Provided by: libdata-dmp-perl_0.14-1_all 
NAME
Data::Dmp - Dump Perl data structures as Perl code
VERSION
This document describes version 0.14 of Data::Dmp (from Perl distribution Data-Dmp), released on
2015-12-27.
SYNOPSIS
use Data::Dmp; # exports dd() and dmp()
dd [1, 2, 3]; # prints "[1,2,3]"
$a = dmp({a => 1}); # -> "{a=>1}"
DESCRIPTION
Data::Dmp is a Perl dumper like Data::Dumper. It's compact (only about 150 lines of code long), starts
fast and does not use other module except Regexp::Stringify when dumping regexes. It produces compact
output (similar to Data::Dumper::Concise). It roughly has the same speed as Data::Dumper (usually a bit
faster for smaller structures), but does not offer the various formatting options. It supports dumping
objects, regexes, circular structures, coderefs. Its code is based on Data::Dump.
FUNCTIONS
dd($data, ...) => $data ...
Exported by default. Like "Data::Dump"'s "dd" (a.k.a. "dump"), print one or more data to STDOUT. Unlike
"Data::Dump"'s "dd", it always prints and return the original data (like XXX), making it convenient to
insert into expressions. This also removes ambiguity and saves one "wantarray()" call.
dmp($data, ...) => $str
Exported by default. Return dump result as string. Unlike "Data::Dump"'s "dd" (a.k.a. "dump"), it never
prints and only return the data.
SETTINGS
$Data::Dmp::OPT_PERL_VERSION => str (default: 5.010)
Set target Perl version. If you set this to, say 5.010, then the dumped code will keep compatibility with
Perl 5.10.0. This is used in the following ways:
• passed to Regexp::Stringify
• when dumping code references
For example, in perls earlier than 5.016, feature.pm does not understand:
no feature ':all';
so we replace it with:
no feature;
$Data::Dmp::OPT_REMOVE_PRAGMAS => bool (default: 0)
If set to 1, then pragmas at the start of coderef dump will be removed. Coderef dump is produced by
B::Deparse and is of the form like:
sub { use feature 'current_sub', 'evalbytes', 'fc', 'say', 'state', 'switch', 'unicode_strings', 'unicode_eval'; $a <=> $b }
If you want to dump short coderefs, the pragmas might be distracting. You can turn turn on this option
which will make the above dump become:
sub { $a <=> $b }
Note that without the pragmas, the dump might be incorrect.
BENCHMARKS
[1..10]:
Rate Data::Dump Data::Dumper Data::Dmp
Data::Dump 28356+-42/s -- -66.8% -77.5%
Data::Dumper 85500+-290/s 201.5+-1.1% -- -32.3%
Data::Dmp 126260+-210/s 345.26+-1% 47.67+-0.56% --
[1..100]:
Rate Data::Dump Data::Dumper Data::Dmp
Data::Dump 3449.1+-5.1/s -- -77.4% -78.3%
Data::Dumper 15252+-31/s 342.2+-1.1% -- -4.1%
Data::Dmp 15905.9+-5.8/s 361.16+-0.7% 4.29+-0.22% --
Some mixed structure:
Rate Data::Dump Data::Dmp Data::Dumper
Data::Dump 7840+-13/s -- -74.1% -79.2%
Data::Dmp 30302+-42/s 286.49+-0.83% -- -19.5%
Data::Dumper 37637+-72/s 380+-1.2% 24.21+-0.29% --
FAQ
When to use Data::Dmp? How does it compare to other dumper modules?
Data::Dmp might be suitable for you if you want a relatively fast pure-Perl data structure dumper to
eval-able Perl code. It produces compact, single-line Perl code but offers little/no formatting options.
Data::Dmp and Data::Dump module family usually produce Perl code that is "more eval-able", e.g. it can
recreate circular structure.
Data::Dump produces nicer output (some alignment, use of range operator to shorten lists, use of base64
for binary data, etc) but no built-in option to produce compact/single-line output. It's also relatively
slow. I usually use its variant, Data::Dump::Color, for console debugging.
Data::Dumper is core module, offers a lot of formatting options (like disabling hash key sorting, setting
verboseness/indent level, and so on) but you usually have to configure it quite a bit before it does
exactly like you want (that's why there are modules on CPAN that are just wrapping Data::Dumper with some
configuration, like Data::Dumper::Concise et al). It does not support dumping Perl code that can recreate
circular structures.
Of course, dumping to eval-able Perl code is slow (not to mention the cost of re-loading the code back to
in-memory data, via eval-ing) compared to dumping to JSON, YAML, Sereal, or other format. So you need to
decide first whether this is the appropriate route you want to take. (But note that there is also
Data::Dumper::Limited and Data::Undump which uses a format similar to Data::Dumper but lets you load the
serialized data without eval-ing them, thus achieving the speed comparable to JSON::XS).
SEE ALSO
Data::Dump and other variations/derivate works in Data::Dump::*.
Data::Dumper and its variants.
Data::Printer.
YAML, JSON, Storable, Sereal, and other serialization formats.
HOMEPAGE
Please visit the project's homepage at <https://metacpan.org/release/Data-Dmp>.
SOURCE
Source repository is at <https://github.com/perlancar/perl-Data-Dmp>.
BUGS
Please report any bugs or feature requests on the bugtracker website
<https://rt.cpan.org/Public/Dist/Display.html?Name=Data-Dmp>
When submitting a bug or request, please include a test-file or a patch to an existing test-file that
illustrates the bug or desired feature.
AUTHOR
perlancar <perlancar@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2015 by perlancar@cpan.org.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5
programming language system itself.
perl v5.22.1 2016-01-04 Data::Dmp(3pm)