}) {
117 set_style(@{$style{substr($o, 1)}});
119 warn "Option $o unrecognized";
124 for my $objname (@args) {
125 $objname = "main::" . $objname unless $objname =~ /::/;
126 eval "concise_cv(\$order, \\&$objname)";
127 die "concise_cv($order, \\&$objname) failed: $@" if $@;
131 if (!@args or $do_main) {
132 if ($order eq "exec") {
133 return sub { return if class(main_start) eq "NULL";
135 walk_exec(main_start) }
136 } elsif ($order eq "tree") {
137 return sub { return if class(main_root) eq "NULL";
139 print tree(main_root, 0) }
140 } elsif ($order eq "basic") {
141 return sub { return if class(main_root) eq "NULL";
143 walk_topdown(main_root,
144 sub { $_[0]->concise($_[1]) }, 0); }
152 my %opclass = ('OP' => "0", 'UNOP' => "1", 'BINOP' => "2", 'LOGOP' => "|",
153 'LISTOP' => "@", 'PMOP' => "/", 'SVOP' => "\$", 'GVOP' => "*",
154 'PVOP' => '"', 'LOOP' => "{", 'COP' => ";", 'PADOP' => "#");
156 no warnings 'qw'; # "Possible attempt to put comments..."
158 qw'# () sc ( @? 1 $* gv *{ m$ m@ m% m? p/ *$ $ $# & a& pt \\ s\\ rf bl
159 ` *? <> ?? ?/ r/ c/ // qr s/ /c y/ = @= C sC Cp sp df un BM po +1 +I
160 -1 -I 1+ I+ 1- I- ** * i* / i/ %$ i% x + i+ - i- . " << >> < i<
161 > i> <= i, >= i. == i= != i! <? i? s< s> s, s. s= s! s? b& b^ b| -0 -i
162 ! ~ a2 si cs rd sr e^ lg sq in %x %o ab le ss ve ix ri sf FL od ch cy
163 uf lf uc lc qm @ [f [ @[ eh vl ky dl ex % ${ @{ uk pk st jn ) )[ a@
164 a% sl +] -] [- [+ so rv GS GW MS MW .. f. .f && || ^^ ?: &= |= -> s{ s}
165 v} ca wa di rs ;; ; ;d }{ { } {} f{ it {l l} rt }l }n }r dm }g }e ^o
166 ^c ^| ^# um bm t~ u~ ~d DB db ^s se ^g ^r {w }w pf pr ^O ^K ^R ^W ^d ^v
167 ^e ^t ^k t. fc ic fl .s .p .b .c .l .a .h g1 s1 g2 s2 ?. l? -R -W -X -r
168 -w -x -e -o -O -z -s -M -A -C -S -c -b -f -d -p -l -u -g -k -t -T -B cd
169 co cr u. cm ut r. l@ s@ r@ mD uD oD rD tD sD wD cD f$ w$ p$ sh e$ k$ g3
170 g4 s4 g5 s5 T@ C@ L@ G@ A@ S@ Hg Hc Hr Hw Mg Mc Ms Mr Sg Sc So rq do {e
171 e} {t t} g6 G6 6e g7 G7 7e g8 G8 8e g9 G9 9e 6s 7s 8s 9s 6E 7E 8E 9E Pn
172 Pu GP SP EP Gn Gg GG SG EG g0 c$ lk t$ ;s n>';
174 my $chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
179 push @v, "v" if ($x & 3) == 1;
180 push @v, "s" if ($x & 3) == 2;
181 push @v, "l" if ($x & 3) == 3;
182 push @v, "K" if $x & 4;
183 push @v, "P" if $x & 8;
184 push @v, "R" if $x & 16;
185 push @v, "M" if $x & 32;
186 push @v, "S" if $x & 64;
187 push @v, "*" if $x & 128;
193 return "-" . base_n(-$x) if $x < 0;
195 do { $str .= substr($chars, $x % $base, 1) } while $x = int($x / $base);
196 $str = reverse $str if $big_endian;
200 sub seq { return $_[0]->seq ? base_n($_[0]->seq - $seq_base) : "-" }
203 my($op, $sub, $level) = @_;
205 if ($op->flags & OPf_KIDS) {
206 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
207 walk_topdown($kid, $sub, $level + 1);
210 if (class($op) eq "PMOP" and $ {$op->pmreplroot}
211 and $op->pmreplroot->isa("B::OP")) {
212 walk_topdown($op->pmreplroot, $sub, $level + 1);
217 my($ar, $level) = @_;
219 if (ref($l) eq "ARRAY") {
220 walklines($l, $level + 1);
228 my($top, $level) = @_;
231 my @todo = ([$top, \@lines]);
232 while (@todo and my($op, $targ) = @{shift @todo}) {
233 for (; $$op; $op = $op->next) {
234 last if $opsseen{$$op}++;
236 my $name = $op->name;
238 =~ /^(or|and|(map|grep)while|entertry|range|cond_expr)$/) {
241 push @todo, [$op->other, $ar];
242 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
245 push @todo, [$op->pmreplstart, $ar];
246 } elsif ($name =~ /^enter(loop|iter)$/) {
247 $labels{$op->nextop->seq} = "NEXT";
248 $labels{$op->lastop->seq} = "LAST";
249 $labels{$op->redoop->seq} = "REDO";
253 walklines(\@lines, 0);
257 my($hr, $fmt, $level) = @_;
259 $text =~ s/\(\?\(([^\#]*?)\#(\w+)([^\#]*?)\)\?\)/
260 $hr->{$2} ? $1.$hr->{$2}.$3 : ""/eg;
261 $text =~ s/\(x\((.*?);(.*?)\)x\)/$order eq "exec" ? $1 : $2/egs;
262 $text =~ s/\(\*\(([^;]*?)\)\*\)/$1 x $level/egs;
263 $text =~ s/\(\*\((.*?);(.*?)\)\*\)/$1 x ($level - 1) . $2 x ($level>0)/egs;
264 $text =~ s/#([a-zA-Z]+)(\d+)/sprintf("%-$2s", $hr->{$1})/eg;
265 $text =~ s/#([a-zA-Z]+)/$hr->{$1}/eg;
266 $text =~ s/[ \t]*~+[ \t]*/ /g;
271 $priv{$_}{128} = "LVINTRO"
272 for ("pos", "substr", "vec", "threadsv", "gvsv", "rv2sv", "rv2hv", "rv2gv",
273 "rv2av", "rv2arylen", "aelem", "helem", "aslice", "hslice", "padsv",
275 $priv{$_}{64} = "REFC" for ("leave", "leavesub", "leavesublv", "leavewrite");
276 $priv{"aassign"}{64} = "COMMON";
277 $priv{"sassign"}{64} = "BKWARD";
278 $priv{$_}{64} = "RTIME" for ("match", "subst", "substcont");
279 @{$priv{"trans"}}{1,2,4,8,16,64} = ("<UTF", ">UTF", "IDENT", "SQUASH", "DEL",
281 $priv{"repeat"}{64} = "DOLIST";
282 $priv{"leaveloop"}{64} = "CONT";
283 @{$priv{$_}}{32,64,96} = ("DREFAV", "DREFHV", "DREFSV")
284 for ("entersub", map("rv2${_}v", "a", "s", "h", "g"), "aelem", "helem");
285 $priv{"entersub"}{16} = "DBG";
286 $priv{"entersub"}{32} = "TARG";
287 @{$priv{$_}}{4,8,128} = ("INARGS","AMPER","NO()") for ("entersub", "rv2cv");
288 $priv{"gv"}{32} = "EARLYCV";
289 $priv{"aelem"}{16} = $priv{"helem"}{16} = "LVDEFER";
290 $priv{$_}{16} = "OURINTR" for ("gvsv", "rv2sv", "rv2av", "rv2hv", "r2gv");
291 $priv{$_}{16} = "TARGMY"
292 for (map(($_,"s$_"),"chop", "chomp"),
293 map(($_,"i_$_"), "postinc", "postdec", "multiply", "divide", "modulo",
294 "add", "subtract", "negate"), "pow", "concat", "stringify",
295 "left_shift", "right_shift", "bit_and", "bit_xor", "bit_or",
296 "complement", "atan2", "sin", "cos", "rand", "exp", "log", "sqrt",
297 "int", "hex", "oct", "abs", "length", "index", "rindex", "sprintf",
298 "ord", "chr", "crypt", "quotemeta", "join", "push", "unshift", "flock",
299 "chdir", "chown", "chroot", "unlink", "chmod", "utime", "rename",
300 "link", "symlink", "mkdir", "rmdir", "wait", "waitpid", "system",
301 "exec", "kill", "getppid", "getpgrp", "setpgrp", "getpriority",
302 "setpriority", "time", "sleep");
303 @{$priv{"const"}}{8,16,32,64,128} = ("STRICT","ENTERED", '$[', "BARE", "WARN");
304 $priv{"flip"}{64} = $priv{"flop"}{64} = "LINENUM";
305 $priv{"list"}{64} = "GUESSED";
306 $priv{"delete"}{64} = "SLICE";
307 $priv{"exists"}{64} = "SUB";
308 $priv{$_}{64} = "LOCALE"
309 for ("sort", "prtf", "sprintf", "slt", "sle", "seq", "sne", "sgt", "sge",
310 "scmp", "lc", "uc", "lcfirst", "ucfirst");
311 @{$priv{"sort"}}{1,2,4} = ("NUM", "INT", "REV");
312 $priv{"threadsv"}{64} = "SVREFd";
313 $priv{$_}{16} = "INBIN" for ("open", "backtick");
314 $priv{$_}{32} = "INCR" for ("open", "backtick");
315 $priv{$_}{64} = "OUTBIN" for ("open", "backtick");
316 $priv{$_}{128} = "OUTCR" for ("open", "backtick");
317 $priv{"exit"}{128} = "VMS";
322 for my $flag (128, 96, 64, 32, 16, 8, 4, 2, 1) {
323 if ($priv{$name}{$flag} and $x & $flag and $x >= $flag) {
325 push @s, $priv{$name}{$flag};
329 return join(",", @s);
333 my ($op, $level, $format) = @_;
335 $h{exname} = $h{name} = $op->name;
336 $h{NAME} = uc $h{name};
337 $h{class} = class($op);
338 $h{extarg} = $h{targ} = $op->targ;
339 $h{extarg} = "" unless $h{extarg};
340 if ($h{name} eq "null" and $h{targ}) {
341 $h{exname} = "ex-" . substr(ppname($h{targ}), 3);
344 my $padname = (($curcv->PADLIST->ARRAY)[0]->ARRAY)[$h{targ}];
345 if (defined $padname and class($padname) ne "SPECIAL") {
346 $h{targarg} = $padname->PVX;
347 my $intro = $padname->NVX - $cop_seq_base;
348 my $finish = int($padname->IVX) - $cop_seq_base;
349 $finish = "end" if $finish == 999999999 - $cop_seq_base;
350 $h{targarglife} = "$h{targarg}:$intro,$finish";
352 $h{targarglife} = $h{targarg} = "t" . $h{targ};
356 $h{svclass} = $h{svaddr} = $h{svval} = "";
357 if ($h{class} eq "PMOP") {
358 my $precomp = $op->precomp;
359 if (defined $precomp) {
360 # Escape literal control sequences
362 s/\t/\\t/g; s/\n/\\n/g; s/\r/\\r/g;
363 # How can we do the below portably?
364 #s/([\0-\037\177-\377])/"\\".sprintf("%03o", ord($1))/eg;
366 $precomp = "/$precomp/";
368 else { $precomp = ""; }
369 my $pmreplroot = $op->pmreplroot;
371 if ($$pmreplroot && $pmreplroot->isa("B::GV")) {
372 # with C<@stash_array = split(/pat/, str);>,
373 # *stash_array is stored in pmreplroot.
374 $h{arg} = "($precomp => \@" . $pmreplroot->NAME . ")";
375 } elsif ($ {$op->pmreplstart}) {
377 $pmreplstart = "replstart->" . seq($op->pmreplstart);
378 $h{arg} = "(" . join(" ", $precomp, $pmreplstart) . ")";
380 $h{arg} = "($precomp)";
382 } elsif ($h{class} eq "PVOP" and $h{name} ne "trans") {
383 $h{arg} = '("' . $op->pv . '")';
384 $h{svval} = '"' . $op->pv . '"';
385 } elsif ($h{class} eq "COP") {
386 my $label = $op->label;
387 $h{coplabel} = $label;
388 $label = $label ? "$label: " : "";
391 $loc .= ":" . $op->line;
392 my($stash, $cseq) = ($op->stash->NAME, $op->cop_seq - $cop_seq_base);
393 my $arybase = $op->arybase;
394 $arybase = $arybase ? ' $[=' . $arybase : "";
395 $h{arg} = "($label$stash $cseq $loc$arybase)";
396 } elsif ($h{class} eq "LOOP") {
397 $h{arg} = "(next->" . seq($op->nextop) . " last->" . seq($op->lastop)
398 . " redo->" . seq($op->redoop) . ")";
399 } elsif ($h{class} eq "LOGOP") {
401 $h{arg} = "(other->" . seq($op->other) . ")";
402 } elsif ($h{class} eq "SVOP") {
404 $h{svclass} = class($sv);
405 $h{svaddr} = sprintf("%#x", $$sv);
406 if ($h{svclass} eq "GV") {
408 my $stash = $gv->STASH->NAME;
409 if ($stash eq "main") {
412 $stash = $stash . "::";
414 $h{arg} = "(*$stash" . $gv->SAFENAME . ")";
415 $h{svval} = "*$stash" . $gv->SAFENAME;
417 while (class($sv) eq "RV") {
421 if (class($sv) eq "SPECIAL") {
422 $h{svval} = ["Null", "sv_undef", "sv_yes", "sv_no"]->[$$sv];
423 } elsif ($sv->FLAGS & SVf_NOK) {
425 } elsif ($sv->FLAGS & SVf_IOK) {
427 } elsif ($sv->FLAGS & SVf_POK) {
428 $h{svval} = cstring($sv->PV);
430 $h{arg} = "($h{svclass} $h{svval})";
433 $h{seq} = $h{hyphseq} = seq($op);
434 $h{seq} = "" if $h{seq} eq "-";
435 $h{seqnum} = $op->seq;
436 $h{next} = $op->next;
437 $h{next} = (class($h{next}) eq "NULL") ? "(end)" : seq($h{next});
438 $h{nextaddr} = sprintf("%#x", $ {$op->next});
439 $h{sibaddr} = sprintf("%#x", $ {$op->sibling});
440 $h{firstaddr} = sprintf("%#x", $ {$op->first}) if $op->can("first");
441 $h{lastaddr} = sprintf("%#x", $ {$op->last}) if $op->can("last");
443 $h{classsym} = $opclass{$h{class}};
444 $h{flagval} = $op->flags;
445 $h{flags} = op_flags($op->flags);
446 $h{privval} = $op->private;
447 $h{private} = private_flags($h{name}, $op->private);
448 $h{addr} = sprintf("%#x", $$op);
449 $h{label} = $labels{$op->seq};
450 $h{typenum} = $op->type;
451 $h{noise} = $linenoise[$op->type];
452 $_->(\%h, $op, \$format, \$level) for @callbacks;
453 return fmt_line(\%h, $format, $level);
457 my($op, $level) = @_;
458 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
459 my $h = {"seq" => seq($lastnext), "class" => class($lastnext),
460 "addr" => sprintf("%#x", $$lastnext)};
461 print fmt_line($h, $gotofmt, $level+1);
463 $lastnext = $op->next;
464 print concise_op($op, $level, $format);
470 my $style = $tree_decorations[$tree_style];
471 my($space, $single, $kids, $kid, $nokid, $last, $lead, $size) = @$style;
472 my $name = concise_op($op, $level, $treefmt);
473 if (not $op->flags & OPf_KIDS) {
477 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
478 push @lines, tree($kid, $level+1);
481 for ($i = $#lines; substr($lines[$i], 0, 1) eq " "; $i--) {
482 $lines[$i] = $space . $lines[$i];
485 $lines[$i] = $last . $lines[$i];
487 if (substr($lines[$i], 0, 1) eq " ") {
488 $lines[$i] = $nokid . $lines[$i];
490 $lines[$i] = $kid . $lines[$i];
493 $lines[$i] = $kids . $lines[$i];
495 $lines[0] = $single . $lines[0];
497 return("$name$lead" . shift @lines,
498 map(" " x (length($name)+$size) . $_, @lines));
501 # *** Warning: fragile kludge ahead ***
502 # Because the B::* modules run in the same interpreter as the code
503 # they're compiling, their presence tends to distort the view we have
504 # of the code we're looking at. In particular, perl gives sequence
505 # numbers to both OPs in general and COPs in particular. If the
506 # program we're looking at were run on its own, these numbers would
507 # start at 1. Because all of B::Concise and all the modules it uses
508 # are compiled first, though, by the time we get to the user's program
509 # the sequence numbers are alreay at pretty high numbers, which would
510 # be distracting if you're trying to tell OPs apart. Therefore we'd
511 # like to subtract an offset from all the sequence numbers we display,
512 # to restore the simpler view of the world. The trick is to know what
513 # that offset will be, when we're still compiling B::Concise! If we
514 # hardcoded a value, it would have to change every time B::Concise or
515 # other modules we use do. To help a little, what we do here is
516 # compile a little code at the end of the module, and compute the base
517 # sequence number for the user's program as being a small offset
518 # later, so all we have to worry about are changes in the offset.
520 # When you say "perl -MO=Concise -e '$a'", the output should look like:
522 # 4 <@> leave[t1] vKP/REFC ->(end)
524 #^ smallest OP sequence number should be 1
525 # 2 <;> nextstate(main 1 -e:1) v ->3
526 # ^ smallest COP sequence number should be 1
527 # - <1> ex-rv2sv vK/1 ->4
528 # 3 <$> gvsv(*a) s ->4
530 # If either of the marked numbers there aren't 1, it means you need to
531 # update the corresponding magic number in the next two lines.
532 # Remember, these need to stay the last things in the module.
534 # Why these are different for MacOS? Does it matter?
535 my $cop_seq_mnum = $^O eq 'MacOS' ? 12 : 11;
536 my $seq_mnum = $^O eq 'MacOS' ? 100 : 84;
537 $cop_seq_base = svref_2object(eval 'sub{0;}')->START->cop_seq + $cop_seq_mnum;
538 $seq_base = svref_2object(eval 'sub{}')->START->seq + $seq_mnum;
546 B::Concise - Walk Perl syntax tree, printing concise info about ops
550 perl -MO=Concise[,OPTIONS] foo.pl
552 use B::Concise qw(set_style add_callback);
556 This compiler backend prints the internal OPs of a Perl program's syntax
557 tree in one of several space-efficient text formats suitable for debugging
558 the inner workings of perl or other compiler backends. It can print OPs in
559 the order they appear in the OP tree, in the order they will execute, or
560 in a text approximation to their tree structure, and the format of the
561 information displyed is customizable. Its function is similar to that of
562 perl's B<-Dx> debugging flag or the B<B::Terse> module, but it is more
563 sophisticated and flexible.
567 Here's is a short example of output, using the default formatting
570 % perl -MO=Concise -e '$a = $b + 42'
571 8 <@> leave[t1] vKP/REFC ->(end)
573 2 <;> nextstate(main 1 -e:1) v ->3
574 7 <2> sassign vKS/2 ->8
575 5 <2> add[t1] sK/2 ->6
576 - <1> ex-rv2sv sK/1 ->4
578 4 <$> const(IV 42) s ->5
579 - <1> ex-rv2sv sKRM*/1 ->7
582 Each line corresponds to an operator. Null ops appear as C<ex-opname>,
583 where I<opname> is the op that has been optimized away by perl.
585 The number on the first row indicates the op's sequence number. It's
586 given in base 36 by default.
588 The symbol between angle brackets indicates the op's type : for example,
589 <2> is a BINOP, <@> a LISTOP, etc. (see L</"OP class abbreviations">).
591 The opname may be followed by op-specific information in parentheses
592 (e.g. C<gvsv(*b)>), and by targ information in brackets (e.g.
595 Next come the op flags. The common flags are listed below
596 (L</"OP flags abbreviations">). The private flags follow, separated
597 by a slash. For example, C<vKP/REFC> means that the leave op has
598 public flags OPf_WANT_VOID, OPf_KIDS, and OPf_PARENS, and the private
601 Finally an arrow points to the sequence number of the next op.
605 Arguments that don't start with a hyphen are taken to be the names of
606 subroutines to print the OPs of; if no such functions are specified, the
607 main body of the program (outside any subroutines, and not including use'd
608 or require'd files) is printed.
614 Print OPs in the order they appear in the OP tree (a preorder
615 traversal, starting at the root). The indentation of each OP shows its
616 level in the tree. This mode is the default, so the flag is included
617 simply for completeness.
621 Print OPs in the order they would normally execute (for the majority
622 of constructs this is a postorder traversal of the tree, ending at the
623 root). In most cases the OP that usually follows a given OP will
624 appear directly below it; alternate paths are shown by indentation. In
625 cases like loops when control jumps out of a linear path, a 'goto'
630 Print OPs in a text approximation of a tree, with the root of the tree
631 at the left and 'left-to-right' order of children transformed into
632 'top-to-bottom'. Because this mode grows both to the right and down,
633 it isn't suitable for large programs (unless you have a very wide
638 Use a tree format in which the minimum amount of space is used for the
639 lines connecting nodes (one character in most cases). This squeezes out
640 a few precious columns of screen real estate.
644 Use a tree format that uses longer edges to separate OP nodes. This format
645 tends to look better than the compact one, especially in ASCII, and is
650 Use tree connecting characters drawn from the VT100 line-drawing set.
651 This looks better if your terminal supports it.
655 Draw the tree with standard ASCII characters like C<+> and C<|>. These don't
656 look as clean as the VT100 characters, but they'll work with almost any
657 terminal (or the horizontal scrolling mode of less(1)) and are suitable
658 for text documentation or email. This is the default.
662 Include the main program in the output, even if subroutines were also
667 Print OP sequence numbers in base I<n>. If I<n> is greater than 10, the
668 digit for 11 will be 'a', and so on. If I<n> is greater than 36, the digit
669 for 37 will be 'A', and so on until 62. Values greater than 62 are not
670 currently supported. The default is 36.
674 Print sequence numbers with the most significant digit first. This is the
675 usual convention for Arabic numerals, and the default.
677 =item B<-littleendian>
679 Print seqence numbers with the least significant digit first.
683 Use the author's favorite set of formatting conventions. This is the
688 Use formatting conventions that emulate the ouput of B<B::Terse>. The
689 basic mode is almost indistinguishable from the real B<B::Terse>, and the
690 exec mode looks very similar, but is in a more logical order and lacks
691 curly brackets. B<B::Terse> doesn't have a tree mode, so the tree mode
692 is only vaguely reminiscient of B<B::Terse>.
696 Use formatting conventions in which the name of each OP, rather than being
697 written out in full, is represented by a one- or two-character abbreviation.
698 This is mainly a joke.
702 Use formatting conventions reminiscient of B<B::Debug>; these aren't
707 Use formatting conventions read from the environment variables
708 C<B_CONCISE_FORMAT>, C<B_CONCISE_GOTO_FORMAT>, and C<B_CONCISE_TREE_FORMAT>.
712 =head1 FORMATTING SPECIFICATIONS
714 For each general style ('concise', 'terse', 'linenoise', etc.) there are
715 three specifications: one of how OPs should appear in the basic or exec
716 modes, one of how 'goto' lines should appear (these occur in the exec
717 mode only), and one of how nodes should appear in tree mode. Each has the
718 same format, described below. Any text that doesn't match a special
719 pattern is copied verbatim.
723 =item B<(x(>I<exec_text>B<;>I<basic_text>B<)x)>
725 Generates I<exec_text> in exec mode, or I<basic_text> in basic mode.
727 =item B<(*(>I<text>B<)*)>
729 Generates one copy of I<text> for each indentation level.
731 =item B<(*(>I<text1>B<;>I<text2>B<)*)>
733 Generates one fewer copies of I<text1> than the indentation level, followed
734 by one copy of I<text2> if the indentation level is more than 0.
736 =item B<(?(>I<text1>B<#>I<var>I<Text2>B<)?)>
738 If the value of I<var> is true (not empty or zero), generates the
739 value of I<var> surrounded by I<text1> and I<Text2>, otherwise
744 Generates the value of the variable I<var>.
748 Generates the value of I<var>, left jutified to fill I<N> spaces.
752 Any number of tildes and surrounding whitespace will be collapsed to
757 The following variables are recognized:
763 The address of the OP, in hexidecimal.
767 The OP-specific information of the OP (such as the SV for an SVOP, the
768 non-local exit pointers for a LOOP, etc.) enclosed in paretheses.
772 The B-determined class of the OP, in all caps.
776 A single symbol abbreviating the class of the OP.
780 The label of the statement or block the OP is the start of, if any.
784 The name of the OP, or 'ex-foo' if the OP is a null that used to be a foo.
788 The target of the OP, or nothing for a nulled OP.
792 The address of the OP's first child, in hexidecimal.
796 The OP's flags, abbreviated as a series of symbols.
800 The numeric value of the OP's flags.
804 The sequence number of the OP, or a hyphen if it doesn't have one.
808 'NEXT', 'LAST', or 'REDO' if the OP is a target of one of those in exec
809 mode, or empty otherwise.
813 The address of the OP's last child, in hexidecimal.
821 The OP's name, in all caps.
825 The sequence number of the OP's next OP.
829 The address of the OP's next OP, in hexidecimal.
833 The two-character abbreviation for the OP's name.
837 The OP's private flags, rendered with abbreviated names if possible.
841 The numeric value of the OP's private flags.
845 The sequence number of the OP.
849 The real sequence number of the OP, as a regular number and not adjusted
850 to be relative to the start of the real program. (This will generally be
851 a fairly large number because all of B<B::Concise> is compiled before
856 The address of the OP's next youngest sibling, in hexidecimal.
860 The address of the OP's SV, if it has an SV, in hexidecimal.
864 The class of the OP's SV, if it has one, in all caps (e.g., 'IV').
868 The value of the OP's SV, if it has one, in a short human-readable format.
872 The numeric value of the OP's targ.
876 The name of the variable the OP's targ refers to, if any, otherwise the
877 letter t followed by the OP's targ in decimal.
879 =item B<#targarglife>
881 Same as B<#targarg>, but followed by the COP sequence numbers that delimit
882 the variable's lifetime (or 'end' for a variable in an open scope) for a
887 The numeric value of the OP's type, in decimal.
893 =head2 OP flags abbreviations
895 v OPf_WANT_VOID Want nothing (void context)
896 s OPf_WANT_SCALAR Want single value (scalar context)
897 l OPf_WANT_LIST Want list of any length (list context)
898 K OPf_KIDS There is a firstborn child.
899 P OPf_PARENS This operator was parenthesized.
900 (Or block needs explicit scope entry.)
901 R OPf_REF Certified reference.
902 (Return container, not containee).
903 M OPf_MOD Will modify (lvalue).
904 S OPf_STACKED Some arg is arriving on the stack.
905 * OPf_SPECIAL Do something weird for this op (see op.h)
907 =head2 OP class abbreviations
909 0 OP (aka BASEOP) An OP with no children
910 1 UNOP An OP with one child
911 2 BINOP An OP with two children
912 | LOGOP A control branch OP
913 @ LISTOP An OP that could have lots of children
914 / PMOP An OP with a regular expression
915 $ SVOP An OP with an SV
916 " PVOP An OP with a string
917 { LOOP An OP that holds pointers for a loop
918 ; COP An OP that marks the start of a statement
919 # PADOP An OP with a GV on the pad
921 =head1 Using B::Concise outside of the O framework
923 It is possible to extend B<B::Concise> by using it outside of the B<O>
924 framework and providing new styles and new variables.
926 use B::Concise qw(set_style add_callback);
927 set_style($format, $gotofmt, $treefmt);
932 my ($h, $op, $level, $format) = @_;
933 $h->{variable} = some_func($op);
936 B::Concise::compile(@options)->();
938 You can specify a style by calling the B<set_style> subroutine. If you
939 have a new variable in your style, or you want to change the value of an
940 existing variable, you will need to add a callback to specify the value
943 This is done by calling B<add_callback> passing references to any
944 callback subroutines. The subroutines are called in the same order as
945 they are added. Each subroutine is passed four parameters. These are a
946 reference to a hash, the keys of which are the names of the variables
947 and the values of which are their values, the op, the level and the
950 To define your own variables, simply add them to the hash, or change
951 existing values if you need to. The level and format are passed in as
952 references to scalars, but it is unlikely that they will need to be
953 changed or even used.
955 To see the output, call the subroutine returned by B<compile> in the
956 same way that B<O> does.
960 Stephen McCamant, C<smcc@CSUA.Berkeley.EDU>