2 package Class::MOP::Method::Constructor;
8 use Scalar::Util 'blessed', 'weaken', 'looks_like_number';
10 our $VERSION = '0.94';
11 $VERSION = eval $VERSION;
12 our $AUTHORITY = 'cpan:STEVAN';
14 use base 'Class::MOP::Method::Inlined';
20 (blessed $options{metaclass} && $options{metaclass}->isa('Class::MOP::Class'))
21 || confess "You must pass a metaclass instance if you want to inline"
22 if $options{is_inline};
24 ($options{package_name} && $options{name})
25 || confess "You must supply the package_name and name parameters $Class::MOP::Method::UPGRADE_ERROR_TEXT";
27 my $self = $class->_new(\%options);
29 # we don't want this creating
30 # a cycle in the code, if not
32 weaken($self->{'associated_metaclass'});
34 $self->_initialize_body;
42 return Class::MOP::Class->initialize($class)->new_object(@_)
43 if $class ne __PACKAGE__;
45 my $params = @_ == 1 ? $_[0] : {@_};
48 # inherited from Class::MOP::Method
49 body => $params->{body},
50 # associated_metaclass => $params->{associated_metaclass}, # overriden
51 package_name => $params->{package_name},
52 name => $params->{name},
53 original_method => $params->{original_method},
55 # inherited from Class::MOP::Generated
56 is_inline => $params->{is_inline} || 0,
57 definition_context => $params->{definition_context},
59 # inherited from Class::MOP::Inlined
60 _expected_method_class => $params->{_expected_method_class},
62 # defined in this subclass
63 options => $params->{options} || {},
64 associated_metaclass => $params->{metaclass},
70 sub options { (shift)->{'options'} }
71 sub associated_metaclass { (shift)->{'associated_metaclass'} }
77 $self->{'meta_instance'} ||= $self->associated_metaclass->get_meta_instance;
82 $self->{'attributes'} ||= [ $self->associated_metaclass->get_all_attributes ]
87 sub _initialize_body {
89 my $method_name = '_generate_constructor_method';
91 $method_name .= '_inline' if $self->is_inline;
93 $self->{'body'} = $self->$method_name;
96 sub _generate_constructor_method {
97 return sub { Class::MOP::Class->initialize(shift)->new_object(@_) }
100 sub _generate_constructor_method_inline {
105 my $source = 'sub {';
106 $source .= "\n" . 'my $class = shift;';
108 $source .= "\n" . 'return Class::MOP::Class->initialize($class)->new_object(@_)';
109 $source .= "\n" . ' if $class ne \'' . $self->associated_metaclass->name . '\';';
111 $source .= "\n" . 'my $params = @_ == 1 ? $_[0] : {@_};';
113 $source .= "\n" . 'my $instance = ' . $self->_meta_instance->inline_create_instance('$class');
114 $source .= ";\n" . (join ";\n" => map {
115 $self->_generate_slot_initializer($_, $close_over)
116 } @{ $self->_attributes });
117 $source .= ";\n" . 'return $instance';
118 $source .= ";\n" . '}';
119 warn $source if $self->options->{debug};
121 my ( $code, $e ) = $self->_eval_closure(
125 confess "Could not eval the constructor :\n\n$source\n\nbecause :\n\n$e" if $e;
130 sub _generate_slot_initializer {
136 if ($attr->has_default) {
138 # default values can either be CODE refs
139 # in which case we need to call them. Or
140 # they can be scalars (strings/numbers)
141 # in which case we can just deal with them
142 # in the code we eval.
143 if ($attr->is_default_a_coderef) {
144 my $idx = @{$close->{'@defaults'}||=[]};
145 push(@{$close->{'@defaults'}}, $attr->default);
146 $default = '$defaults[' . $idx . ']->($instance)';
149 $default = $attr->default;
150 # make sure to quote strings ...
151 unless (looks_like_number($default)) {
152 $default = "'$default'";
155 } elsif( $attr->has_builder ) {
156 $default = '$instance->'.$attr->builder;
159 if ( defined(my $init_arg = $attr->init_arg) ) {
161 'if(exists $params->{\'' . $init_arg . '\'}){' . "\n" .
162 $self->_meta_instance->inline_set_slot_value(
165 '$params->{\'' . $init_arg . '\'}' ) . "\n" .
166 '} ' . (!defined $default ? '' : 'else {' . "\n" .
167 $self->_meta_instance->inline_set_slot_value(
173 } elsif ( defined $default ) {
175 $self->_meta_instance->inline_set_slot_value(
191 Class::MOP::Method::Constructor - Method Meta Object for constructors
195 use Class::MOP::Method::Constructor;
197 my $constructor = Class::MOP::Method::Constructor->new(
198 metaclass => $metaclass,
200 debug => 1, # this is all for now
204 # calling the constructor ...
205 $constructor->body->execute($metaclass->name, %params);
209 This is a subclass of C<Class::MOP::Method> which generates
216 =item B<< Class::MOP::Method::Constructor->new(%options) >>
218 This creates a new constructor object. It accepts a hash reference of
225 This should be a L<Class::MOP::Class> object. It is required.
229 The method name (without a package name). This is required.
233 The package name for the method. This is required.
237 This indicates whether or not the constructor should be inlined. This
242 =item B<< $metamethod->is_inline >>
244 Returns a boolean indicating whether or not the constructor is
247 =item B<< $metamethod->associated_metaclass >>
249 This returns the L<Class::MOP::Class> object for the method.
255 Stevan Little E<lt>stevan@iinteractive.comE<gt>
257 =head1 COPYRIGHT AND LICENSE
259 Copyright 2006-2009 by Infinity Interactive, Inc.
261 L<http://www.iinteractive.com>
263 This library is free software; you can redistribute it and/or modify
264 it under the same terms as Perl itself.