-#!/usr/bin/env perl
package Mouse::Meta::Attribute;
use strict;
use warnings;
-use Carp 'confess';
-use Scalar::Util 'blessed';
+use Mouse::Util;
-sub new {
- my $class = shift;
- my %args = @_;
-
- $args{init_arg} = $args{name}
- unless exists $args{init_arg};
- $args{is} ||= '';
-
- bless \%args, $class;
-}
+use Mouse::Meta::TypeConstraint;
+use Mouse::Meta::Method::Accessor;
-sub name { $_[0]->{name} }
-sub class { $_[0]->{class} }
-sub _is_metadata { $_[0]->{is} }
-sub is_required { $_[0]->{required} }
-sub default { $_[0]->{default} }
-sub is_lazy { $_[0]->{lazy} }
-sub predicate { $_[0]->{predicate} }
-sub clearer { $_[0]->{clearer} }
-sub handles { $_[0]->{handles} }
-sub is_weak_ref { $_[0]->{weak_ref} }
-sub init_arg { $_[0]->{init_arg} }
-sub type_constraint { $_[0]->{type_constraint} }
-sub trigger { $_[0]->{trigger} }
-sub builder { $_[0]->{builder} }
-sub should_auto_deref { $_[0]->{auto_deref} }
-
-sub has_default { exists $_[0]->{default} }
-sub has_predicate { exists $_[0]->{predicate} }
-sub has_clearer { exists $_[0]->{clearer} }
-sub has_handles { exists $_[0]->{handles} }
-sub has_type_constraint { exists $_[0]->{type_constraint} }
-sub has_trigger { exists $_[0]->{trigger} }
-sub has_builder { exists $_[0]->{builder} }
-
-sub generate_accessor {
- my $attribute = shift;
-
- my $name = $attribute->name;
- my $key = $name;
- my $default = $attribute->default;
- my $trigger = $attribute->trigger;
- my $type = $attribute->type_constraint;
- my $constraint = $attribute->find_type_constraint;
- my $builder = $attribute->builder;
-
- my $accessor = 'sub {
- my $self = shift;';
-
- if ($attribute->_is_metadata eq 'rw') {
- $accessor .= 'if (@_) {
- local $_ = $_[0];';
-
- if ($constraint) {
- $accessor .= 'do {
- my $display = defined($_) ? overload::StrVal($_) : "undef";
- Carp::confess("Attribute ($name) does not pass the type constraint because: Validation failed for \'$type\' failed with value $display") unless $constraint->();
- };'
- }
+sub new {
+ my ($class, $name, %options) = @_;
- $accessor .= '$self->{$key} = $_;';
+ $options{name} = $name;
- if ($attribute->is_weak_ref) {
- $accessor .= 'Scalar::Util::weaken($self->{$key}) if ref($self->{$key});';
- }
+ $options{init_arg} = $name
+ unless exists $options{init_arg};
- if ($trigger) {
- $accessor .= '$trigger->($self, $_, $attribute);';
- }
+ my $is = $options{is} ||= '';
- $accessor .= '}';
+ if($is eq 'rw'){
+ $options{accessor} = $name if !exists $options{accessor};
}
- else {
- $accessor .= 'confess "Cannot assign a value to a read-only accessor" if @_;';
+ elsif($is eq 'ro'){
+ $options{reader} = $name if !exists $options{reader};
}
- if ($attribute->is_lazy) {
- $accessor .= '$self->{$key} = ';
-
- $accessor .= $attribute->has_builder
- ? '$self->$builder'
- : ref($default) eq 'CODE'
- ? '$default->($self)'
- : '$default';
-
- $accessor .= ' if !exists($self->{$key});';
- }
+ bless \%options, $class;
+}
- if ($attribute->should_auto_deref) {
- if ($attribute->type_constraint eq 'ArrayRef') {
- $accessor .= 'if (wantarray) {
- return @{ $self->{$key} || [] };
- }';
- }
- else {
- $accessor .= 'if (wantarray) {
- return %{ $self->{$key} || {} };
- }';
- }
- }
+# readers
+
+sub name { $_[0]->{name} }
+sub associated_class { $_[0]->{associated_class} }
+
+sub accessor { $_[0]->{accessor} }
+sub reader { $_[0]->{reader} }
+sub writer { $_[0]->{writer} }
+sub predicate { $_[0]->{predicate} }
+sub clearer { $_[0]->{clearer} }
+sub handles { $_[0]->{handles} }
+
+sub _is_metadata { $_[0]->{is} }
+sub is_required { $_[0]->{required} }
+sub default { $_[0]->{default} }
+sub is_lazy { $_[0]->{lazy} }
+sub is_lazy_build { $_[0]->{lazy_build} }
+sub is_weak_ref { $_[0]->{weak_ref} }
+sub init_arg { $_[0]->{init_arg} }
+sub type_constraint { $_[0]->{type_constraint} }
+sub find_type_constraint {
+ Carp::carp("This method was deprecated");
+ $_[0]->type_constraint();
+}
+sub trigger { $_[0]->{trigger} }
+sub builder { $_[0]->{builder} }
+sub should_auto_deref { $_[0]->{auto_deref} }
+sub should_coerce { $_[0]->{should_coerce} }
+
+# predicates
+
+sub has_accessor { exists $_[0]->{accessor} }
+sub has_reader { exists $_[0]->{reader} }
+sub has_writer { exists $_[0]->{writer} }
+sub has_predicate { exists $_[0]->{predicate} }
+sub has_clearer { exists $_[0]->{clearer} }
+sub has_handles { exists $_[0]->{handles} }
+
+sub has_default { exists $_[0]->{default} }
+sub has_type_constraint { exists $_[0]->{type_constraint} }
+sub has_trigger { exists $_[0]->{trigger} }
+sub has_builder { exists $_[0]->{builder} }
+
+sub _create_args {
+ $_[0]->{_create_args} = $_[1] if @_ > 1;
+ $_[0]->{_create_args}
+}
- $accessor .= 'return $self->{$key};
- }';
+sub accessor_metaclass { 'Mouse::Meta::Method::Accessor' }
- return eval $accessor;
-}
+sub create {
+ my ($self, $class, $name, %args) = @_;
-sub generate_predicate {
- my $attribute = shift;
- my $key = $attribute->name;
+ $args{name} = $name;
+ $args{associated_class} = $class;
- my $predicate = 'sub { exists($_[0]->{$key}) }';
+ %args = $self->canonicalize_args($name, %args);
+ $self->validate_args($name, \%args);
- return eval $predicate;
-}
+ $args{should_coerce} = delete $args{coerce}
+ if exists $args{coerce};
-sub generate_clearer {
- my $attribute = shift;
- my $key = $attribute->name;
+ if (exists $args{isa}) {
+ my $type_constraint = delete $args{isa};
+ $args{type_constraint}= Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($type_constraint);
+ }
- my $predicate = 'sub { delete($_[0]->{$key}) }';
+ my $attribute = $self->new($name, %args);
- return eval $predicate;
-}
+ $attribute->_create_args(\%args);
-sub generate_handles {
- my $attribute = shift;
- my $reader = $attribute->name;
- my %handles = $attribute->_canonicalize_handles($attribute->handles);
+ $class->add_attribute($attribute);
- my %method_map;
+ my $associated_methods = 0;
- for my $local_method (keys %handles) {
- my $remote_method = $handles{$local_method};
+ my $generator_class = $self->accessor_metaclass;
+ foreach my $type(qw(accessor reader writer predicate clearer handles)){
+ if(exists $attribute->{$type}){
+ my $installer = '_install_' . $type;
+ $generator_class->$installer($attribute, $attribute->{$type}, $class);
+ $associated_methods++;
+ }
+ }
- my $method = 'sub {
- my $self = shift;
- $self->$reader->$remote_method(@_)
- }';
+ if($associated_methods == 0 && ($attribute->_is_metadata || '') ne 'bare'){
+ Carp::cluck(qq{Attribute ($name) of class }.$class->name.qq{ has no associated methods (did you mean to provide an "is" argument?)});
- $method_map{$local_method} = eval $method;
}
- return \%method_map;
+ return $attribute;
}
-sub create {
- my ($self, $class, $name, %args) = @_;
-
- confess "You cannot have lazy attribute ($name) without specifying a default value for it"
- if $args{lazy} && !exists($args{default}) && !exists($args{builder});
+sub canonicalize_args {
+ my $self = shift;
+ my $name = shift;
+ my %args = @_;
+
+ if ($args{lazy_build}) {
+ $args{lazy} = 1;
+ $args{required} = 1;
+ $args{builder} = "_build_${name}"
+ if !exists($args{builder});
+ if ($name =~ /^_/) {
+ $args{clearer} = "_clear${name}" if !exists($args{clearer});
+ $args{predicate} = "_has${name}" if !exists($args{predicate});
+ }
+ else {
+ $args{clearer} = "clear_${name}" if !exists($args{clearer});
+ $args{predicate} = "has_${name}" if !exists($args{predicate});
+ }
+ }
- confess "References are not allowed as default values, you must wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])"
- if ref($args{default})
- && ref($args{default}) ne 'CODE';
+ return %args;
+}
- confess "You cannot auto-dereference without specifying a type constraint on attribute $name"
- if $args{auto_deref} && !exists($args{isa});
+sub validate_args {
+ my $self = shift;
+ my $name = shift;
+ my $args = shift;
- confess "You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute $name"
- if $args{auto_deref}
- && $args{isa} ne 'ArrayRef'
- && $args{isa} ne 'HashRef';
+ $self->throw_error("You can not use lazy_build and default for the same attribute ($name)")
+ if $args->{lazy_build} && exists $args->{default};
- $args{type_constraint} = delete $args{isa}
- if exists $args{isa};
+ $self->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it")
+ if $args->{lazy}
+ && !exists($args->{default})
+ && !exists($args->{builder});
- my $attribute = $self->new(%args, name => $name, class => $class);
- my $meta = $class->meta;
+ $self->throw_error("References are not allowed as default values, you must wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])")
+ if ref($args->{default})
+ && ref($args->{default}) ne 'CODE';
- $meta->add_attribute($attribute);
+ $self->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)")
+ if $args->{auto_deref} && !exists($args->{isa});
- # install an accessor
- if ($attribute->_is_metadata eq 'rw' || $attribute->_is_metadata eq 'ro') {
- my $accessor = $attribute->generate_accessor;
- no strict 'refs';
- *{ $class . '::' . $name } = $accessor;
- }
+ $self->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)")
+ if $args->{auto_deref}
+ && $args->{isa} !~ /^(?:ArrayRef|HashRef)(?:\[.*\])?$/;
- for my $method (qw/predicate clearer/) {
- my $predicate = "has_$method";
- if ($attribute->$predicate) {
- my $generator = "generate_$method";
- my $coderef = $attribute->$generator;
- no strict 'refs';
- *{ $class . '::' . $attribute->$method } = $coderef;
+ if ($args->{trigger}) {
+ if (ref($args->{trigger}) eq 'HASH') {
+ $self->throw_error("HASH-based form of trigger has been removed. Only the coderef form of triggers are now supported.");
}
- }
- if ($attribute->has_handles) {
- my $method_map = $attribute->generate_handles;
- for my $method_name (keys %$method_map) {
- no strict 'refs';
- *{ $class . '::' . $method_name } = $method_map->{$method_name};
- }
+ $self->throw_error("Trigger must be a CODE ref on attribute ($name)")
+ if ref($args->{trigger}) ne 'CODE';
}
- return $attribute;
+ return 1;
}
-sub find_type_constraint {
- my $self = shift;
- my $type = $self->type_constraint;
-
- return unless $type;
+sub verify_against_type_constraint {
+ my ($self, $value) = @_;
+ my $tc = $self->type_constraint;
+ return 1 unless $tc;
- my $checker = Mouse::TypeRegistry->optimized_constraints->{$type};
- return $checker if $checker;
+ local $_ = $value;
+ return 1 if $tc->check($value);
- return sub { blessed($_) && blessed($_) eq $type };
+ $self->verify_type_constraint_error($self->name, $value, $tc);
}
-sub verify_type_constraint {
- my $self = shift;
- local $_ = shift;
-
- my $type = $self->type_constraint
- or return 1;
- my $constraint = $self->find_type_constraint;
-
- return 1 if $constraint->($_);
+sub verify_type_constraint_error {
+ my($self, $name, $value, $type) = @_;
+ $self->throw_error("Attribute ($name) does not pass the type constraint because: " . $type->get_message($value));
+}
- my $name = $self->name;
- my $display = defined($_) ? overload::StrVal($_) : 'undef';
- Carp::confess("Attribute ($name) does not pass the type constraint because: Validation failed for \'$type\' failed with value $display");
+sub coerce_constraint { ## my($self, $value) = @_;
+ my $type = $_[0]->{type_constraint}
+ or return $_[1];
+ return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $_[0]->type_constraint, $_[1]);
}
sub _canonicalize_handles {
return map { $_ => $_ } @$handles;
}
else {
- confess "Unable to canonicalize the 'handles' option with $handles";
+ $self->throw_error("Unable to canonicalize the 'handles' option with $handles");
+ }
+}
+
+sub clone_parent {
+ my $self = shift;
+ my $class = shift;
+ my $name = shift;
+ my %args = ($self->get_parent_args($class, $name), @_);
+
+ $self->create($class, $name, %args);
+}
+
+sub get_parent_args {
+ my $self = shift;
+ my $class = shift;
+ my $name = shift;
+
+ for my $super ($class->linearized_isa) {
+ my $super_attr = $super->can("meta") && $super->meta->get_attribute($name)
+ or next;
+ return %{ $super_attr->_create_args };
}
+
+ $self->throw_error("Could not find an attribute by the name of '$name' to inherit from");
+}
+
+sub throw_error{
+ my $self = shift;
+
+ my $metaclass = (ref $self && $self->associated_class) || 'Mouse::Meta::Class';
+ $metaclass->throw_error(@_, depth => 1);
}
1;
=head2 name -> AttributeName
-=head2 class -> OwnerClass
+=head2 associated_class -> OwnerClass
=head2 is_required -> Bool
=head2 has_builder -> Bool
+=head2 is_lazy_build => Bool
+
=head2 should_auto_deref -> Bool
Informational methods.
-=head2 generate_accessor -> CODE
-
-Creates a new code reference for the attribute's accessor.
-
-=head2 generate_predicate -> CODE
+=head2 verify_against_type_constraint Item -> 1 | ERROR
-Creates a new code reference for the attribute's predicate.
+Checks that the given value passes this attribute's type constraint. Returns 1
+on success, otherwise C<confess>es.
-=head2 generate_clearer -> CODE
+=head2 canonicalize_args Name, %args -> %args
-Creates a new code reference for the attribute's clearer.
+Canonicalizes some arguments to create. In particular, C<lazy_build> is
+canonicalized into C<lazy>, C<builder>, etc.
-=head2 generate_handles -> { MethodName => CODE }
+=head2 validate_args Name, \%args -> 1 | ERROR
-Creates a new code reference for each of the attribute's handles methods.
+Checks that the arguments to create the attribute (ie those specified by
+C<has>) are valid.
-=head2 find_type_constraint -> CODE
+=head2 clone_parent OwnerClass, AttributeName, %args -> Mouse::Meta::Attribute
-Returns a code reference which can be used to check that a given value passes
-this attribute's type constraint;
+Creates a new attribute in OwnerClass, inheriting options from parent classes.
+Accessors and helper methods are installed. Some error checking is done.
-=head2 verify_type_constraint Item -> 1 | ERROR
+=head2 get_parent_args OwnerClass, AttributeName -> Hash
-Checks that the given value passes this attribute's type constraint. Returns 1
-on success, otherwise C<confess>es.
+Returns the options that the parent class of C<OwnerClass> used for attribute
+C<AttributeName>.
=cut
projects / gitmo/Mouse.git / blobdiff