MooX::Options - Explicit Options eXtension for Object Class


In :

  package myOptions;
  use Moo;
  use MooX::Options;

  option 'show_this_file' => (
      is => 'ro',
      format => 's',
      required => 1,
      doc => 'the file to display'

In :

  use myOptions;
  use Path::Class;

  my $opt = myOptions->new_with_options;

  print "Content of the file : ",

To use it :

  perl --show_this_file=myFile.txt
  Content of the file: myFile content

The help message :

  perl --help
  USAGE: [-h] [long options...]

      --show_this_file: String
          the file to display

      -h --help:
          show this help message

          show the manual

The usage message :

  perl --usage
  USAGE: [ --show_this_file=String ] [ --usage ] [ --help ] [ --man ]

The manual :

  perl --man


Create a command line tool with your Moo, Moose objects.

Everything is explicit. You have an option keyword to replace the usual has to explicitly use your attribute into the command line.

The option keyword takes additional parameters and uses Getopt::Long::Descriptive to generate a command line tool.


Enhancing existing attributes

One can now convert an existing attribute into an option for obvious reasons.

  package CommonRole;

  use Moo::Role;

  has attr => (is => "ro", ...);

  sub common_logic { ... }


  package Suitable::Cmd::CLI;

  use Moo;
  use MooX::Cmd;
  use MooX::Options;

  with "CommonRole";

  option '+attr' => (format => 's', repeatable => 1);

  sub execute { shift->common_logic }


  package Suitable::Web::Request::Handler;

  use Moo;

  with "CommonRole";

  sub all_suits { shift->common_logic }


  package Suitable::Web;

  use Dancer2;
  use Suitable::Web::Request::Handler;

  set serializer => "JSON";

  get '/suits' => sub {
      $my $reqh = Suitable::Web::Request::Handler->new( attr => config->{suit_attr} );



Of course there more ways to to it, Jedi or Catalyst shall be fine, either.

Rename negativable into negatable

Since users stated that negativable is not a reasonable word, the flag is renamed into negatable. Those who will 2020 continue use negativable might or might not be warned about soon depreciation.

Replace Locale::TextDomain by MooX::Locale::Passthrough

Locale::TextDomain is broken (technically and functionally) and causes a lot of people to avoid MooX::Options or hack around. Both is unintened.

So introduce MooX::Locale::Passthrough to allow any vendor to add reasonable localization, eg. by composing MooX::Locale::TextDomain::OO into it's solution and initialize the localization in a reasonable way.

Make lazy loaded features optional

Since some features aren't used on a regular basis, their dependencies have been downgraded to recommended or suggested. The optional features are:


This feature allowes one to split option arguments at a defined character and always return an array (implicit flag repeatable).

  option "search_path" => ( is => "ro", required => 1, autosplit => ":", format => "s" );

However, this feature requires following modules are provided:

json format

This feature allowes one to invoke a script like

  $ my-tool --json-attr '{ "gem": "sapphire", "color": "blue" }'

It might be a reasonable enhancement to handles.

Handling JSON formatted arguments requires any of those modules are loded:

Decouple autorange and autosplit

Until 4.023, any option which had autorange enabled got autosplit enabled, too. Since autosplit might not work correctly and for a reasonable amount of users the fact of

  $ my-tool --range 1..5

is all they desire, autosplit will enabled only when the dependencies of autosplit are fulfilled.


The list of the methods automatically imported into your class.


It will parse your command line params and your inline params, validate and call the new method.

  myTool --str=ko

  t->new_with_options()->str # ko
  t->new_with_options(str => 'ok')->str #ok


The option keyword replaces the has method and adds support for special options for the command line only.

See "OPTION PARAMETERS" for the documentation.

options_usage | --help

It displays the usage message and returns the exit code.

  my $t = t->new_with_options();
  my $exit_code = 1;
  my $pre_message = "str is not valid";
  $t->options_usage($exit_code, $pre_message);

This method is also automatically fired if the command option "--help" is passed.

  myTool --help

options_man | --man

It displays the manual.

  my $t = t->new_with_options();

This is automatically fired if the command option "--man" is passed.

  myTool --man

options_short_usage | --usage

It displays a short version of the help message.

  my $t = t->new_with_options();

This is automatically fired if the command option "--usage" is passed.

  myTool --usage


The list of parameters supported by MooX::Options.


Passes extra arguments for Getopt::Long::Descriptive. It is useful if you want to configure Getopt::Long.

  use MooX::Options flavour => [qw( pass_through )];

Any flavour is passed to Getopt::Long as a configuration, check the doc to see what is possible.


By default, @ARGV is protected. If you want to do something else on it, use this option and it will change the real @ARGV.

  use MooX::Options protect_argv => 0;


If you have Role with options and you want to deactivate some of them, you can use this parameter. In that case, the option keyword will just work like an has.

  use MooX::Options skip_options => [qw/multi/];


By default, arguments passed to new_with_options have a higher priority than the command line options.

This parameter will give the command line an higher priority.

  use MooX::Options prefer_commandline => 1;


This parameter will load MooX::Options in your module. The config option will be used between the command line and parameters.

myTool :

  use MooX::Options with_config_from_file => 1;

In /etc/myTool.json

  {"test" : 1}


This Parameter will load MooX::Locale::TextDomain::OO into your module as well as into MooX::Options::Descriptive::Usage.

No further action is taken, no language is chosen - everything keep in control.

Please read Locale::TextDomain::OO carefully how to enable the desired translation setup accordingly.


This parameter is passed to Getopt::Long::Descriptive::describe_options() as the first parameter.

It is a "sprintf"-like string that is used in generating the first line of the usage message. It's a one-line summary of how the command is to be invoked. The default value is "USAGE: %c %o".

%c will be replaced with what Getopt::Long::Descriptive thinks is the program name (it's computed from $0, see "prog_name").

%o will be replaced with a list of the short options, as well as the text "[long options...]" if any have been defined.

The rest of the usage description can be used to summarize what arguments are expected to follow the program's options, and is entirely free-form.

Literal "%" characters will need to be written as "%%", just like with "sprintf".


This indicate the char to use for spacer. Please only use 1 char otherwize the text will be too long.

The default char is " ".

  use MooX::Options space => '+'

Then the "spacer_before" and "spacer_after" will use it for "man" and "help" message.

  option 'x' => (is => 'ro', spacer_before => 1, spacer_after => 1);


The keyword option extend the keyword has with specific parameters for the command line.

doc | documentation

Documentation for the command line option.


Documentation for the man page. By default the doc parameter will be used.

See also Man parameters to get more examples how to build a nice man page.


This attribute indicates that the parameter is mandatory. This attribute is not really used by MooX::Options but ensures that consistent error message will be displayed.


Format of the params, same as Getopt::Long::Descriptive.

  • i : integer

  • i@: array of integer

  • s : string

  • s@: array of string

  • f : float value

By default, it's a boolean value.

Take a look of available formats with Getopt::Long::Descriptive.

You need to understand that everything is explicit here. If you use Moose and your attribute has isa => 'Array[Int]', that will not imply the format i@.

format json : special format support

The parameter will be treated like a json string.

  option 'hash' => (is => 'ro', json => 1);

You can also use the json format

  option 'hash' => (is => 'ro', format => "json");

  myTool --hash='{"a":1,"b":2}' # hash = { a => 1, b => 2 }


It adds the negative version for the option.

  option 'verbose' => (is => 'ro', negatable => 1);

  myTool --verbose    # verbose = 1
  myTool --no-verbose # verbose = 0

The former name of this flag, negativable, is discouraged - since it's not a word.


It appends to the "format" the array attribute @.

I advise to add a default value to your attribute to always have an array. Otherwise the default value will be an undefined value.

  option foo => (is => 'rw', format => 's@', default => sub { [] });

  myTool --foo="abc" --foo="def" # foo = ["abc", "def"]


For repeatable option, you can add the autosplit feature with your specific parameters.

  option test => (is => 'ro', format => 'i@', default => sub {[]}, autosplit => ',');
  myTool --test=1 --test=2 # test = (1, 2)
  myTool --test=1,2,3      # test = (1, 2, 3)

It will also handle quoted params with the autosplit.

  option testStr => (is => 'ro', format => 's@', default => sub {[]}, autosplit => ',');

  myTool --testStr='a,b,"c,d",e,f' # testStr ("a", "b", "c,d", "e", "f")


For another repeatable option you can add the autorange feature with your specific parameters. This allows you to pass number ranges instead of passing each individual number.

  option test => (is => 'ro', format => 'i@', default => sub {[]}, autorange => 1);
  myTool --test=1 --test=2 # test = (1, 2)
  myTool --test=1,2,3      # test = (1, 2, 3)
  myTool --test=1,2,3..6   # test = (1, 2, 3, 4, 5, 6)

It will also handle quoted params like autosplit, and will not rangify them.

  option testStr => (is => 'ro', format => 's@', default => sub {[]}, autorange => 1);

  myTool --testStr='1,2,"3,a,4",5' # testStr (1, 2, "3,a,4", 5)

autosplit will be set to ',' if undefined. You may set autosplit to a different delimiter than ',' for your group separation, but the range operator '..' cannot be changed.

  option testStr => (is => 'ro', format => 's@', default => sub {[]}, autorange => 1, autosplit => '-');

  myTool --testStr='1-2-3-5..7' # testStr (1, 2, 3, 5, 6, 7) 


Long option can also have short version or aliased.

  option 'verbose' => (is => 'ro', short => 'v');

  myTool --verbose # verbose = 1
  myTool -v        # verbose = 1

  option 'account_id' => (is => 'ro', format => 'i', short => 'a|id');

  myTool --account_id=1
  myTool -a=1
  myTool --id=1

You can also use a shorter option without attribute :

  option 'account_id' => (is => 'ro', format => 'i');

  myTool --acc=1
  myTool --account=1


Specifies the order of the attribute. If you want to push some attributes at the end of the list. By default all options have an order set to 0, and options are sorted by their names.

  option 'at_the_end' => (is => 'ro', order => 999);


Hide option from doc but still an option you can use on command line.

  option 'debug' => (is => 'ro', doc => 'hidden');


  option 'debug' => (is => 'ro', hidden => 1);

spacer_before, spacer_after

Add spacer before or after or both the params

  option 'myoption' => (is => 'ro', spacer_before => 1, spacer_after => 1);


MooX::Options and Mo

MooX::Options is implemented as a frontend loader class and the real magic provided by a role composed into the caller by MooX::Options::import.

Since some required features (with, around) isn't provided by Mo, Class::Method::Modifiers must be loaded by any Mo class using MooX::Options, Role::Tiny::With is needed to inject the MooX::Options::Role and finally in the target package the private accessors to options_config and options_data are missing.

Concluding a reasonable support for Mo based classes is beyond the goal of this module. It's neither forbidden nor actively prevented, but won't be covered by any test nor actively supported.

If someome wants contribute guides how to use MooX::Options together with Mo or provide patches to solve this limitation - any support will granted.




Translation is now supported.

Use the dzil command to update the pot and merge into the po files.

  • dzil msg-init

    Create a new language po

  • dzil msg-scan

    Scan and generate or update the pot file

  • dzil msg-merge

    Update all languages using the pot file


  • sschober

    For implementation and German translation.


  • Matt S. Trout (mst) <>

    For his patience and advice.

  • Tomas Doran (t0m) <>

    To help me release the new version, and using it :)

  • Torsten Raudssus (Getty)

    to use it a lot in DuckDuckGo (go to see MooX module also)

  • Jens Rehsack (REHSACK)

    Use with PkgSrc, and many really good idea (MooX::Cmd, MooX::Options, and more to come I'm sure)

  • All contributors

    For improving and add more feature to MooX::Options


You can find documentation for this module with the perldoc command.

    perldoc MooX::Options

You can also look for information at:


celogeek <>


This software is copyright (c) 2013 by celogeek <>.

This software is copyright (c) 2017 by Jens Rehsack.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.