use Scalar::Util 'blessed', 'weaken', 'reftype';
use Carp 'confess';
-our $VERSION = '0.05';
+our $VERSION = '0.10';
+our $AUTHORITY = 'cpan:STEVAN';
+use Moose::Meta::Method::Accessor;
use Moose::Util::TypeConstraints ();
use base 'Class::MOP::Attribute';
+# options which are not directly used
+# but we store them for metadata purposes
+__PACKAGE__->meta->add_attribute('isa' => (reader => '_isa_metadata'));
+__PACKAGE__->meta->add_attribute('does' => (reader => '_does_metadata'));
+__PACKAGE__->meta->add_attribute('is' => (reader => '_is_metadata'));
+
+# these are actual options for the attrs
__PACKAGE__->meta->add_attribute('required' => (reader => 'is_required' ));
__PACKAGE__->meta->add_attribute('lazy' => (reader => 'is_lazy' ));
__PACKAGE__->meta->add_attribute('coerce' => (reader => 'should_coerce' ));
reader => 'trigger',
predicate => 'has_trigger',
));
+__PACKAGE__->meta->add_attribute('handles' => (
+ reader => 'handles',
+ predicate => 'has_handles',
+));
+__PACKAGE__->meta->add_attribute('documentation' => (
+ reader => 'documentation',
+ predicate => 'has_documentation',
+));
sub new {
my ($class, $name, %options) = @_;
$class->_process_options($name, \%options);
- $class->SUPER::new($name, %options);
+ return $class->SUPER::new($name, %options);
}
sub clone_and_inherit_options {
my ($self, %options) = @_;
- # you can change default, required and coerce
+ # you can change default, required, coerce and documentation
my %actual_options;
- foreach my $legal_option (qw(default coerce required)) {
+ foreach my $legal_option (qw(default coerce required documentation)) {
if (exists $options{$legal_option}) {
$actual_options{$legal_option} = $options{$legal_option};
delete $options{$legal_option};
(defined $type_constraint)
|| confess "Could not find the type constraint '" . $options{isa} . "'";
}
+ # NOTE:
+ # check here to see if the new type
+ # is a subtype of the old one
($type_constraint->is_subtype_of($self->type_constraint->name))
|| confess "New type constraint setting must be a subtype of inherited one"
+ # iff we have a type constraint that is ...
if $self->has_type_constraint;
+ # then we use it :)
$actual_options{type_constraint} = $type_constraint;
delete $options{isa};
}
sub _process_options {
my ($class, $name, $options) = @_;
+
if (exists $options->{is}) {
if ($options->{is} eq 'ro') {
- $options->{reader} = $name;
+ $options->{reader} ||= $name;
(!exists $options->{trigger})
|| confess "Cannot have a trigger on a read-only attribute";
}
elsif ($options->{is} eq 'rw') {
- $options->{accessor} = $name;
- ((reftype($options->{trigger}) || '') eq 'CODE')
- || confess "A trigger must be a CODE reference"
- if exists $options->{trigger};
+ $options->{accessor} = $name;
+ ((reftype($options->{trigger}) || '') eq 'CODE')
+ || confess "Trigger must be a CODE ref"
+ if exists $options->{trigger};
+ }
+ else {
+ confess "I do not understand this option (is => " . $options->{is} . ")"
}
}
if (exists $options->{coerce} && $options->{coerce}) {
(exists $options->{type_constraint})
- || confess "You cannot have coercion without specifying a type constraint";
- (!$options->{type_constraint}->isa('Moose::Meta::TypeConstraint::Union'))
- || confess "You cannot have coercion with a type constraint union";
+ || confess "You cannot have coercion without specifying a type constraint";
confess "You cannot have a weak reference to a coerced value"
if $options->{weak_ref};
}
+ if (exists $options->{auto_deref} && $options->{auto_deref}) {
+ (exists $options->{type_constraint})
+ || confess "You cannot auto-dereference without specifying a type constraint";
+ ($options->{type_constraint}->is_a_type_of('ArrayRef') ||
+ $options->{type_constraint}->is_a_type_of('HashRef'))
+ || confess "You cannot auto-dereference anything other than a ArrayRef or HashRef";
+ }
+
if (exists $options->{lazy} && $options->{lazy}) {
(exists $options->{default})
|| confess "You cannot have lazy attribute without specifying a default value for it";
if (!defined $val && $self->has_default) {
$val = $self->default($instance);
}
+
if (defined $val) {
if ($self->has_type_constraint) {
my $type_constraint = $self->type_constraint;
if ($self->should_coerce && $type_constraint->has_coercion) {
- $val = $type_constraint->coercion->coerce($val);
+ $val = $type_constraint->coerce($val);
}
(defined($type_constraint->check($val)))
|| confess "Attribute (" .
$self->name .
- ") does not pass the type contraint (" .
+ ") does not pass the type constraint (" .
$type_constraint->name .
") with '$val'";
}
if ref $val && $self->is_weak_ref;
}
-sub _inline_check_constraint {
- my ($self, $value) = @_;
- return '' unless $self->has_type_constraint;
-
- # FIXME - remove 'unless defined($value) - constraint Undef
- return sprintf <<'EOF', $value, $value, $value, $value
-defined($attr->type_constraint->check(%s))
- || confess "Attribute (" . $attr->name . ") does not pass the type contraint ("
- . $attr->type_constraint->name . ") with " . (defined(%s) ? "'%s'" : "undef")
- if defined(%s);
-EOF
-}
-
-sub _inline_store {
- my ($self, $instance, $value) = @_;
+## Slot management
- my $mi = $self->associated_class->get_meta_instance;
- my $slot_name = sprintf "'%s'", $self->slots;
-
- my $code = $mi->inline_set_slot_value($instance, $slot_name, $value) . ";";
- $code .= $mi->inline_weaken_slot_value($instance, $slot_name, $value) . ";"
- if $self->is_weak_ref;
- return $code;
+sub set_value {
+ my ($self, $instance, $value) = @_;
+
+ my $attr_name = $self->name;
+
+ if ($self->is_required) {
+ defined($value)
+ || confess "Attribute ($attr_name) is required, so cannot be set to undef";
+ }
+
+ if ($self->has_type_constraint) {
+
+ my $type_constraint = $self->type_constraint;
+
+ if ($self->should_coerce) {
+ $value = $type_constraint->coerce($value);
+ }
+ defined($type_constraint->_compiled_type_constraint->($value))
+ || confess "Attribute ($attr_name) does not pass the type constraint ("
+ . $type_constraint->name . ") with " . (defined($value) ? ("'" . $value . "'") : "undef")
+ if defined($value);
+ }
+
+ my $meta_instance = Class::MOP::Class->initialize(blessed($instance))
+ ->get_meta_instance;
+
+ $meta_instance->set_slot_value($instance, $attr_name, $value);
+
+ if (ref $value && $self->is_weak_ref) {
+ $meta_instance->weaken_slot_value($instance, $attr_name);
+ }
+
+ if ($self->has_trigger) {
+ $self->trigger->($instance, $value, $self);
+ }
}
-sub _inline_trigger {
- my ($self, $instance, $value) = @_;
- return '' unless $self->has_trigger;
- return sprintf('$attr->trigger->(%s, %s, $attr);', $instance, $value);
+sub get_value {
+ my ($self, $instance) = @_;
+
+ if ($self->is_lazy) {
+ unless ($self->has_value($instance)) {
+ if ($self->has_default) {
+ my $default = $self->default($instance);
+ $self->set_value($instance, $default);
+ }
+ else {
+ $self->set_value($instance, undef);
+ }
+ }
+ }
+
+ if ($self->should_auto_deref) {
+
+ my $type_constraint = $self->type_constraint;
+
+ if ($type_constraint->is_a_type_of('ArrayRef')) {
+ my $rv = $self->SUPER::get_value($instance);
+ return unless defined $rv;
+ return wantarray ? @{ $rv } : $rv;
+ }
+ elsif ($type_constraint->is_a_type_of('HashRef')) {
+ my $rv = $self->SUPER::get_value($instance);
+ return unless defined $rv;
+ return wantarray ? %{ $rv } : $rv;
+ }
+ else {
+ confess "Can not auto de-reference the type constraint '" . $type_constraint->name . "'";
+ }
+
+ }
+ else {
+
+ return $self->SUPER::get_value($instance);
+ }
}
-sub _inline_get {
- my ($self, $instance) = @_;
+## installing accessors
- my $mi = $self->associated_class->get_meta_instance;
- my $slot_name = sprintf "'%s'", $self->slots;
+sub accessor_metaclass { 'Moose::Meta::Method::Accessor' }
- return $mi->inline_get_slot_value($instance, $slot_name);
+sub install_accessors {
+ my $self = shift;
+ $self->SUPER::install_accessors(@_);
+
+ if ($self->has_handles) {
+
+ # NOTE:
+ # Here we canonicalize the 'handles' option
+ # this will sort out any details and always
+ # return an hash of methods which we want
+ # to delagate to, see that method for details
+ my %handles = $self->_canonicalize_handles();
+
+ # find the name of the accessor for this attribute
+ my $accessor_name = $self->reader || $self->accessor;
+ (defined $accessor_name)
+ || confess "You cannot install delegation without a reader or accessor for the attribute";
+
+ # make sure we handle HASH accessors correctly
+ ($accessor_name) = keys %{$accessor_name}
+ if ref($accessor_name) eq 'HASH';
+
+ # install the delegation ...
+ my $associated_class = $self->associated_class;
+ foreach my $handle (keys %handles) {
+ my $method_to_call = $handles{$handle};
+
+ (!$associated_class->has_method($handle))
+ || confess "You cannot overwrite a locally defined method ($handle) with a delegation";
+
+ # NOTE:
+ # handles is not allowed to delegate
+ # any of these methods, as they will
+ # override the ones in your class, which
+ # is almost certainly not what you want.
+ next if $handle =~ /^BUILD|DEMOLISH$/ || Moose::Object->can($handle);
+
+ if ((reftype($method_to_call) || '') eq 'CODE') {
+ $associated_class->add_method($handle => $method_to_call);
+ }
+ else {
+ $associated_class->add_method($handle => sub {
+ # FIXME
+ # we should check for lack of
+ # a callable return value from
+ # the accessor here
+ ((shift)->$accessor_name())->$method_to_call(@_);
+ });
+ }
+ }
+ }
+
+ return;
}
-sub _inline_auto_deref {
- my ( $self, $ref_value ) = @_;
+# private methods to help delegation ...
- return $ref_value unless $self->should_auto_deref;
-
- my $type = eval { $self->type_constraint->name } || '';
- my $sigil;
-
- if ( $type eq "ArrayRef" ) {
- $sigil = '@';
- } elsif ( $type eq 'HashRef' ) {
- $sigil = '%';
- } else {
- confess "Can't auto deref unless type constraint is ArrayRef or HashRef";
+sub _canonicalize_handles {
+ my $self = shift;
+ my $handles = $self->handles;
+ if (ref($handles) eq 'HASH') {
+ return %{$handles};
+ }
+ elsif (ref($handles) eq 'ARRAY') {
+ return map { $_ => $_ } @{$handles};
+ }
+ elsif (ref($handles) eq 'Regexp') {
+ ($self->has_type_constraint)
+ || confess "Cannot delegate methods based on a RegExpr without a type constraint (isa)";
+ return map { ($_ => $_) }
+ grep { /$handles/ } $self->_get_delegate_method_list;
+ }
+ elsif (ref($handles) eq 'CODE') {
+ return $handles->($self, $self->_find_delegate_metaclass);
+ }
+ else {
+ confess "Unable to canonicalize the 'handles' option with $handles";
}
-
- "(wantarray() ? $sigil\{ ( $ref_value ) || return } : ( $ref_value ) )";
-}
-
-sub generate_accessor_method {
- my ($attr, $attr_name) = @_;
- my $value_name = $attr->should_coerce ? '$val' : '$_[1]';
- my $mi = $attr->associated_class->get_meta_instance;
- my $slot_name = sprintf "'%s'", $attr->slots;
- my $inv = '$_[0]';
- my $code = 'sub { '
- . 'if (scalar(@_) == 2) {'
- . ($attr->is_required ?
- 'defined($_[1]) || confess "Attribute ($attr_name) is required, so cannot be set to undef";'
- : '')
- . ($attr->should_coerce ?
- 'my $val = $attr->type_constraint->coercion->coerce($_[1]);'
- : '')
- . $attr->_inline_check_constraint($value_name)
- . $attr->_inline_store($inv, $value_name)
- . $attr->_inline_trigger($inv, $value_name)
- . ' }'
- . ($attr->is_lazy ?
- '$_[0]->{$attr_name} = ($attr->has_default ? $attr->default($_[0]) : undef)'
- . 'unless exists $_[0]->{$attr_name};'
- : '')
- . 'return ' . $attr->_inline_auto_deref( $attr->_inline_get( $inv ) )
- . ' }';
- my $sub = eval $code;
- warn "Could not create accessor for '$attr_name' because $@ \n code: $code" if $@;
- confess "Could not create accessor for '$attr_name' because $@ \n code: $code" if $@;
- return $sub;
}
-sub generate_writer_method {
- my ($attr, $attr_name) = @_;
- my $value_name = $attr->should_coerce ? '$val' : '$_[1]';
- my $inv = '$_[0]';
- my $code = 'sub { '
- . ($attr->is_required ?
- 'defined($_[1]) || confess "Attribute ($attr_name) is required, so cannot be set to undef";'
- : '')
- . ($attr->should_coerce ?
- 'my $val = $attr->type_constraint->coercion->coerce($_[1]);'
- : '')
- . $attr->_inline_check_constraint($value_name)
- . $attr->_inline_store($inv, $value_name)
- . $attr->_inline_trigger($inv, $value_name)
- . ' }';
- my $sub = eval $code;
- confess "Could not create writer for '$attr_name' because $@ \n code: $code" if $@;
- return $sub;
+sub _find_delegate_metaclass {
+ my $self = shift;
+ if (my $class = $self->_isa_metadata) {
+ # if the class does have
+ # a meta method, use it
+ return $class->meta if $class->can('meta');
+ # otherwise we might be
+ # dealing with a non-Moose
+ # class, and need to make
+ # our own metaclass
+ return Moose::Meta::Class->initialize($class);
+ }
+ elsif (my $role = $self->_does_metadata) {
+ # our role will always have
+ # a meta method
+ return $role->meta;
+ }
+ else {
+ confess "Cannot find delegate metaclass for attribute " . $self->name;
+ }
}
-sub generate_reader_method {
+sub _get_delegate_method_list {
my $self = shift;
- my $attr_name = $self->slots;
- my $code = 'sub {'
- . 'confess "Cannot assign a value to a read-only accessor" if @_ > 1;'
- . ($self->is_lazy ?
- '$_[0]->{$attr_name} = ($self->has_default ? $self->default($_[0]) : undef)'
- . 'unless exists $_[0]->{$attr_name};'
- : '')
- . 'return ' . $self->_inline_auto_deref( '$_[0]->{$attr_name}' ) . ';'
- . '}';
- my $sub = eval $code;
- confess "Could not create reader for '$attr_name' because $@ \n code: $code" if $@;
- return $sub;
+ my $meta = $self->_find_delegate_metaclass;
+ if ($meta->isa('Class::MOP::Class')) {
+ return map { $_->{name} } # NOTE: !never! delegate &meta
+ grep { $_->{class} ne 'Moose::Object' && $_->{name} ne 'meta' }
+ $meta->compute_all_applicable_methods;
+ }
+ elsif ($meta->isa('Moose::Meta::Role')) {
+ return $meta->get_method_list;
+ }
+ else {
+ confess "Unable to recognize the delegate metaclass '$meta'";
+ }
}
1;
=item B<new>
-=item B<clone_and_inherit_options>
-
=item B<initialize_instance_slot>
-=item B<generate_accessor_method>
+=item B<install_accessors>
-=item B<generate_writer_method>
+=item B<accessor_metaclass>
-=item B<generate_reader_method>
+=item B<get_value>
+
+=item B<set_value>
=back
=head2 Additional Moose features
-Moose attributes support type-contstraint checking, weak reference
+Moose attributes support type-constraint checking, weak reference
creation and type coercion.
=over 4
+=item B<clone_and_inherit_options>
+
+This is to support the C<has '+foo'> feature, it clones an attribute
+from a superclass and allows a very specific set of changes to be made
+to the attribute.
+
=item B<has_type_constraint>
Returns true if this meta-attribute has a type constraint.
more information on what you can do with this, see the documentation
for L<Moose::Meta::TypeConstraint>.
+=item B<has_handles>
+
+Returns true if this meta-attribute performs delegation.
+
+=item B<handles>
+
+This returns the value which was passed into the handles option.
+
=item B<is_weak_ref>
Returns true if this meta-attribute produces a weak reference.
Returns true if this meta-attribute should perform type coercion.
+=item B<should_auto_deref>
+
+Returns true if this meta-attribute should perform automatic
+auto-dereferencing.
+
+NOTE: This can only be done for attributes whose type constraint is
+either I<ArrayRef> or I<HashRef>.
+
=item B<has_trigger>
Returns true if this meta-attribute has a trigger set.
the invocant and the new value. This can be used to handle I<basic>
bi-directional relations.
+=item B<documentation>
+
+This is a string which contains the documentation for this attribute.
+It serves no direct purpose right now, but it might in the future
+in some kind of automated documentation system perhaps.
+
+=item B<has_documentation>
+
+Returns true if this meta-attribute has any documentation.
+
=back
=head1 BUGS
Stevan Little E<lt>stevan@iinteractive.comE<gt>
+Yuval Kogman E<lt>nothingmuch@woobling.comE<gt>
+
=head1 COPYRIGHT AND LICENSE
-Copyright 2006 by Infinity Interactive, Inc.
+Copyright 2006, 2007 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
projects / gitmo/Moose.git / blobdiff