NAME

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

SYNOPSIS

 package Some::Role;

 use Role::Tiny;

 sub foo { ... }

 sub bar { ... }

 around baz => sub { ... }

 1;

else where

 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.

• 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 first wins. In a more complete system (see Moose) roles are checked to see if they clash. The goal of this is to be much simpler, hence disallowing composition of multiple roles at once.

METHODS

apply_role_to_package

 Role::Tiny->apply_role_to_package('Some::Package', 'Some::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.

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.

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

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::Role2';

Composes another role into the current role. Only one role may be composed in at a time to allow the code to remain as simple as possible.

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.

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.

If you don't want method modifiers and do want to be forcibly restricted to a single role application per class, Ovid's Role::Basic exists. But Stevan Little (the Moose author) and I are both still convinced that he's Doing It Wrong.

AUTHOR

mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>

CONTRIBUTORS

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

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

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

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

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

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

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

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

perigrin - Chris Prather (cpan:PERIGRIN) <chris@prather.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.

cpanm Role::Tiny

perl -MCPAN -e shell
install Role::Tiny