# NAME
MooX::Role::Parameterized - roles with composition parameters
[](https://cpants.cpanauthors.org/dist/MooX-Role-Parameterized)
[](https://github.com/peczenyj/MooX-Role-Parameterized/actions/workflows/linux.yml)
[](https://github.com/peczenyj/MooX-Role-Parameterized/actions/workflows/windows.yml)
[](https://github.com/peczenyj/MooX-Role-Parameterized/actions/workflows/macos.yml)
[](https://github.com/peczenyj/MooX-Role-Parameterized/actions/workflows/perltidy.yml)
[](https://github.com/peczenyj/MooX-Role-Parameterized/actions/workflows/perlcritic.yml)
[](https://coveralls.io/github/peczenyj/MooX-Role-Parameterized?branch=master)
[](https://github.com/peczenyj/MooX-Role-Parameterized/blob/master/LICENSE)
[](https://metacpan.org/dist/MooX-Role-Parameterized)
## SYNOPSIS
package Counter;
use Moo::Role;
use MooX::Role::Parameterized;
use Types::Standard qw( Str );
parameter name => (
is => 'ro', # this is mandatory on Moo
isa => Str, # optional type
required => 1, # mark the parameter "name" as "required"
);
role {
my ( $p, $mop ) = @_;
my $name = $p->name; # $p->{name} will also work
$mop->has($name => (
is => 'rw',
default => sub { 0 },
));
$mop->method("increment_$name" => sub {
my $self = shift;
$self->$name($self->$name + 1);
});
$mop->method("reset_$name" => sub {
my $self = shift;
$self->$name(0);
});
};
package MyGame::Weapon;
use Moo;
use MooX::Role::Parameterized::With;
with Counter => { # injects 'enchantment' attribute and
name => 'enchantment', # methods increment_enchantment (+1)
}; # reset_enchantment (set to zero)
package MyGame::Wand;
use Moo;
use MooX::Role::Parameterized::With;
with Counter => { # injects 'zapped' attribute and
name => 'zapped', # methods increment_zapped (+1)
}; # reset_zapped (set to zerà )
## DESCRIPTION
It is an **experimental** port of [MooseX::Role::Parameterized](https://metacpan.org/pod/MooseX::Role::Parameterized) to [Moo](https://metacpan.org/pod/Moo).
## FUNCTIONS
This package exports the following subroutines: `parameter`, `role`, `apply_roles_to_target` and `apply`.
### parameter
This function receive the same parameter as `Moo::has`. If present, the parameter hash reference will be blessed as a Moo class. This is useful to add default values or set some parameters as required.
### role
This function accepts just **one** code block. Will execute this code then we apply the Role in the
target class and will receive the parameter hash reference + one **mop** object.
The **params** reference will be blessed if there is some parameter defined on this role.
The **mop** object is a proxy to the target class.
It offer a better way to call `has`, `after`, `before`, `around`, `with` and `requires` without side effects.
Use `method` to inject a new method and `meta` to access `TARGET_PACKAGE->meta`
Please use:
my ($p, $mop) = @_;
...
$mop->has($p->{attribute} =>(...));
$mop->method(name => sub { ... });
$mop->meta->make_immutable;
### apply
Alias to `apply_roles_to_target`.
### apply_roles_to_target
When called, will apply the `/role` on the current package. The behavior depends of the parameter list.
This will install the role in the target package. Does not need call `with`.
Important, if you want to apply the role multiple times, like to create multiple attributes, please pass an **arrayref**.
package My::Role;
use Moo::Role;
use MooX::Role::Parameterized;
role {
my ($params, $mop) = @_;
$mop->has( $params->{attr} => ( is => 'rw' ));
$mop->method($params->{method} => sub {
1024;
});
};
package My::Class;
use Moo;
use My::Role;
My::Role->apply_roles_to_target([{ # original way of add this role
attr => 'baz', # add attribute read-write called 'baz'
method => 'run' # add method called 'run' and return 1024
}
, # and if the apply receives one arrayref
{ attr => 'bam', # will call the role block multiple times.
method => 'jump' # PLEASE CALL apply once
}]);
## MooX::Role::Parameterized::VERBOSE
By setting `$MooX::Role::Parameterized::VERBOSE` with some true value we will carp on certain conditions
(method override, unable to load package, etc).
Default is false.
## DEPRECATED FUNCTIONS
### hasp
Deleted
### method
Deleted
## MooX::Role::Parameterized::With
See [MooX::Role::Parameterized::With](https://metacpan.org/pod/MooX::Role::Parameterized::With) package to easily load and apply roles.
## SEE ALSO
[MooseX::Role::Parameterized](https://metacpan.org/pod/MooseX::Role::Parameterized) - Moose version
## THANKS
* FGA <fabrice.gabolde@gmail.com>
* PERLANCAR <perlancar@gmail.com>
* CHOROBA <choroba@cpan.org>
* Ed J <mohawk2@users.noreply.github.com>
## LICENSE
The MIT License
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated
documentation files (the "Software"), to deal in the Software
without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to
whom the Software is furnished to do so, subject to the
following conditions:
The above copyright notice and this permission notice shall
be included in all copies or substantial portions of the
Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT
WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE AND NONINFRINGEMENT. IN NO EVENT
SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
## AUTHOR
Tiago Peczenyj <tiago (dot) peczenyj (at) gmail (dot) com>
## BUGS
Please report any bugs or feature requests on the bugtracker website