use Scalar::Util 'blessed', 'weaken', 'reftype';
use Carp 'confess';
+use Sub::Name 'subname';
+use overload ();
-our $VERSION = '0.06';
+our $VERSION = '0.18';
+our $AUTHORITY = 'cpan:STEVAN';
+use Moose::Meta::Method::Accessor;
use Moose::Util::TypeConstraints ();
use base 'Class::MOP::Attribute';
# these are actual options for the attrs
__PACKAGE__->meta->add_attribute('required' => (reader => 'is_required' ));
__PACKAGE__->meta->add_attribute('lazy' => (reader => 'is_lazy' ));
+__PACKAGE__->meta->add_attribute('lazy_build' => (reader => 'is_lazy_build' ));
__PACKAGE__->meta->add_attribute('coerce' => (reader => 'should_coerce' ));
__PACKAGE__->meta->add_attribute('weak_ref' => (reader => 'is_weak_ref' ));
__PACKAGE__->meta->add_attribute('auto_deref' => (reader => 'should_auto_deref'));
reader => 'handles',
predicate => 'has_handles',
));
+__PACKAGE__->meta->add_attribute('documentation' => (
+ reader => 'documentation',
+ predicate => 'has_documentation',
+));
sub new {
- my ($class, $name, %options) = @_;
- $class->_process_options($name, \%options);
- return $class->SUPER::new($name, %options);
+ my ($class, $name, %options) = @_;
+ $class->_process_options($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, documentation and lazy
my %actual_options;
- foreach my $legal_option (qw(default coerce required)) {
+ foreach my $legal_option (qw(default coerce required documentation lazy)) {
if (exists $options{$legal_option}) {
$actual_options{$legal_option} = $options{$legal_option};
delete $options{$legal_option};
}
}
- # isa can be changed, but only if the
- # new type is a subtype
+
+ # handles can only be added, not changed
+ if ($options{handles}) {
+ confess "You can only add the 'handles' option, you cannot change it"
+ if $self->has_handles;
+ $actual_options{handles} = $options{handles};
+ delete $options{handles};
+ }
+
+ # isa can be changed, but only if the
+ # new type is a subtype
if ($options{isa}) {
my $type_constraint;
- if (blessed($options{isa}) && $options{isa}->isa('Moose::Meta::TypeConstraint')) {
- $type_constraint = $options{isa};
- }
- else {
- $type_constraint = Moose::Util::TypeConstraints::find_type_constraint($options{isa});
- (defined $type_constraint)
- || confess "Could not find the type constraint '" . $options{isa} . "'";
- }
- ($type_constraint->is_subtype_of($self->type_constraint->name))
- || confess "New type constraint setting must be a subtype of inherited one"
- if $self->has_type_constraint;
- $actual_options{type_constraint} = $type_constraint;
+ if (blessed($options{isa}) && $options{isa}->isa('Moose::Meta::TypeConstraint')) {
+ $type_constraint = $options{isa};
+ }
+ else {
+ $type_constraint = Moose::Util::TypeConstraints::find_or_create_type_constraint(
+ $options{isa}
+ );
+ (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};
}
- (scalar keys %options == 0)
+ (scalar keys %options == 0)
|| confess "Illegal inherited options => (" . (join ', ' => keys %options) . ")";
$self->clone(%actual_options);
}
sub _process_options {
my ($class, $name, $options) = @_;
-
- if (exists $options->{is}) {
- if ($options->{is} eq 'ro') {
- $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 "Trigger must be a CODE ref"
- if exists $options->{trigger};
- }
- else {
- confess "I do not understand this option (is => " . $options->{is} . ")"
- }
- }
-
- if (exists $options->{isa}) {
-
- if (exists $options->{does}) {
- if (eval { $options->{isa}->can('does') }) {
- ($options->{isa}->does($options->{does}))
- || confess "Cannot have an isa option and a does option if the isa does not do the does";
- }
- else {
- confess "Cannot have an isa option which cannot ->does()";
- }
- }
-
- # allow for anon-subtypes here ...
- if (blessed($options->{isa}) && $options->{isa}->isa('Moose::Meta::TypeConstraint')) {
- $options->{type_constraint} = $options->{isa};
- }
- else {
-
- if ($options->{isa} =~ /\|/) {
- my @type_constraints = split /\s*\|\s*/ => $options->{isa};
- $options->{type_constraint} = Moose::Util::TypeConstraints::create_type_constraint_union(
- @type_constraints
- );
- }
- else {
- # otherwise assume it is a constraint
- my $constraint = Moose::Util::TypeConstraints::find_type_constraint($options->{isa});
- # if the constraing it not found ....
- unless (defined $constraint) {
- # assume it is a foreign class, and make
- # an anon constraint for it
- $constraint = Moose::Util::TypeConstraints::subtype(
- 'Object',
- Moose::Util::TypeConstraints::where { $_->isa($options->{isa}) }
- );
- }
- $options->{type_constraint} = $constraint;
+
+ if (exists $options->{is}) {
+ if ($options->{is} eq 'ro') {
+ $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 "Trigger must be a CODE ref"
+ if exists $options->{trigger};
+ }
+ else {
+ confess "I do not understand this option (is => " . $options->{is} . ")"
+ }
+ }
+
+ if (exists $options->{isa}) {
+ if (exists $options->{does}) {
+ if (eval { $options->{isa}->can('does') }) {
+ ($options->{isa}->does($options->{does}))
+ || confess "Cannot have an isa option and a does option if the isa does not do the does";
}
- }
- }
- elsif (exists $options->{does}) {
- # allow for anon-subtypes here ...
- if (blessed($options->{does}) && $options->{does}->isa('Moose::Meta::TypeConstraint')) {
- $options->{type_constraint} = $options->{isa};
- }
- else {
- # otherwise assume it is a constraint
- my $constraint = Moose::Util::TypeConstraints::find_type_constraint($options->{does});
- # if the constraing it not found ....
- unless (defined $constraint) {
- # assume it is a foreign class, and make
- # an anon constraint for it
- $constraint = Moose::Util::TypeConstraints::subtype(
- 'Role',
- Moose::Util::TypeConstraints::where { $_->does($options->{does}) }
- );
- }
- $options->{type_constraint} = $constraint;
- }
- }
-
- 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";
+ else {
+ confess "Cannot have an isa option which cannot ->does()";
+ }
+ }
+
+ # allow for anon-subtypes here ...
+ if (blessed($options->{isa}) && $options->{isa}->isa('Moose::Meta::TypeConstraint')) {
+ $options->{type_constraint} = $options->{isa};
+ }
+ else {
+ $options->{type_constraint} = Moose::Util::TypeConstraints::find_or_create_type_constraint(
+ $options->{isa} => {
+ parent => Moose::Util::TypeConstraints::find_type_constraint('Object'),
+ constraint => sub { $_[0]->isa($options->{isa}) }
+ }
+ );
+ }
+ }
+ elsif (exists $options->{does}) {
+ # allow for anon-subtypes here ...
+ if (blessed($options->{does}) && $options->{does}->isa('Moose::Meta::TypeConstraint')) {
+ $options->{type_constraint} = $options->{does};
+ }
+ else {
+ $options->{type_constraint} = Moose::Util::TypeConstraints::find_or_create_type_constraint(
+ $options->{does} => {
+ parent => Moose::Util::TypeConstraints::find_type_constraint('Role'),
+ constraint => sub {
+ Moose::Util::does_role($_[0], $options->{does})
+ }
+ }
+ );
+ }
+ }
+
+ if (exists $options->{coerce} && $options->{coerce}) {
+ (exists $options->{type_constraint})
+ || 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}->name =~ /^ArrayRef|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 $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_build} && $options->{lazy_build} == 1) {
+ confess("You can not use lazy_build and default for the same attribute")
+ if exists $options->{default};
+ $options->{lazy} = 1;
+ $options->{required} = 1;
+ $options->{builder} ||= "_build_${name}";
+ if ($name =~ /^_/) {
+ $options->{clearer} ||= "_clear${name}";
+ $options->{predicate} ||= "_has${name}";
+ }
+ else {
+ $options->{clearer} ||= "clear_${name}";
+ $options->{predicate} ||= "has_${name}";
+ }
+ }
+
+ if (exists $options->{lazy} && $options->{lazy}) {
+ (exists $options->{default} || exists $options->{builder} )
+ || confess "You cannot have lazy attribute without specifying a default value for it";
+ }
+
}
sub initialize_instance_slot {
my $init_arg = $self->init_arg();
# try to fetch the init arg from the %params ...
- my $val;
+ my $val;
+ my $value_is_set;
if (exists $params->{$init_arg}) {
$val = $params->{$init_arg};
+ $value_is_set = 1;
}
else {
# skip it if it's lazy
return if $self->is_lazy;
# and die if it's required and doesn't have a default value
- confess "Attribute (" . $self->name . ") is required"
- if $self->is_required && !$self->has_default;
+ confess "Attribute (" . $self->name . ") is required"
+ if $self->is_required && !$self->has_default && !$self->has_builder;
+
+ # if nothing was in the %params, we can use the
+ # attribute's default value (if it has one)
+ if ($self->has_default) {
+ $val = $self->default($instance);
+ $value_is_set = 1;
+ }
+ elsif ($self->has_builder) {
+ if (my $builder = $instance->can($self->builder)){
+ $val = $instance->$builder;
+ $value_is_set = 1;
+ }
+ else {
+ confess(blessed($instance)." does not support builder method '".$self->builder."' for attribute '" . $self->name . "'");
+ }
+ }
}
- # if nothing was in the %params, we can use the
- # attribute's default value (if it has one)
- 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);
- }
- (defined($type_constraint->check($val)))
- || confess "Attribute (" .
- $self->name .
- ") does not pass the type constraint (" .
- $type_constraint->name .
- ") with '$val'";
+ return unless $value_is_set;
+
+ if ($self->has_type_constraint) {
+ my $type_constraint = $self->type_constraint;
+ if ($self->should_coerce && $type_constraint->has_coercion) {
+ $val = $type_constraint->coerce($val);
}
- }
+ (defined($type_constraint->check($val)))
+ || confess "Attribute (" .
+ $self->name .
+ ") does not pass the type constraint (" .
+ $type_constraint->name .
+ ") with '" .
+ (defined $val
+ ? overload::StrVal($val)
+ : 'undef') .
+ "'";
+ }
$meta_instance->set_slot_value($instance, $self->name, $val);
- $meta_instance->weaken_slot_value($instance, $self->name)
+ $meta_instance->weaken_slot_value($instance, $self->name)
if ref $val && $self->is_weak_ref;
}
-## Accessor inline subroutines
-
-sub _inline_check_constraint {
- my ($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 constraint ("
- . $attr->type_constraint->name . ") with " . (defined(%s) ? "'%s'" : "undef")
- if defined(%s);
-EOF
-}
+## Slot management
-sub _inline_check_coercion {
- my $self = shift;
- return '' unless $self->should_coerce;
- return 'my $val = $attr->type_constraint->coercion->coerce($_[1]);'
-}
+sub set_value {
+ my ($self, $instance, $value) = @_;
-sub _inline_check_required {
- my $self = shift;
- return '' unless $self->is_required;
- return 'defined($_[1]) || confess "Attribute ($attr_name) is required, so cannot be set to undef";'
-}
-
-sub _inline_check_lazy {
- my $self = shift;
- return '' unless $self->is_lazy;
- return '$_[0]->{$attr_name} = ($attr->has_default ? $attr->default($_[0]) : undef)'
- . 'unless exists $_[0]->{$attr_name};';
-}
+ my $attr_name = $self->name;
+ if ($self->is_required) {
+ defined($value)
+ || confess "Attribute ($attr_name) is required, so cannot be set to undef";
+ }
-sub _inline_store {
- my ($self, $instance, $value) = @_;
+ if ($self->has_type_constraint) {
- my $mi = $self->associated_class->get_meta_instance;
- my $slot_name = sprintf "'%s'", $self->slots;
+ my $type_constraint = $self->type_constraint;
- 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 $code;
-}
+ if ($self->should_coerce) {
+ $value = $type_constraint->coerce($value);
+ }
+ $type_constraint->_compiled_type_constraint->($value)
+ || confess "Attribute ($attr_name) does not pass the type constraint ("
+ . $type_constraint->name
+ . ") with "
+ . (defined($value)
+ ? ("'" . overload::StrVal($value) . "'")
+ : "undef")
+ if defined($value);
+ }
-sub _inline_trigger {
- my ($self, $instance, $value) = @_;
- return '' unless $self->has_trigger;
- return sprintf('$attr->trigger->(%s, %s, $attr);', $instance, $value);
-}
+ my $meta_instance = Class::MOP::Class->initialize(blessed($instance))
+ ->get_meta_instance;
-sub _inline_get {
- my ($self, $instance) = @_;
+ $meta_instance->set_slot_value($instance, $attr_name, $value);
- my $mi = $self->associated_class->get_meta_instance;
- my $slot_name = sprintf "'%s'", $self->slots;
+ if (ref $value && $self->is_weak_ref) {
+ $meta_instance->weaken_slot_value($instance, $attr_name);
+ }
- return $mi->inline_get_slot_value($instance, $slot_name);
+ if ($self->has_trigger) {
+ $self->trigger->($instance, $value, $self);
+ }
}
-sub _inline_auto_deref {
- my ( $self, $ref_value ) = @_;
+sub get_value {
+ my ($self, $instance) = @_;
- return $ref_value unless $self->should_auto_deref;
+ if ($self->is_lazy) {
+ unless ($self->has_value($instance)) {
+ if ($self->has_default) {
+ my $default = $self->default($instance);
+ $self->set_value($instance, $default);
+ }
+ if ( $self->has_builder ){
+ if (my $builder = $instance->can($self->builder)){
+ $self->set_value($instance, $instance->$builder);
+ }
+ else {
+ confess(blessed($instance)
+ . " does not support builder method '"
+ . $self->builder
+ . "' for attribute '"
+ . $self->name
+ . "'");
+ }
+ }
+ else {
+ $self->set_value($instance, undef);
+ }
+ }
+ }
- my $type = $self->type_constraint->name;
+ if ($self->should_auto_deref) {
- my $sigil;
- if ($type eq "ArrayRef") {
- $sigil = '@';
- }
- elsif ($type eq 'HashRef') {
- $sigil = '%';
- }
- else {
- confess "Can not auto de-reference the type constraint '$type'";
- }
+ my $type_constraint = $self->type_constraint;
- "(wantarray() ? $sigil\{ ( $ref_value ) || return } : ( $ref_value ) )";
-}
+ if ($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 '" . $type_constraint->name . "'";
+ }
-sub generate_accessor_method {
- my ($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->_inline_check_required
- . $attr->_inline_check_coercion
- . $attr->_inline_check_constraint($value_name)
- . $attr->_inline_store($inv, $value_name)
- . $attr->_inline_trigger($inv, $value_name)
- . ' }'
- . $attr->_inline_check_lazy
- . 'return ' . $attr->_inline_auto_deref($attr->_inline_get($inv))
- . ' }';
- my $sub = eval $code;
- confess "Could not create accessor for '$attr_name' because $@ \n code: $code" if $@;
- return $sub;
-}
+ }
+ else {
-sub generate_writer_method {
- my ($attr, $attr_name) = @_;
- my $value_name = $attr->should_coerce ? '$val' : '$_[1]';
- my $inv = '$_[0]';
- my $code = 'sub { '
- . $attr->_inline_check_required
- . $attr->_inline_check_coercion
- . $attr->_inline_check_constraint($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;
+ return $self->SUPER::get_value($instance);
+ }
}
-sub generate_reader_method {
- my $attr = shift;
- my $attr_name = $attr->slots;
- my $code = 'sub {'
- . 'confess "Cannot assign a value to a read-only accessor" if @_ > 1;'
- . $attr->_inline_check_lazy
- . 'return ' . $attr->_inline_auto_deref( '$_[0]->{$attr_name}' ) . ';'
- . '}';
- my $sub = eval $code;
- confess "Could not create reader for '$attr_name' because $@ \n code: $code" if $@;
- return $sub;
-}
+## installing accessors
+
+sub accessor_metaclass { 'Moose::Meta::Method::Accessor' }
sub install_accessors {
my $self = shift;
- $self->SUPER::install_accessors(@_);
-
+ $self->SUPER::install_accessors(@_);
+
if ($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
+ # 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';
-
+
+ # find the accessor method for this attribute
+ my $accessor = $self->get_read_method_ref;
+ # then unpack it if we need too ...
+ $accessor = $accessor->body if blessed $accessor;
+
# install the delegation ...
my $associated_class = $self->associated_class;
foreach my $handle (keys %handles) {
my $method_to_call = $handles{$handle};
-
+ my $class_name = $associated_class->name;
+ my $name = "${class_name}::${handle}";
+
(!$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.
+
+ # FIXME warn when $handle was explicitly specified, but not if the source is a regex or something
+ #cluck("Not delegating method '$handle' because it is a core method") and
+ next if $class_name->isa("Moose::Object") and $handle =~ /^BUILD|DEMOLISH$/ || Moose::Object->can($handle);
+
if ((reftype($method_to_call) || '') eq 'CODE') {
- $associated_class->add_method($handle => $method_to_call);
+ $associated_class->add_method($handle => subname $name, $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(@_);
+ $associated_class->add_method($handle => subname $name, sub {
+ my $proxy = (shift)->$accessor();
+ @_ = ($proxy, @_);
+ (defined $proxy)
+ || confess "Cannot delegate $handle to $method_to_call because " .
+ "the value of " . $self->name . " is not defined";
+ goto &{ $proxy->can($method_to_call) || return };
});
}
}
}
-
+
return;
}
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);
+ if (my $handle_type = ref($handles)) {
+ if ($handle_type eq 'HASH') {
+ return %{$handles};
+ }
+ elsif ($handle_type eq 'ARRAY') {
+ return map { $_ => $_ } @{$handles};
+ }
+ elsif ($handle_type eq 'Regexp') {
+ ($self->has_type_constraint)
+ || confess "Cannot delegate methods based on a RegExpr without a type constraint (isa)";
+ return map { ($_ => $_) }
+ grep { /$handles/ } $self->_get_delegate_method_list;
+ }
+ elsif ($handle_type eq 'CODE') {
+ return $handles->($self, $self->_find_delegate_metaclass);
+ }
+ else {
+ confess "Unable to canonicalize the 'handles' option with $handles";
+ }
}
else {
- confess "Unable to canonicalize the 'handles' option with $handles";
+ my $role_meta = eval { $handles->meta };
+ if ($@) {
+ confess "Unable to canonicalize the 'handles' option with $handles because : $@";
+ }
+
+ (blessed $role_meta && $role_meta->isa('Moose::Meta::Role'))
+ || confess "Unable to canonicalize the 'handles' option with $handles because ->meta is not a Moose::Meta::Role";
+
+ return map { $_ => $_ } (
+ $role_meta->get_method_list,
+ $role_meta->get_required_method_list
+ );
}
}
sub _find_delegate_metaclass {
my $self = shift;
if (my $class = $self->_isa_metadata) {
- # if the class does have
+ # if the class does have
# a meta method, use it
return $class->meta if $class->can('meta');
- # otherwise we might be
+ # otherwise we might be
# dealing with a non-Moose
- # class, and need to make
+ # class, and need to make
# our own metaclass
return Moose::Meta::Class->initialize($class);
}
elsif (my $role = $self->_does_metadata) {
- # our role will always have
+ # our role will always have
# a meta method
return $role->meta;
}
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' }
+ grep { $_->{class} ne 'Moose::Object' && $_->{name} ne 'meta' }
$meta->compute_all_applicable_methods;
}
elsif ($meta->isa('Moose::Meta::Role')) {
- return $meta->get_method_list;
+ return $meta->get_method_list;
}
else {
confess "Unable to recognize the delegate metaclass '$meta'";
=head1 DESCRIPTION
-This is a subclass of L<Class::MOP::Attribute> with Moose specific
-extensions.
+This is a subclass of L<Class::MOP::Attribute> with Moose specific
+extensions.
-For the most part, the only time you will ever encounter an
-instance of this class is if you are doing some serious deep
-introspection. To really understand this class, you need to refer
+For the most part, the only time you will ever encounter an
+instance of this class is if you are doing some serious deep
+introspection. To really understand this class, you need to refer
to the L<Class::MOP::Attribute> documentation.
=head1 METHODS
=head2 Overridden methods
-These methods override methods in L<Class::MOP::Attribute> and add
-Moose specific features. You can safely assume though that they
+These methods override methods in L<Class::MOP::Attribute> and add
+Moose specific features. You can safely assume though that they
will behave just as L<Class::MOP::Attribute> does.
=over 4
=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<install_accessors>
+=item B<set_value>
+
+ eval { $point->meta->get_attribute('x')->set_value($point, 'fourty-two') };
+ if($@) {
+ print "Oops: $@\n";
+ }
+
+I<Attribute (x) does not pass the type constraint (Int) with 'fourty-two'>
+
+Before setting the value, a check is made on the type constraint of
+the attribute, if it has one, to see if the value passes it. If the
+value fails to pass, the set operation dies with a L<Carp/confess>.
+
+Any coercion to convert values is done before checking the type constraint.
+
+To check a value against a type constraint before setting it, fetch the
+attribute instance using L<Class::MOP::Class/find_attribute_by_name>,
+fetch the type_constraint from the attribute using L<Moose::Meta::Attribute/type_constraint>
+and call L<Moose::Meta::TypeConstraint/check>. See L<Moose::Cookbook::RecipeX>
+for an example.
=back
=head2 Additional Moose features
-Moose attributes support type-constraint checking, weak reference
-creation and type coercion.
+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
+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>
=item B<type_constraint>
-A read-only accessor for this meta-attribute's type constraint. For
-more information on what you can do with this, see the documentation
+A read-only accessor for this meta-attribute's type constraint. For
+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 should be initialized lazily.
-NOTE: lazy attributes, B<must> have a C<default> field set.
+NOTE: lazy attributes, B<must> have a C<default> or C<builder> field set.
+
+=item B<is_lazy_build>
+
+Returns true if this meta-attribute should be initialized lazily through
+the builder generated by lazy_build. Using C<lazy_build =E<gt> 1> will
+make your attribute required and lazy. In addition it will set the builder, clearer
+and predicate options for you using the following convention.
+
+ #If your attribute name starts with an underscore:
+ has '_foo' => (lazy_build => 1);
+ #is the same as
+ has '_foo' => (lazy => 1, required => 1, predicate => '_has_foo', clearer => '_clear_foo', builder => '_build__foo);
+ # or
+ has '_foo' => (lazy => 1, required => 1, predicate => '_has_foo', clearer => '_clear_foo', default => sub{shift->_build__foo});
+
+ #If your attribute name does not start with an underscore:
+ has 'foo' => (lazy_build => 1);
+ #is the same as
+ has 'foo' => (lazy => 1, required => 1, predicate => 'has_foo', clearer => 'clear_foo', builder => '_build_foo);
+ # or
+ has 'foo' => (lazy => 1, required => 1, predicate => 'has_foo', clearer => 'clear_foo', default => sub{shift->_build_foo});
+
+The reason for the different naming of the C<builder> is that the C<builder>
+method is a private method while the C<clearer> and C<predicate> methods
+are public methods.
+
+NOTE: This means your class should provide a method whose name matches the value
+of the builder part, in this case _build__foo or _build_foo.
=item B<should_coerce>
=item B<should_auto_deref>
-Returns true if this meta-attribute should perform automatic
-auto-dereferencing.
+Returns true if this meta-attribute should perform automatic
+auto-dereferencing.
-NOTE: This can only be done for attributes whose type constraint is
+NOTE: This can only be done for attributes whose type constraint is
either I<ArrayRef> or I<HashRef>.
=item B<has_trigger>
=item B<trigger>
-This is a CODE reference which will be executed every time the
-value of an attribute is assigned. The CODE ref will get two values,
-the invocant and the new value. This can be used to handle I<basic>
+This is a CODE reference which will be executed every time the
+value of an attribute is assigned. The CODE ref will get two values,
+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
-All complex software has bugs lurking in it, and this module is no
+All complex software has bugs lurking in it, and this module is no
exception. If you find a bug please either email me, or add the bug
to cpan-RT.
=head1 COPYRIGHT AND LICENSE
-Copyright 2006 by Infinity Interactive, Inc.
+Copyright 2006-2008 by Infinity Interactive, Inc.
L<http://www.iinteractive.com>
This library is free software; you can redistribute it and/or modify
-it under the same terms as Perl itself.
+it under the same terms as Perl itself.
=cut
projects / gitmo/Moose.git / blobdiff