Dumpxs#

Serialize one or more values into valid Perl code, fast.

Dumpxs and Dump take the same arguments and produce the same output; Dumpxs is the faster of the two, and Dump delegates here unless $Data::Dumper::Useperl is true.

Synopsis#

use Data::Dumper;
print Data::Dumper->new([\%h, \@a], ['hash', 'array'])->Dumpxs;
print Data::Dumper::Dumpxs('Data::Dumper', [\%h], ['hash']);

What you get back#

In scalar context, a single string containing one $VAR = ...; statement per input value, separated by $self->{sep} (default "\n"). In list context, one string per input - useful when you want to post-process each dump separately.

With Terse(1), the $VAR = prefix and trailing ; are dropped and you get a bare Perl expression suitable for embedding.

Examples#

Named output, default formatting:

my %h = (a => 1, b => [2, 3]);
print Data::Dumper->new([\%h], ['h'])->Dumpxs;
# $h = {
#   'a' => 1,
#   'b' => [2, 3]
# };

Compact, sorted, double-quoted:

print Data::Dumper->new([\%h])
                  ->Indent(0)->Sortkeys(1)->Useqq(1)->Dumpxs;
# $VAR1 = {"a" => 1,"b" => [2,3]};

Circular structure - the cycle is emitted as a backref, not an infinite expansion:

my @a = (1, 2);
push @a, \@a;
print Data::Dumper->new([\@a])->Dumpxs;
# $VAR1 = [1, 2, $VAR1];

List context gives you one string per argument:

my ($s1, $s2) = Data::Dumper->new([\%h, \@a])->Dumpxs;

Edge cases#

  • First argument is not a blessed hashref: Dumpxs will call new() internally using the remaining arguments, so Data::Dumper::Dumpxs('Data::Dumper', \@vals, \@names) works.

  • maxrecurse exceeded: croaks with "Recursion limit of N exceeded" after finishing the current top-level value so partial output is not lost from the caller’s perspective.

  • maxdepth exceeded: prints the quoted stringification of the ref (e.g. 'ARRAY(0x...)') at the cut-off point rather than croaking.

  • CODE references: emitted as sub { "DUMMY" } unless Deparse(1) is set, in which case the deparsed source is emitted.

  • Regexp references: emitted as qr/.../flags.

  • Sortkeys as a coderef: called once per hash to obtain the key order; a truthy non-coderef sorts alphabetically.

See also#

  • Dump - the pure-Perl fallback; identical output, slower.

  • Dumper - the procedural one-liner wrapping new(...)->Dumpxs.

  • Seen - pre-seed the seen-table to name pre-existing references.

  • Reset - clear the seen-table between unrelated Dumpxs calls.