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86530b38 AT |
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 | ||
10 | package Data::Dumper; | |
11 | ||
12 | $VERSION = '2.12'; | |
13 | ||
14 | #$| = 1; | |
15 | ||
16 | use 5.006_001; | |
17 | require Exporter; | |
18 | use XSLoader (); | |
19 | require overload; | |
20 | ||
21 | use Carp; | |
22 | ||
23 | @ISA = qw(Exporter); | |
24 | @EXPORT = qw(Dumper); | |
25 | @EXPORT_OK = qw(DumperX); | |
26 | ||
27 | XSLoader::load 'Data::Dumper'; | |
28 | ||
29 | # module vars and their defaults | |
30 | $Indent = 2 unless defined $Indent; | |
31 | $Purity = 0 unless defined $Purity; | |
32 | $Pad = "" unless defined $Pad; | |
33 | $Varname = "VAR" unless defined $Varname; | |
34 | $Useqq = 0 unless defined $Useqq; | |
35 | $Terse = 0 unless defined $Terse; | |
36 | $Freezer = "" unless defined $Freezer; | |
37 | $Toaster = "" unless defined $Toaster; | |
38 | $Deepcopy = 0 unless defined $Deepcopy; | |
39 | $Quotekeys = 1 unless defined $Quotekeys; | |
40 | $Bless = "bless" unless defined $Bless; | |
41 | #$Expdepth = 0 unless defined $Expdepth; | |
42 | $Maxdepth = 0 unless defined $Maxdepth; | |
43 | $Useperl = 0 unless defined $Useperl; | |
44 | $Sortkeys = 0 unless defined $Sortkeys; | |
45 | $Deparse = 0 unless defined $Deparse; | |
46 | ||
47 | # | |
48 | # expects an arrayref of values to be dumped. | |
49 | # can optionally pass an arrayref of names for the values. | |
50 | # names must have leading $ sign stripped. begin the name with * | |
51 | # to cause output of arrays and hashes rather than refs. | |
52 | # | |
53 | sub new { | |
54 | my($c, $v, $n) = @_; | |
55 | ||
56 | croak "Usage: PACKAGE->new(ARRAYREF, [ARRAYREF])" | |
57 | unless (defined($v) && (ref($v) eq 'ARRAY')); | |
58 | $n = [] unless (defined($n) && (ref($v) eq 'ARRAY')); | |
59 | ||
60 | my($s) = { | |
61 | level => 0, # current recursive depth | |
62 | indent => $Indent, # various styles of indenting | |
63 | pad => $Pad, # all lines prefixed by this string | |
64 | xpad => "", # padding-per-level | |
65 | apad => "", # added padding for hash keys n such | |
66 | sep => "", # list separator | |
67 | seen => {}, # local (nested) refs (id => [name, val]) | |
68 | todump => $v, # values to dump [] | |
69 | names => $n, # optional names for values [] | |
70 | varname => $Varname, # prefix to use for tagging nameless ones | |
71 | purity => $Purity, # degree to which output is evalable | |
72 | useqq => $Useqq, # use "" for strings (backslashitis ensues) | |
73 | terse => $Terse, # avoid name output (where feasible) | |
74 | freezer => $Freezer, # name of Freezer method for objects | |
75 | toaster => $Toaster, # name of method to revive objects | |
76 | deepcopy => $Deepcopy, # dont cross-ref, except to stop recursion | |
77 | quotekeys => $Quotekeys, # quote hash keys | |
78 | 'bless' => $Bless, # keyword to use for "bless" | |
79 | # expdepth => $Expdepth, # cutoff depth for explicit dumping | |
80 | maxdepth => $Maxdepth, # depth beyond which we give up | |
81 | useperl => $Useperl, # use the pure Perl implementation | |
82 | sortkeys => $Sortkeys, # flag or filter for sorting hash keys | |
83 | deparse => $Deparse, # use B::Deparse for coderefs | |
84 | }; | |
85 | ||
86 | if ($Indent > 0) { | |
87 | $s->{xpad} = " "; | |
88 | $s->{sep} = "\n"; | |
89 | } | |
90 | return bless($s, $c); | |
91 | } | |
92 | ||
93 | # | |
94 | # add-to or query the table of already seen references | |
95 | # | |
96 | sub Seen { | |
97 | my($s, $g) = @_; | |
98 | if (defined($g) && (ref($g) eq 'HASH')) { | |
99 | my($k, $v, $id); | |
100 | while (($k, $v) = each %$g) { | |
101 | if (defined $v and ref $v) { | |
102 | ($id) = (overload::StrVal($v) =~ /\((.*)\)$/); | |
103 | if ($k =~ /^[*](.*)$/) { | |
104 | $k = (ref $v eq 'ARRAY') ? ( "\\\@" . $1 ) : | |
105 | (ref $v eq 'HASH') ? ( "\\\%" . $1 ) : | |
106 | (ref $v eq 'CODE') ? ( "\\\&" . $1 ) : | |
107 | ( "\$" . $1 ) ; | |
108 | } | |
109 | elsif ($k !~ /^\$/) { | |
110 | $k = "\$" . $k; | |
111 | } | |
112 | $s->{seen}{$id} = [$k, $v]; | |
113 | } | |
114 | else { | |
115 | carp "Only refs supported, ignoring non-ref item \$$k"; | |
116 | } | |
117 | } | |
118 | return $s; | |
119 | } | |
120 | else { | |
121 | return map { @$_ } values %{$s->{seen}}; | |
122 | } | |
123 | } | |
124 | ||
125 | # | |
126 | # set or query the values to be dumped | |
127 | # | |
128 | sub Values { | |
129 | my($s, $v) = @_; | |
130 | if (defined($v) && (ref($v) eq 'ARRAY')) { | |
131 | $s->{todump} = [@$v]; # make a copy | |
132 | return $s; | |
133 | } | |
134 | else { | |
135 | return @{$s->{todump}}; | |
136 | } | |
137 | } | |
138 | ||
139 | # | |
140 | # set or query the names of the values to be dumped | |
141 | # | |
142 | sub Names { | |
143 | my($s, $n) = @_; | |
144 | if (defined($n) && (ref($n) eq 'ARRAY')) { | |
145 | $s->{names} = [@$n]; # make a copy | |
146 | return $s; | |
147 | } | |
148 | else { | |
149 | return @{$s->{names}}; | |
150 | } | |
151 | } | |
152 | ||
153 | sub DESTROY {} | |
154 | ||
155 | sub Dump { | |
156 | return &Dumpxs | |
157 | unless $Data::Dumper::Useperl || (ref($_[0]) && $_[0]->{useperl}) || | |
158 | $Data::Dumper::Useqq || (ref($_[0]) && $_[0]->{useqq}) || | |
159 | $Data::Dumper::Deparse || (ref($_[0]) && $_[0]->{deparse}); | |
160 | return &Dumpperl; | |
161 | } | |
162 | ||
163 | # | |
164 | # dump the refs in the current dumper object. | |
165 | # expects same args as new() if called via package name. | |
166 | # | |
167 | sub Dumpperl { | |
168 | my($s) = shift; | |
169 | my(@out, $val, $name); | |
170 | my($i) = 0; | |
171 | local(@post); | |
172 | ||
173 | $s = $s->new(@_) unless ref $s; | |
174 | ||
175 | for $val (@{$s->{todump}}) { | |
176 | my $out = ""; | |
177 | @post = (); | |
178 | $name = $s->{names}[$i++]; | |
179 | if (defined $name) { | |
180 | if ($name =~ /^[*](.*)$/) { | |
181 | if (defined $val) { | |
182 | $name = (ref $val eq 'ARRAY') ? ( "\@" . $1 ) : | |
183 | (ref $val eq 'HASH') ? ( "\%" . $1 ) : | |
184 | (ref $val eq 'CODE') ? ( "\*" . $1 ) : | |
185 | ( "\$" . $1 ) ; | |
186 | } | |
187 | else { | |
188 | $name = "\$" . $1; | |
189 | } | |
190 | } | |
191 | elsif ($name !~ /^\$/) { | |
192 | $name = "\$" . $name; | |
193 | } | |
194 | } | |
195 | else { | |
196 | $name = "\$" . $s->{varname} . $i; | |
197 | } | |
198 | ||
199 | my $valstr; | |
200 | { | |
201 | local($s->{apad}) = $s->{apad}; | |
202 | $s->{apad} .= ' ' x (length($name) + 3) if $s->{indent} >= 2; | |
203 | $valstr = $s->_dump($val, $name); | |
204 | } | |
205 | ||
206 | $valstr = "$name = " . $valstr . ';' if @post or !$s->{terse}; | |
207 | $out .= $s->{pad} . $valstr . $s->{sep}; | |
208 | $out .= $s->{pad} . join(';' . $s->{sep} . $s->{pad}, @post) | |
209 | . ';' . $s->{sep} if @post; | |
210 | ||
211 | push @out, $out; | |
212 | } | |
213 | return wantarray ? @out : join('', @out); | |
214 | } | |
215 | ||
216 | # | |
217 | # twist, toil and turn; | |
218 | # and recurse, of course. | |
219 | # sometimes sordidly; | |
220 | # and curse if no recourse. | |
221 | # | |
222 | sub _dump { | |
223 | my($s, $val, $name) = @_; | |
224 | my($sname); | |
225 | my($out, $realpack, $realtype, $type, $ipad, $id, $blesspad); | |
226 | ||
227 | $type = ref $val; | |
228 | $out = ""; | |
229 | ||
230 | if ($type) { | |
231 | ||
232 | # prep it, if it looks like an object | |
233 | if (my $freezer = $s->{freezer}) { | |
234 | $val->$freezer() if UNIVERSAL::can($val, $freezer); | |
235 | } | |
236 | ||
237 | ($realpack, $realtype, $id) = | |
238 | (overload::StrVal($val) =~ /^(?:(.*)\=)?([^=]*)\(([^\(]*)\)$/); | |
239 | ||
240 | # if it has a name, we need to either look it up, or keep a tab | |
241 | # on it so we know when we hit it later | |
242 | if (defined($name) and length($name)) { | |
243 | # keep a tab on it so that we dont fall into recursive pit | |
244 | if (exists $s->{seen}{$id}) { | |
245 | # if ($s->{expdepth} < $s->{level}) { | |
246 | if ($s->{purity} and $s->{level} > 0) { | |
247 | $out = ($realtype eq 'HASH') ? '{}' : | |
248 | ($realtype eq 'ARRAY') ? '[]' : | |
249 | 'do{my $o}' ; | |
250 | push @post, $name . " = " . $s->{seen}{$id}[0]; | |
251 | } | |
252 | else { | |
253 | $out = $s->{seen}{$id}[0]; | |
254 | if ($name =~ /^([\@\%])/) { | |
255 | my $start = $1; | |
256 | if ($out =~ /^\\$start/) { | |
257 | $out = substr($out, 1); | |
258 | } | |
259 | else { | |
260 | $out = $start . '{' . $out . '}'; | |
261 | } | |
262 | } | |
263 | } | |
264 | return $out; | |
265 | # } | |
266 | } | |
267 | else { | |
268 | # store our name | |
269 | $s->{seen}{$id} = [ (($name =~ /^[@%]/) ? ('\\' . $name ) : | |
270 | ($realtype eq 'CODE' and | |
271 | $name =~ /^[*](.*)$/) ? ('\\&' . $1 ) : | |
272 | $name ), | |
273 | $val ]; | |
274 | } | |
275 | } | |
276 | ||
277 | if ($realpack and $realpack eq 'Regexp') { | |
278 | $out = "$val"; | |
279 | $out =~ s,/,\\/,g; | |
280 | return "qr/$out/"; | |
281 | } | |
282 | ||
283 | # If purity is not set and maxdepth is set, then check depth: | |
284 | # if we have reached maximum depth, return the string | |
285 | # representation of the thing we are currently examining | |
286 | # at this depth (i.e., 'Foo=ARRAY(0xdeadbeef)'). | |
287 | if (!$s->{purity} | |
288 | and $s->{maxdepth} > 0 | |
289 | and $s->{level} >= $s->{maxdepth}) | |
290 | { | |
291 | return qq['$val']; | |
292 | } | |
293 | ||
294 | # we have a blessed ref | |
295 | if ($realpack) { | |
296 | $out = $s->{'bless'} . '( '; | |
297 | $blesspad = $s->{apad}; | |
298 | $s->{apad} .= ' ' if ($s->{indent} >= 2); | |
299 | } | |
300 | ||
301 | $s->{level}++; | |
302 | $ipad = $s->{xpad} x $s->{level}; | |
303 | ||
304 | if ($realtype eq 'SCALAR' || $realtype eq 'REF') { | |
305 | if ($realpack) { | |
306 | $out .= 'do{\\(my $o = ' . $s->_dump($$val, "\${$name}") . ')}'; | |
307 | } | |
308 | else { | |
309 | $out .= '\\' . $s->_dump($$val, "\${$name}"); | |
310 | } | |
311 | } | |
312 | elsif ($realtype eq 'GLOB') { | |
313 | $out .= '\\' . $s->_dump($$val, "*{$name}"); | |
314 | } | |
315 | elsif ($realtype eq 'ARRAY') { | |
316 | my($v, $pad, $mname); | |
317 | my($i) = 0; | |
318 | $out .= ($name =~ /^\@/) ? '(' : '['; | |
319 | $pad = $s->{sep} . $s->{pad} . $s->{apad}; | |
320 | ($name =~ /^\@(.*)$/) ? ($mname = "\$" . $1) : | |
321 | # omit -> if $foo->[0]->{bar}, but not ${$foo->[0]}->{bar} | |
322 | ($name =~ /^\\?[\%\@\*\$][^{].*[]}]$/) ? ($mname = $name) : | |
323 | ($mname = $name . '->'); | |
324 | $mname .= '->' if $mname =~ /^\*.+\{[A-Z]+\}$/; | |
325 | for $v (@$val) { | |
326 | $sname = $mname . '[' . $i . ']'; | |
327 | $out .= $pad . $ipad . '#' . $i if $s->{indent} >= 3; | |
328 | $out .= $pad . $ipad . $s->_dump($v, $sname); | |
329 | $out .= "," if $i++ < $#$val; | |
330 | } | |
331 | $out .= $pad . ($s->{xpad} x ($s->{level} - 1)) if $i; | |
332 | $out .= ($name =~ /^\@/) ? ')' : ']'; | |
333 | } | |
334 | elsif ($realtype eq 'HASH') { | |
335 | my($k, $v, $pad, $lpad, $mname); | |
336 | $out .= ($name =~ /^\%/) ? '(' : '{'; | |
337 | $pad = $s->{sep} . $s->{pad} . $s->{apad}; | |
338 | $lpad = $s->{apad}; | |
339 | ($name =~ /^\%(.*)$/) ? ($mname = "\$" . $1) : | |
340 | # omit -> if $foo->[0]->{bar}, but not ${$foo->[0]}->{bar} | |
341 | ($name =~ /^\\?[\%\@\*\$][^{].*[]}]$/) ? ($mname = $name) : | |
342 | ($mname = $name . '->'); | |
343 | $mname .= '->' if $mname =~ /^\*.+\{[A-Z]+\}$/; | |
344 | my ($sortkeys, $keys, $key) = ("$s->{sortkeys}"); | |
345 | if ($sortkeys) { | |
346 | if (ref($s->{sortkeys}) eq 'CODE') { | |
347 | $keys = $s->{sortkeys}($val); | |
348 | unless (ref($keys) eq 'ARRAY') { | |
349 | carp "Sortkeys subroutine did not return ARRAYREF"; | |
350 | $keys = []; | |
351 | } | |
352 | } | |
353 | else { | |
354 | $keys = [ sort keys %$val ]; | |
355 | } | |
356 | } | |
357 | while (($k, $v) = ! $sortkeys ? (each %$val) : | |
358 | @$keys ? ($key = shift(@$keys), $val->{$key}) : | |
359 | () ) | |
360 | { | |
361 | my $nk = $s->_dump($k, ""); | |
362 | $nk = $1 if !$s->{quotekeys} and $nk =~ /^[\"\']([A-Za-z_]\w*)[\"\']$/; | |
363 | $sname = $mname . '{' . $nk . '}'; | |
364 | $out .= $pad . $ipad . $nk . " => "; | |
365 | ||
366 | # temporarily alter apad | |
367 | $s->{apad} .= (" " x (length($nk) + 4)) if $s->{indent} >= 2; | |
368 | $out .= $s->_dump($val->{$k}, $sname) . ","; | |
369 | $s->{apad} = $lpad if $s->{indent} >= 2; | |
370 | } | |
371 | if (substr($out, -1) eq ',') { | |
372 | chop $out; | |
373 | $out .= $pad . ($s->{xpad} x ($s->{level} - 1)); | |
374 | } | |
375 | $out .= ($name =~ /^\%/) ? ')' : '}'; | |
376 | } | |
377 | elsif ($realtype eq 'CODE') { | |
378 | if ($s->{deparse}) { | |
379 | require B::Deparse; | |
380 | my $sub = 'sub ' . (B::Deparse->new)->coderef2text($val); | |
381 | $pad = $s->{sep} . $s->{pad} . $s->{xpad} . $s->{apad} . ' '; | |
382 | $sub =~ s/\n/$pad/gse; | |
383 | $out .= $sub; | |
384 | } else { | |
385 | $out .= 'sub { "DUMMY" }'; | |
386 | carp "Encountered CODE ref, using dummy placeholder" if $s->{purity}; | |
387 | } | |
388 | } | |
389 | else { | |
390 | croak "Can\'t handle $realtype type."; | |
391 | } | |
392 | ||
393 | if ($realpack) { # we have a blessed ref | |
394 | $out .= ', \'' . $realpack . '\'' . ' )'; | |
395 | $out .= '->' . $s->{toaster} . '()' if $s->{toaster} ne ''; | |
396 | $s->{apad} = $blesspad; | |
397 | } | |
398 | $s->{level}--; | |
399 | ||
400 | } | |
401 | else { # simple scalar | |
402 | ||
403 | my $ref = \$_[1]; | |
404 | # first, catalog the scalar | |
405 | if ($name ne '') { | |
406 | ($id) = ("$ref" =~ /\(([^\(]*)\)$/); | |
407 | if (exists $s->{seen}{$id}) { | |
408 | if ($s->{seen}{$id}[2]) { | |
409 | $out = $s->{seen}{$id}[0]; | |
410 | #warn "[<$out]\n"; | |
411 | return "\${$out}"; | |
412 | } | |
413 | } | |
414 | else { | |
415 | #warn "[>\\$name]\n"; | |
416 | $s->{seen}{$id} = ["\\$name", $ref]; | |
417 | } | |
418 | } | |
419 | if (ref($ref) eq 'GLOB' or "$ref" =~ /=GLOB\([^()]+\)$/) { # glob | |
420 | my $name = substr($val, 1); | |
421 | if ($name =~ /^[A-Za-z_][\w:]*$/) { | |
422 | $name =~ s/^main::/::/; | |
423 | $sname = $name; | |
424 | } | |
425 | else { | |
426 | $sname = $s->_dump($name, ""); | |
427 | $sname = '{' . $sname . '}'; | |
428 | } | |
429 | if ($s->{purity}) { | |
430 | my $k; | |
431 | local ($s->{level}) = 0; | |
432 | for $k (qw(SCALAR ARRAY HASH)) { | |
433 | my $gval = *$val{$k}; | |
434 | next unless defined $gval; | |
435 | next if $k eq "SCALAR" && ! defined $$gval; # always there | |
436 | ||
437 | # _dump can push into @post, so we hold our place using $postlen | |
438 | my $postlen = scalar @post; | |
439 | $post[$postlen] = "\*$sname = "; | |
440 | local ($s->{apad}) = " " x length($post[$postlen]) if $s->{indent} >= 2; | |
441 | $post[$postlen] .= $s->_dump($gval, "\*$sname\{$k\}"); | |
442 | } | |
443 | } | |
444 | $out .= '*' . $sname; | |
445 | } | |
446 | elsif (!defined($val)) { | |
447 | $out .= "undef"; | |
448 | } | |
449 | elsif ($val =~ /^(?:0|-?[1-9]\d{0,8})\z/) { # safe decimal number | |
450 | $out .= $val; | |
451 | } | |
452 | else { # string | |
453 | if ($s->{useqq} or $val =~ tr/\0-\377//c) { | |
454 | # Fall back to qq if there's unicode | |
455 | $out .= qquote($val, $s->{useqq}); | |
456 | } | |
457 | else { | |
458 | $val =~ s/([\\\'])/\\$1/g; | |
459 | $out .= '\'' . $val . '\''; | |
460 | } | |
461 | } | |
462 | } | |
463 | if ($id) { | |
464 | # if we made it this far, $id was added to seen list at current | |
465 | # level, so remove it to get deep copies | |
466 | if ($s->{deepcopy}) { | |
467 | delete($s->{seen}{$id}); | |
468 | } | |
469 | elsif ($name) { | |
470 | $s->{seen}{$id}[2] = 1; | |
471 | } | |
472 | } | |
473 | return $out; | |
474 | } | |
475 | ||
476 | # | |
477 | # non-OO style of earlier version | |
478 | # | |
479 | sub Dumper { | |
480 | return Data::Dumper->Dump([@_]); | |
481 | } | |
482 | ||
483 | # compat stub | |
484 | sub DumperX { | |
485 | return Data::Dumper->Dumpxs([@_], []); | |
486 | } | |
487 | ||
488 | sub Dumpf { return Data::Dumper->Dump(@_) } | |
489 | ||
490 | sub Dumpp { print Data::Dumper->Dump(@_) } | |
491 | ||
492 | # | |
493 | # reset the "seen" cache | |
494 | # | |
495 | sub Reset { | |
496 | my($s) = shift; | |
497 | $s->{seen} = {}; | |
498 | return $s; | |
499 | } | |
500 | ||
501 | sub Indent { | |
502 | my($s, $v) = @_; | |
503 | if (defined($v)) { | |
504 | if ($v == 0) { | |
505 | $s->{xpad} = ""; | |
506 | $s->{sep} = ""; | |
507 | } | |
508 | else { | |
509 | $s->{xpad} = " "; | |
510 | $s->{sep} = "\n"; | |
511 | } | |
512 | $s->{indent} = $v; | |
513 | return $s; | |
514 | } | |
515 | else { | |
516 | return $s->{indent}; | |
517 | } | |
518 | } | |
519 | ||
520 | sub Pad { | |
521 | my($s, $v) = @_; | |
522 | defined($v) ? (($s->{pad} = $v), return $s) : $s->{pad}; | |
523 | } | |
524 | ||
525 | sub Varname { | |
526 | my($s, $v) = @_; | |
527 | defined($v) ? (($s->{varname} = $v), return $s) : $s->{varname}; | |
528 | } | |
529 | ||
530 | sub Purity { | |
531 | my($s, $v) = @_; | |
532 | defined($v) ? (($s->{purity} = $v), return $s) : $s->{purity}; | |
533 | } | |
534 | ||
535 | sub Useqq { | |
536 | my($s, $v) = @_; | |
537 | defined($v) ? (($s->{useqq} = $v), return $s) : $s->{useqq}; | |
538 | } | |
539 | ||
540 | sub Terse { | |
541 | my($s, $v) = @_; | |
542 | defined($v) ? (($s->{terse} = $v), return $s) : $s->{terse}; | |
543 | } | |
544 | ||
545 | sub Freezer { | |
546 | my($s, $v) = @_; | |
547 | defined($v) ? (($s->{freezer} = $v), return $s) : $s->{freezer}; | |
548 | } | |
549 | ||
550 | sub Toaster { | |
551 | my($s, $v) = @_; | |
552 | defined($v) ? (($s->{toaster} = $v), return $s) : $s->{toaster}; | |
553 | } | |
554 | ||
555 | sub Deepcopy { | |
556 | my($s, $v) = @_; | |
557 | defined($v) ? (($s->{deepcopy} = $v), return $s) : $s->{deepcopy}; | |
558 | } | |
559 | ||
560 | sub Quotekeys { | |
561 | my($s, $v) = @_; | |
562 | defined($v) ? (($s->{quotekeys} = $v), return $s) : $s->{quotekeys}; | |
563 | } | |
564 | ||
565 | sub Bless { | |
566 | my($s, $v) = @_; | |
567 | defined($v) ? (($s->{'bless'} = $v), return $s) : $s->{'bless'}; | |
568 | } | |
569 | ||
570 | sub Maxdepth { | |
571 | my($s, $v) = @_; | |
572 | defined($v) ? (($s->{'maxdepth'} = $v), return $s) : $s->{'maxdepth'}; | |
573 | } | |
574 | ||
575 | sub Useperl { | |
576 | my($s, $v) = @_; | |
577 | defined($v) ? (($s->{'useperl'} = $v), return $s) : $s->{'useperl'}; | |
578 | } | |
579 | ||
580 | sub Sortkeys { | |
581 | my($s, $v) = @_; | |
582 | defined($v) ? (($s->{'sortkeys'} = $v), return $s) : $s->{'sortkeys'}; | |
583 | } | |
584 | ||
585 | sub Deparse { | |
586 | my($s, $v) = @_; | |
587 | defined($v) ? (($s->{'deparse'} = $v), return $s) : $s->{'deparse'}; | |
588 | } | |
589 | ||
590 | # used by qquote below | |
591 | my %esc = ( | |
592 | "\a" => "\\a", | |
593 | "\b" => "\\b", | |
594 | "\t" => "\\t", | |
595 | "\n" => "\\n", | |
596 | "\f" => "\\f", | |
597 | "\r" => "\\r", | |
598 | "\e" => "\\e", | |
599 | ); | |
600 | ||
601 | # put a string value in double quotes | |
602 | sub qquote { | |
603 | local($_) = shift; | |
604 | s/([\\\"\@\$])/\\$1/g; | |
605 | my $bytes; { use bytes; $bytes = length } | |
606 | s/([^\x00-\x7f])/'\x{'.sprintf("%x",ord($1)).'}'/ge if $bytes > length; | |
607 | return qq("$_") unless | |
608 | /[^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/; # fast exit | |
609 | ||
610 | my $high = shift || ""; | |
611 | s/([\a\b\t\n\f\r\e])/$esc{$1}/g; | |
612 | ||
613 | if (ord('^')==94) { # ascii | |
614 | # no need for 3 digits in escape for these | |
615 | s/([\0-\037])(?!\d)/'\\'.sprintf('%o',ord($1))/eg; | |
616 | s/([\0-\037\177])/'\\'.sprintf('%03o',ord($1))/eg; | |
617 | # all but last branch below not supported --BEHAVIOR SUBJECT TO CHANGE-- | |
618 | if ($high eq "iso8859") { | |
619 | s/([\200-\240])/'\\'.sprintf('%o',ord($1))/eg; | |
620 | } elsif ($high eq "utf8") { | |
621 | # use utf8; | |
622 | # $str =~ s/([^\040-\176])/sprintf "\\x{%04x}", ord($1)/ge; | |
623 | } elsif ($high eq "8bit") { | |
624 | # leave it as it is | |
625 | } else { | |
626 | s/([\200-\377])/'\\'.sprintf('%03o',ord($1))/eg; | |
627 | s/([^\040-\176])/sprintf "\\x{%04x}", ord($1)/ge; | |
628 | } | |
629 | } | |
630 | else { # ebcdic | |
631 | s{([^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~])(?!\d)} | |
632 | {my $v = ord($1); '\\'.sprintf(($v <= 037 ? '%o' : '%03o'), $v)}eg; | |
633 | s{([^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~])} | |
634 | {'\\'.sprintf('%03o',ord($1))}eg; | |
635 | } | |
636 | ||
637 | return qq("$_"); | |
638 | } | |
639 | ||
640 | 1; | |
641 | __END__ | |
642 | ||
643 | =head1 NAME | |
644 | ||
645 | Data::Dumper - stringified perl data structures, suitable for both printing and C<eval> | |
646 | ||
647 | =head1 SYNOPSIS | |
648 | ||
649 | use Data::Dumper; | |
650 | ||
651 | # simple procedural interface | |
652 | print Dumper($foo, $bar); | |
653 | ||
654 | # extended usage with names | |
655 | print Data::Dumper->Dump([$foo, $bar], [qw(foo *ary)]); | |
656 | ||
657 | # configuration variables | |
658 | { | |
659 | local $Data::Dump::Purity = 1; | |
660 | eval Data::Dumper->Dump([$foo, $bar], [qw(foo *ary)]); | |
661 | } | |
662 | ||
663 | # OO usage | |
664 | $d = Data::Dumper->new([$foo, $bar], [qw(foo *ary)]); | |
665 | ... | |
666 | print $d->Dump; | |
667 | ... | |
668 | $d->Purity(1)->Terse(1)->Deepcopy(1); | |
669 | eval $d->Dump; | |
670 | ||
671 | ||
672 | =head1 DESCRIPTION | |
673 | ||
674 | Given a list of scalars or reference variables, writes out their contents in | |
675 | perl syntax. The references can also be objects. The contents of each | |
676 | variable is output in a single Perl statement. Handles self-referential | |
677 | structures correctly. | |
678 | ||
679 | The return value can be C<eval>ed to get back an identical copy of the | |
680 | original reference structure. | |
681 | ||
682 | Any references that are the same as one of those passed in will be named | |
683 | C<$VAR>I<n> (where I<n> is a numeric suffix), and other duplicate references | |
684 | to substructures within C<$VAR>I<n> will be appropriately labeled using arrow | |
685 | notation. You can specify names for individual values to be dumped if you | |
686 | use the C<Dump()> method, or you can change the default C<$VAR> prefix to | |
687 | something else. See C<$Data::Dumper::Varname> and C<$Data::Dumper::Terse> | |
688 | below. | |
689 | ||
690 | The default output of self-referential structures can be C<eval>ed, but the | |
691 | nested references to C<$VAR>I<n> will be undefined, since a recursive | |
692 | structure cannot be constructed using one Perl statement. You should set the | |
693 | C<Purity> flag to 1 to get additional statements that will correctly fill in | |
694 | these references. | |
695 | ||
696 | In the extended usage form, the references to be dumped can be given | |
697 | user-specified names. If a name begins with a C<*>, the output will | |
698 | describe the dereferenced type of the supplied reference for hashes and | |
699 | arrays, and coderefs. Output of names will be avoided where possible if | |
700 | the C<Terse> flag is set. | |
701 | ||
702 | In many cases, methods that are used to set the internal state of the | |
703 | object will return the object itself, so method calls can be conveniently | |
704 | chained together. | |
705 | ||
706 | Several styles of output are possible, all controlled by setting | |
707 | the C<Indent> flag. See L<Configuration Variables or Methods> below | |
708 | for details. | |
709 | ||
710 | ||
711 | =head2 Methods | |
712 | ||
713 | =over 4 | |
714 | ||
715 | =item I<PACKAGE>->new(I<ARRAYREF [>, I<ARRAYREF]>) | |
716 | ||
717 | Returns a newly created C<Data::Dumper> object. The first argument is an | |
718 | anonymous array of values to be dumped. The optional second argument is an | |
719 | anonymous array of names for the values. The names need not have a leading | |
720 | C<$> sign, and must be comprised of alphanumeric characters. You can begin | |
721 | a name with a C<*> to specify that the dereferenced type must be dumped | |
722 | instead of the reference itself, for ARRAY and HASH references. | |
723 | ||
724 | The prefix specified by C<$Data::Dumper::Varname> will be used with a | |
725 | numeric suffix if the name for a value is undefined. | |
726 | ||
727 | Data::Dumper will catalog all references encountered while dumping the | |
728 | values. Cross-references (in the form of names of substructures in perl | |
729 | syntax) will be inserted at all possible points, preserving any structural | |
730 | interdependencies in the original set of values. Structure traversal is | |
731 | depth-first, and proceeds in order from the first supplied value to | |
732 | the last. | |
733 | ||
734 | =item I<$OBJ>->Dump I<or> I<PACKAGE>->Dump(I<ARRAYREF [>, I<ARRAYREF]>) | |
735 | ||
736 | Returns the stringified form of the values stored in the object (preserving | |
737 | the order in which they were supplied to C<new>), subject to the | |
738 | configuration options below. In a list context, it returns a list | |
739 | of strings corresponding to the supplied values. | |
740 | ||
741 | The second form, for convenience, simply calls the C<new> method on its | |
742 | arguments before dumping the object immediately. | |
743 | ||
744 | =item I<$OBJ>->Seen(I<[HASHREF]>) | |
745 | ||
746 | Queries or adds to the internal table of already encountered references. | |
747 | You must use C<Reset> to explicitly clear the table if needed. Such | |
748 | references are not dumped; instead, their names are inserted wherever they | |
749 | are encountered subsequently. This is useful especially for properly | |
750 | dumping subroutine references. | |
751 | ||
752 | Expects an anonymous hash of name => value pairs. Same rules apply for names | |
753 | as in C<new>. If no argument is supplied, will return the "seen" list of | |
754 | name => value pairs, in a list context. Otherwise, returns the object | |
755 | itself. | |
756 | ||
757 | =item I<$OBJ>->Values(I<[ARRAYREF]>) | |
758 | ||
759 | Queries or replaces the internal array of values that will be dumped. | |
760 | When called without arguments, returns the values. Otherwise, returns the | |
761 | object itself. | |
762 | ||
763 | =item I<$OBJ>->Names(I<[ARRAYREF]>) | |
764 | ||
765 | Queries or replaces the internal array of user supplied names for the values | |
766 | that will be dumped. When called without arguments, returns the names. | |
767 | Otherwise, returns the object itself. | |
768 | ||
769 | =item I<$OBJ>->Reset | |
770 | ||
771 | Clears the internal table of "seen" references and returns the object | |
772 | itself. | |
773 | ||
774 | =back | |
775 | ||
776 | =head2 Functions | |
777 | ||
778 | =over 4 | |
779 | ||
780 | =item Dumper(I<LIST>) | |
781 | ||
782 | Returns the stringified form of the values in the list, subject to the | |
783 | configuration options below. The values will be named C<$VAR>I<n> in the | |
784 | output, where I<n> is a numeric suffix. Will return a list of strings | |
785 | in a list context. | |
786 | ||
787 | =back | |
788 | ||
789 | =head2 Configuration Variables or Methods | |
790 | ||
791 | Several configuration variables can be used to control the kind of output | |
792 | generated when using the procedural interface. These variables are usually | |
793 | C<local>ized in a block so that other parts of the code are not affected by | |
794 | the change. | |
795 | ||
796 | These variables determine the default state of the object created by calling | |
797 | the C<new> method, but cannot be used to alter the state of the object | |
798 | thereafter. The equivalent method names should be used instead to query | |
799 | or set the internal state of the object. | |
800 | ||
801 | The method forms return the object itself when called with arguments, | |
802 | so that they can be chained together nicely. | |
803 | ||
804 | =over 4 | |
805 | ||
806 | =item $Data::Dumper::Indent I<or> I<$OBJ>->Indent(I<[NEWVAL]>) | |
807 | ||
808 | Controls the style of indentation. It can be set to 0, 1, 2 or 3. Style 0 | |
809 | spews output without any newlines, indentation, or spaces between list | |
810 | items. It is the most compact format possible that can still be called | |
811 | valid perl. Style 1 outputs a readable form with newlines but no fancy | |
812 | indentation (each level in the structure is simply indented by a fixed | |
813 | amount of whitespace). Style 2 (the default) outputs a very readable form | |
814 | which takes into account the length of hash keys (so the hash value lines | |
815 | up). Style 3 is like style 2, but also annotates the elements of arrays | |
816 | with their index (but the comment is on its own line, so array output | |
817 | consumes twice the number of lines). Style 2 is the default. | |
818 | ||
819 | =item $Data::Dumper::Purity I<or> I<$OBJ>->Purity(I<[NEWVAL]>) | |
820 | ||
821 | Controls the degree to which the output can be C<eval>ed to recreate the | |
822 | supplied reference structures. Setting it to 1 will output additional perl | |
823 | statements that will correctly recreate nested references. The default is | |
824 | 0. | |
825 | ||
826 | =item $Data::Dumper::Pad I<or> I<$OBJ>->Pad(I<[NEWVAL]>) | |
827 | ||
828 | Specifies the string that will be prefixed to every line of the output. | |
829 | Empty string by default. | |
830 | ||
831 | =item $Data::Dumper::Varname I<or> I<$OBJ>->Varname(I<[NEWVAL]>) | |
832 | ||
833 | Contains the prefix to use for tagging variable names in the output. The | |
834 | default is "VAR". | |
835 | ||
836 | =item $Data::Dumper::Useqq I<or> I<$OBJ>->Useqq(I<[NEWVAL]>) | |
837 | ||
838 | When set, enables the use of double quotes for representing string values. | |
839 | Whitespace other than space will be represented as C<[\n\t\r]>, "unsafe" | |
840 | characters will be backslashed, and unprintable characters will be output as | |
841 | quoted octal integers. Since setting this variable imposes a performance | |
842 | penalty, the default is 0. C<Dump()> will run slower if this flag is set, | |
843 | since the fast XSUB implementation doesn't support it yet. | |
844 | ||
845 | =item $Data::Dumper::Terse I<or> I<$OBJ>->Terse(I<[NEWVAL]>) | |
846 | ||
847 | When set, Data::Dumper will emit single, non-self-referential values as | |
848 | atoms/terms rather than statements. This means that the C<$VAR>I<n> names | |
849 | will be avoided where possible, but be advised that such output may not | |
850 | always be parseable by C<eval>. | |
851 | ||
852 | =item $Data::Dumper::Freezer I<or> $I<OBJ>->Freezer(I<[NEWVAL]>) | |
853 | ||
854 | Can be set to a method name, or to an empty string to disable the feature. | |
855 | Data::Dumper will invoke that method via the object before attempting to | |
856 | stringify it. This method can alter the contents of the object (if, for | |
857 | instance, it contains data allocated from C), and even rebless it in a | |
858 | different package. The client is responsible for making sure the specified | |
859 | method can be called via the object, and that the object ends up containing | |
860 | only perl data types after the method has been called. Defaults to an empty | |
861 | string. | |
862 | ||
863 | =item $Data::Dumper::Toaster I<or> $I<OBJ>->Toaster(I<[NEWVAL]>) | |
864 | ||
865 | Can be set to a method name, or to an empty string to disable the feature. | |
866 | Data::Dumper will emit a method call for any objects that are to be dumped | |
867 | using the syntax C<bless(DATA, CLASS)-E<gt>METHOD()>. Note that this means that | |
868 | the method specified will have to perform any modifications required on the | |
869 | object (like creating new state within it, and/or reblessing it in a | |
870 | different package) and then return it. The client is responsible for making | |
871 | sure the method can be called via the object, and that it returns a valid | |
872 | object. Defaults to an empty string. | |
873 | ||
874 | =item $Data::Dumper::Deepcopy I<or> $I<OBJ>->Deepcopy(I<[NEWVAL]>) | |
875 | ||
876 | Can be set to a boolean value to enable deep copies of structures. | |
877 | Cross-referencing will then only be done when absolutely essential | |
878 | (i.e., to break reference cycles). Default is 0. | |
879 | ||
880 | =item $Data::Dumper::Quotekeys I<or> $I<OBJ>->Quotekeys(I<[NEWVAL]>) | |
881 | ||
882 | Can be set to a boolean value to control whether hash keys are quoted. | |
883 | A false value will avoid quoting hash keys when it looks like a simple | |
884 | string. Default is 1, which will always enclose hash keys in quotes. | |
885 | ||
886 | =item $Data::Dumper::Bless I<or> $I<OBJ>->Bless(I<[NEWVAL]>) | |
887 | ||
888 | Can be set to a string that specifies an alternative to the C<bless> | |
889 | builtin operator used to create objects. A function with the specified | |
890 | name should exist, and should accept the same arguments as the builtin. | |
891 | Default is C<bless>. | |
892 | ||
893 | =item $Data::Dumper::Maxdepth I<or> $I<OBJ>->Maxdepth(I<[NEWVAL]>) | |
894 | ||
895 | Can be set to a positive integer that specifies the depth beyond which | |
896 | which we don't venture into a structure. Has no effect when | |
897 | C<Data::Dumper::Purity> is set. (Useful in debugger when we often don't | |
898 | want to see more than enough). Default is 0, which means there is | |
899 | no maximum depth. | |
900 | ||
901 | =item $Data::Dumper::Useperl I<or> $I<OBJ>->Useperl(I<[NEWVAL]>) | |
902 | ||
903 | Can be set to a boolean value which controls whether the pure Perl | |
904 | implementation of C<Data::Dumper> is used. The C<Data::Dumper> module is | |
905 | a dual implementation, with almost all functionality written in both | |
906 | pure Perl and also in XS ('C'). Since the XS version is much faster, it | |
907 | will always be used if possible. This option lets you override the | |
908 | default behavior, usually for testing purposes only. Default is 0, which | |
909 | means the XS implementation will be used if possible. | |
910 | ||
911 | =item $Data::Dumper::Sortkeys I<or> $I<OBJ>->Sortkeys(I<[NEWVAL]>) | |
912 | ||
913 | Can be set to a boolean value to control whether hash keys are dumped in | |
914 | sorted order. A true value will cause the keys of all hashes to be | |
915 | dumped in Perl's default sort order. Can also be set to a subroutine | |
916 | reference which will be called for each hash that is dumped. In this | |
917 | case C<Data::Dumper> will call the subroutine once for each hash, | |
918 | passing it the reference of the hash. The purpose of the subroutine is | |
919 | to return a reference to an array of the keys that will be dumped, in | |
920 | the order that they should be dumped. Using this feature, you can | |
921 | control both the order of the keys, and which keys are actually used. In | |
922 | other words, this subroutine acts as a filter by which you can exclude | |
923 | certain keys from being dumped. Default is 0, which means that hash keys | |
924 | are not sorted. | |
925 | ||
926 | =item $Data::Dumper::Deparse I<or> $I<OBJ>->Deparse(I<[NEWVAL]>) | |
927 | ||
928 | Can be set to a boolean value to control whether code references are | |
929 | turned into perl source code. If set to a true value, C<B::Deparse> | |
930 | will be used to get the source of the code reference. Using this option | |
931 | will force using the Perl implementation of the dumper, since the fast | |
932 | XSUB implementation doesn't support it. | |
933 | ||
934 | Caution : use this option only if you know that your coderefs will be | |
935 | properly reconstructed by C<B::Deparse>. | |
936 | ||
937 | =back | |
938 | ||
939 | =head2 Exports | |
940 | ||
941 | =over 4 | |
942 | ||
943 | =item Dumper | |
944 | ||
945 | =back | |
946 | ||
947 | =head1 EXAMPLES | |
948 | ||
949 | Run these code snippets to get a quick feel for the behavior of this | |
950 | module. When you are through with these examples, you may want to | |
951 | add or change the various configuration variables described above, | |
952 | to see their behavior. (See the testsuite in the Data::Dumper | |
953 | distribution for more examples.) | |
954 | ||
955 | ||
956 | use Data::Dumper; | |
957 | ||
958 | package Foo; | |
959 | sub new {bless {'a' => 1, 'b' => sub { return "foo" }}, $_[0]}; | |
960 | ||
961 | package Fuz; # a weird REF-REF-SCALAR object | |
962 | sub new {bless \($_ = \ 'fu\'z'), $_[0]}; | |
963 | ||
964 | package main; | |
965 | $foo = Foo->new; | |
966 | $fuz = Fuz->new; | |
967 | $boo = [ 1, [], "abcd", \*foo, | |
968 | {1 => 'a', 023 => 'b', 0x45 => 'c'}, | |
969 | \\"p\q\'r", $foo, $fuz]; | |
970 | ||
971 | ######## | |
972 | # simple usage | |
973 | ######## | |
974 | ||
975 | $bar = eval(Dumper($boo)); | |
976 | print($@) if $@; | |
977 | print Dumper($boo), Dumper($bar); # pretty print (no array indices) | |
978 | ||
979 | $Data::Dumper::Terse = 1; # don't output names where feasible | |
980 | $Data::Dumper::Indent = 0; # turn off all pretty print | |
981 | print Dumper($boo), "\n"; | |
982 | ||
983 | $Data::Dumper::Indent = 1; # mild pretty print | |
984 | print Dumper($boo); | |
985 | ||
986 | $Data::Dumper::Indent = 3; # pretty print with array indices | |
987 | print Dumper($boo); | |
988 | ||
989 | $Data::Dumper::Useqq = 1; # print strings in double quotes | |
990 | print Dumper($boo); | |
991 | ||
992 | ||
993 | ######## | |
994 | # recursive structures | |
995 | ######## | |
996 | ||
997 | @c = ('c'); | |
998 | $c = \@c; | |
999 | $b = {}; | |
1000 | $a = [1, $b, $c]; | |
1001 | $b->{a} = $a; | |
1002 | $b->{b} = $a->[1]; | |
1003 | $b->{c} = $a->[2]; | |
1004 | print Data::Dumper->Dump([$a,$b,$c], [qw(a b c)]); | |
1005 | ||
1006 | ||
1007 | $Data::Dumper::Purity = 1; # fill in the holes for eval | |
1008 | print Data::Dumper->Dump([$a, $b], [qw(*a b)]); # print as @a | |
1009 | print Data::Dumper->Dump([$b, $a], [qw(*b a)]); # print as %b | |
1010 | ||
1011 | ||
1012 | $Data::Dumper::Deepcopy = 1; # avoid cross-refs | |
1013 | print Data::Dumper->Dump([$b, $a], [qw(*b a)]); | |
1014 | ||
1015 | ||
1016 | $Data::Dumper::Purity = 0; # avoid cross-refs | |
1017 | print Data::Dumper->Dump([$b, $a], [qw(*b a)]); | |
1018 | ||
1019 | ######## | |
1020 | # deep structures | |
1021 | ######## | |
1022 | ||
1023 | $a = "pearl"; | |
1024 | $b = [ $a ]; | |
1025 | $c = { 'b' => $b }; | |
1026 | $d = [ $c ]; | |
1027 | $e = { 'd' => $d }; | |
1028 | $f = { 'e' => $e }; | |
1029 | print Data::Dumper->Dump([$f], [qw(f)]); | |
1030 | ||
1031 | $Data::Dumper::Maxdepth = 3; # no deeper than 3 refs down | |
1032 | print Data::Dumper->Dump([$f], [qw(f)]); | |
1033 | ||
1034 | ||
1035 | ######## | |
1036 | # object-oriented usage | |
1037 | ######## | |
1038 | ||
1039 | $d = Data::Dumper->new([$a,$b], [qw(a b)]); | |
1040 | $d->Seen({'*c' => $c}); # stash a ref without printing it | |
1041 | $d->Indent(3); | |
1042 | print $d->Dump; | |
1043 | $d->Reset->Purity(0); # empty the seen cache | |
1044 | print join "----\n", $d->Dump; | |
1045 | ||
1046 | ||
1047 | ######## | |
1048 | # persistence | |
1049 | ######## | |
1050 | ||
1051 | package Foo; | |
1052 | sub new { bless { state => 'awake' }, shift } | |
1053 | sub Freeze { | |
1054 | my $s = shift; | |
1055 | print STDERR "preparing to sleep\n"; | |
1056 | $s->{state} = 'asleep'; | |
1057 | return bless $s, 'Foo::ZZZ'; | |
1058 | } | |
1059 | ||
1060 | package Foo::ZZZ; | |
1061 | sub Thaw { | |
1062 | my $s = shift; | |
1063 | print STDERR "waking up\n"; | |
1064 | $s->{state} = 'awake'; | |
1065 | return bless $s, 'Foo'; | |
1066 | } | |
1067 | ||
1068 | package Foo; | |
1069 | use Data::Dumper; | |
1070 | $a = Foo->new; | |
1071 | $b = Data::Dumper->new([$a], ['c']); | |
1072 | $b->Freezer('Freeze'); | |
1073 | $b->Toaster('Thaw'); | |
1074 | $c = $b->Dump; | |
1075 | print $c; | |
1076 | $d = eval $c; | |
1077 | print Data::Dumper->Dump([$d], ['d']); | |
1078 | ||
1079 | ||
1080 | ######## | |
1081 | # symbol substitution (useful for recreating CODE refs) | |
1082 | ######## | |
1083 | ||
1084 | sub foo { print "foo speaking\n" } | |
1085 | *other = \&foo; | |
1086 | $bar = [ \&other ]; | |
1087 | $d = Data::Dumper->new([\&other,$bar],['*other','bar']); | |
1088 | $d->Seen({ '*foo' => \&foo }); | |
1089 | print $d->Dump; | |
1090 | ||
1091 | ||
1092 | ######## | |
1093 | # sorting and filtering hash keys | |
1094 | ######## | |
1095 | ||
1096 | $Data::Dumper::Sortkeys = \&my_filter; | |
1097 | my $foo = { map { (ord, "$_$_$_") } 'I'..'Q' }; | |
1098 | my $bar = { %$foo }; | |
1099 | my $baz = { reverse %$foo }; | |
1100 | print Dumper [ $foo, $bar, $baz ]; | |
1101 | ||
1102 | sub my_filter { | |
1103 | my ($hash) = @_; | |
1104 | # return an array ref containing the hash keys to dump | |
1105 | # in the order that you want them to be dumped | |
1106 | return [ | |
1107 | # Sort the keys of %$foo in reverse numeric order | |
1108 | $hash eq $foo ? (sort {$b <=> $a} keys %$hash) : | |
1109 | # Only dump the odd number keys of %$bar | |
1110 | $hash eq $bar ? (grep {$_ % 2} keys %$hash) : | |
1111 | # Sort keys in default order for all other hashes | |
1112 | (sort keys %$hash) | |
1113 | ]; | |
1114 | } | |
1115 | ||
1116 | =head1 BUGS | |
1117 | ||
1118 | Due to limitations of Perl subroutine call semantics, you cannot pass an | |
1119 | array or hash. Prepend it with a C<\> to pass its reference instead. This | |
1120 | will be remedied in time, now that Perl has subroutine prototypes. | |
1121 | For now, you need to use the extended usage form, and prepend the | |
1122 | name with a C<*> to output it as a hash or array. | |
1123 | ||
1124 | C<Data::Dumper> cheats with CODE references. If a code reference is | |
1125 | encountered in the structure being processed (and if you haven't set | |
1126 | the C<Deparse> flag), an anonymous subroutine that | |
1127 | contains the string '"DUMMY"' will be inserted in its place, and a warning | |
1128 | will be printed if C<Purity> is set. You can C<eval> the result, but bear | |
1129 | in mind that the anonymous sub that gets created is just a placeholder. | |
1130 | Someday, perl will have a switch to cache-on-demand the string | |
1131 | representation of a compiled piece of code, I hope. If you have prior | |
1132 | knowledge of all the code refs that your data structures are likely | |
1133 | to have, you can use the C<Seen> method to pre-seed the internal reference | |
1134 | table and make the dumped output point to them, instead. See L<EXAMPLES> | |
1135 | above. | |
1136 | ||
1137 | The C<Useqq> and C<Deparse> flags makes Dump() run slower, since the | |
1138 | XSUB implementation does not support them. | |
1139 | ||
1140 | SCALAR objects have the weirdest looking C<bless> workaround. | |
1141 | ||
1142 | ||
1143 | =head1 AUTHOR | |
1144 | ||
1145 | Gurusamy Sarathy gsar@activestate.com | |
1146 | ||
1147 | Copyright (c) 1996-98 Gurusamy Sarathy. All rights reserved. | |
1148 | This program is free software; you can redistribute it and/or | |
1149 | modify it under the same terms as Perl itself. | |
1150 | ||
1151 | ||
1152 | =head1 VERSION | |
1153 | ||
1154 | Version 2.12 (unreleased) | |
1155 | ||
1156 | =head1 SEE ALSO | |
1157 | ||
1158 | perl(1) | |
1159 | ||
1160 | =cut |