NAME
Data::Object::Attributes
ABSTRACT
Attribute Builder for Perl 5
SYNOPSIS
package Example;
use Moo;
use Data::Object::Attributes;
has 'data';
package main;
my $example = Example->new;
DESCRIPTION
This package provides options for defining class attributes. Specifically, this package wraps the has
attribute keyword and adds shortcuts and enhancements. If no directives are specified, the attribute is declared as read-write
and optional
.
SCENARIOS
This package supports the following scenarios:
has
package Example::Has;
use Moo;
has 'data' => (
is => 'ro',
isa => sub { die }
);
package Example::HasData;
use Moo;
use Data::Object::Attributes;
extends 'Example::Has';
has '+data' => (
is => 'ro',
isa => sub { 1 }
);
package main;
my $example = Example::HasData->new(data => time);
This package supports the has
keyword function and all of its configurations. See the Moo documentation for more details.
has-bld
package Example::HasBld;
use Moo;
use routines;
use Data::Object::Attributes;
has data => (
is => 'ro',
bld => 1
);
method _build_data() {
return time;
}
package main;
my $example = Example::HasBld->new;
This package supports the bld
and builder
directives, expects a 1
, a method name, or coderef and builds the attribute value if it wasn't provided to the constructor. See the Moo documentation for more details.
has-clr
package Example::HasClr;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
clr => 1
);
package main;
my $example = Example::HasClr->new(data => time);
# $example->clear_data;
This package supports the clr
and clearer
directives expects a 1
or a method name of the clearer method. See the Moo documentation for more details.
has-crc
package Example::HasCrc;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
crc => sub {'0'}
);
package main;
my $example = Example::HasCrc->new(data => time);
This package supports the crc
and coerce
directives denotes whether an attribute's value should be automatically coerced. See the Moo documentation for more details.
has-def
package Example::HasDef;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
def => '0'
);
package main;
my $example = Example::HasDef->new;
This package supports the def
and default
directives expects a non-reference or a coderef to be used to build a default value if one is not provided to the constructor. See the Moo documentation for more details.
has-hnd
package Example::Time;
use Moo;
use routines;
method maketime() {
return time;
}
package Example::HasHnd;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
hnd => ['maketime']
);
package main;
my $example = Example::HasHnd->new(data => Example::Time->new);
This package supports the hnd
and handles
directives denotes the methods created on the object which dispatch to methods available on the attribute's object. See the Moo documentation for more details.
has-is
package Example::HasIs;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro'
);
package main;
my $example = Example::HasIs->new(data => time);
This package supports the is
directive, used to denote whether the attribute is read-only or read-write. See the Moo documentation for more details.
has-isa
package Example::HasIsa;
use Moo;
use registry;
use Data::Object::Attributes;
has data => (
is => 'ro',
isa => 'Str' # e.g. Types::Standard::Str
);
package main;
my $example = Example::HasIsa->new(data => time);
This package supports the isa
directive, used to define the type constraint to validate the attribute against. See the Moo documentation for more details.
has-lzy
package Example::HasLzy;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
def => sub {time},
lzy => 1
);
package main;
my $example = Example::HasLzy->new;
This package supports the lzy
and lazy
directives denotes whether the attribute will be constructed on-demand, or on-construction. See the Moo documentation for more details.
has-mod
package Example::HasNomod;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'rw',
opt => 1
);
package Example::HasMod;
use Moo;
use Data::Object::Attributes;
extends 'Example::HasNomod';
has data => (
is => 'ro',
req => 1,
mod => 1
);
package main;
my $example = Example::HasMod->new;
This package supports the mod
and modify
directives denotes whether a pre-existing attribute's definition is being modified. This ability is not supported by the Moo object superclass.
has-new
package Example::HasNew;
use Moo;
use routines;
use Data::Object::Attributes;
has data => (
is => 'ro',
new => 1
);
fun new_data($self) {
return time;
}
package main;
my $example = Example::HasNew->new(data => time);
This package supports the new
directive, if truthy, denotes that the attribute will be constructed on-demand, i.e. is lazy, with a builder named new_{attribute}. This ability is not supported by the Moo object superclass.
has-opt
package Example::HasOpt;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
opt => 1
);
package main;
my $example = Example::HasOpt->new(data => time);
This package supports the opt
and optional
directives, used to denote if an attribute is optional or required. See the Moo documentation for more details.
has-pre
package Example::HasPre;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
pre => 1
);
package main;
my $example = Example::HasPre->new(data => time);
This package supports the pre
and predicate
directives expects a 1
or a method name and generates a method for checking the existance of the attribute. See the Moo documentation for more details.
has-rdr
package Example::HasRdr;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
rdr => 'get_data'
);
package main;
my $example = Example::HasRdr->new(data => time);
This package supports the rdr
and reader
directives denotes the name of the method to be used to "read" and return the attribute's value. See the Moo documentation for more details.
has-req
package Example::HasReq;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
req => 1 # required
);
package main;
my $example = Example::HasReq->new(data => time);
This package supports the req
and required
directives, used to denote if an attribute is required or optional. See the Moo documentation for more details.
has-tgr
package Example::HasTgr;
use Moo;
use routines;
use Data::Object::Attributes;
has data => (
is => 'ro',
tgr => 1
);
method _trigger_data() {
$self->{triggered} = 1;
return $self;
}
package main;
my $example = Example::HasTgr->new(data => time);
This package supports the tgr
and trigger
directives expects a 1
or a coderef and is executed whenever the attribute's value is changed. See the Moo documentation for more details.
has-use
package Example::HasUse;
use Moo;
use routines;
use Data::Object::Attributes;
has data => (
is => 'ro',
use => ['service', 'time']
);
method service($type, @args) {
$self->{serviced} = 1;
return time if $type eq 'time';
}
package main;
my $example = Example::HasUse->new;
This package supports the use
directive denotes that the attribute will be constructed on-demand, i.e. is lazy, using a custom builder meant to perform service construction. This directive exists to provide a simple dependency injection mechanism for class attributes. This ability is not supported by the Moo object superclass.
has-wkr
package Example::HasWkr;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
wkr => 1
);
package main;
my $data = do {
my ($a, $b);
$a = { time => time };
$b = { time => $a };
$a->{time} = $b;
$a
};
my $example = Example::HasWkr->new(data => $data);
This package supports the wkr
and weak_ref
directives is used to denote if the attribute's value should be weakened. See the Moo documentation for more details.
has-wrt
package Example::HasWrt;
use Moo;
use Data::Object::Attributes;
has data => (
is => 'ro',
wrt => 'set_data'
);
package main;
my $example = Example::HasWrt->new;
This package supports the wrt
and writer
directives denotes the name of the method to be used to "write" and return the attribute's value. See the Moo documentation for more details.
AUTHOR
Al Newkirk, awncorp@cpan.org
LICENSE
Copyright (C) 2011-2019, Al Newkirk, et al.
This is free software; you can redistribute it and/or modify it under the terms of the The Apache License, Version 2.0, as elucidated in the "license file".