Commit | Line | Data |
0a6bff54 |
1 | package Moose::Meta::TypeConstraint::DuckType; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | use metaclass; |
6 | |
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7 | use Scalar::Util 'blessed'; |
0a6bff54 |
8 | use List::MoreUtils qw(all); |
9 | use Moose::Util 'english_list'; |
10 | |
11 | use Moose::Util::TypeConstraints (); |
12 | |
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13 | our $VERSION = '0.93'; |
0a6bff54 |
14 | $VERSION = eval $VERSION; |
15 | our $AUTHORITY = 'cpan:STEVAN'; |
16 | |
17 | use base 'Moose::Meta::TypeConstraint'; |
18 | |
19 | __PACKAGE__->meta->add_attribute('methods' => ( |
20 | accessor => 'methods', |
21 | )); |
22 | |
23 | sub new { |
24 | my ( $class, %args ) = @_; |
25 | |
26 | $args{parent} = Moose::Util::TypeConstraints::find_type_constraint('Object'); |
27 | |
28 | my $self = $class->_new(\%args); |
29 | |
30 | $self->compile_type_constraint() |
31 | unless $self->_has_compiled_type_constraint; |
32 | |
33 | return $self; |
34 | } |
35 | |
36 | sub equals { |
37 | my ( $self, $type_or_name ) = @_; |
38 | |
39 | my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name); |
40 | |
41 | return unless $other->isa(__PACKAGE__); |
42 | |
43 | my @self_methods = sort @{ $self->methods }; |
44 | my @other_methods = sort @{ $other->methods }; |
45 | |
46 | return unless @self_methods == @other_methods; |
47 | |
48 | while ( @self_methods ) { |
49 | my $method = shift @self_methods; |
50 | my $other_method = shift @other_methods; |
51 | |
52 | return unless $method eq $other_method; |
53 | } |
54 | |
55 | return 1; |
56 | } |
57 | |
58 | sub constraint { |
59 | my $self = shift; |
60 | |
61 | my @methods = @{ $self->methods }; |
62 | |
63 | return sub { |
64 | my $obj = shift; |
65 | return all { $obj->can($_) } @methods |
66 | }; |
67 | } |
68 | |
69 | sub _compile_hand_optimized_type_constraint { |
70 | my $self = shift; |
71 | |
72 | my @methods = @{ $self->methods }; |
73 | |
74 | sub { |
75 | my $obj = shift; |
76 | |
77 | return blessed($obj) |
78 | && blessed($obj) ne 'Regexp' |
79 | && all { $obj->can($_) } @methods; |
80 | }; |
81 | } |
82 | |
83 | sub create_child_type { |
84 | my ($self, @args) = @_; |
85 | return Moose::Meta::TypeConstraint->new(@args, parent => $self); |
86 | } |
87 | |
88 | sub get_message { |
89 | my $self = shift; |
90 | my ($value) = @_; |
91 | |
92 | if ($self->has_message) { |
93 | return $self->SUPER::get_message(@_); |
94 | } |
95 | |
96 | my @methods = grep { !$value->can($_) } @{ $self->methods }; |
97 | my $class = blessed $value; |
98 | return $class |
99 | . " is missing methods " |
100 | . english_list(map { "'$_'" } @methods); |
101 | } |
102 | |
103 | 1; |
104 | |
105 | __END__ |
106 | |
107 | =pod |
108 | |
109 | =head1 NAME |
110 | |
111 | Moose::Meta::TypeConstraint::DuckType - Type constraint for duck typing |
112 | |
113 | =head1 DESCRIPTION |
114 | |
115 | This class represents type constraints based on an enumerated list of |
116 | required methods. |
117 | |
118 | =head1 INHERITANCE |
119 | |
120 | C<Moose::Meta::TypeConstraint::DuckType> is a subclass of |
121 | L<Moose::Meta::TypeConstraint>. |
122 | |
123 | =head1 METHODS |
124 | |
125 | =over 4 |
126 | |
127 | =item B<< Moose::Meta::TypeConstraint::DuckType->new(%options) >> |
128 | |
129 | This creates a new duck type constraint based on the given |
130 | C<%options>. |
131 | |
132 | It takes the same options as its parent, with several |
133 | exceptions. First, it requires an additional option, C<methods>. This |
134 | should be an array reference containing a list of required method |
135 | names. Second, it automatically sets the parent to the C<Object> type. |
136 | |
137 | Finally, it ignores any provided C<constraint> option. The constraint |
138 | is generated automatically based on the provided C<methods>. |
139 | |
140 | =item B<< $constraint->methods >> |
141 | |
142 | Returns the array reference of required methods provided to the |
143 | constructor. |
144 | |
145 | =item B<< $constraint->create_child_type >> |
146 | |
147 | This returns a new L<Moose::Meta::TypeConstraint> object with the type |
148 | as its parent. |
149 | |
150 | Note that it does I<not> return a C<Moose::Meta::TypeConstraint::DuckType> |
151 | object! |
152 | |
153 | =back |
154 | |
155 | =head1 BUGS |
156 | |
157 | All complex software has bugs lurking in it, and this module is no |
158 | exception. If you find a bug please either email me, or add the bug |
159 | to cpan-RT. |
160 | |
161 | =head1 AUTHOR |
162 | |
163 | Chris Prather E<lt>chris@prather.orgE<gt> |
164 | |
165 | Shawn M Moore E<lt>sartak@gmail.comE<gt> |
166 | |
167 | =head1 COPYRIGHT AND LICENSE |
168 | |
169 | Copyright 2006-2009 by Infinity Interactive, Inc. |
170 | |
171 | L<http://www.iinteractive.com> |
172 | |
173 | This library is free software; you can redistribute it and/or modify |
174 | it under the same terms as Perl itself. |
175 | |
176 | =cut |
177 | |