phpman > perldoc > Role::Tiny(3pm)

NAME
    Role::Tiny - Roles: a nouvelle cuisine portion size slice of Moose

SYNOPSIS
     package Some::Role;

     use Role::Tiny;

     sub foo { ... }

     sub bar { ... }

     around baz => sub { ... };

     1;

    elsewhere

     package Some::Class;

     use Role::Tiny::With;

     # bar gets imported, but not foo
     with 'Some::Role';

     sub foo { ... }

     # baz is wrapped in the around modifier by Class::Method::Modifiers
     sub baz { ... }

     1;

    If you wanted attributes as well, look at Moo::Role.

DESCRIPTION
    "Role::Tiny" is a minimalist role composition tool.

ROLE COMPOSITION
    Role composition can be thought of as much more clever and meaningful multiple inheritance. The
    basics of this implementation of roles is:

    * If a method is already defined on a class, that method will not be composed in from the role.
      A method inherited by a class gets overridden by the role's method of the same name, though.

    * If a method that the role "requires" to be implemented is not implemented, role application
      will fail loudly.

    Unlike Class::C3, where the last class inherited from "wins," role composition is the other way
    around, where the class wins. If multiple roles are applied in a single call (single with
    statement), then if any of their provided methods clash, an exception is raised unless the class
    provides a method since this conflict indicates a potential problem.

  ROLE METHODS
    All subs created after importing Role::Tiny will be considered methods to be composed. For
    example:

        package MyRole;
        use List::Util qw(min);
        sub mysub { }
        use Role::Tiny;
        use List::Util qw(max);
        sub mymethod { }

    In this role, "max" and "mymethod" will be included when composing MyRole, and "min" and "mysub"
    will not. For additional control, namespace::clean can be used to exclude undesired subs from
    roles.

IMPORTED SUBROUTINES
  requires
     requires qw(foo bar);

    Declares a list of methods that must be defined to compose role.

  with
     with 'Some::Role1';

     with 'Some::Role1', 'Some::Role2';

    Composes another role into the current role (or class via Role::Tiny::With).

    If you have conflicts and want to resolve them in favour of Some::Role1 you can instead write:

     with 'Some::Role1';
     with 'Some::Role2';

    If you have conflicts and want to resolve different conflicts in favour of different roles,
    please refactor your codebase.

  before
     before foo => sub { ... };

    See "before method(s) => sub { ... };" in Class::Method::Modifiers for full documentation.

    Note that since you are not required to use method modifiers, Class::Method::Modifiers is lazily
    loaded and we do not declare it as a dependency. If your Role::Tiny role uses modifiers you must
    depend on both Class::Method::Modifiers and Role::Tiny.

  around
     around foo => sub { ... };

    See "around method(s) => sub { ... };" in Class::Method::Modifiers for full documentation.

    Note that since you are not required to use method modifiers, Class::Method::Modifiers is lazily
    loaded and we do not declare it as a dependency. If your Role::Tiny role uses modifiers you must
    depend on both Class::Method::Modifiers and Role::Tiny.

  after
     after foo => sub { ... };

    See "after method(s) => sub { ... };" in Class::Method::Modifiers for full documentation.

    Note that since you are not required to use method modifiers, Class::Method::Modifiers is lazily
    loaded and we do not declare it as a dependency. If your Role::Tiny role uses modifiers you must
    depend on both Class::Method::Modifiers and Role::Tiny.

  Strict and Warnings
    In addition to importing subroutines, using "Role::Tiny" applies strict and warnings to the
    caller.

SUBROUTINES
  does_role
     if (Role::Tiny::does_role($foo, 'Some::Role')) {
       ...
     }

    Returns true if class has been composed with role.

    This subroutine is also installed as ->does on any class a Role::Tiny is composed into unless
    that class already has an ->does method, so

      if ($foo->does('Some::Role')) {
        ...
      }

    will work for classes but to test a role, one must use ::does_role directly.

    Additionally, Role::Tiny will override the standard Perl "DOES" method for your class. However,
    if "any" class in your class' inheritance hierarchy provides "DOES", then Role::Tiny will not
    override it.

METHODS
  make_role
     Role::Tiny->make_role('Some::Role');

    Makes a package into a role, but does not export any subs into it.

  apply_roles_to_package
     Role::Tiny->apply_roles_to_package(
       'Some::Package', 'Some::Role', 'Some::Other::Role'
     );

    Composes role with package. See also Role::Tiny::With.

  apply_roles_to_object
     Role::Tiny->apply_roles_to_object($foo, qw(Some::Role1 Some::Role2));

    Composes roles in order into object directly. Object is reblessed into the resulting class. Note
    that the object's methods get overridden by the role's ones with the same names.

  create_class_with_roles
     Role::Tiny->create_class_with_roles('Some::Base', qw(Some::Role1 Some::Role2));

    Creates a new class based on base, with the roles composed into it in order. New class is
    returned.

  is_role
     Role::Tiny->is_role('Some::Role1')

    Returns true if the given package is a role.

CAVEATS
    *   On perl 5.8.8 and earlier, applying a role to an object won't apply any overloads from the
        role to other copies of the object.

    *   On perl 5.16 and earlier, applying a role to a class won't apply any overloads from the role
        to any existing instances of the class.

SEE ALSO
    Role::Tiny is the attribute-less subset of Moo::Role; Moo::Role is a meta-protocol-less subset
    of the king of role systems, Moose::Role.

    Ovid's Role::Basic provides roles with a similar scope, but without method modifiers, and having
    some extra usage restrictions.

AUTHOR
    mst - Matt S. Trout (cpan:MSTROUT) <mst AT shadowcat.uk>

CONTRIBUTORS
    dg - David Leadbeater (cpan:DGL) <dgl AT dgl.cx>

    frew - Arthur Axel "fREW" Schmidt (cpan:FREW) <frioux AT gmail.com>

    hobbs - Andrew Rodland (cpan:ARODLAND) <arodland AT cpan.org>

    jnap - John Napiorkowski (cpan:JJNAPIORK) <jjn1056 AT yahoo.com>

    ribasushi - Peter Rabbitson (cpan:RIBASUSHI) <ribasushi AT cpan.org>

    chip - Chip Salzenberg (cpan:CHIPS) <chip AT pobox.com>

    ajgb - Alex J. G. Burzyński (cpan:AJGB) <ajgb AT cpan.org>

    doy - Jesse Luehrs (cpan:DOY) <doy at tozt dot net>

    perigrin - Chris Prather (cpan:PERIGRIN) <chris AT prather.org>

    Mithaldu - Christian Walde (cpan:MITHALDU) <walde.christian AT googlemail.com>

    ilmari - Dagfinn Ilmari Mannsåker (cpan:ILMARI) <ilmari AT ilmari.org>

    tobyink - Toby Inkster (cpan:TOBYINK) <tobyink AT cpan.org>

    haarg - Graham Knop (cpan:HAARG) <haarg AT haarg.org>

COPYRIGHT
    Copyright (c) 2010-2012 the Role::Tiny "AUTHOR" and "CONTRIBUTORS" as listed above.

LICENSE
    This library is free software and may be distributed under the same terms as perl itself.