package Data::Dumper;
-$VERSION = '2.101';
+$VERSION = '2.121_08';
#$| = 1;
-require 5.005_64;
+use 5.006_001;
require Exporter;
-use XSLoader ();
require overload;
use Carp;
-@ISA = qw(Exporter);
-@EXPORT = qw(Dumper);
-@EXPORT_OK = qw(DumperX);
+BEGIN {
+ @ISA = qw(Exporter);
+ @EXPORT = qw(Dumper);
+ @EXPORT_OK = qw(DumperX);
+
+ # if run under miniperl, or otherwise lacking dynamic loading,
+ # XSLoader should be attempted to load, or the pure perl flag
+ # toggled on load failure.
+ eval {
+ require XSLoader;
+ };
+ $Useperl = 1 if $@;
+}
-XSLoader::load 'Data::Dumper';
+XSLoader::load( 'Data::Dumper' ) unless $Useperl;
# module vars and their defaults
-$Indent = 2 unless defined $Indent;
-$Purity = 0 unless defined $Purity;
-$Pad = "" unless defined $Pad;
-$Varname = "VAR" unless defined $Varname;
-$Useqq = 0 unless defined $Useqq;
-$Terse = 0 unless defined $Terse;
-$Freezer = "" unless defined $Freezer;
-$Toaster = "" unless defined $Toaster;
-$Deepcopy = 0 unless defined $Deepcopy;
-$Quotekeys = 1 unless defined $Quotekeys;
-$Bless = "bless" unless defined $Bless;
-#$Expdepth = 0 unless defined $Expdepth;
-$Maxdepth = 0 unless defined $Maxdepth;
+$Indent = 2 unless defined $Indent;
+$Purity = 0 unless defined $Purity;
+$Pad = "" unless defined $Pad;
+$Varname = "VAR" unless defined $Varname;
+$Useqq = 0 unless defined $Useqq;
+$Terse = 0 unless defined $Terse;
+$Freezer = "" unless defined $Freezer;
+$Toaster = "" unless defined $Toaster;
+$Deepcopy = 0 unless defined $Deepcopy;
+$Quotekeys = 1 unless defined $Quotekeys;
+$Bless = "bless" unless defined $Bless;
+#$Expdepth = 0 unless defined $Expdepth;
+$Maxdepth = 0 unless defined $Maxdepth;
+$Pair = ' => ' unless defined $Pair;
+$Useperl = 0 unless defined $Useperl;
+$Sortkeys = 0 unless defined $Sortkeys;
+$Deparse = 0 unless defined $Deparse;
#
# expects an arrayref of values to be dumped.
xpad => "", # padding-per-level
apad => "", # added padding for hash keys n such
sep => "", # list separator
+ pair => $Pair, # hash key/value separator: defaults to ' => '
seen => {}, # local (nested) refs (id => [name, val])
todump => $v, # values to dump []
names => $n, # optional names for values []
'bless' => $Bless, # keyword to use for "bless"
# expdepth => $Expdepth, # cutoff depth for explicit dumping
maxdepth => $Maxdepth, # depth beyond which we give up
+ useperl => $Useperl, # use the pure Perl implementation
+ sortkeys => $Sortkeys, # flag or filter for sorting hash keys
+ deparse => $Deparse, # use B::Deparse for coderefs
};
if ($Indent > 0) {
return bless($s, $c);
}
+sub init_refaddr_format {
+ require Config;
+ my $f = $Config::Config{uvxformat};
+ $f =~ tr/"//d;
+ our $refaddr_format = "0x%" . $f;
+}
+
+sub format_refaddr {
+ require Scalar::Util;
+ sprintf our $refaddr_format, Scalar::Util::refaddr(shift);
+}
+
#
# add-to or query the table of already seen references
#
my($k, $v, $id);
while (($k, $v) = each %$g) {
if (defined $v and ref $v) {
- ($id) = (overload::StrVal($v) =~ /\((.*)\)$/);
+ $id = format_refaddr($v);
if ($k =~ /^[*](.*)$/) {
$k = (ref $v eq 'ARRAY') ? ( "\\\@" . $1 ) :
(ref $v eq 'HASH') ? ( "\\\%" . $1 ) :
sub DESTROY {}
+sub Dump {
+ return &Dumpxs
+ unless $Data::Dumper::Useperl || (ref($_[0]) && $_[0]->{useperl}) ||
+ $Data::Dumper::Useqq || (ref($_[0]) && $_[0]->{useqq}) ||
+ $Data::Dumper::Deparse || (ref($_[0]) && $_[0]->{deparse});
+ return &Dumpperl;
+}
+
#
# dump the refs in the current dumper object.
# expects same args as new() if called via package name.
#
-sub Dump {
+sub Dumpperl {
my($s) = shift;
my(@out, $val, $name);
my($i) = 0;
local(@post);
+ init_refaddr_format();
$s = $s->new(@_) unless ref $s;
#
# twist, toil and turn;
# and recurse, of course.
+# sometimes sordidly;
+# and curse if no recourse.
#
sub _dump {
my($s, $val, $name) = @_;
if ($type) {
- # prep it, if it looks like an object
- if (my $freezer = $s->{freezer}) {
- $val->$freezer() if UNIVERSAL::can($val, $freezer);
+ # Call the freezer method if it's specified and the object has the
+ # method. Trap errors and warn() instead of die()ing, like the XS
+ # implementation.
+ my $freezer = $s->{freezer};
+ if ($freezer and UNIVERSAL::can($val, $freezer)) {
+ eval { $val->$freezer() };
+ warn "WARNING(Freezer method call failed): $@" if $@;
}
- ($realpack, $realtype, $id) =
- (overload::StrVal($val) =~ /^(?:(.*)\=)?([^=]*)\(([^\(]*)\)$/);
+ require Scalar::Util;
+ $realpack = Scalar::Util::blessed($val);
+ $realtype = $realpack ? Scalar::Util::reftype($val) : ref $val;
+ $id = format_refaddr($val);
# if it has a name, we need to either look it up, or keep a tab
# on it so we know when we hit it later
$s->{level}++;
$ipad = $s->{xpad} x $s->{level};
-
- if ($realtype eq 'SCALAR') {
+ if ($realtype eq 'SCALAR' || $realtype eq 'REF') {
if ($realpack) {
$out .= 'do{\\(my $o = ' . $s->_dump($$val, "\${$name}") . ')}';
}
$out .= ($name =~ /^\@/) ? ')' : ']';
}
elsif ($realtype eq 'HASH') {
- my($k, $v, $pad, $lpad, $mname);
+ my($k, $v, $pad, $lpad, $mname, $pair);
$out .= ($name =~ /^\%/) ? '(' : '{';
$pad = $s->{sep} . $s->{pad} . $s->{apad};
$lpad = $s->{apad};
+ $pair = $s->{pair};
($name =~ /^\%(.*)$/) ? ($mname = "\$" . $1) :
# omit -> if $foo->[0]->{bar}, but not ${$foo->[0]}->{bar}
($name =~ /^\\?[\%\@\*\$][^{].*[]}]$/) ? ($mname = $name) :
($mname = $name . '->');
$mname .= '->' if $mname =~ /^\*.+\{[A-Z]+\}$/;
- while (($k, $v) = each %$val) {
+ my ($sortkeys, $keys, $key) = ("$s->{sortkeys}");
+ if ($sortkeys) {
+ if (ref($s->{sortkeys}) eq 'CODE') {
+ $keys = $s->{sortkeys}($val);
+ unless (ref($keys) eq 'ARRAY') {
+ carp "Sortkeys subroutine did not return ARRAYREF";
+ $keys = [];
+ }
+ }
+ else {
+ $keys = [ sort keys %$val ];
+ }
+ }
+ while (($k, $v) = ! $sortkeys ? (each %$val) :
+ @$keys ? ($key = shift(@$keys), $val->{$key}) :
+ () )
+ {
my $nk = $s->_dump($k, "");
$nk = $1 if !$s->{quotekeys} and $nk =~ /^[\"\']([A-Za-z_]\w*)[\"\']$/;
$sname = $mname . '{' . $nk . '}';
- $out .= $pad . $ipad . $nk . " => ";
+ $out .= $pad . $ipad . $nk . $pair;
# temporarily alter apad
$s->{apad} .= (" " x (length($nk) + 4)) if $s->{indent} >= 2;
$out .= ($name =~ /^\%/) ? ')' : '}';
}
elsif ($realtype eq 'CODE') {
- $out .= 'sub { "DUMMY" }';
- carp "Encountered CODE ref, using dummy placeholder" if $s->{purity};
+ if ($s->{deparse}) {
+ require B::Deparse;
+ my $sub = 'sub ' . (B::Deparse->new)->coderef2text($val);
+ $pad = $s->{sep} . $s->{pad} . $s->{apad} . $s->{xpad} x ($s->{level} - 1);
+ $sub =~ s/\n/$pad/gse;
+ $out .= $sub;
+ } else {
+ $out .= 'sub { "DUMMY" }';
+ carp "Encountered CODE ref, using dummy placeholder" if $s->{purity};
+ }
}
else {
croak "Can\'t handle $realtype type.";
my $ref = \$_[1];
# first, catalog the scalar
if ($name ne '') {
- ($id) = ("$ref" =~ /\(([^\(]*)\)$/);
+ $id = format_refaddr($ref);
if (exists $s->{seen}{$id}) {
if ($s->{seen}{$id}[2]) {
$out = $s->{seen}{$id}[0];
elsif (!defined($val)) {
$out .= "undef";
}
- elsif ($val =~ /^(?:0|-?[1-9]\d{0,8})$/) { # safe decimal number
+ elsif ($val =~ /^(?:0|-?[1-9]\d{0,8})\z/) { # safe decimal number
$out .= $val;
}
else { # string
- if ($s->{useqq}) {
+ if ($s->{useqq} or $val =~ tr/\0-\377//c) {
+ # Fall back to qq if there's unicode
$out .= qquote($val, $s->{useqq});
}
else {
return Data::Dumper->Dump([@_]);
}
-#
-# same, only calls the XS version
-#
+# compat stub
sub DumperX {
return Data::Dumper->Dumpxs([@_], []);
}
}
}
+sub Pair {
+ my($s, $v) = @_;
+ defined($v) ? (($s->{pair} = $v), return $s) : $s->{pair};
+}
+
sub Pad {
my($s, $v) = @_;
defined($v) ? (($s->{pad} = $v), return $s) : $s->{pad};
defined($v) ? (($s->{'maxdepth'} = $v), return $s) : $s->{'maxdepth'};
}
+sub Useperl {
+ my($s, $v) = @_;
+ defined($v) ? (($s->{'useperl'} = $v), return $s) : $s->{'useperl'};
+}
+
+sub Sortkeys {
+ my($s, $v) = @_;
+ defined($v) ? (($s->{'sortkeys'} = $v), return $s) : $s->{'sortkeys'};
+}
+
+sub Deparse {
+ my($s, $v) = @_;
+ defined($v) ? (($s->{'deparse'} = $v), return $s) : $s->{'deparse'};
+}
# used by qquote below
my %esc = (
sub qquote {
local($_) = shift;
s/([\\\"\@\$])/\\$1/g;
+ my $bytes; { use bytes; $bytes = length }
+ s/([^\x00-\x7f])/'\x{'.sprintf("%x",ord($1)).'}'/ge if $bytes > length;
return qq("$_") unless
/[^ !"\#\$%&'()*+,\-.\/0-9:;<=>?\@A-Z[\\\]^_`a-z{|}~]/; # fast exit
# leave it as it is
} else {
s/([\200-\377])/'\\'.sprintf('%03o',ord($1))/eg;
+ s/([^\040-\176])/sprintf "\\x{%04x}", ord($1)/ge;
}
}
else { # ebcdic
return qq("$_");
}
+# helper sub to sort hash keys in Perl < 5.8.0 where we don't have
+# access to sortsv() from XS
+sub _sortkeys { [ sort keys %{$_[0]} ] }
+
1;
__END__
Data::Dumper - stringified perl data structures, suitable for both printing and C<eval>
-
=head1 SYNOPSIS
use Data::Dumper;
# configuration variables
{
- local $Data::Dump::Purity = 1;
+ local $Data::Dumper::Purity = 1;
eval Data::Dumper->Dump([$foo, $bar], [qw(foo *ary)]);
}
nested references to C<$VAR>I<n> will be undefined, since a recursive
structure cannot be constructed using one Perl statement. You should set the
C<Purity> flag to 1 to get additional statements that will correctly fill in
-these references.
+these references. Moreover, if C<eval>ed when strictures are in effect,
+you need to ensure that any variables it accesses are previously declared.
In the extended usage form, the references to be dumped can be given
user-specified names. If a name begins with a C<*>, the output will
Returns the stringified form of the values stored in the object (preserving
the order in which they were supplied to C<new>), subject to the
-configuration options below. In an array context, it returns a list
+configuration options below. In a list context, it returns a list
of strings corresponding to the supplied values.
The second form, for convenience, simply calls the C<new> method on its
arguments before dumping the object immediately.
-=item I<$OBJ>->Dumpxs I<or> I<PACKAGE>->Dumpxs(I<ARRAYREF [>, I<ARRAYREF]>)
-
-This method is available if you were able to compile and install the XSUB
-extension to C<Data::Dumper>. It is exactly identical to the C<Dump> method
-above, only about 4 to 5 times faster, since it is written entirely in C.
-
=item I<$OBJ>->Seen(I<[HASHREF]>)
Queries or adds to the internal table of already encountered references.
are encountered subsequently. This is useful especially for properly
dumping subroutine references.
-Expects a anonymous hash of name => value pairs. Same rules apply for names
+Expects an anonymous hash of name => value pairs. Same rules apply for names
as in C<new>. If no argument is supplied, will return the "seen" list of
-name => value pairs, in an array context. Otherwise, returns the object
+name => value pairs, in a list context. Otherwise, returns the object
itself.
=item I<$OBJ>->Values(I<[ARRAYREF]>)
Returns the stringified form of the values in the list, subject to the
configuration options below. The values will be named C<$VAR>I<n> in the
output, where I<n> is a numeric suffix. Will return a list of strings
-in an array context.
-
-=item DumperX(I<LIST>)
-
-Identical to the C<Dumper()> function above, but this calls the XSUB
-implementation. Only available if you were able to compile and install
-the XSUB extensions in C<Data::Dumper>.
+in a list context.
=back
=over 4
-=item $Data::Dumper::Indent I<or> I<$OBJ>->Indent(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Indent I<or> I<$OBJ>->Indent(I<[NEWVAL]>)
Controls the style of indentation. It can be set to 0, 1, 2 or 3. Style 0
spews output without any newlines, indentation, or spaces between list
with their index (but the comment is on its own line, so array output
consumes twice the number of lines). Style 2 is the default.
-=item $Data::Dumper::Purity I<or> I<$OBJ>->Purity(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Purity I<or> I<$OBJ>->Purity(I<[NEWVAL]>)
Controls the degree to which the output can be C<eval>ed to recreate the
supplied reference structures. Setting it to 1 will output additional perl
statements that will correctly recreate nested references. The default is
0.
-=item $Data::Dumper::Pad I<or> I<$OBJ>->Pad(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Pad I<or> I<$OBJ>->Pad(I<[NEWVAL]>)
Specifies the string that will be prefixed to every line of the output.
Empty string by default.
-=item $Data::Dumper::Varname I<or> I<$OBJ>->Varname(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Varname I<or> I<$OBJ>->Varname(I<[NEWVAL]>)
Contains the prefix to use for tagging variable names in the output. The
default is "VAR".
-=item $Data::Dumper::Useqq I<or> I<$OBJ>->Useqq(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Useqq I<or> I<$OBJ>->Useqq(I<[NEWVAL]>)
When set, enables the use of double quotes for representing string values.
Whitespace other than space will be represented as C<[\n\t\r]>, "unsafe"
characters will be backslashed, and unprintable characters will be output as
quoted octal integers. Since setting this variable imposes a performance
-penalty, the default is 0. The C<Dumpxs()> method does not honor this
-flag yet.
+penalty, the default is 0. C<Dump()> will run slower if this flag is set,
+since the fast XSUB implementation doesn't support it yet.
-=item $Data::Dumper::Terse I<or> I<$OBJ>->Terse(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Terse I<or> I<$OBJ>->Terse(I<[NEWVAL]>)
When set, Data::Dumper will emit single, non-self-referential values as
atoms/terms rather than statements. This means that the C<$VAR>I<n> names
will be avoided where possible, but be advised that such output may not
always be parseable by C<eval>.
-=item $Data::Dumper::Freezer I<or> $I<OBJ>->Freezer(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Freezer I<or> $I<OBJ>->Freezer(I<[NEWVAL]>)
Can be set to a method name, or to an empty string to disable the feature.
Data::Dumper will invoke that method via the object before attempting to
only perl data types after the method has been called. Defaults to an empty
string.
-=item $Data::Dumper::Toaster I<or> $I<OBJ>->Toaster(I<[NEWVAL]>)
+If an object does not support the method specified (determined using
+UNIVERSAL::can()) then the call will be skipped. If the method dies a
+warning will be generated.
+
+=item *
+
+$Data::Dumper::Toaster I<or> $I<OBJ>->Toaster(I<[NEWVAL]>)
Can be set to a method name, or to an empty string to disable the feature.
Data::Dumper will emit a method call for any objects that are to be dumped
-using the syntax C<bless(DATA, CLASS)->METHOD()>. Note that this means that
+using the syntax C<bless(DATA, CLASS)-E<gt>METHOD()>. Note that this means that
the method specified will have to perform any modifications required on the
object (like creating new state within it, and/or reblessing it in a
different package) and then return it. The client is responsible for making
sure the method can be called via the object, and that it returns a valid
object. Defaults to an empty string.
-=item $Data::Dumper::Deepcopy I<or> $I<OBJ>->Deepcopy(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Deepcopy I<or> $I<OBJ>->Deepcopy(I<[NEWVAL]>)
Can be set to a boolean value to enable deep copies of structures.
Cross-referencing will then only be done when absolutely essential
(i.e., to break reference cycles). Default is 0.
-=item $Data::Dumper::Quotekeys I<or> $I<OBJ>->Quotekeys(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Quotekeys I<or> $I<OBJ>->Quotekeys(I<[NEWVAL]>)
Can be set to a boolean value to control whether hash keys are quoted.
A false value will avoid quoting hash keys when it looks like a simple
string. Default is 1, which will always enclose hash keys in quotes.
-=item $Data::Dumper::Bless I<or> $I<OBJ>->Bless(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Bless I<or> $I<OBJ>->Bless(I<[NEWVAL]>)
Can be set to a string that specifies an alternative to the C<bless>
builtin operator used to create objects. A function with the specified
name should exist, and should accept the same arguments as the builtin.
Default is C<bless>.
-=item $Data::Dumper::Maxdepth I<or> $I<OBJ>->Maxdepth(I<[NEWVAL]>)
+=item *
+
+$Data::Dumper::Pair I<or> $I<OBJ>->Pair(I<[NEWVAL]>)
+
+Can be set to a string that specifies the separator between hash keys
+and values. To dump nested hash, array and scalar values to JavaScript,
+use: C<$Data::Dumper::Pair = ' : ';>. Implementing C<bless> in JavaScript
+is left as an exercise for the reader.
+A function with the specified name exists, and accepts the same arguments
+as the builtin.
+
+Default is: C< =E<gt> >.
+
+=item *
+
+$Data::Dumper::Maxdepth I<or> $I<OBJ>->Maxdepth(I<[NEWVAL]>)
Can be set to a positive integer that specifies the depth beyond which
which we don't venture into a structure. Has no effect when
want to see more than enough). Default is 0, which means there is
no maximum depth.
+=item *
+
+$Data::Dumper::Useperl I<or> $I<OBJ>->Useperl(I<[NEWVAL]>)
+
+Can be set to a boolean value which controls whether the pure Perl
+implementation of C<Data::Dumper> is used. The C<Data::Dumper> module is
+a dual implementation, with almost all functionality written in both
+pure Perl and also in XS ('C'). Since the XS version is much faster, it
+will always be used if possible. This option lets you override the
+default behavior, usually for testing purposes only. Default is 0, which
+means the XS implementation will be used if possible.
+
+=item *
+
+$Data::Dumper::Sortkeys I<or> $I<OBJ>->Sortkeys(I<[NEWVAL]>)
+
+Can be set to a boolean value to control whether hash keys are dumped in
+sorted order. A true value will cause the keys of all hashes to be
+dumped in Perl's default sort order. Can also be set to a subroutine
+reference which will be called for each hash that is dumped. In this
+case C<Data::Dumper> will call the subroutine once for each hash,
+passing it the reference of the hash. The purpose of the subroutine is
+to return a reference to an array of the keys that will be dumped, in
+the order that they should be dumped. Using this feature, you can
+control both the order of the keys, and which keys are actually used. In
+other words, this subroutine acts as a filter by which you can exclude
+certain keys from being dumped. Default is 0, which means that hash keys
+are not sorted.
+
+=item *
+
+$Data::Dumper::Deparse I<or> $I<OBJ>->Deparse(I<[NEWVAL]>)
+
+Can be set to a boolean value to control whether code references are
+turned into perl source code. If set to a true value, C<B::Deparse>
+will be used to get the source of the code reference. Using this option
+will force using the Perl implementation of the dumper, since the fast
+XSUB implementation doesn't support it.
+
+Caution : use this option only if you know that your coderefs will be
+properly reconstructed by C<B::Deparse>.
+
=back
=head2 Exports
$boo = [ 1, [], "abcd", \*foo,
{1 => 'a', 023 => 'b', 0x45 => 'c'},
\\"p\q\'r", $foo, $fuz];
-
+
########
# simple usage
########
$Data::Dumper::Useqq = 1; # print strings in double quotes
print Dumper($boo);
-
-
+
+ $Data::Dumper::Pair = " : "; # specify hash key/value separator
+ print Dumper($boo);
+
+
########
# recursive structures
########
-
+
@c = ('c');
$c = \@c;
$b = {};
$b->{b} = $a->[1];
$b->{c} = $a->[2];
print Data::Dumper->Dump([$a,$b,$c], [qw(a b c)]);
-
-
+
+
$Data::Dumper::Purity = 1; # fill in the holes for eval
print Data::Dumper->Dump([$a, $b], [qw(*a b)]); # print as @a
print Data::Dumper->Dump([$b, $a], [qw(*b a)]); # print as %b
-
-
+
+
$Data::Dumper::Deepcopy = 1; # avoid cross-refs
print Data::Dumper->Dump([$b, $a], [qw(*b a)]);
-
-
+
+
$Data::Dumper::Purity = 0; # avoid cross-refs
print Data::Dumper->Dump([$b, $a], [qw(*b a)]);
-
+
########
# deep structures
########
-
+
$a = "pearl";
$b = [ $a ];
$c = { 'b' => $b };
$Data::Dumper::Maxdepth = 3; # no deeper than 3 refs down
print Data::Dumper->Dump([$f], [qw(f)]);
-
+
########
# object-oriented usage
########
-
+
$d = Data::Dumper->new([$a,$b], [qw(a b)]);
$d->Seen({'*c' => $c}); # stash a ref without printing it
$d->Indent(3);
print $d->Dump;
$d->Reset->Purity(0); # empty the seen cache
print join "----\n", $d->Dump;
-
-
+
+
########
# persistence
########
-
+
package Foo;
sub new { bless { state => 'awake' }, shift }
sub Freeze {
$s->{state} = 'asleep';
return bless $s, 'Foo::ZZZ';
}
-
+
package Foo::ZZZ;
sub Thaw {
my $s = shift;
$s->{state} = 'awake';
return bless $s, 'Foo';
}
-
+
package Foo;
use Data::Dumper;
$a = Foo->new;
print $c;
$d = eval $c;
print Data::Dumper->Dump([$d], ['d']);
-
-
+
+
########
# symbol substitution (useful for recreating CODE refs)
########
-
+
sub foo { print "foo speaking\n" }
*other = \&foo;
$bar = [ \&other ];
print $d->Dump;
+ ########
+ # sorting and filtering hash keys
+ ########
+
+ $Data::Dumper::Sortkeys = \&my_filter;
+ my $foo = { map { (ord, "$_$_$_") } 'I'..'Q' };
+ my $bar = { %$foo };
+ my $baz = { reverse %$foo };
+ print Dumper [ $foo, $bar, $baz ];
+
+ sub my_filter {
+ my ($hash) = @_;
+ # return an array ref containing the hash keys to dump
+ # in the order that you want them to be dumped
+ return [
+ # Sort the keys of %$foo in reverse numeric order
+ $hash eq $foo ? (sort {$b <=> $a} keys %$hash) :
+ # Only dump the odd number keys of %$bar
+ $hash eq $bar ? (grep {$_ % 2} keys %$hash) :
+ # Sort keys in default order for all other hashes
+ (sort keys %$hash)
+ ];
+ }
+
=head1 BUGS
Due to limitations of Perl subroutine call semantics, you cannot pass an
array or hash. Prepend it with a C<\> to pass its reference instead. This
-will be remedied in time, with the arrival of prototypes in later versions
-of Perl. For now, you need to use the extended usage form, and prepend the
+will be remedied in time, now that Perl has subroutine prototypes.
+For now, you need to use the extended usage form, and prepend the
name with a C<*> to output it as a hash or array.
C<Data::Dumper> cheats with CODE references. If a code reference is
-encountered in the structure being processed, an anonymous subroutine that
+encountered in the structure being processed (and if you haven't set
+the C<Deparse> flag), an anonymous subroutine that
contains the string '"DUMMY"' will be inserted in its place, and a warning
will be printed if C<Purity> is set. You can C<eval> the result, but bear
in mind that the anonymous sub that gets created is just a placeholder.
representation of a compiled piece of code, I hope. If you have prior
knowledge of all the code refs that your data structures are likely
to have, you can use the C<Seen> method to pre-seed the internal reference
-table and make the dumped output point to them, instead. See L<EXAMPLES>
+table and make the dumped output point to them, instead. See L</EXAMPLES>
above.
-The C<Useqq> flag is not honored by C<Dumpxs()> (it always outputs
-strings in single quotes).
+The C<Useqq> and C<Deparse> flags makes Dump() run slower, since the
+XSUB implementation does not support them.
SCALAR objects have the weirdest looking C<bless> workaround.
+Pure Perl version of C<Data::Dumper> escapes UTF-8 strings correctly
+only in Perl 5.8.0 and later.
+
+=head2 NOTE
+
+Starting from Perl 5.8.1 different runs of Perl will have different
+ordering of hash keys. The change was done for greater security,
+see L<perlsec/"Algorithmic Complexity Attacks">. This means that
+different runs of Perl will have different Data::Dumper outputs if
+the data contains hashes. If you need to have identical Data::Dumper
+outputs from different runs of Perl, use the environment variable
+PERL_HASH_SEED, see L<perlrun/PERL_HASH_SEED>. Using this restores
+the old (platform-specific) ordering: an even prettier solution might
+be to use the C<Sortkeys> filter of Data::Dumper.
=head1 AUTHOR
This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
-
=head1 VERSION
-Version 2.11 (unreleased)
+Version 2.121 (Aug 24 2003)
=head1 SEE ALSO