NAME

MooX::LazierAttributes - Lazier Attributes.

VERSION

Version 0.12

SYNOPSIS

    package Hello::World;
    
    use Moo;
    use MooX::LazierAttributes;

    attributes (
        one   => [], # defaults to be ro
        two   => [{}],
        three => [sub { My::Thing->new() }, { lzy, }],
        [qw/four five six/] => [rw, 'ruling the world'],
    );

    has seven => ( is_ro, lzy, default => sub { [qw/a b c/] });

    .....

    my $hello = Hello::World->new({ 
        one => 1,
        two => { three => 'four' },   
    });

    $hello->one;    # 1
    $hello->two;    # { three => 'four' }
    $hello->three;  # $obj

    ... Extending .....

    package Extends::Hello::World;

    use Moo;
    use MooX::LazierAttributes;

    extends 'Hello::World';
    
    attributes (
        '+one' => ['hey'],
        '+two' => [[qw/why are you inside/]],
        [qw/+four +five +six/] => ['well the sun it hurts my eyes'],
    );

    my $hello = Extends::Hello::World->new();

    $hello->one;    # hey
    $hello->twp;    # ['why', 'are', 'you', 'inside'],
    $hello->four;   # well the sun it hurts my eyes

    ... What if I like Types ...

    package Hello::World;
    
    use Moo;
    use MooX::LazierAttributes qw/is_ro rw lzy bld/;
    use Types::Standard qw/Str HashRef ArrayRef Object/;

    attributes (
        one   => [Str], # defaults to be ro
        two   => [HashRef],
        three => [Object, { lzy, bld }],
        [qw/four five six/] => [rw, Str, { default => 'ruling the world' }],
    );

    has seven => ( is_ro, lzy, isa => ArrayRef, default => sub { [qw/a b c/] });

    sub _build_three { 
        return My::Thing->new();
    }

EXPORT

attributes

I'm a list, my content gets transformed into Moo Attributes. My keys can either be a scalar or an array reference, they are used as the (*has*) name when constructing the Attributes.

    one => [],
    [qw/two three/] => []
    ...
    has one => ( is => 'ro' );
    has [qw/two three/] => ( is => 'ro' );

My value has to be an array reference, which can contain 3 indexes. If I was to write a read-write attribute that had a type constraint was lazy and also had a builder. It would look something like this.

    attribute (
        example => [ rw, ArrayRef, { lzy, bld } ],
    );
    
    ....
    
    has example => (
        is => 'rw',
        isa => ArrayRef,
        lazy => 1,
        builder => 1,
    );

The values first index - *is* - can only ever be ro/rw. A lot of the time you only actually want read-only so we can default that. I'll show you Another example this time we have a read-only attribute, that has a type constraint and is required.

    attributes (
        example => [ Str, { req } ]
    )
    
    ....
    
    has example => (
        is => 'ro',
        isa => Str,  
        required => 1,
    );

As you can see we have dropped the first index (*is*). The last index the [1] above and [2] in my first example must always be a hash reference that conforms to Moo attribute Standards. This module exports constants that try to make filling this reference less repetitive. Sometimes you may not always need extra, Moo Magic for example a read-only attribute with just a type constraint.

    attributes (
        example => [ArrayRef],
    );

    ....
    
    has example => (
        is => 'ro',
        isa => ArrayRef
    );

And just a read-only attribute...

    attributes (
        example => [],
    );

Constants

When you *use* MooX::LazierAttributes by default It will export the following constants. You can restrict which constants get imported the usual way you would with any other Exporter.

    use MooX::LazierAttributes qw/ro rw lzy bld/;

ro

'ro'

is_ro

( is => 'ro' )

rw

'rw'

is_rw

( is => 'rw' )

nan

undef

lzy;

( lazy => 1 )

bld

( builder => 1 )

lzy_bld

( lazy_build => 1 ),

trg

( tigger => 1 ),

req

( required => 1 ),

lzy_hash

( lazy => 1, default => sub { {} } )

lzy_array

( lazy => 1, default => sub { [] } )

Acknowledgements

One would like to Acknowledge Haarg for taking the time to read my code and pointing me in the right direction.

More than one way

You may also be interested in - MooseX::Has::Sugar.

AUTHOR

Robert Acock, <thisusedtobeanemail at gmail.com>

BUGS

Please report any bugs or feature requests to bug-moox-lazierattributes at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=MooX-LazierAttributes. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

    perldoc MooX::LazierAttributes

You can also look for information at:

• RT: CPAN's request tracker (report bugs here)

  http://rt.cpan.org/NoAuth/Bugs.html?Dist=MooX-LazierAttributes

• AnnoCPAN: Annotated CPAN documentation

  http://annocpan.org/dist/MooX-LazierAttributes

• CPAN Ratings

  http://cpanratings.perl.org/d/MooX-LazierAttributes

• Search CPAN

  http://search.cpan.org/dist/MooX-LazierAttributes/

ACKNOWLEDGEMENTS

LICENSE AND COPYRIGHT

Copyright 2017 Robert Acock.

This program is free software; you can redistribute it and/or modify it under the terms of the the Artistic License (2.0). You may obtain a copy of the full license at:

http://www.perlfoundation.org/artistic_license_2_0

Any use, modification, and distribution of the Standard or Modified Versions is governed by this Artistic License. By using, modifying or distributing the Package, you accept this license. Do not use, modify, or distribute the Package, if you do not accept this license.

If your Modified Version has been derived from a Modified Version made by someone other than you, you are nevertheless required to ensure that your Modified Version complies with the requirements of this license.

This license does not grant you the right to use any trademark, service mark, tradename, or logo of the Copyright Holder.

This license includes the non-exclusive, worldwide, free-of-charge patent license to make, have made, use, offer to sell, sell, import and otherwise transfer the Package with respect to any patent claims licensable by the Copyright Holder that are necessarily infringed by the Package. If you institute patent litigation (including a cross-claim or counterclaim) against any party alleging that the Package constitutes direct or contributory patent infringement, then this Artistic License to you shall terminate on the date that such litigation is filed.

Disclaimer of Warranty: THE PACKAGE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS "AS IS' AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES. THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT ARE DISCLAIMED TO THE EXTENT PERMITTED BY YOUR LOCAL LAW. UNLESS REQUIRED BY LAW, NO COPYRIGHT HOLDER OR CONTRIBUTOR WILL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING IN ANY WAY OUT OF THE USE OF THE PACKAGE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

cpanm MooX::LazierAttributes

perl -MCPAN -e shell
install MooX::LazierAttributes