1 package MooseX::Emulate::Class::Accessor::Fast;
7 use MooseX::Emulate::Class::Accessor::Fast::Meta::Accessor ();
9 our $VERSION = '0.00802';
13 MooseX::Emulate::Class::Accessor::Fast - Emulate Class::Accessor::Fast behavior using Moose attributes
20 with 'MooseX::Emulate::Class::Accessor::Fast';
23 #fields with readers and writers
24 __PACKAGE__->mk_accessors(qw/field1 field2/);
25 #fields with readers only
26 __PACKAGE__->mk_ro_accessors(qw/field3 field4/);
27 #fields with writers only
28 __PACKAGE__->mk_wo_accessors(qw/field5 field6/);
33 This module attempts to emulate the behavior of L<Class::Accessor::Fast> as
34 accurately as possible using the Moose attribute system. The public API of
35 C<Class::Accessor::Fast> is wholly supported, but the private methods are not.
36 If you are only using the public methods (as you should) migration should be a
37 matter of switching your C<use base> line to a C<with> line.
39 While I have attempted to emulate the behavior of Class::Accessor::Fast as closely
40 as possible bugs may still be lurking in edge-cases.
44 Simple documentation is provided here for your convenience, but for more thorough
45 documentation please see L<Class::Accessor::Fast> and L<Class::Accessor>.
47 =head2 A note about introspection
49 Please note that, at this time, the C<is> flag attribute is not being set. To
50 determine the C<reader> and C<writer> methods using introspection in later versions
51 of L<Class::MOP> ( > 0.38) please use the C<get_read_method> and C<get_write_method>
52 methods in L<Class::MOP::Attribute>. Example
54 # with Class::MOP <= 0.38
55 my $attr = $self->meta->find_attribute_by_name($field_name);
56 my $reader_method = $attr->reader || $attr->accessor;
57 my $writer_method = $attr->writer || $attr->accessor;
59 # with Class::MOP > 0.38
60 my $attr = $self->meta->find_attribute_by_name($field_name);
61 my $reader_method = $attr->get_read_method;
62 my $writer_method = $attr->get_write_method;
66 =head2 BUILD $self %args
68 Change the default Moose class building to emulate the behavior of C::A::F and
69 store arguments in the instance hashref.
73 my $locate_metaclass = sub {
74 my $class = Scalar::Util::blessed($_[0]) || $_[0];
75 return Class::MOP::get_metaclass_by_name($class)
76 || Moose::Meta::Class->initialize($class);
81 around 'BUILD' => sub {
84 my %args = %{ $_[0] };
86 my @extra = grep { !exists($self->{$_}) } keys %args;
87 @{$self}{@extra} = @args{@extra};
91 =head2 mk_accessors @field_names
93 Create read-write accessors. An attribute named C<$field_name> will be created.
94 The name of the c<reader> and C<writer> methods will be determined by the return
95 value of C<accessor_name_for> and C<mutator_name_for>, which by default return the
96 name passed unchanged. If the accessor and mutator names are equal the C<accessor>
97 attribute will be passes to Moose, otherwise the C<reader> and C<writer> attributes
98 will be passed. Please see L<Class::MOP::Attribute> for more information.
104 my $meta = $locate_metaclass->($self);
105 my $class = $meta->name;
106 confess("You are trying to modify ${class}, which has been made immutable, this is ".
107 "not supported. Try subclassing ${class}, rather than monkeypatching it")
108 if $meta->is_immutable;
110 for my $attr_name (@_){
111 $meta->remove_attribute($attr_name)
112 if $meta->find_attribute_by_name($attr_name);
113 my $reader = $self->accessor_name_for($attr_name);
114 my $writer = $self->mutator_name_for( $attr_name);
116 #dont overwrite existing methods
117 if($reader eq $writer){
118 my %opts = ( $meta->has_method($reader) ? () : (accessor => $reader) );
119 my $attr = $meta->find_attribute_by_name($attr_name) || $meta->add_attribute($attr_name, %opts,
120 traits => ['MooseX::Emulate::Class::Accessor::Fast::Meta::Role::Attribute']
122 if($attr_name eq $reader){
123 my $alias = "_${attr_name}_accessor";
124 next if $meta->has_method($alias);
125 $meta->add_method($alias => $attr->get_read_method_ref);
128 my @opts = ( $meta->has_method($writer) ? () : (writer => $writer) );
129 push(@opts, (reader => $reader)) unless $meta->has_method($reader);
130 my $attr = $meta->find_attribute_by_name($attr_name) || $meta->add_attribute($attr_name, @opts,
131 traits => ['MooseX::Emulate::Class::Accessor::Fast::Meta::Role::Attribute']
137 =head2 mk_ro_accessors @field_names
139 Create read-only accessors.
143 sub mk_ro_accessors {
145 my $meta = $locate_metaclass->($self);
146 my $class = $meta->name;
147 confess("You are trying to modify ${class}, which has been made immutable, this is ".
148 "not supported. Try subclassing ${class}, rather than monkeypatching it")
149 if $meta->is_immutable;
150 for my $attr_name (@_){
151 $meta->remove_attribute($attr_name)
152 if $meta->find_attribute_by_name($attr_name);
153 my $reader = $self->accessor_name_for($attr_name);
154 my @opts = ($meta->has_method($reader) ? () : (reader => $reader) );
155 my $attr = $meta->add_attribute($attr_name, @opts,
156 traits => ['MooseX::Emulate::Class::Accessor::Fast::Meta::Role::Attribute']
158 if($reader eq $attr_name && $reader eq $self->mutator_name_for($attr_name)){
159 $meta->add_method("_${attr_name}_accessor" => $attr->get_read_method_ref)
160 unless $meta->has_method("_${attr_name}_accessor");
165 =head2 mk_ro_accessors @field_names
167 Create write-only accessors.
171 #this is retarded.. but we need it for compatibility or whatever.
172 sub mk_wo_accessors {
174 my $meta = $locate_metaclass->($self);
175 my $class = $meta->name;
176 confess("You are trying to modify ${class}, which has been made immutable, this is ".
177 "not supported. Try subclassing ${class}, rather than monkeypatching it")
178 if $meta->is_immutable;
179 for my $attr_name (@_){
180 $meta->remove_attribute($attr_name)
181 if $meta->find_attribute_by_name($attr_name);
182 my $writer = $self->mutator_name_for($attr_name);
183 my @opts = ($meta->has_method($writer) ? () : (writer => $writer) );
184 my $attr = $meta->add_attribute($attr_name, @opts,
185 traits => ['MooseX::Emulate::Class::Accessor::Fast::Meta::Role::Attribute']
187 if($writer eq $attr_name && $writer eq $self->accessor_name_for($attr_name)){
188 $meta->add_method("_${attr_name}_accessor" => $attr->get_write_method_ref)
189 unless $meta->has_method("_${attr_name}_accessor");
194 =head2 follow_best_practices
196 Preface readers with 'get_' and writers with 'set_'.
197 See original L<Class::Accessor> documentation for more information.
201 sub follow_best_practice {
203 my $meta = $locate_metaclass->($self);
205 $meta->remove_method('mutator_name_for');
206 $meta->remove_method('accessor_name_for');
207 $meta->add_method('mutator_name_for', sub{ return "set_".$_[1] });
208 $meta->add_method('accessor_name_for', sub{ return "get_".$_[1] });
211 =head2 mutator_name_for
213 =head2 accessor_name_for
215 See original L<Class::Accessor> documentation for more information.
219 sub mutator_name_for { return $_[1] }
220 sub accessor_name_for { return $_[1] }
224 See original L<Class::Accessor> documentation for more information.
231 confess "Wrong number of arguments received" unless scalar @_;
232 my $meta = $locate_metaclass->($self);
234 confess "No such attribute '$k'"
235 unless ( my $attr = $meta->find_attribute_by_name($k) );
236 my $writer = $attr->get_write_method;
237 $self->$writer(@_ > 1 ? [@_] : @_);
242 See original L<Class::Accessor> documentation for more information.
248 confess "Wrong number of arguments received" unless scalar @_;
249 my $meta = $locate_metaclass->($self);
253 confess "No such attribute '$_'"
254 unless ( my $attr = $meta->find_attribute_by_name($_) );
255 my $reader = $attr->get_read_method;
256 @_ > 1 ? push(@values, $self->$reader) : return $self->$reader;
263 my($class, $field) = @_;
264 my $meta = $locate_metaclass->($class);
265 my $attr = $meta->find_attribute_by_name($field) || $meta->add_attribute($field,
266 traits => ['MooseX::Emulate::Class::Accessor::Fast::Meta::Role::Attribute']
268 my $reader = $attr->get_read_method_ref;
269 my $writer = $attr->get_write_method_ref;
272 return $reader->($self) unless @_;
273 return $writer->($self,(@_ > 1 ? [@_] : @_));
278 sub make_ro_accessor {
279 my($class, $field) = @_;
280 my $meta = $locate_metaclass->($class);
281 my $attr = $meta->find_attribute_by_name($field) || $meta->add_attribute($field,
282 traits => ['MooseX::Emulate::Class::Accessor::Fast::Meta::Role::Attribute']
284 return $attr->get_read_method_ref;
288 sub make_wo_accessor {
289 my($class, $field) = @_;
290 my $meta = $locate_metaclass->($class);
291 my $attr = $meta->find_attribute_by_name($field) || $meta->add_attribute($field,
292 traits => ['MooseX::Emulate::Class::Accessor::Fast::Meta::Role::Attribute']
294 return $attr->get_write_method_ref;
301 See L<Moose::Meta::Class>.
307 L<Moose>, L<Moose::Meta::Attribute>, L<Class::Accessor>, L<Class::Accessor::Fast>,
308 L<Class::MOP::Attribute>, L<MooseX::Adopt::Class::Accessor::Fast>
312 Guillermo Roditi (groditi) E<lt>groditi@cpan.orgE<gt>
314 With contributions from:
318 =item Tomas Doran (t0m) E<lt>bobtfish@bobtfish.netE<gt>
320 =item Florian Ragwitz (rafl) E<lt>rafl@debian.orgE<gt>
326 You may distribute this code under the same terms as Perl itself.