Commit | Line | Data |
5cf3dbcf |
1 | |
2 | package Moose::Meta::Method::Constructor; |
3 | |
4 | use strict; |
5 | use warnings; |
6 | |
7 | use Carp 'confess'; |
8 | use Scalar::Util 'blessed', 'weaken', 'looks_like_number'; |
9 | |
10 | our $VERSION = '0.01'; |
11 | our $AUTHORITY = 'cpan:STEVAN'; |
12 | |
13 | use base 'Moose::Meta::Method'; |
14 | |
15 | sub new { |
16 | my $class = shift; |
17 | my %options = @_; |
18 | |
19 | (exists $options{options} && ref $options{options} eq 'HASH') |
20 | || confess "You must pass a hash of options"; |
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21 | |
22 | my $self = bless { |
23 | # from our superclass |
24 | '&!body' => undef, |
25 | # specific to this subclass |
26 | '%!options' => $options{options}, |
587ae0d2 |
27 | '$!meta_instance' => $options{metaclass}->get_meta_instance, |
28 | '@!attributes' => [ $options{metaclass}->compute_all_applicable_attributes ], |
5cf3dbcf |
29 | # ... |
30 | '$!associated_metaclass' => $options{metaclass}, |
31 | } => $class; |
32 | |
33 | # we don't want this creating |
34 | # a cycle in the code, if not |
35 | # needed |
5cf3dbcf |
36 | weaken($self->{'$!associated_metaclass'}); |
37 | |
38 | $self->intialize_body; |
39 | |
40 | return $self; |
41 | } |
42 | |
43 | ## accessors |
44 | |
45 | sub options { (shift)->{'%!options'} } |
46 | sub meta_instance { (shift)->{'$!meta_instance'} } |
47 | sub attributes { (shift)->{'@!attributes'} } |
48 | |
49 | sub associated_metaclass { (shift)->{'$!associated_metaclass'} } |
50 | |
51 | ## method |
52 | |
53 | sub intialize_body { |
54 | my $self = shift; |
55 | # TODO: |
56 | # the %options should also include a both |
57 | # a call 'initializer' and call 'SUPER::' |
58 | # options, which should cover approx 90% |
59 | # of the possible use cases (even if it |
60 | # requires some adaption on the part of |
61 | # the author, after all, nothing is free) |
62 | my $source = 'sub {'; |
1f779926 |
63 | $source .= "\n" . 'my $class = shift;'; |
64 | |
587ae0d2 |
65 | $source .= "\n" . 'return $class->Moose::Object::new(@_)'; |
1f779926 |
66 | $source .= "\n" . ' if $class ne \'' . $self->associated_metaclass->name . '\';'; |
67 | |
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68 | $source .= "\n" . 'my %params = (scalar @_ == 1) ? %{$_[0]} : @_;'; |
69 | |
70 | $source .= "\n" . 'my $instance = ' . $self->meta_instance->inline_create_instance('$class'); |
71 | |
72 | $source .= ";\n" . (join ";\n" => map { |
73 | $self->_generate_slot_initializer($_) |
74 | } 0 .. (@{$self->attributes} - 1)); |
75 | |
76 | $source .= ";\n" . $self->_generate_BUILDALL(); |
77 | |
78 | $source .= ";\n" . 'return $instance'; |
79 | $source .= ";\n" . '}'; |
80 | warn $source if $self->options->{debug}; |
81 | |
82 | my $code; |
83 | { |
84 | # NOTE: |
85 | # create the nessecary lexicals |
86 | # to be picked up in the eval |
87 | my $attrs = $self->attributes; |
88 | |
89 | $code = eval $source; |
90 | confess "Could not eval the constructor :\n\n$source\n\nbecause :\n\n$@" if $@; |
91 | } |
92 | $self->{'&!body'} = $code; |
93 | } |
94 | |
95 | sub _generate_BUILDALL { |
96 | my $self = shift; |
97 | my @BUILD_calls; |
1f779926 |
98 | foreach my $method (reverse $self->associated_metaclass->find_all_methods_by_name('BUILD')) { |
8ecb1fa0 |
99 | push @BUILD_calls => '$instance->' . $method->{class} . '::BUILD(\%params)'; |
5cf3dbcf |
100 | } |
101 | return join "\n" => @BUILD_calls; |
102 | } |
103 | |
104 | sub _generate_slot_initializer { |
105 | my $self = shift; |
106 | my $index = shift; |
107 | |
108 | my $attr = $self->attributes->[$index]; |
109 | |
110 | my @source = ('## ' . $attr->name); |
111 | |
112 | if ($attr->is_required && !$attr->has_default) { |
113 | push @source => ('(exists $params{\'' . $attr->init_arg . '\'}) ' . |
114 | '|| confess "Attribute (' . $attr->name . ') is required";'); |
115 | } |
116 | |
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117 | if ($attr->has_default && !$attr->is_lazy) { |
118 | |
8ecb1fa0 |
119 | push @source => 'if (exists $params{\'' . $attr->init_arg . '\'}) {'; |
120 | |
121 | push @source => ('my $val = $params{\'' . $attr->init_arg . '\'};'); |
122 | if ($attr->has_type_constraint) { |
123 | push @source => ('my $type_constraint = $attrs->[' . $index . ']->type_constraint;'); |
124 | |
125 | if ($attr->should_coerce && $attr->type_constraint->has_coercion) { |
126 | push @source => $self->_generate_type_coercion($attr, '$type_constraint', '$val', '$val'); |
127 | } |
128 | push @source => $self->_generate_type_constraint_check($attr, '$type_constraint', '$val'); |
129 | } |
130 | push @source => $self->_generate_slot_assignment($attr, '$val'); |
131 | |
132 | |
5cf3dbcf |
133 | push @source => "} else {"; |
134 | |
135 | my $default = $self->_generate_default_value($attr, $index); |
136 | |
137 | push @source => ('my $val = ' . $default . ';'); |
138 | push @source => $self->_generate_type_constraint_check( |
139 | $attr, |
140 | ('$attrs->[' . $index . ']->type_constraint'), |
141 | '$val' |
142 | ) if $attr->has_type_constraint; |
143 | push @source => $self->_generate_slot_assignment($attr, $default); |
144 | |
145 | push @source => "}"; |
146 | } |
147 | else { |
8ecb1fa0 |
148 | push @source => '(exists $params{\'' . $attr->init_arg . '\'}) && do {'; |
149 | |
150 | push @source => ('my $val = $params{\'' . $attr->init_arg . '\'};'); |
151 | if ($attr->has_type_constraint) { |
152 | push @source => ('my $type_constraint = $attrs->[' . $index . ']->type_constraint;'); |
153 | |
154 | if ($attr->should_coerce && $attr->type_constraint->has_coercion) { |
155 | push @source => $self->_generate_type_coercion($attr, '$type_constraint', '$val', '$val'); |
156 | } |
157 | push @source => $self->_generate_type_constraint_check($attr, '$type_constraint', '$val'); |
158 | } |
159 | push @source => $self->_generate_slot_assignment($attr, '$val'); |
160 | |
5cf3dbcf |
161 | push @source => "}"; |
162 | } |
163 | |
164 | return join "\n" => @source; |
165 | } |
166 | |
167 | sub _generate_slot_assignment { |
168 | my ($self, $attr, $value) = @_; |
169 | my $source = ( |
170 | $self->meta_instance->inline_set_slot_value( |
171 | '$instance', |
172 | ("'" . $attr->name . "'"), |
173 | $value |
174 | ) . ';' |
175 | ); |
176 | |
177 | if ($attr->is_weak_ref) { |
178 | $source .= ( |
179 | "\n" . |
180 | $self->meta_instance->inline_weaken_slot_value( |
181 | '$instance', |
182 | ("'" . $attr->name . "'") |
183 | ) . |
184 | ' if ref ' . $value . ';' |
185 | ); |
186 | } |
187 | |
188 | return $source; |
189 | } |
190 | |
191 | sub _generate_type_coercion { |
192 | my ($self, $attr, $type_constraint_name, $value_name, $return_value_name) = @_; |
193 | return ($return_value_name . ' = ' . $type_constraint_name . '->coerce(' . $value_name . ');'); |
194 | } |
195 | |
196 | sub _generate_type_constraint_check { |
197 | my ($self, $attr, $type_constraint_name, $value_name) = @_; |
198 | return ( |
199 | 'defined(' . $type_constraint_name . '->_compiled_type_constraint->(' . $value_name . '))' |
200 | . "\n\t" . '|| confess "Attribute (' . $attr->name . ') does not pass the type constraint (' |
201 | . $attr->type_constraint->name . ') with " . (defined() ? "' . $value_name . '" : "undef");' |
202 | ); |
203 | } |
204 | |
205 | sub _generate_default_value { |
206 | my ($self, $attr, $index) = @_; |
207 | # NOTE: |
208 | # default values can either be CODE refs |
209 | # in which case we need to call them. Or |
210 | # they can be scalars (strings/numbers) |
211 | # in which case we can just deal with them |
212 | # in the code we eval. |
213 | if ($attr->is_default_a_coderef) { |
214 | return '$attrs->[' . $index . ']->default($instance)'; |
215 | } |
216 | else { |
217 | my $default = $attr->default; |
218 | # make sure to quote strings ... |
219 | unless (looks_like_number($default)) { |
220 | $default = "'$default'"; |
221 | } |
222 | |
223 | return $default; |
224 | } |
225 | } |
226 | |
227 | 1; |
228 | |
229 | 1; |
230 | |
231 | __END__ |
232 | |
233 | =pod |
234 | |
235 | =head1 NAME |
236 | |
237 | Moose::Meta::Method::Constructor - Method Meta Object for constructors |
238 | |
5cf3dbcf |
239 | =head1 DESCRIPTION |
240 | |
d44714be |
241 | This is a subclass of L<Class::MOP::Method> which handles |
242 | constructing an approprate Constructor methods. This is primarily |
243 | used in the making of immutable metaclasses, otherwise it is |
244 | not particularly useful. |
245 | |
5cf3dbcf |
246 | =head1 METHODS |
247 | |
248 | =over 4 |
249 | |
250 | =item B<new> |
251 | |
252 | =item B<attributes> |
253 | |
254 | =item B<meta_instance> |
255 | |
256 | =item B<options> |
257 | |
258 | =item B<intialize_body> |
259 | |
260 | =item B<associated_metaclass> |
261 | |
262 | =back |
263 | |
264 | =head1 AUTHORS |
265 | |
266 | Stevan Little E<lt>stevan@iinteractive.comE<gt> |
267 | |
268 | =head1 COPYRIGHT AND LICENSE |
269 | |
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270 | Copyright 2006, 2007 by Infinity Interactive, Inc. |
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271 | |
272 | L<http://www.iinteractive.com> |
273 | |
274 | This library is free software; you can redistribute it and/or modify |
275 | it under the same terms as Perl itself. |
276 | |
277 | =cut |
278 | |