Commit | Line | Data |
0a6bff54 |
1 | package Moose::Meta::TypeConstraint::DuckType; |
2 | |
3 | use strict; |
4 | use warnings; |
5 | use metaclass; |
6 | |
7 | use List::MoreUtils qw(all); |
8 | use Moose::Util 'english_list'; |
9 | |
10 | use Moose::Util::TypeConstraints (); |
11 | |
9039e8ec |
12 | our $VERSION = '0.89_01'; |
0a6bff54 |
13 | $VERSION = eval $VERSION; |
14 | our $AUTHORITY = 'cpan:STEVAN'; |
15 | |
16 | use base 'Moose::Meta::TypeConstraint'; |
17 | |
18 | __PACKAGE__->meta->add_attribute('methods' => ( |
19 | accessor => 'methods', |
20 | )); |
21 | |
22 | sub new { |
23 | my ( $class, %args ) = @_; |
24 | |
25 | $args{parent} = Moose::Util::TypeConstraints::find_type_constraint('Object'); |
26 | |
27 | my $self = $class->_new(\%args); |
28 | |
29 | $self->compile_type_constraint() |
30 | unless $self->_has_compiled_type_constraint; |
31 | |
32 | return $self; |
33 | } |
34 | |
35 | sub equals { |
36 | my ( $self, $type_or_name ) = @_; |
37 | |
38 | my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name); |
39 | |
40 | return unless $other->isa(__PACKAGE__); |
41 | |
42 | my @self_methods = sort @{ $self->methods }; |
43 | my @other_methods = sort @{ $other->methods }; |
44 | |
45 | return unless @self_methods == @other_methods; |
46 | |
47 | while ( @self_methods ) { |
48 | my $method = shift @self_methods; |
49 | my $other_method = shift @other_methods; |
50 | |
51 | return unless $method eq $other_method; |
52 | } |
53 | |
54 | return 1; |
55 | } |
56 | |
57 | sub constraint { |
58 | my $self = shift; |
59 | |
60 | my @methods = @{ $self->methods }; |
61 | |
62 | return sub { |
63 | my $obj = shift; |
64 | return all { $obj->can($_) } @methods |
65 | }; |
66 | } |
67 | |
68 | sub _compile_hand_optimized_type_constraint { |
69 | my $self = shift; |
70 | |
71 | my @methods = @{ $self->methods }; |
72 | |
73 | sub { |
74 | my $obj = shift; |
75 | |
76 | return blessed($obj) |
77 | && blessed($obj) ne 'Regexp' |
78 | && all { $obj->can($_) } @methods; |
79 | }; |
80 | } |
81 | |
82 | sub create_child_type { |
83 | my ($self, @args) = @_; |
84 | return Moose::Meta::TypeConstraint->new(@args, parent => $self); |
85 | } |
86 | |
87 | sub get_message { |
88 | my $self = shift; |
89 | my ($value) = @_; |
90 | |
91 | if ($self->has_message) { |
92 | return $self->SUPER::get_message(@_); |
93 | } |
94 | |
95 | my @methods = grep { !$value->can($_) } @{ $self->methods }; |
96 | my $class = blessed $value; |
97 | return $class |
98 | . " is missing methods " |
99 | . english_list(map { "'$_'" } @methods); |
100 | } |
101 | |
102 | 1; |
103 | |
104 | __END__ |
105 | |
106 | =pod |
107 | |
108 | =head1 NAME |
109 | |
110 | Moose::Meta::TypeConstraint::DuckType - Type constraint for duck typing |
111 | |
112 | =head1 DESCRIPTION |
113 | |
114 | This class represents type constraints based on an enumerated list of |
115 | required methods. |
116 | |
117 | =head1 INHERITANCE |
118 | |
119 | C<Moose::Meta::TypeConstraint::DuckType> is a subclass of |
120 | L<Moose::Meta::TypeConstraint>. |
121 | |
122 | =head1 METHODS |
123 | |
124 | =over 4 |
125 | |
126 | =item B<< Moose::Meta::TypeConstraint::DuckType->new(%options) >> |
127 | |
128 | This creates a new duck type constraint based on the given |
129 | C<%options>. |
130 | |
131 | It takes the same options as its parent, with several |
132 | exceptions. First, it requires an additional option, C<methods>. This |
133 | should be an array reference containing a list of required method |
134 | names. Second, it automatically sets the parent to the C<Object> type. |
135 | |
136 | Finally, it ignores any provided C<constraint> option. The constraint |
137 | is generated automatically based on the provided C<methods>. |
138 | |
139 | =item B<< $constraint->methods >> |
140 | |
141 | Returns the array reference of required methods provided to the |
142 | constructor. |
143 | |
144 | =item B<< $constraint->create_child_type >> |
145 | |
146 | This returns a new L<Moose::Meta::TypeConstraint> object with the type |
147 | as its parent. |
148 | |
149 | Note that it does I<not> return a C<Moose::Meta::TypeConstraint::DuckType> |
150 | object! |
151 | |
152 | =back |
153 | |
154 | =head1 BUGS |
155 | |
156 | All complex software has bugs lurking in it, and this module is no |
157 | exception. If you find a bug please either email me, or add the bug |
158 | to cpan-RT. |
159 | |
160 | =head1 AUTHOR |
161 | |
162 | Chris Prather E<lt>chris@prather.orgE<gt> |
163 | |
164 | Shawn M Moore E<lt>sartak@gmail.comE<gt> |
165 | |
166 | =head1 COPYRIGHT AND LICENSE |
167 | |
168 | Copyright 2006-2009 by Infinity Interactive, Inc. |
169 | |
170 | L<http://www.iinteractive.com> |
171 | |
172 | This library is free software; you can redistribute it and/or modify |
173 | it under the same terms as Perl itself. |
174 | |
175 | =cut |
176 | |