package MooseX::AttributeHelpers::Base;
use Moose;
+use Moose::Util::TypeConstraints;
our $VERSION = '0.01';
our $AUTHORITY = 'cpan:STEVAN';
extends 'Moose::Meta::Attribute';
-has 'method_constructors' => (
- is => 'ro',
- isa => 'HashRef',
- default => sub { {} }
-);
-
+# this is the method map you define ...
has 'provides' => (
is => 'ro',
isa => 'HashRef',
required => 1,
);
+
+# these next two are the possible methods
+# you can use in the 'provides' map.
+
+# provide a Class or Role which we can
+# collect the method providers from
+has 'method_provider' => (
+ is => 'ro',
+ isa => 'ClassName',
+ predicate => 'has_method_provider',
+);
+
+# or you can provide a HASH ref of anon subs
+# yourself. This will also collect and store
+# the methods from a method_provider as well
+has 'method_constructors' => (
+ is => 'ro',
+ isa => 'HashRef',
+ lazy => 1,
+ default => sub {
+ my $self = shift;
+ return +{} unless $self->has_method_provider;
+ # or grab them from the role/class
+ my $method_provider = $self->method_provider->meta;
+ return +{
+ map {
+ $_ => $method_provider->get_method($_)
+ } $method_provider->get_method_list
+ };
+ }
+);
+
# extend the parents stuff to make sure
# certain bits are now required ...
has '+$!default' => (required => 1);
has '+type_constraint' => (required => 1);
-# this confirms that provides has
-# all valid possibilities in it
-sub _check_provides {
- my ($self, $provides) = @_;
- my $method_constructors = $self->method_constructors;
- foreach my $key (keys %$provides) {
- (exists $method_constructors->{$key})
- || confess "$key is an unsupported method type";
- }
-}
+## Methods called prior to instantiation
+
+sub helper_type { () }
-# this provides an opportunity to
-# manipulate the %options to handle
-# some of the provides features
-# correctly.
-sub _process_options_for_provides {
+sub process_options_for_provides {
my ($self, $options) = @_;
- # ...
+
+ if (my $type = $self->helper_type) {
+ (exists $options->{isa})
+ || confess "You must define a type with the $type metaclass";
+
+ my $isa = $options->{isa};
+
+ unless (blessed($isa) && $isa->isa('Moose::Meta::TypeConstraint')) {
+ $isa = find_type_constraint($isa);
+ }
+
+ ($isa->is_a_type_of($type))
+ || confess "The type constraint for a $type ($options->{isa}) must be a subtype of $type";
+ }
}
before '_process_options' => sub {
- my ($self, %options) = @_;
- if (exists $options{provides}) {
- $self->_check_provides($options{provides});
- $self->_process_options_for_provides(\%options);
+ my ($self, $name, $options) = @_;
+ if (exists $options->{provides}) {
+ $self->process_options_for_provides($options);
}
};
+## methods called after instantiation
+
+# this confirms that provides has
+# all valid possibilities in it
+sub check_provides_values {
+ my $self = shift;
+
+ my $method_constructors = $self->method_constructors;
+
+ foreach my $key (keys %{$self->provides}) {
+ (exists $method_constructors->{$key})
+ || confess "$key is an unsupported method type";
+ }
+}
+
after 'install_accessors' => sub {
my $attr = shift;
my $class = $attr->associated_class;
+ # before we install them, lets
+ # make sure they are valid
+ $attr->check_provides_values;
+
my $method_constructors = $attr->method_constructors;
foreach my $key (keys %{$attr->provides}) {
- $class->add_method(
- $attr->provides->{$key},
- $method_constructors->{$key}->($attr)
+
+ my $method_name = $attr->provides->{$key};
+ my $method_body = $method_constructors->{$key}->($attr);
+
+ if ($class->has_method($method_name)) {
+ confess "The method ($method_name) already exists in class (" . $class->name . ")";
+ }
+
+ $class->add_method($method_name =>
+ MooseX::AttributeHelpers::Meta::Method::Provided->wrap(
+ $method_body,
+ )
);
}
};
no Moose;
+no Moose::Util::TypeConstraints;
1;
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
-=cut
\ No newline at end of file
+=cut