$Data::Dmp::OPT_PERL_VERSION => str (default: 5.010)¶

• 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)¶

 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.

$Data::Dmp::OPT_DEPARSE => bool (default: 1)¶

$Data::Dmp::OPT_STRINGIFY_NUMBERS => bool (default: 0)¶

dd($data, ...) => $data ...¶

dmp($data, ...) => $str¶

When to use Data::Dmp? How does it compare to other dumper modules?¶

Data::Dump produces visually 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 more suitable for debugging. It's also relatively slow. I usually use its variant, Data::Dump::Color, for console debugging.

Data::Dumper is a 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).

Is the output guaranteed to be single line dump?¶