Mouse::Role(3) User Contributed Perl Documentation Mouse::Role(3)NAMEMouse::Role - The Mouse Role
VERSION
This document describes Mouse version 1.02
SYNOPSIS
package Comparable;
use Mouse::Role; # the package is now a Mouse role
# Declare methods that are required by this role
requires qw(compare);
# Define methods this role provides
sub equals {
my($self, $other) = @_;
return $self->compare($other) == 0;
}
# and later
package MyObject;
use Mouse;
with qw(Comparable); # Now MyObject can equals()
sub compare {
# ...
}
my $foo = MyObject->new();
my $bar = MyObject->new();
$obj->equals($bar); # yes, it is comparable
DESCRIPTION
This module declares the caller class to be a Mouse role.
The concept of roles is documented in Moose::Manual::Roles. This
document serves as API documentation.
EXPORTED FUNCTIONSMouse::Role supports all of the functions that Mouse exports, but
differs slightly in how some items are handled (see "CAVEATS" below for
details).
Mouse::Role also offers two role-specific keywords:
"requires(@method_names)"
Roles can require that certain methods are implemented by any class
which "does" the role.
Note that attribute accessors also count as methods for the purposes of
satisfying the requirements of a role.
"excludes(@role_names)"
This is exported but not implemented in Mouse.
IMPORT AND UNIMPORT
import
Importing Mouse::Role will give you sugar. "-traits" are also
supported.
unimport
Please unimport ("no Mouse::Role") so that if someone calls one of the
keywords (such as "has") it will break loudly instead breaking subtly.
CAVEATS
Role support has only a few caveats:
· Roles cannot use the "extends" keyword; it will throw an exception
for now. The same is true of the "augment" and "inner" keywords
(not sure those really make sense for roles). All other Mouse
keywords will be deferred so that they can be applied to the
consuming class.
· Role composition does its best to not be order-sensitive when it
comes to conflict resolution and requirements detection. However,
it is order-sensitive when it comes to method modifiers. All
before/around/after modifiers are included whenever a role is
composed into a class, and then applied in the order in which the
roles are used. This also means that there is no conflict for
before/around/after modifiers.
In most cases, this will be a non-issue; however, it is something
to keep in mind when using method modifiers in a role. You should
never assume any ordering.
SEE ALSO
Mouse
Moose::Role
Moose::Manual::Roles
Moose::Spec::Role
perl v5.14.2 2012-08-27 Mouse::Role(3)
