Role::Tiny(3pm)

1Role::Tiny(3)         User Contributed Perl Documentation        Role::Tiny(3)
2
3
4

NAME

6       Role::Tiny - Roles: a nouvelle cuisine portion size slice of Moose
7

SYNOPSIS

9        package Some::Role;
10
11        use Role::Tiny;
12
13        sub foo { ... }
14
15        sub bar { ... }
16
17        around baz => sub { ... };
18
19        1;
20
21       elsewhere
22
23        package Some::Class;
24
25        use Role::Tiny::With;
26
27        # bar gets imported, but not foo
28        with 'Some::Role';
29
30        sub foo { ... }
31
32        # baz is wrapped in the around modifier by Class::Method::Modifiers
33        sub baz { ... }
34
35        1;
36
37       If you wanted attributes as well, look at Moo::Role.
38

DESCRIPTION

40       "Role::Tiny" is a minimalist role composition tool.
41

ROLE COMPOSITION

43       Role composition can be thought of as much more clever and meaningful
44       multiple inheritance.  The basics of this implementation of roles is:
45
46       • If a method is already defined on a class, that method will not be
47         composed in from the role. A method inherited by a class gets
48         overridden by the role's method of the same name, though.
49
50       • If a method that the role "requires" to be implemented is not
51         implemented, role application will fail loudly.
52
53       Unlike Class::C3, where the last class inherited from "wins," role
54       composition is the other way around, where the class wins. If multiple
55       roles are applied in a single call (single with statement), then if any
56       of their provided methods clash, an exception is raised unless the
57       class provides a method since this conflict indicates a potential
58       problem.
59
60   ROLE METHODS
61       All subs created after importing Role::Tiny will be considered methods
62       to be composed. For example:
63
64           package MyRole;
65           use List::Util qw(min);
66           sub mysub { }
67           use Role::Tiny;
68           use List::Util qw(max);
69           sub mymethod { }
70
71       In this role, "max" and "mymethod" will be included when composing
72       MyRole, and "min" and "mysub" will not. For additional control,
73       namespace::clean can be used to exclude undesired subs from roles.
74

IMPORTED SUBROUTINES

76   requires
77        requires qw(foo bar);
78
79       Declares a list of methods that must be defined to compose role.
80
81   with
82        with 'Some::Role1';
83
84        with 'Some::Role1', 'Some::Role2';
85
86       Composes another role into the current role (or class via
87       Role::Tiny::With).
88
89       If you have conflicts and want to resolve them in favour of Some::Role1
90       you can instead write:
91
92        with 'Some::Role1';
93        with 'Some::Role2';
94
95       If you have conflicts and want to resolve different conflicts in favour
96       of different roles, please refactor your codebase.
97
98   before
99        before foo => sub { ... };
100
101       See "before method(s) => sub { ... };" in Class::Method::Modifiers for
102       full documentation.
103
104       Note that since you are not required to use method modifiers,
105       Class::Method::Modifiers is lazily loaded and we do not declare it as a
106       dependency. If your Role::Tiny role uses modifiers you must depend on
107       both Class::Method::Modifiers and Role::Tiny.
108
109   around
110        around foo => sub { ... };
111
112       See "around method(s) => sub { ... };" in Class::Method::Modifiers for
113       full documentation.
114
115       Note that since you are not required to use method modifiers,
116       Class::Method::Modifiers is lazily loaded and we do not declare it as a
117       dependency. If your Role::Tiny role uses modifiers you must depend on
118       both Class::Method::Modifiers and Role::Tiny.
119
120   after
121        after foo => sub { ... };
122
123       See "after method(s) => sub { ... };" in Class::Method::Modifiers for
124       full documentation.
125
126       Note that since you are not required to use method modifiers,
127       Class::Method::Modifiers is lazily loaded and we do not declare it as a
128       dependency. If your Role::Tiny role uses modifiers you must depend on
129       both Class::Method::Modifiers and Role::Tiny.
130
131   Strict and Warnings
132       In addition to importing subroutines, using "Role::Tiny" applies strict
133       and warnings to the caller.
134

SUBROUTINES

136   does_role
137        if (Role::Tiny::does_role($foo, 'Some::Role')) {
138          ...
139        }
140
141       Returns true if class has been composed with role.
142
143       This subroutine is also installed as ->does on any class a Role::Tiny
144       is composed into unless that class already has an ->does method, so
145
146         if ($foo->does('Some::Role')) {
147           ...
148         }
149
150       will work for classes but to test a role, one must use ::does_role
151       directly.
152
153       Additionally, Role::Tiny will override the standard Perl "DOES" method
154       for your class. However, if "any" class in your class' inheritance
155       hierarchy provides "DOES", then Role::Tiny will not override it.
156

METHODS

158   make_role
159        Role::Tiny->make_role('Some::Role');
160
161       Makes a package into a role, but does not export any subs into it.
162
163   apply_roles_to_package
164        Role::Tiny->apply_roles_to_package(
165          'Some::Package', 'Some::Role', 'Some::Other::Role'
166        );
167
168       Composes role with package.  See also Role::Tiny::With.
169
170   apply_roles_to_object
171        Role::Tiny->apply_roles_to_object($foo, qw(Some::Role1 Some::Role2));
172
173       Composes roles in order into object directly. Object is reblessed into
174       the resulting class. Note that the object's methods get overridden by
175       the role's ones with the same names.
176
177   create_class_with_roles
178        Role::Tiny->create_class_with_roles('Some::Base', qw(Some::Role1 Some::Role2));
179
180       Creates a new class based on base, with the roles composed into it in
181       order.  New class is returned.
182
183   is_role
184        Role::Tiny->is_role('Some::Role1')
185
186       Returns true if the given package is a role.
187

CAVEATS

189       •   On perl 5.8.8 and earlier, applying a role to an object won't apply
190           any overloads from the role to other copies of the object.
191
192       •   On perl 5.16 and earlier, applying a role to a class won't apply
193           any overloads from the role to any existing instances of the class.
194

AUTHOR

203       mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>
204

CONTRIBUTORS

206       dg - David Leadbeater (cpan:DGL) <dgl@dgl.cx>
207
208       frew - Arthur Axel "fREW" Schmidt (cpan:FREW) <frioux@gmail.com>
209
210       hobbs - Andrew Rodland (cpan:ARODLAND) <arodland@cpan.org>
211
212       jnap - John Napiorkowski (cpan:JJNAPIORK) <jjn1056@yahoo.com>
213
214       ribasushi - Peter Rabbitson (cpan:RIBASUSHI) <ribasushi@cpan.org>
215
216       chip - Chip Salzenberg (cpan:CHIPS) <chip@pobox.com>
217
218       ajgb - Alex J. G. Burzyński (cpan:AJGB) <ajgb@cpan.org>
219
220       doy - Jesse Luehrs (cpan:DOY) <doy at tozt dot net>
221
222       perigrin - Chris Prather (cpan:PERIGRIN) <chris@prather.org>
223
224       Mithaldu - Christian Walde (cpan:MITHALDU)
225       <walde.christian@googlemail.com>
226
227       ilmari - Dagfinn Ilmari Mannsåker (cpan:ILMARI) <ilmari@ilmari.org>
228
229       tobyink - Toby Inkster (cpan:TOBYINK) <tobyink@cpan.org>
230
231       haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>
232

COPYRIGHT

234       Copyright (c) 2010-2012 the Role::Tiny "AUTHOR" and "CONTRIBUTORS" as
235       listed above.
236

LICENSE

238       This library is free software and may be distributed under the same
239       terms as perl itself.
240
241
242
243perl v5.34.0                      2022-01-21                     Role::Tiny(3)