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Make Data::Dumper work when dynamic extensions are not available
[perl5.git] / ext / Data / Dumper / Dumper.pm
CommitLineData
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1#
2# Data/Dumper.pm
3#
4# convert perl data structures into perl syntax suitable for both printing
5# and eval
6#
7# Documentation at the __END__
8#
9
10package Data::Dumper;
11
907e5114 12$VERSION = '2.121_04';
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13
14#$| = 1;
15
3b825e41 16use 5.006_001;
823edd99 17require Exporter;
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18require overload;
19
20use Carp;
21
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JB
22BEGIN {
23 @ISA = qw(Exporter);
24 @EXPORT = qw(Dumper);
25 @EXPORT_OK = qw(DumperX);
823edd99 26
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27 # if run under miniperl, or otherwise lacking dynamic loading,
28 # XSLoader should be attempted to load, or the pure perl flag
29 # toggled on load failure.
30 eval {
31 require XSLoader;
32 XSLoader::load( 'Data::Dumper' );
33 1;
34 };
35 $Useperl = 1 if $@;
36}
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37
38# module vars and their defaults
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JB
39$Indent = 2 unless defined $Indent;
40$Purity = 0 unless defined $Purity;
41$Pad = "" unless defined $Pad;
42$Varname = "VAR" unless defined $Varname;
43$Useqq = 0 unless defined $Useqq;
44$Terse = 0 unless defined $Terse;
45$Freezer = "" unless defined $Freezer;
46$Toaster = "" unless defined $Toaster;
47$Deepcopy = 0 unless defined $Deepcopy;
48$Quotekeys = 1 unless defined $Quotekeys;
49$Bless = "bless" unless defined $Bless;
50#$Expdepth = 0 unless defined $Expdepth;
51$Maxdepth = 0 unless defined $Maxdepth;
52$Pair = ' => ' unless defined $Pair;
53$Useperl = 0 unless defined $Useperl;
54$Sortkeys = 0 unless defined $Sortkeys;
55$Deparse = 0 unless defined $Deparse;
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56
57#
58# expects an arrayref of values to be dumped.
59# can optionally pass an arrayref of names for the values.
60# names must have leading $ sign stripped. begin the name with *
61# to cause output of arrays and hashes rather than refs.
62#
63sub new {
64 my($c, $v, $n) = @_;
65
66 croak "Usage: PACKAGE->new(ARRAYREF, [ARRAYREF])"
67 unless (defined($v) && (ref($v) eq 'ARRAY'));
68 $n = [] unless (defined($n) && (ref($v) eq 'ARRAY'));
69
70 my($s) = {
71 level => 0, # current recursive depth
72 indent => $Indent, # various styles of indenting
73 pad => $Pad, # all lines prefixed by this string
74 xpad => "", # padding-per-level
75 apad => "", # added padding for hash keys n such
76 sep => "", # list separator
30b4f386 77 pair => $Pair, # hash key/value separator: defaults to ' => '
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78 seen => {}, # local (nested) refs (id => [name, val])
79 todump => $v, # values to dump []
80 names => $n, # optional names for values []
81 varname => $Varname, # prefix to use for tagging nameless ones
82 purity => $Purity, # degree to which output is evalable
83 useqq => $Useqq, # use "" for strings (backslashitis ensues)
84 terse => $Terse, # avoid name output (where feasible)
85 freezer => $Freezer, # name of Freezer method for objects
86 toaster => $Toaster, # name of method to revive objects
87 deepcopy => $Deepcopy, # dont cross-ref, except to stop recursion
88 quotekeys => $Quotekeys, # quote hash keys
89 'bless' => $Bless, # keyword to use for "bless"
90# expdepth => $Expdepth, # cutoff depth for explicit dumping
a2126434 91 maxdepth => $Maxdepth, # depth beyond which we give up
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92 useperl => $Useperl, # use the pure Perl implementation
93 sortkeys => $Sortkeys, # flag or filter for sorting hash keys
8e5f9a6e 94 deparse => $Deparse, # use B::Deparse for coderefs
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95 };
96
97 if ($Indent > 0) {
98 $s->{xpad} = " ";
99 $s->{sep} = "\n";
100 }
101 return bless($s, $c);
102}
103
104#
105# add-to or query the table of already seen references
106#
107sub Seen {
108 my($s, $g) = @_;
109 if (defined($g) && (ref($g) eq 'HASH')) {
110 my($k, $v, $id);
111 while (($k, $v) = each %$g) {
112 if (defined $v and ref $v) {
113 ($id) = (overload::StrVal($v) =~ /\((.*)\)$/);
114 if ($k =~ /^[*](.*)$/) {
115 $k = (ref $v eq 'ARRAY') ? ( "\\\@" . $1 ) :
116 (ref $v eq 'HASH') ? ( "\\\%" . $1 ) :
117 (ref $v eq 'CODE') ? ( "\\\&" . $1 ) :
118 ( "\$" . $1 ) ;
119 }
120 elsif ($k !~ /^\$/) {
121 $k = "\$" . $k;
122 }
123 $s->{seen}{$id} = [$k, $v];
124 }
125 else {
126 carp "Only refs supported, ignoring non-ref item \$$k";
127 }
128 }
129 return $s;
130 }
131 else {
132 return map { @$_ } values %{$s->{seen}};
133 }
134}
135
136#
137# set or query the values to be dumped
138#
139sub Values {
140 my($s, $v) = @_;
141 if (defined($v) && (ref($v) eq 'ARRAY')) {
142 $s->{todump} = [@$v]; # make a copy
143 return $s;
144 }
145 else {
146 return @{$s->{todump}};
147 }
148}
149
150#
151# set or query the names of the values to be dumped
152#
153sub Names {
154 my($s, $n) = @_;
155 if (defined($n) && (ref($n) eq 'ARRAY')) {
156 $s->{names} = [@$n]; # make a copy
157 return $s;
158 }
159 else {
160 return @{$s->{names}};
161 }
162}
163
164sub DESTROY {}
165
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166sub Dump {
167 return &Dumpxs
31a725b3 168 unless $Data::Dumper::Useperl || (ref($_[0]) && $_[0]->{useperl}) ||
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169 $Data::Dumper::Useqq || (ref($_[0]) && $_[0]->{useqq}) ||
170 $Data::Dumper::Deparse || (ref($_[0]) && $_[0]->{deparse});
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171 return &Dumpperl;
172}
173
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174#
175# dump the refs in the current dumper object.
176# expects same args as new() if called via package name.
177#
0f1923bd 178sub Dumpperl {
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179 my($s) = shift;
180 my(@out, $val, $name);
181 my($i) = 0;
182 local(@post);
183
184 $s = $s->new(@_) unless ref $s;
185
186 for $val (@{$s->{todump}}) {
187 my $out = "";
188 @post = ();
189 $name = $s->{names}[$i++];
190 if (defined $name) {
191 if ($name =~ /^[*](.*)$/) {
192 if (defined $val) {
193 $name = (ref $val eq 'ARRAY') ? ( "\@" . $1 ) :
194 (ref $val eq 'HASH') ? ( "\%" . $1 ) :
195 (ref $val eq 'CODE') ? ( "\*" . $1 ) :
196 ( "\$" . $1 ) ;
197 }
198 else {
199 $name = "\$" . $1;
200 }
201 }
202 elsif ($name !~ /^\$/) {
203 $name = "\$" . $name;
204 }
205 }
206 else {
207 $name = "\$" . $s->{varname} . $i;
208 }
209
210 my $valstr;
211 {
212 local($s->{apad}) = $s->{apad};
213 $s->{apad} .= ' ' x (length($name) + 3) if $s->{indent} >= 2;
214 $valstr = $s->_dump($val, $name);
215 }
216
217 $valstr = "$name = " . $valstr . ';' if @post or !$s->{terse};
218 $out .= $s->{pad} . $valstr . $s->{sep};
219 $out .= $s->{pad} . join(';' . $s->{sep} . $s->{pad}, @post)
220 . ';' . $s->{sep} if @post;
221
222 push @out, $out;
223 }
224 return wantarray ? @out : join('', @out);
225}
226
227#
228# twist, toil and turn;
229# and recurse, of course.
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230# sometimes sordidly;
231# and curse if no recourse.
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232#
233sub _dump {
234 my($s, $val, $name) = @_;
235 my($sname);
236 my($out, $realpack, $realtype, $type, $ipad, $id, $blesspad);
237
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238 $type = ref $val;
239 $out = "";
240
241 if ($type) {
242
c5f7c514
ST
243 # Call the freezer method if it's specified and the object has the
244 # method. Trap errors and warn() instead of die()ing, like the XS
245 # implementation.
246 my $freezer = $s->{freezer};
247 if ($freezer and UNIVERSAL::can($val, $freezer)) {
248 eval { $val->$freezer() };
249 warn "WARNING(Freezer method call failed): $@" if $@;
823edd99
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250 }
251
252 ($realpack, $realtype, $id) =
253 (overload::StrVal($val) =~ /^(?:(.*)\=)?([^=]*)\(([^\(]*)\)$/);
a2126434 254
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255 # if it has a name, we need to either look it up, or keep a tab
256 # on it so we know when we hit it later
257 if (defined($name) and length($name)) {
258 # keep a tab on it so that we dont fall into recursive pit
259 if (exists $s->{seen}{$id}) {
260# if ($s->{expdepth} < $s->{level}) {
261 if ($s->{purity} and $s->{level} > 0) {
262 $out = ($realtype eq 'HASH') ? '{}' :
263 ($realtype eq 'ARRAY') ? '[]' :
5df59fb6 264 'do{my $o}' ;
7820172a 265 push @post, $name . " = " . $s->{seen}{$id}[0];
823edd99
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266 }
267 else {
7820172a
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268 $out = $s->{seen}{$id}[0];
269 if ($name =~ /^([\@\%])/) {
270 my $start = $1;
271 if ($out =~ /^\\$start/) {
272 $out = substr($out, 1);
273 }
274 else {
275 $out = $start . '{' . $out . '}';
276 }
277 }
278 }
279 return $out;
280# }
281 }
282 else {
283 # store our name
284 $s->{seen}{$id} = [ (($name =~ /^[@%]/) ? ('\\' . $name ) :
285 ($realtype eq 'CODE' and
286 $name =~ /^[*](.*)$/) ? ('\\&' . $1 ) :
287 $name ),
288 $val ];
823edd99 289 }
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290 }
291
a2126434 292 if ($realpack and $realpack eq 'Regexp') {
7894fbab
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293 $out = "$val";
294 $out =~ s,/,\\/,g;
295 return "qr/$out/";
a2126434
JN
296 }
297
298 # If purity is not set and maxdepth is set, then check depth:
299 # if we have reached maximum depth, return the string
300 # representation of the thing we are currently examining
301 # at this depth (i.e., 'Foo=ARRAY(0xdeadbeef)').
302 if (!$s->{purity}
303 and $s->{maxdepth} > 0
304 and $s->{level} >= $s->{maxdepth})
305 {
306 return qq['$val'];
307 }
308
309 # we have a blessed ref
310 if ($realpack) {
311 $out = $s->{'bless'} . '( ';
312 $blesspad = $s->{apad};
313 $s->{apad} .= ' ' if ($s->{indent} >= 2);
7894fbab
GS
314 }
315
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316 $s->{level}++;
317 $ipad = $s->{xpad} x $s->{level};
318
54964f74 319 if ($realtype eq 'SCALAR' || $realtype eq 'REF') {
823edd99 320 if ($realpack) {
7820172a 321 $out .= 'do{\\(my $o = ' . $s->_dump($$val, "\${$name}") . ')}';
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GS
322 }
323 else {
7820172a 324 $out .= '\\' . $s->_dump($$val, "\${$name}");
823edd99
GS
325 }
326 }
327 elsif ($realtype eq 'GLOB') {
7820172a 328 $out .= '\\' . $s->_dump($$val, "*{$name}");
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329 }
330 elsif ($realtype eq 'ARRAY') {
331 my($v, $pad, $mname);
332 my($i) = 0;
333 $out .= ($name =~ /^\@/) ? '(' : '[';
334 $pad = $s->{sep} . $s->{pad} . $s->{apad};
335 ($name =~ /^\@(.*)$/) ? ($mname = "\$" . $1) :
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336 # omit -> if $foo->[0]->{bar}, but not ${$foo->[0]}->{bar}
337 ($name =~ /^\\?[\%\@\*\$][^{].*[]}]$/) ? ($mname = $name) :
338 ($mname = $name . '->');
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339 $mname .= '->' if $mname =~ /^\*.+\{[A-Z]+\}$/;
340 for $v (@$val) {
341 $sname = $mname . '[' . $i . ']';
342 $out .= $pad . $ipad . '#' . $i if $s->{indent} >= 3;
343 $out .= $pad . $ipad . $s->_dump($v, $sname);
344 $out .= "," if $i++ < $#$val;
345 }
346 $out .= $pad . ($s->{xpad} x ($s->{level} - 1)) if $i;
347 $out .= ($name =~ /^\@/) ? ')' : ']';
348 }
349 elsif ($realtype eq 'HASH') {
30b4f386 350 my($k, $v, $pad, $lpad, $mname, $pair);
823edd99
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351 $out .= ($name =~ /^\%/) ? '(' : '{';
352 $pad = $s->{sep} . $s->{pad} . $s->{apad};
353 $lpad = $s->{apad};
30b4f386 354 $pair = $s->{pair};
7820172a
GS
355 ($name =~ /^\%(.*)$/) ? ($mname = "\$" . $1) :
356 # omit -> if $foo->[0]->{bar}, but not ${$foo->[0]}->{bar}
357 ($name =~ /^\\?[\%\@\*\$][^{].*[]}]$/) ? ($mname = $name) :
358 ($mname = $name . '->');
823edd99 359 $mname .= '->' if $mname =~ /^\*.+\{[A-Z]+\}$/;
31a725b3
JH
360 my ($sortkeys, $keys, $key) = ("$s->{sortkeys}");
361 if ($sortkeys) {
362 if (ref($s->{sortkeys}) eq 'CODE') {
363 $keys = $s->{sortkeys}($val);
364 unless (ref($keys) eq 'ARRAY') {
365 carp "Sortkeys subroutine did not return ARRAYREF";
366 $keys = [];
367 }
368 }
369 else {
370 $keys = [ sort keys %$val ];
371 }
372 }
373 while (($k, $v) = ! $sortkeys ? (each %$val) :
374 @$keys ? ($key = shift(@$keys), $val->{$key}) :
375 () )
376 {
823edd99
GS
377 my $nk = $s->_dump($k, "");
378 $nk = $1 if !$s->{quotekeys} and $nk =~ /^[\"\']([A-Za-z_]\w*)[\"\']$/;
379 $sname = $mname . '{' . $nk . '}';
30b4f386 380 $out .= $pad . $ipad . $nk . $pair;
823edd99
GS
381
382 # temporarily alter apad
383 $s->{apad} .= (" " x (length($nk) + 4)) if $s->{indent} >= 2;
384 $out .= $s->_dump($val->{$k}, $sname) . ",";
385 $s->{apad} = $lpad if $s->{indent} >= 2;
386 }
387 if (substr($out, -1) eq ',') {
388 chop $out;
389 $out .= $pad . ($s->{xpad} x ($s->{level} - 1));
390 }
391 $out .= ($name =~ /^\%/) ? ')' : '}';
392 }
393 elsif ($realtype eq 'CODE') {
8e5f9a6e
RGS
394 if ($s->{deparse}) {
395 require B::Deparse;
396 my $sub = 'sub ' . (B::Deparse->new)->coderef2text($val);
41a63c2f 397 $pad = $s->{sep} . $s->{pad} . $s->{apad} . $s->{xpad} x ($s->{level} - 1);
8e5f9a6e
RGS
398 $sub =~ s/\n/$pad/gse;
399 $out .= $sub;
400 } else {
401 $out .= 'sub { "DUMMY" }';
402 carp "Encountered CODE ref, using dummy placeholder" if $s->{purity};
403 }
823edd99
GS
404 }
405 else {
406 croak "Can\'t handle $realtype type.";
407 }
408
409 if ($realpack) { # we have a blessed ref
410 $out .= ', \'' . $realpack . '\'' . ' )';
411 $out .= '->' . $s->{toaster} . '()' if $s->{toaster} ne '';
412 $s->{apad} = $blesspad;
413 }
414 $s->{level}--;
415
416 }
417 else { # simple scalar
418
419 my $ref = \$_[1];
420 # first, catalog the scalar
421 if ($name ne '') {
422 ($id) = ("$ref" =~ /\(([^\(]*)\)$/);
423 if (exists $s->{seen}{$id}) {
7820172a
GS
424 if ($s->{seen}{$id}[2]) {
425 $out = $s->{seen}{$id}[0];
426 #warn "[<$out]\n";
427 return "\${$out}";
428 }
823edd99
GS
429 }
430 else {
7820172a
GS
431 #warn "[>\\$name]\n";
432 $s->{seen}{$id} = ["\\$name", $ref];
823edd99
GS
433 }
434 }
435 if (ref($ref) eq 'GLOB' or "$ref" =~ /=GLOB\([^()]+\)$/) { # glob
436 my $name = substr($val, 1);
437 if ($name =~ /^[A-Za-z_][\w:]*$/) {
438 $name =~ s/^main::/::/;
439 $sname = $name;
440 }
441 else {
442 $sname = $s->_dump($name, "");
443 $sname = '{' . $sname . '}';
444 }
445 if ($s->{purity}) {
446 my $k;
447 local ($s->{level}) = 0;
448 for $k (qw(SCALAR ARRAY HASH)) {
7820172a
GS
449 my $gval = *$val{$k};
450 next unless defined $gval;
451 next if $k eq "SCALAR" && ! defined $$gval; # always there
452
823edd99
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453 # _dump can push into @post, so we hold our place using $postlen
454 my $postlen = scalar @post;
455 $post[$postlen] = "\*$sname = ";
456 local ($s->{apad}) = " " x length($post[$postlen]) if $s->{indent} >= 2;
7820172a 457 $post[$postlen] .= $s->_dump($gval, "\*$sname\{$k\}");
823edd99
GS
458 }
459 }
460 $out .= '*' . $sname;
461 }
7820172a
GS
462 elsif (!defined($val)) {
463 $out .= "undef";
464 }
c4cce848 465 elsif ($val =~ /^(?:0|-?[1-9]\d{0,8})\z/) { # safe decimal number
823edd99
GS
466 $out .= $val;
467 }
468 else { # string
c4cce848
NC
469 if ($s->{useqq} or $val =~ tr/\0-\377//c) {
470 # Fall back to qq if there's unicode
7820172a 471 $out .= qquote($val, $s->{useqq});
823edd99
GS
472 }
473 else {
474 $val =~ s/([\\\'])/\\$1/g;
475 $out .= '\'' . $val . '\'';
476 }
477 }
478 }
7820172a
GS
479 if ($id) {
480 # if we made it this far, $id was added to seen list at current
481 # level, so remove it to get deep copies
482 if ($s->{deepcopy}) {
483 delete($s->{seen}{$id});
484 }
485 elsif ($name) {
486 $s->{seen}{$id}[2] = 1;
487 }
488 }
823edd99
GS
489 return $out;
490}
491
492#
493# non-OO style of earlier version
494#
495sub Dumper {
496 return Data::Dumper->Dump([@_]);
497}
498
0f1923bd 499# compat stub
823edd99
GS
500sub DumperX {
501 return Data::Dumper->Dumpxs([@_], []);
502}
503
504sub Dumpf { return Data::Dumper->Dump(@_) }
505
506sub Dumpp { print Data::Dumper->Dump(@_) }
507
508#
509# reset the "seen" cache
510#
511sub Reset {
512 my($s) = shift;
513 $s->{seen} = {};
514 return $s;
515}
516
517sub Indent {
518 my($s, $v) = @_;
519 if (defined($v)) {
520 if ($v == 0) {
521 $s->{xpad} = "";
522 $s->{sep} = "";
523 }
524 else {
525 $s->{xpad} = " ";
526 $s->{sep} = "\n";
527 }
528 $s->{indent} = $v;
529 return $s;
530 }
531 else {
532 return $s->{indent};
533 }
534}
535
30b4f386 536sub Pair {
537 my($s, $v) = @_;
538 defined($v) ? (($s->{pair} = $v), return $s) : $s->{pair};
539}
540
823edd99
GS
541sub Pad {
542 my($s, $v) = @_;
543 defined($v) ? (($s->{pad} = $v), return $s) : $s->{pad};
544}
545
546sub Varname {
547 my($s, $v) = @_;
548 defined($v) ? (($s->{varname} = $v), return $s) : $s->{varname};
549}
550
551sub Purity {
552 my($s, $v) = @_;
553 defined($v) ? (($s->{purity} = $v), return $s) : $s->{purity};
554}
555
556sub Useqq {
557 my($s, $v) = @_;
558 defined($v) ? (($s->{useqq} = $v), return $s) : $s->{useqq};
559}
560
561sub Terse {
562 my($s, $v) = @_;
563 defined($v) ? (($s->{terse} = $v), return $s) : $s->{terse};
564}
565
566sub Freezer {
567 my($s, $v) = @_;
568 defined($v) ? (($s->{freezer} = $v), return $s) : $s->{freezer};
569}
570
571sub Toaster {
572 my($s, $v) = @_;
573 defined($v) ? (($s->{toaster} = $v), return $s) : $s->{toaster};
574}
575
576sub Deepcopy {
577 my($s, $v) = @_;
578 defined($v) ? (($s->{deepcopy} = $v), return $s) : $s->{deepcopy};
579}
580
581sub Quotekeys {
582 my($s, $v) = @_;
583 defined($v) ? (($s->{quotekeys} = $v), return $s) : $s->{quotekeys};
584}
585
586sub Bless {
587 my($s, $v) = @_;
588 defined($v) ? (($s->{'bless'} = $v), return $s) : $s->{'bless'};
589}
590
a2126434
JN
591sub Maxdepth {
592 my($s, $v) = @_;
593 defined($v) ? (($s->{'maxdepth'} = $v), return $s) : $s->{'maxdepth'};
594}
595
31a725b3
JH
596sub Useperl {
597 my($s, $v) = @_;
598 defined($v) ? (($s->{'useperl'} = $v), return $s) : $s->{'useperl'};
599}
600
601sub Sortkeys {
602 my($s, $v) = @_;
603 defined($v) ? (($s->{'sortkeys'} = $v), return $s) : $s->{'sortkeys'};
604}
605
8e5f9a6e
RGS
606sub Deparse {
607 my($s, $v) = @_;
608 defined($v) ? (($s->{'deparse'} = $v), return $s) : $s->{'deparse'};
609}
a2126434 610
7820172a
GS
611# used by qquote below
612my %esc = (
613 "\a" => "\\a",
614 "\b" => "\\b",
615 "\t" => "\\t",
616 "\n" => "\\n",
617 "\f" => "\\f",
618 "\r" => "\\r",
619 "\e" => "\\e",
620);
621
823edd99
GS
622# put a string value in double quotes
623sub qquote {
624 local($_) = shift;
7820172a 625 s/([\\\"\@\$])/\\$1/g;
dc71dc59
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626 my $bytes; { use bytes; $bytes = length }
627 s/([^\x00-\x7f])/'\x{'.sprintf("%x",ord($1)).'}'/ge if $bytes > length;
0407a77b
GS
628 return qq("$_") unless
629 /[^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/; # fast exit
7820172a
GS
630
631 my $high = shift || "";
632 s/([\a\b\t\n\f\r\e])/$esc{$1}/g;
633
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GS
634 if (ord('^')==94) { # ascii
635 # no need for 3 digits in escape for these
636 s/([\0-\037])(?!\d)/'\\'.sprintf('%o',ord($1))/eg;
637 s/([\0-\037\177])/'\\'.sprintf('%03o',ord($1))/eg;
43948175 638 # all but last branch below not supported --BEHAVIOR SUBJECT TO CHANGE--
0407a77b
GS
639 if ($high eq "iso8859") {
640 s/([\200-\240])/'\\'.sprintf('%o',ord($1))/eg;
641 } elsif ($high eq "utf8") {
642# use utf8;
643# $str =~ s/([^\040-\176])/sprintf "\\x{%04x}", ord($1)/ge;
644 } elsif ($high eq "8bit") {
645 # leave it as it is
646 } else {
647 s/([\200-\377])/'\\'.sprintf('%03o',ord($1))/eg;
c4cce848 648 s/([^\040-\176])/sprintf "\\x{%04x}", ord($1)/ge;
0407a77b
GS
649 }
650 }
651 else { # ebcdic
43948175
GS
652 s{([^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~])(?!\d)}
653 {my $v = ord($1); '\\'.sprintf(($v <= 037 ? '%o' : '%03o'), $v)}eg;
654 s{([^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~])}
655 {'\\'.sprintf('%03o',ord($1))}eg;
7820172a 656 }
0407a77b 657
7820172a 658 return qq("$_");
823edd99
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659}
660
fec5e1eb
IM
661# helper sub to sort hash keys in Perl < 5.8.0 where we don't have
662# access to sortsv() from XS
663sub _sortkeys { [ sort keys %{$_[0]} ] }
664
823edd99
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6651;
666__END__
667
668=head1 NAME
669
670Data::Dumper - stringified perl data structures, suitable for both printing and C<eval>
671
823edd99
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672=head1 SYNOPSIS
673
674 use Data::Dumper;
675
676 # simple procedural interface
677 print Dumper($foo, $bar);
678
679 # extended usage with names
680 print Data::Dumper->Dump([$foo, $bar], [qw(foo *ary)]);
681
682 # configuration variables
683 {
82df27e1 684 local $Data::Dumper::Purity = 1;
823edd99
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685 eval Data::Dumper->Dump([$foo, $bar], [qw(foo *ary)]);
686 }
687
688 # OO usage
689 $d = Data::Dumper->new([$foo, $bar], [qw(foo *ary)]);
690 ...
691 print $d->Dump;
692 ...
693 $d->Purity(1)->Terse(1)->Deepcopy(1);
694 eval $d->Dump;
695
696
697=head1 DESCRIPTION
698
699Given a list of scalars or reference variables, writes out their contents in
700perl syntax. The references can also be objects. The contents of each
701variable is output in a single Perl statement. Handles self-referential
702structures correctly.
703
704The return value can be C<eval>ed to get back an identical copy of the
fc3a748c 705original reference structure.
823edd99
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706
707Any references that are the same as one of those passed in will be named
708C<$VAR>I<n> (where I<n> is a numeric suffix), and other duplicate references
709to substructures within C<$VAR>I<n> will be appropriately labeled using arrow
710notation. You can specify names for individual values to be dumped if you
711use the C<Dump()> method, or you can change the default C<$VAR> prefix to
712something else. See C<$Data::Dumper::Varname> and C<$Data::Dumper::Terse>
713below.
714
715The default output of self-referential structures can be C<eval>ed, but the
716nested references to C<$VAR>I<n> will be undefined, since a recursive
717structure cannot be constructed using one Perl statement. You should set the
718C<Purity> flag to 1 to get additional statements that will correctly fill in
fc3a748c
RGS
719these references. Moreover, if C<eval>ed when strictures are in effect,
720you need to ensure that any variables it accesses are previously declared.
823edd99
GS
721
722In the extended usage form, the references to be dumped can be given
723user-specified names. If a name begins with a C<*>, the output will
724describe the dereferenced type of the supplied reference for hashes and
725arrays, and coderefs. Output of names will be avoided where possible if
726the C<Terse> flag is set.
727
728In many cases, methods that are used to set the internal state of the
729object will return the object itself, so method calls can be conveniently
730chained together.
731
732Several styles of output are possible, all controlled by setting
733the C<Indent> flag. See L<Configuration Variables or Methods> below
734for details.
735
736
737=head2 Methods
738
739=over 4
740
741=item I<PACKAGE>->new(I<ARRAYREF [>, I<ARRAYREF]>)
742
743Returns a newly created C<Data::Dumper> object. The first argument is an
744anonymous array of values to be dumped. The optional second argument is an
745anonymous array of names for the values. The names need not have a leading
746C<$> sign, and must be comprised of alphanumeric characters. You can begin
747a name with a C<*> to specify that the dereferenced type must be dumped
748instead of the reference itself, for ARRAY and HASH references.
749
750The prefix specified by C<$Data::Dumper::Varname> will be used with a
751numeric suffix if the name for a value is undefined.
752
753Data::Dumper will catalog all references encountered while dumping the
754values. Cross-references (in the form of names of substructures in perl
755syntax) will be inserted at all possible points, preserving any structural
756interdependencies in the original set of values. Structure traversal is
757depth-first, and proceeds in order from the first supplied value to
758the last.
759
760=item I<$OBJ>->Dump I<or> I<PACKAGE>->Dump(I<ARRAYREF [>, I<ARRAYREF]>)
761
762Returns the stringified form of the values stored in the object (preserving
763the order in which they were supplied to C<new>), subject to the
91e74348 764configuration options below. In a list context, it returns a list
823edd99
GS
765of strings corresponding to the supplied values.
766
767The second form, for convenience, simply calls the C<new> method on its
768arguments before dumping the object immediately.
769
823edd99
GS
770=item I<$OBJ>->Seen(I<[HASHREF]>)
771
772Queries or adds to the internal table of already encountered references.
773You must use C<Reset> to explicitly clear the table if needed. Such
774references are not dumped; instead, their names are inserted wherever they
775are encountered subsequently. This is useful especially for properly
776dumping subroutine references.
777
d1be9408 778Expects an anonymous hash of name => value pairs. Same rules apply for names
823edd99 779as in C<new>. If no argument is supplied, will return the "seen" list of
91e74348 780name => value pairs, in a list context. Otherwise, returns the object
823edd99
GS
781itself.
782
783=item I<$OBJ>->Values(I<[ARRAYREF]>)
784
785Queries or replaces the internal array of values that will be dumped.
786When called without arguments, returns the values. Otherwise, returns the
787object itself.
788
789=item I<$OBJ>->Names(I<[ARRAYREF]>)
790
791Queries or replaces the internal array of user supplied names for the values
792that will be dumped. When called without arguments, returns the names.
793Otherwise, returns the object itself.
794
795=item I<$OBJ>->Reset
796
797Clears the internal table of "seen" references and returns the object
798itself.
799
800=back
801
802=head2 Functions
803
804=over 4
805
806=item Dumper(I<LIST>)
807
808Returns the stringified form of the values in the list, subject to the
809configuration options below. The values will be named C<$VAR>I<n> in the
810output, where I<n> is a numeric suffix. Will return a list of strings
91e74348 811in a list context.
823edd99 812
823edd99
GS
813=back
814
815=head2 Configuration Variables or Methods
816
817Several configuration variables can be used to control the kind of output
818generated when using the procedural interface. These variables are usually
819C<local>ized in a block so that other parts of the code are not affected by
820the change.
821
822These variables determine the default state of the object created by calling
823the C<new> method, but cannot be used to alter the state of the object
824thereafter. The equivalent method names should be used instead to query
825or set the internal state of the object.
826
827The method forms return the object itself when called with arguments,
828so that they can be chained together nicely.
829
830=over 4
831
28bf64cc
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832=item *
833
834$Data::Dumper::Indent I<or> I<$OBJ>->Indent(I<[NEWVAL]>)
823edd99
GS
835
836Controls the style of indentation. It can be set to 0, 1, 2 or 3. Style 0
837spews output without any newlines, indentation, or spaces between list
838items. It is the most compact format possible that can still be called
839valid perl. Style 1 outputs a readable form with newlines but no fancy
840indentation (each level in the structure is simply indented by a fixed
841amount of whitespace). Style 2 (the default) outputs a very readable form
842which takes into account the length of hash keys (so the hash value lines
843up). Style 3 is like style 2, but also annotates the elements of arrays
844with their index (but the comment is on its own line, so array output
845consumes twice the number of lines). Style 2 is the default.
846
28bf64cc
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847=item *
848
849$Data::Dumper::Purity I<or> I<$OBJ>->Purity(I<[NEWVAL]>)
823edd99
GS
850
851Controls the degree to which the output can be C<eval>ed to recreate the
852supplied reference structures. Setting it to 1 will output additional perl
853statements that will correctly recreate nested references. The default is
8540.
855
28bf64cc
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856=item *
857
858$Data::Dumper::Pad I<or> I<$OBJ>->Pad(I<[NEWVAL]>)
823edd99
GS
859
860Specifies the string that will be prefixed to every line of the output.
861Empty string by default.
862
28bf64cc
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863=item *
864
865$Data::Dumper::Varname I<or> I<$OBJ>->Varname(I<[NEWVAL]>)
823edd99
GS
866
867Contains the prefix to use for tagging variable names in the output. The
868default is "VAR".
869
28bf64cc
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870=item *
871
872$Data::Dumper::Useqq I<or> I<$OBJ>->Useqq(I<[NEWVAL]>)
823edd99
GS
873
874When set, enables the use of double quotes for representing string values.
875Whitespace other than space will be represented as C<[\n\t\r]>, "unsafe"
876characters will be backslashed, and unprintable characters will be output as
877quoted octal integers. Since setting this variable imposes a performance
0f1923bd
GS
878penalty, the default is 0. C<Dump()> will run slower if this flag is set,
879since the fast XSUB implementation doesn't support it yet.
823edd99 880
28bf64cc
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881=item *
882
883$Data::Dumper::Terse I<or> I<$OBJ>->Terse(I<[NEWVAL]>)
823edd99
GS
884
885When set, Data::Dumper will emit single, non-self-referential values as
886atoms/terms rather than statements. This means that the C<$VAR>I<n> names
887will be avoided where possible, but be advised that such output may not
888always be parseable by C<eval>.
889
28bf64cc
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890=item *
891
892$Data::Dumper::Freezer I<or> $I<OBJ>->Freezer(I<[NEWVAL]>)
823edd99
GS
893
894Can be set to a method name, or to an empty string to disable the feature.
895Data::Dumper will invoke that method via the object before attempting to
896stringify it. This method can alter the contents of the object (if, for
897instance, it contains data allocated from C), and even rebless it in a
898different package. The client is responsible for making sure the specified
899method can be called via the object, and that the object ends up containing
900only perl data types after the method has been called. Defaults to an empty
901string.
902
c5f7c514
ST
903If an object does not support the method specified (determined using
904UNIVERSAL::can()) then the call will be skipped. If the method dies a
905warning will be generated.
906
28bf64cc
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907=item *
908
909$Data::Dumper::Toaster I<or> $I<OBJ>->Toaster(I<[NEWVAL]>)
823edd99
GS
910
911Can be set to a method name, or to an empty string to disable the feature.
912Data::Dumper will emit a method call for any objects that are to be dumped
8e5f9a6e 913using the syntax C<bless(DATA, CLASS)-E<gt>METHOD()>. Note that this means that
823edd99
GS
914the method specified will have to perform any modifications required on the
915object (like creating new state within it, and/or reblessing it in a
916different package) and then return it. The client is responsible for making
917sure the method can be called via the object, and that it returns a valid
918object. Defaults to an empty string.
919
28bf64cc
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920=item *
921
922$Data::Dumper::Deepcopy I<or> $I<OBJ>->Deepcopy(I<[NEWVAL]>)
823edd99
GS
923
924Can be set to a boolean value to enable deep copies of structures.
925Cross-referencing will then only be done when absolutely essential
926(i.e., to break reference cycles). Default is 0.
927
28bf64cc
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928=item *
929
930$Data::Dumper::Quotekeys I<or> $I<OBJ>->Quotekeys(I<[NEWVAL]>)
823edd99
GS
931
932Can be set to a boolean value to control whether hash keys are quoted.
933A false value will avoid quoting hash keys when it looks like a simple
934string. Default is 1, which will always enclose hash keys in quotes.
935
28bf64cc
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936=item *
937
938$Data::Dumper::Bless I<or> $I<OBJ>->Bless(I<[NEWVAL]>)
823edd99
GS
939
940Can be set to a string that specifies an alternative to the C<bless>
941builtin operator used to create objects. A function with the specified
942name should exist, and should accept the same arguments as the builtin.
943Default is C<bless>.
944
28bf64cc
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945=item *
946
30b4f386 947$Data::Dumper::Pair I<or> $I<OBJ>->Pair(I<[NEWVAL]>)
948
949Can be set to a string that specifies the separator between hash keys
950and values. To dump nested hash, array and scalar values to JavaScript,
951use: C<$Data::Dumper::Pair = ' : ';>. Implementing C<bless> in JavaScript
952is left as an exercise for the reader.
953A function with the specified name exists, and accepts the same arguments
954as the builtin.
955
956Default is: C< =E<gt> >.
957
958=item *
959
28bf64cc 960$Data::Dumper::Maxdepth I<or> $I<OBJ>->Maxdepth(I<[NEWVAL]>)
a2126434
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961
962Can be set to a positive integer that specifies the depth beyond which
963which we don't venture into a structure. Has no effect when
964C<Data::Dumper::Purity> is set. (Useful in debugger when we often don't
965want to see more than enough). Default is 0, which means there is
966no maximum depth.
967
28bf64cc
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968=item *
969
970$Data::Dumper::Useperl I<or> $I<OBJ>->Useperl(I<[NEWVAL]>)
31a725b3
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971
972Can be set to a boolean value which controls whether the pure Perl
973implementation of C<Data::Dumper> is used. The C<Data::Dumper> module is
974a dual implementation, with almost all functionality written in both
975pure Perl and also in XS ('C'). Since the XS version is much faster, it
976will always be used if possible. This option lets you override the
977default behavior, usually for testing purposes only. Default is 0, which
978means the XS implementation will be used if possible.
979
28bf64cc
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980=item *
981
982$Data::Dumper::Sortkeys I<or> $I<OBJ>->Sortkeys(I<[NEWVAL]>)
31a725b3
JH
983
984Can be set to a boolean value to control whether hash keys are dumped in
985sorted order. A true value will cause the keys of all hashes to be
986dumped in Perl's default sort order. Can also be set to a subroutine
987reference which will be called for each hash that is dumped. In this
988case C<Data::Dumper> will call the subroutine once for each hash,
989passing it the reference of the hash. The purpose of the subroutine is
990to return a reference to an array of the keys that will be dumped, in
991the order that they should be dumped. Using this feature, you can
992control both the order of the keys, and which keys are actually used. In
993other words, this subroutine acts as a filter by which you can exclude
994certain keys from being dumped. Default is 0, which means that hash keys
995are not sorted.
996
28bf64cc
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997=item *
998
999$Data::Dumper::Deparse I<or> $I<OBJ>->Deparse(I<[NEWVAL]>)
8e5f9a6e
RGS
1000
1001Can be set to a boolean value to control whether code references are
1002turned into perl source code. If set to a true value, C<B::Deparse>
1003will be used to get the source of the code reference. Using this option
1004will force using the Perl implementation of the dumper, since the fast
1005XSUB implementation doesn't support it.
1006
1007Caution : use this option only if you know that your coderefs will be
1008properly reconstructed by C<B::Deparse>.
1009
823edd99
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1010=back
1011
1012=head2 Exports
1013
1014=over 4
1015
1016=item Dumper
1017
1018=back
1019
1020=head1 EXAMPLES
1021
1022Run these code snippets to get a quick feel for the behavior of this
1023module. When you are through with these examples, you may want to
1024add or change the various configuration variables described above,
1025to see their behavior. (See the testsuite in the Data::Dumper
1026distribution for more examples.)
1027
1028
1029 use Data::Dumper;
1030
1031 package Foo;
1032 sub new {bless {'a' => 1, 'b' => sub { return "foo" }}, $_[0]};
1033
1034 package Fuz; # a weird REF-REF-SCALAR object
1035 sub new {bless \($_ = \ 'fu\'z'), $_[0]};
1036
1037 package main;
1038 $foo = Foo->new;
1039 $fuz = Fuz->new;
1040 $boo = [ 1, [], "abcd", \*foo,
1041 {1 => 'a', 023 => 'b', 0x45 => 'c'},
1042 \\"p\q\'r", $foo, $fuz];
3cb6de81 1043
823edd99
GS
1044 ########
1045 # simple usage
1046 ########
1047
1048 $bar = eval(Dumper($boo));
1049 print($@) if $@;
1050 print Dumper($boo), Dumper($bar); # pretty print (no array indices)
1051
1052 $Data::Dumper::Terse = 1; # don't output names where feasible
1053 $Data::Dumper::Indent = 0; # turn off all pretty print
1054 print Dumper($boo), "\n";
1055
1056 $Data::Dumper::Indent = 1; # mild pretty print
1057 print Dumper($boo);
1058
1059 $Data::Dumper::Indent = 3; # pretty print with array indices
1060 print Dumper($boo);
1061
1062 $Data::Dumper::Useqq = 1; # print strings in double quotes
1063 print Dumper($boo);
3cb6de81 1064
30b4f386 1065 $Data::Dumper::Pair = " : "; # specify hash key/value separator
1066 print Dumper($boo);
1067
3cb6de81 1068
823edd99
GS
1069 ########
1070 # recursive structures
1071 ########
3cb6de81 1072
823edd99
GS
1073 @c = ('c');
1074 $c = \@c;
1075 $b = {};
1076 $a = [1, $b, $c];
1077 $b->{a} = $a;
1078 $b->{b} = $a->[1];
1079 $b->{c} = $a->[2];
1080 print Data::Dumper->Dump([$a,$b,$c], [qw(a b c)]);
3cb6de81
GS
1081
1082
823edd99
GS
1083 $Data::Dumper::Purity = 1; # fill in the holes for eval
1084 print Data::Dumper->Dump([$a, $b], [qw(*a b)]); # print as @a
1085 print Data::Dumper->Dump([$b, $a], [qw(*b a)]); # print as %b
3cb6de81
GS
1086
1087
823edd99
GS
1088 $Data::Dumper::Deepcopy = 1; # avoid cross-refs
1089 print Data::Dumper->Dump([$b, $a], [qw(*b a)]);
3cb6de81
GS
1090
1091
823edd99
GS
1092 $Data::Dumper::Purity = 0; # avoid cross-refs
1093 print Data::Dumper->Dump([$b, $a], [qw(*b a)]);
3cb6de81 1094
a2126434
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1095 ########
1096 # deep structures
1097 ########
3cb6de81 1098
a2126434
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1099 $a = "pearl";
1100 $b = [ $a ];
1101 $c = { 'b' => $b };
1102 $d = [ $c ];
1103 $e = { 'd' => $d };
1104 $f = { 'e' => $e };
1105 print Data::Dumper->Dump([$f], [qw(f)]);
1106
1107 $Data::Dumper::Maxdepth = 3; # no deeper than 3 refs down
1108 print Data::Dumper->Dump([$f], [qw(f)]);
1109
3cb6de81 1110
823edd99
GS
1111 ########
1112 # object-oriented usage
1113 ########
3cb6de81 1114
823edd99
GS
1115 $d = Data::Dumper->new([$a,$b], [qw(a b)]);
1116 $d->Seen({'*c' => $c}); # stash a ref without printing it
1117 $d->Indent(3);
1118 print $d->Dump;
1119 $d->Reset->Purity(0); # empty the seen cache
1120 print join "----\n", $d->Dump;
3cb6de81
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1121
1122
823edd99
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1123 ########
1124 # persistence
1125 ########
3cb6de81 1126
823edd99
GS
1127 package Foo;
1128 sub new { bless { state => 'awake' }, shift }
1129 sub Freeze {
1130 my $s = shift;
1131 print STDERR "preparing to sleep\n";
1132 $s->{state} = 'asleep';
1133 return bless $s, 'Foo::ZZZ';
1134 }
3cb6de81 1135
823edd99
GS
1136 package Foo::ZZZ;
1137 sub Thaw {
1138 my $s = shift;
1139 print STDERR "waking up\n";
1140 $s->{state} = 'awake';
1141 return bless $s, 'Foo';
1142 }
3cb6de81 1143
823edd99
GS
1144 package Foo;
1145 use Data::Dumper;
1146 $a = Foo->new;
1147 $b = Data::Dumper->new([$a], ['c']);
1148 $b->Freezer('Freeze');
1149 $b->Toaster('Thaw');
1150 $c = $b->Dump;
1151 print $c;
1152 $d = eval $c;
1153 print Data::Dumper->Dump([$d], ['d']);
3cb6de81
GS
1154
1155
823edd99
GS
1156 ########
1157 # symbol substitution (useful for recreating CODE refs)
1158 ########
3cb6de81 1159
823edd99
GS
1160 sub foo { print "foo speaking\n" }
1161 *other = \&foo;
1162 $bar = [ \&other ];
1163 $d = Data::Dumper->new([\&other,$bar],['*other','bar']);
1164 $d->Seen({ '*foo' => \&foo });
1165 print $d->Dump;
1166
1167
31a725b3
JH
1168 ########
1169 # sorting and filtering hash keys
1170 ########
1171
1172 $Data::Dumper::Sortkeys = \&my_filter;
1173 my $foo = { map { (ord, "$_$_$_") } 'I'..'Q' };
1174 my $bar = { %$foo };
1175 my $baz = { reverse %$foo };
1176 print Dumper [ $foo, $bar, $baz ];
1177
1178 sub my_filter {
1179 my ($hash) = @_;
1180 # return an array ref containing the hash keys to dump
1181 # in the order that you want them to be dumped
1182 return [
1183 # Sort the keys of %$foo in reverse numeric order
1184 $hash eq $foo ? (sort {$b <=> $a} keys %$hash) :
1185 # Only dump the odd number keys of %$bar
1186 $hash eq $bar ? (grep {$_ % 2} keys %$hash) :
1187 # Sort keys in default order for all other hashes
1188 (sort keys %$hash)
1189 ];
1190 }
1191
823edd99
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1192=head1 BUGS
1193
1194Due to limitations of Perl subroutine call semantics, you cannot pass an
1195array or hash. Prepend it with a C<\> to pass its reference instead. This
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1196will be remedied in time, now that Perl has subroutine prototypes.
1197For now, you need to use the extended usage form, and prepend the
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1198name with a C<*> to output it as a hash or array.
1199
1200C<Data::Dumper> cheats with CODE references. If a code reference is
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1201encountered in the structure being processed (and if you haven't set
1202the C<Deparse> flag), an anonymous subroutine that
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1203contains the string '"DUMMY"' will be inserted in its place, and a warning
1204will be printed if C<Purity> is set. You can C<eval> the result, but bear
1205in mind that the anonymous sub that gets created is just a placeholder.
1206Someday, perl will have a switch to cache-on-demand the string
1207representation of a compiled piece of code, I hope. If you have prior
1208knowledge of all the code refs that your data structures are likely
1209to have, you can use the C<Seen> method to pre-seed the internal reference
1210table and make the dumped output point to them, instead. See L<EXAMPLES>
1211above.
1212
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1213The C<Useqq> and C<Deparse> flags makes Dump() run slower, since the
1214XSUB implementation does not support them.
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1215
1216SCALAR objects have the weirdest looking C<bless> workaround.
1217
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IM
1218Pure Perl version of C<Data::Dumper> escapes UTF-8 strings correctly
1219only in Perl 5.8.0 and later.
1220
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JH
1221=head2 NOTE
1222
1223Starting from Perl 5.8.1 different runs of Perl will have different
1224ordering of hash keys. The change was done for greater security,
1225see L<perlsec/"Algorithmic Complexity Attacks">. This means that
1226different runs of Perl will have different Data::Dumper outputs if
1227the data contains hashes. If you need to have identical Data::Dumper
1228outputs from different runs of Perl, use the environment variable
1229PERL_HASH_SEED, see L<perlrun/PERL_HASH_SEED>. Using this restores
1230the old (platform-specific) ordering: an even prettier solution might
1231be to use the C<Sortkeys> filter of Data::Dumper.
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1232
1233=head1 AUTHOR
1234
6e238990 1235Gurusamy Sarathy gsar@activestate.com
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1236
1237Copyright (c) 1996-98 Gurusamy Sarathy. All rights reserved.
1238This program is free software; you can redistribute it and/or
1239modify it under the same terms as Perl itself.
1240
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1241=head1 VERSION
1242
fec5e1eb 1243Version 2.121 (Aug 24 2003)
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1244
1245=head1 SEE ALSO
1246
1247perl(1)
1248
1249=cut