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{"aassign"}{32} = "PHASH";
278 $priv{"sassign"}{64} = "BKWARD";
279 $priv{$_}{64} = "RTIME" for ("match", "subst", "substcont");
280 @{$priv{"trans"}}{1,2,4,8,16,64} = ("<UTF", ">UTF", "IDENT", "SQUASH", "DEL",
282 $priv{"repeat"}{64} = "DOLIST";
283 $priv{"leaveloop"}{64} = "CONT";
284 @{$priv{$_}}{32,64,96} = ("DREFAV", "DREFHV", "DREFSV")
285 for ("entersub", map("rv2${_}v", "a", "s", "h", "g"), "aelem", "helem");
286 $priv{"entersub"}{16} = "DBG";
287 $priv{"entersub"}{32} = "TARG";
288 @{$priv{$_}}{4,8,128} = ("INARGS","AMPER","NO()") for ("entersub", "rv2cv");
289 $priv{"gv"}{32} = "EARLYCV";
290 $priv{"aelem"}{16} = $priv{"helem"}{16} = "LVDEFER";
291 $priv{$_}{16} = "OURINTR" for ("gvsv", "rv2sv", "rv2av", "rv2hv", "r2gv");
292 $priv{$_}{16} = "TARGMY"
293 for (map(($_,"s$_"),"chop", "chomp"),
294 map(($_,"i_$_"), "postinc", "postdec", "multiply", "divide", "modulo",
295 "add", "subtract", "negate"), "pow", "concat", "stringify",
296 "left_shift", "right_shift", "bit_and", "bit_xor", "bit_or",
297 "complement", "atan2", "sin", "cos", "rand", "exp", "log", "sqrt",
298 "int", "hex", "oct", "abs", "length", "index", "rindex", "sprintf",
299 "ord", "chr", "crypt", "quotemeta", "join", "push", "unshift", "flock",
300 "chdir", "chown", "chroot", "unlink", "chmod", "utime", "rename",
301 "link", "symlink", "mkdir", "rmdir", "wait", "waitpid", "system",
302 "exec", "kill", "getppid", "getpgrp", "setpgrp", "getpriority",
303 "setpriority", "time", "sleep");
304 @{$priv{"const"}}{8,16,32,64,128} = ("STRICT","ENTERED", '$[', "BARE", "WARN");
305 $priv{"flip"}{64} = $priv{"flop"}{64} = "LINENUM";
306 $priv{"list"}{64} = "GUESSED";
307 $priv{"delete"}{64} = "SLICE";
308 $priv{"exists"}{64} = "SUB";
309 $priv{$_}{64} = "LOCALE"
310 for ("sort", "prtf", "sprintf", "slt", "sle", "seq", "sne", "sgt", "sge",
311 "scmp", "lc", "uc", "lcfirst", "ucfirst");
312 @{$priv{"sort"}}{1,2,4} = ("NUM", "INT", "REV");
313 $priv{"threadsv"}{64} = "SVREFd";
314 $priv{$_}{16} = "INBIN" for ("open", "backtick");
315 $priv{$_}{32} = "INCR" for ("open", "backtick");
316 $priv{$_}{64} = "OUTBIN" for ("open", "backtick");
317 $priv{$_}{128} = "OUTCR" for ("open", "backtick");
318 $priv{"exit"}{128} = "VMS";
323 for my $flag (128, 96, 64, 32, 16, 8, 4, 2, 1) {
324 if ($priv{$name}{$flag} and $x & $flag and $x >= $flag) {
326 push @s, $priv{$name}{$flag};
330 return join(",", @s);
334 my ($op, $level, $format) = @_;
336 $h{exname} = $h{name} = $op->name;
337 $h{NAME} = uc $h{name};
338 $h{class} = class($op);
339 $h{extarg} = $h{targ} = $op->targ;
340 $h{extarg} = "" unless $h{extarg};
341 if ($h{name} eq "null" and $h{targ}) {
342 $h{exname} = "ex-" . substr(ppname($h{targ}), 3);
345 my $padname = (($curcv->PADLIST->ARRAY)[0]->ARRAY)[$h{targ}];
346 if (defined $padname and class($padname) ne "SPECIAL") {
347 $h{targarg} = $padname->PVX;
348 my $intro = $padname->NVX - $cop_seq_base;
349 my $finish = int($padname->IVX) - $cop_seq_base;
350 $finish = "end" if $finish == 999999999 - $cop_seq_base;
351 $h{targarglife} = "$h{targarg}:$intro,$finish";
353 $h{targarglife} = $h{targarg} = "t" . $h{targ};
357 $h{svclass} = $h{svaddr} = $h{svval} = "";
358 if ($h{class} eq "PMOP") {
359 my $precomp = $op->precomp;
360 if (defined $precomp) {
361 # Escape literal control sequences
363 s/\t/\\t/g; s/\n/\\n/g; s/\r/\\r/g;
364 # How can we do the below portably?
365 #s/([\0-\037\177-\377])/"\\".sprintf("%03o", ord($1))/eg;
367 $precomp = "/$precomp/";
369 else { $precomp = ""; }
370 my $pmreplroot = $op->pmreplroot;
372 if ($$pmreplroot && $pmreplroot->isa("B::GV")) {
373 # with C<@stash_array = split(/pat/, str);>,
374 # *stash_array is stored in pmreplroot.
375 $h{arg} = "($precomp => \@" . $pmreplroot->NAME . ")";
376 } elsif ($ {$op->pmreplstart}) {
378 $pmreplstart = "replstart->" . seq($op->pmreplstart);
379 $h{arg} = "(" . join(" ", $precomp, $pmreplstart) . ")";
381 $h{arg} = "($precomp)";
383 } elsif ($h{class} eq "PVOP" and $h{name} ne "trans") {
384 $h{arg} = '("' . $op->pv . '")';
385 $h{svval} = '"' . $op->pv . '"';
386 } elsif ($h{class} eq "COP") {
387 my $label = $op->label;
388 $h{coplabel} = $label;
389 $label = $label ? "$label: " : "";
392 $loc .= ":" . $op->line;
393 my($stash, $cseq) = ($op->stash->NAME, $op->cop_seq - $cop_seq_base);
394 my $arybase = $op->arybase;
395 $arybase = $arybase ? ' $[=' . $arybase : "";
396 $h{arg} = "($label$stash $cseq $loc$arybase)";
397 } elsif ($h{class} eq "LOOP") {
398 $h{arg} = "(next->" . seq($op->nextop) . " last->" . seq($op->lastop)
399 . " redo->" . seq($op->redoop) . ")";
400 } elsif ($h{class} eq "LOGOP") {
402 $h{arg} = "(other->" . seq($op->other) . ")";
403 } elsif ($h{class} eq "SVOP") {
405 $h{svclass} = class($sv);
406 $h{svaddr} = sprintf("%#x", $$sv);
407 if ($h{svclass} eq "GV") {
409 my $stash = $gv->STASH->NAME;
410 if ($stash eq "main") {
413 $stash = $stash . "::";
415 $h{arg} = "(*$stash" . $gv->SAFENAME . ")";
416 $h{svval} = "*$stash" . $gv->SAFENAME;
418 while (class($sv) eq "RV") {
422 if (class($sv) eq "SPECIAL") {
423 $h{svval} = ["Null", "sv_undef", "sv_yes", "sv_no"]->[$$sv];
424 } elsif ($sv->FLAGS & SVf_NOK) {
426 } elsif ($sv->FLAGS & SVf_IOK) {
428 } elsif ($sv->FLAGS & SVf_POK) {
429 $h{svval} = cstring($sv->PV);
431 $h{arg} = "($h{svclass} $h{svval})";
434 $h{seq} = $h{hyphseq} = seq($op);
435 $h{seq} = "" if $h{seq} eq "-";
436 $h{seqnum} = $op->seq;
437 $h{next} = $op->next;
438 $h{next} = (class($h{next}) eq "NULL") ? "(end)" : seq($h{next});
439 $h{nextaddr} = sprintf("%#x", $ {$op->next});
440 $h{sibaddr} = sprintf("%#x", $ {$op->sibling});
441 $h{firstaddr} = sprintf("%#x", $ {$op->first}) if $op->can("first");
442 $h{lastaddr} = sprintf("%#x", $ {$op->last}) if $op->can("last");
444 $h{classsym} = $opclass{$h{class}};
445 $h{flagval} = $op->flags;
446 $h{flags} = op_flags($op->flags);
447 $h{privval} = $op->private;
448 $h{private} = private_flags($h{name}, $op->private);
449 $h{addr} = sprintf("%#x", $$op);
450 $h{label} = $labels{$op->seq};
451 $h{typenum} = $op->type;
452 $h{noise} = $linenoise[$op->type];
453 $_->(\%h, $op, \$format, \$level) for @callbacks;
454 return fmt_line(\%h, $format, $level);
458 my($op, $level) = @_;
459 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
460 my $h = {"seq" => seq($lastnext), "class" => class($lastnext),
461 "addr" => sprintf("%#x", $$lastnext)};
462 print fmt_line($h, $gotofmt, $level+1);
464 $lastnext = $op->next;
465 print concise_op($op, $level, $format);
471 my $style = $tree_decorations[$tree_style];
472 my($space, $single, $kids, $kid, $nokid, $last, $lead, $size) = @$style;
473 my $name = concise_op($op, $level, $treefmt);
474 if (not $op->flags & OPf_KIDS) {
478 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
479 push @lines, tree($kid, $level+1);
482 for ($i = $#lines; substr($lines[$i], 0, 1) eq " "; $i--) {
483 $lines[$i] = $space . $lines[$i];
486 $lines[$i] = $last . $lines[$i];
488 if (substr($lines[$i], 0, 1) eq " ") {
489 $lines[$i] = $nokid . $lines[$i];
491 $lines[$i] = $kid . $lines[$i];
494 $lines[$i] = $kids . $lines[$i];
496 $lines[0] = $single . $lines[0];
498 return("$name$lead" . shift @lines,
499 map(" " x (length($name)+$size) . $_, @lines));
502 # *** Warning: fragile kludge ahead ***
503 # Because the B::* modules run in the same interpreter as the code
504 # they're compiling, their presence tends to distort the view we have
505 # of the code we're looking at. In particular, perl gives sequence
506 # numbers to both OPs in general and COPs in particular. If the
507 # program we're looking at were run on its own, these numbers would
508 # start at 1. Because all of B::Concise and all the modules it uses
509 # are compiled first, though, by the time we get to the user's program
510 # the sequence numbers are alreay at pretty high numbers, which would
511 # be distracting if you're trying to tell OPs apart. Therefore we'd
512 # like to subtract an offset from all the sequence numbers we display,
513 # to restore the simpler view of the world. The trick is to know what
514 # that offset will be, when we're still compiling B::Concise! If we
515 # hardcoded a value, it would have to change every time B::Concise or
516 # other modules we use do. To help a little, what we do here is
517 # compile a little code at the end of the module, and compute the base
518 # sequence number for the user's program as being a small offset
519 # later, so all we have to worry about are changes in the offset.
521 # When you say "perl -MO=Concise -e '$a'", the output should look like:
523 # 4 <@> leave[t1] vKP/REFC ->(end)
525 #^ smallest OP sequence number should be 1
526 # 2 <;> nextstate(main 1 -e:1) v ->3
527 # ^ smallest COP sequence number should be 1
528 # - <1> ex-rv2sv vK/1 ->4
529 # 3 <$> gvsv(*a) s ->4
531 # If either of the marked numbers there aren't 1, it means you need to
532 # update the corresponding magic number in the next two lines.
533 # Remember, these need to stay the last things in the module.
535 # Why these are different for MacOS? Does it matter?
536 my $cop_seq_mnum = $^O eq 'MacOS' ? 12 : 11;
537 my $seq_mnum = $^O eq 'MacOS' ? 100 : 84;
538 $cop_seq_base = svref_2object(eval 'sub{0;}')->START->cop_seq + $cop_seq_mnum;
539 $seq_base = svref_2object(eval 'sub{}')->START->seq + $seq_mnum;
547 B::Concise - Walk Perl syntax tree, printing concise info about ops
551 perl -MO=Concise[,OPTIONS] foo.pl
553 use B::Concise qw(set_style add_callback);
557 This compiler backend prints the internal OPs of a Perl program's syntax
558 tree in one of several space-efficient text formats suitable for debugging
559 the inner workings of perl or other compiler backends. It can print OPs in
560 the order they appear in the OP tree, in the order they will execute, or
561 in a text approximation to their tree structure, and the format of the
562 information displyed is customizable. Its function is similar to that of
563 perl's B<-Dx> debugging flag or the B<B::Terse> module, but it is more
564 sophisticated and flexible.
568 Here's is a short example of output, using the default formatting
571 % perl -MO=Concise -e '$a = $b + 42'
572 8 <@> leave[t1] vKP/REFC ->(end)
574 2 <;> nextstate(main 1 -e:1) v ->3
575 7 <2> sassign vKS/2 ->8
576 5 <2> add[t1] sK/2 ->6
577 - <1> ex-rv2sv sK/1 ->4
579 4 <$> const(IV 42) s ->5
580 - <1> ex-rv2sv sKRM*/1 ->7
583 Each line corresponds to an operator. Null ops appear as C<ex-opname>,
584 where I<opname> is the op that has been optimized away by perl.
586 The number on the first row indicates the op's sequence number. It's
587 given in base 36 by default.
589 The symbol between angle brackets indicates the op's type : for example,
590 <2> is a BINOP, <@> a LISTOP, etc. (see L</"OP class abbreviations">).
592 The opname may be followed by op-specific information in parentheses
593 (e.g. C<gvsv(*b)>), and by targ information in brackets (e.g.
596 Next come the op flags. The common flags are listed below
597 (L</"OP flags abbreviations">). The private flags follow, separated
598 by a slash. For example, C<vKP/REFC> means that the leave op has
599 public flags OPf_WANT_VOID, OPf_KIDS, and OPf_PARENS, and the private
602 Finally an arrow points to the sequence number of the next op.
606 Arguments that don't start with a hyphen are taken to be the names of
607 subroutines to print the OPs of; if no such functions are specified, the
608 main body of the program (outside any subroutines, and not including use'd
609 or require'd files) is printed.
615 Print OPs in the order they appear in the OP tree (a preorder
616 traversal, starting at the root). The indentation of each OP shows its
617 level in the tree. This mode is the default, so the flag is included
618 simply for completeness.
622 Print OPs in the order they would normally execute (for the majority
623 of constructs this is a postorder traversal of the tree, ending at the
624 root). In most cases the OP that usually follows a given OP will
625 appear directly below it; alternate paths are shown by indentation. In
626 cases like loops when control jumps out of a linear path, a 'goto'
631 Print OPs in a text approximation of a tree, with the root of the tree
632 at the left and 'left-to-right' order of children transformed into
633 'top-to-bottom'. Because this mode grows both to the right and down,
634 it isn't suitable for large programs (unless you have a very wide
639 Use a tree format in which the minimum amount of space is used for the
640 lines connecting nodes (one character in most cases). This squeezes out
641 a few precious columns of screen real estate.
645 Use a tree format that uses longer edges to separate OP nodes. This format
646 tends to look better than the compact one, especially in ASCII, and is
651 Use tree connecting characters drawn from the VT100 line-drawing set.
652 This looks better if your terminal supports it.
656 Draw the tree with standard ASCII characters like C<+> and C<|>. These don't
657 look as clean as the VT100 characters, but they'll work with almost any
658 terminal (or the horizontal scrolling mode of less(1)) and are suitable
659 for text documentation or email. This is the default.
663 Include the main program in the output, even if subroutines were also
668 Print OP sequence numbers in base I<n>. If I<n> is greater than 10, the
669 digit for 11 will be 'a', and so on. If I<n> is greater than 36, the digit
670 for 37 will be 'A', and so on until 62. Values greater than 62 are not
671 currently supported. The default is 36.
675 Print sequence numbers with the most significant digit first. This is the
676 usual convention for Arabic numerals, and the default.
678 =item B<-littleendian>
680 Print seqence numbers with the least significant digit first.
684 Use the author's favorite set of formatting conventions. This is the
689 Use formatting conventions that emulate the ouput of B<B::Terse>. The
690 basic mode is almost indistinguishable from the real B<B::Terse>, and the
691 exec mode looks very similar, but is in a more logical order and lacks
692 curly brackets. B<B::Terse> doesn't have a tree mode, so the tree mode
693 is only vaguely reminiscient of B<B::Terse>.
697 Use formatting conventions in which the name of each OP, rather than being
698 written out in full, is represented by a one- or two-character abbreviation.
699 This is mainly a joke.
703 Use formatting conventions reminiscient of B<B::Debug>; these aren't
708 Use formatting conventions read from the environment variables
709 C<B_CONCISE_FORMAT>, C<B_CONCISE_GOTO_FORMAT>, and C<B_CONCISE_TREE_FORMAT>.
713 =head1 FORMATTING SPECIFICATIONS
715 For each general style ('concise', 'terse', 'linenoise', etc.) there are
716 three specifications: one of how OPs should appear in the basic or exec
717 modes, one of how 'goto' lines should appear (these occur in the exec
718 mode only), and one of how nodes should appear in tree mode. Each has the
719 same format, described below. Any text that doesn't match a special
720 pattern is copied verbatim.
724 =item B<(x(>I<exec_text>B<;>I<basic_text>B<)x)>
726 Generates I<exec_text> in exec mode, or I<basic_text> in basic mode.
728 =item B<(*(>I<text>B<)*)>
730 Generates one copy of I<text> for each indentation level.
732 =item B<(*(>I<text1>B<;>I<text2>B<)*)>
734 Generates one fewer copies of I<text1> than the indentation level, followed
735 by one copy of I<text2> if the indentation level is more than 0.
737 =item B<(?(>I<text1>B<#>I<var>I<Text2>B<)?)>
739 If the value of I<var> is true (not empty or zero), generates the
740 value of I<var> surrounded by I<text1> and I<Text2>, otherwise
745 Generates the value of the variable I<var>.
749 Generates the value of I<var>, left jutified to fill I<N> spaces.
753 Any number of tildes and surrounding whitespace will be collapsed to
758 The following variables are recognized:
764 The address of the OP, in hexidecimal.
768 The OP-specific information of the OP (such as the SV for an SVOP, the
769 non-local exit pointers for a LOOP, etc.) enclosed in paretheses.
773 The B-determined class of the OP, in all caps.
777 A single symbol abbreviating the class of the OP.
781 The label of the statement or block the OP is the start of, if any.
785 The name of the OP, or 'ex-foo' if the OP is a null that used to be a foo.
789 The target of the OP, or nothing for a nulled OP.
793 The address of the OP's first child, in hexidecimal.
797 The OP's flags, abbreviated as a series of symbols.
801 The numeric value of the OP's flags.
805 The sequence number of the OP, or a hyphen if it doesn't have one.
809 'NEXT', 'LAST', or 'REDO' if the OP is a target of one of those in exec
810 mode, or empty otherwise.
814 The address of the OP's last child, in hexidecimal.
822 The OP's name, in all caps.
826 The sequence number of the OP's next OP.
830 The address of the OP's next OP, in hexidecimal.
834 The two-character abbreviation for the OP's name.
838 The OP's private flags, rendered with abbreviated names if possible.
842 The numeric value of the OP's private flags.
846 The sequence number of the OP.
850 The real sequence number of the OP, as a regular number and not adjusted
851 to be relative to the start of the real program. (This will generally be
852 a fairly large number because all of B<B::Concise> is compiled before
857 The address of the OP's next youngest sibling, in hexidecimal.
861 The address of the OP's SV, if it has an SV, in hexidecimal.
865 The class of the OP's SV, if it has one, in all caps (e.g., 'IV').
869 The value of the OP's SV, if it has one, in a short human-readable format.
873 The numeric value of the OP's targ.
877 The name of the variable the OP's targ refers to, if any, otherwise the
878 letter t followed by the OP's targ in decimal.
880 =item B<#targarglife>
882 Same as B<#targarg>, but followed by the COP sequence numbers that delimit
883 the variable's lifetime (or 'end' for a variable in an open scope) for a
888 The numeric value of the OP's type, in decimal.
894 =head2 OP flags abbreviations
896 v OPf_WANT_VOID Want nothing (void context)
897 s OPf_WANT_SCALAR Want single value (scalar context)
898 l OPf_WANT_LIST Want list of any length (list context)
899 K OPf_KIDS There is a firstborn child.
900 P OPf_PARENS This operator was parenthesized.
901 (Or block needs explicit scope entry.)
902 R OPf_REF Certified reference.
903 (Return container, not containee).
904 M OPf_MOD Will modify (lvalue).
905 S OPf_STACKED Some arg is arriving on the stack.
906 * OPf_SPECIAL Do something weird for this op (see op.h)
908 =head2 OP class abbreviations
910 0 OP (aka BASEOP) An OP with no children
911 1 UNOP An OP with one child
912 2 BINOP An OP with two children
913 | LOGOP A control branch OP
914 @ LISTOP An OP that could have lots of children
915 / PMOP An OP with a regular expression
916 $ SVOP An OP with an SV
917 " PVOP An OP with a string
918 { LOOP An OP that holds pointers for a loop
919 ; COP An OP that marks the start of a statement
920 # PADOP An OP with a GV on the pad
922 =head1 Using B::Concise outside of the O framework
924 It is possible to extend B<B::Concise> by using it outside of the B<O>
925 framework and providing new styles and new variables.
927 use B::Concise qw(set_style add_callback);
928 set_style($format, $gotofmt, $treefmt);
933 my ($h, $op, $level, $format) = @_;
934 $h->{variable} = some_func($op);
937 B::Concise::compile(@options)->();
939 You can specify a style by calling the B<set_style> subroutine. If you
940 have a new variable in your style, or you want to change the value of an
941 existing variable, you will need to add a callback to specify the value
944 This is done by calling B<add_callback> passing references to any
945 callback subroutines. The subroutines are called in the same order as
946 they are added. Each subroutine is passed four parameters. These are a
947 reference to a hash, the keys of which are the names of the variables
948 and the values of which are their values, the op, the level and the
951 To define your own variables, simply add them to the hash, or change
952 existing values if you need to. The level and format are passed in as
953 references to scalars, but it is unlikely that they will need to be
954 changed or even used.
956 To see the output, call the subroutine returned by B<compile> in the
957 same way that B<O> does.
961 Stephen McCamant, C<smcc@CSUA.Berkeley.EDU>