# phpman > info > Moo::Role

Moo::[Role(3pm)](https://www.chedong.com/phpMan.php/man/Role/3pm/markdown)        User Contributed Perl Documentation       Moo::[Role(3pm)](https://www.chedong.com/phpMan.php/man/Role/3pm/markdown)

NAME
       [Moo::Role](https://www.chedong.com/phpMan.php/perldoc/Moo%3A%3ARole/markdown) - Minimal Object Orientation support for Roles

SYNOPSIS
         package [My::Role](https://www.chedong.com/phpMan.php/perldoc/My%3A%3ARole/markdown);

         use [Moo::Role](https://www.chedong.com/phpMan.php/perldoc/Moo%3A%3ARole/markdown);
         use strictures 2;

         sub foo { ... }

         sub bar { ... }

         has baz => (
           is => 'ro',
         );

         1;

       And elsewhere:

         package [Some::Class](https://www.chedong.com/phpMan.php/perldoc/Some%3A%3AClass/markdown);

         use Moo;
         use strictures 2;

         # bar gets imported, but not foo
         with '[My::Role](https://www.chedong.com/phpMan.php/perldoc/My%3A%3ARole/markdown)';

         sub foo { ... }

         1;

DESCRIPTION
       "[Moo::Role](https://www.chedong.com/phpMan.php/perldoc/Moo%3A%3ARole/markdown)" builds upon [Role::Tiny](https://www.chedong.com/phpMan.php/perldoc/Role%3A%3ATiny/markdown), so look there for most of the
       documentation on how this works (in particular, using "[Moo::Role](https://www.chedong.com/phpMan.php/perldoc/Moo%3A%3ARole/markdown)" also
       enables strict and warnings).  The main addition here is extra bits to
       make the roles more "Moosey;" which is to say, it adds "has".

IMPORTED SUBROUTINES
       See "IMPORTED SUBROUTINES" in [Role::Tiny](https://www.chedong.com/phpMan.php/perldoc/Role%3A%3ATiny/markdown) for all the other subroutines
       that are imported by this module.

   has
         has attr => (
           is => 'ro',
         );

       Declares an attribute for the class to be composed into.  See "has" in
       Moo for all options.

CLEANING UP IMPORTS
       [Moo::Role](https://www.chedong.com/phpMan.php/perldoc/Moo%3A%3ARole/markdown) cleans up its own imported methods and any imports declared
       before the "use [Moo::Role](https://www.chedong.com/phpMan.php/perldoc/Moo%3A%3ARole/markdown)" statement automatically.  Anything imported
       after "use [Moo::Role](https://www.chedong.com/phpMan.php/perldoc/Moo%3A%3ARole/markdown)" will be composed into consuming packages.  A
       package that consumes this role:

         package [My::Role::ID](https://www.chedong.com/phpMan.php/perldoc/My%3A%3ARole%3A%3AID/markdown);

         use [Digest::MD5](https://www.chedong.com/phpMan.php/perldoc/Digest%3A%3AMD5/markdown) qw(md5_hex);
         use [Moo::Role](https://www.chedong.com/phpMan.php/perldoc/Moo%3A%3ARole/markdown);
         use [Digest::SHA](https://www.chedong.com/phpMan.php/perldoc/Digest%3A%3ASHA/markdown) qw(sha1_hex);

         requires 'name';

         sub as_md5  { my ($self) = @_; return md5_hex($self->name);  }
         sub as_sha1 { my ($self) = @_; return sha1_hex($self->name); }

         1;

       ..will now have a "$self->sha1_hex()" method available to it that
       probably does not do what you expect.  On the other hand, a call to
       "$self->md5_hex()" will die with the helpful error message: "Can't
       locate object method "md5_hex"".

       See "CLEANING UP IMPORTS" in Moo for more details.

SUPPORT
       See Moo for support and contact information.

AUTHORS
       See Moo for authors.

COPYRIGHT AND LICENSE
       See Moo for the copyright and license.

perl v5.32.1                      2021-12-05                    Moo::[Role(3pm)](https://www.chedong.com/phpMan.php/man/Role/3pm/markdown)