Commit | Line | Data |
5447ee45 |
1 | package MooseX::UndefTolerant; |
5447ee45 |
2 | |
3 | use Moose qw(); |
4 | use Moose::Exporter; |
5447ee45 |
5 | |
6 | use MooseX::UndefTolerant::Attribute; |
2d1c57bd |
7 | use MooseX::UndefTolerant::Constructor; |
5447ee45 |
8 | |
779ca481 |
9 | our $VERSION = '0.04'; |
5447ee45 |
10 | |
e92df8d4 |
11 | Moose::Exporter->setup_import_methods( |
2d1c57bd |
12 | class_metaroles => { |
13 | attribute => [ 'MooseX::UndefTolerant::Attribute' ], |
14 | constructor => [ 'MooseX::UndefTolerant::Constructor' ], |
15 | } |
e92df8d4 |
16 | ); |
5447ee45 |
17 | |
18 | 1; |
19 | |
20 | __END__ |
21 | |
22 | =head1 NAME |
23 | |
d0abfb45 |
24 | MooseX::UndefTolerant - Make your attribute(s) tolerant to undef initialization |
5447ee45 |
25 | |
26 | =head1 SYNOPSIS |
27 | |
19258058 |
28 | package My::Class; |
5447ee45 |
29 | |
19258058 |
30 | use Moose; |
31 | use MooseX::UndefTolerant; |
32 | |
33 | has 'name' => ( |
34 | is => 'ro', |
35 | isa => 'Str', |
36 | predicate => 'has_name' |
37 | ); |
38 | |
39 | # Meanwhile, under the city... |
40 | |
41 | # Doesn't explode |
42 | my $class = My::Class->new(name => undef); |
43 | $class->has_name # False! |
44 | |
45 | Or, if you only want one attribute to have this behaviour: |
46 | |
47 | package My:Class; |
48 | use Moose; |
49 | |
50 | use MooseX::UndefTolerant::Attribute; |
51 | |
52 | has 'bar' => ( |
53 | traits => [ qw(MooseX::UndefTolerant::Attribute)], |
54 | is => 'ro', |
55 | isa => 'Num', |
56 | predicate => 'has_bar' |
57 | ); |
58 | |
59 | =head1 DESCRIPTION |
60 | |
61 | Loading this module in your L<Moose> class makes initialization of your |
62 | attributes tolerant of undef. If you specify the value of undef to any of |
63 | the attributes they will not be initialized. Effectively behaving as if you |
64 | had not provided a value at all. |
65 | |
66 | =head1 MOTIVATION |
67 | |
68 | I often found myself in this quandry: |
69 | |
70 | package My:Class; |
71 | use Moose; |
72 | |
73 | has 'foo' => ( |
74 | is => 'ro', |
75 | isa => 'Str', |
76 | ); |
77 | |
78 | # ... then |
79 | |
80 | my $foo = ... # get the param from something |
81 | |
82 | my $class = My:Class->new(foo => $foo, bar => 123); |
83 | |
84 | What if foo is undefined? I didn't want to change my attribute to be |
85 | Maybe[Str] and I still want my predicate (C<has_foo>) to work. The only |
86 | real solution was: |
87 | |
88 | if(defined($foo)) { |
1cbb963b |
89 | $class = My:Class->new(foo => $foo, bar => 123); |
19258058 |
90 | } else { |
1cbb963b |
91 | $class = My:Class->new(bar => 123); |
19258058 |
92 | } |
93 | |
94 | Or some type of codemulch using ternarys. This module allows you to make |
95 | your attributes more tolerant of undef so that you can keep the first |
96 | example: have your cake and eat it too! |
97 | |
98 | =head1 PER ATTRIBUTE |
5447ee45 |
99 | |
1cbb963b |
100 | See L<MooseX::UndefTolerant::Attribute>. |
101 | |
5447ee45 |
102 | =head1 AUTHOR |
103 | |
104 | Cory G Watson, C<< <gphat at cpan.org> >> |
105 | |
106 | =head1 ACKNOWLEDGEMENTS |
107 | |
19258058 |
108 | Many thanks to the crew in #moose who talked me through this module: |
109 | |
5447ee45 |
110 | Hans Dieter Pearcey (confound) |
111 | |
112 | Jesse Luehrs (doy) |
113 | |
114 | Tomas Doran (t0m) |
115 | |
116 | Dylan Hardison (dylan) |
117 | |
118 | Jay Shirley (jshirley) |
119 | |
120 | Mike Eldridge (diz) |
121 | |
122 | =head1 COPYRIGHT & LICENSE |
123 | |
124 | Copyright 2009 Cory G Watson. |
125 | |
126 | This program is free software; you can redistribute it and/or modify it |
127 | under the terms of either: the GNU General Public License as published |
128 | by the Free Software Foundation; or the Artistic License. |
129 | |
130 | See http://dev.perl.org/licenses/ for more information. |
131 | |
5447ee45 |
132 | =cut |