package Class::MOP::Mixin::AttributeCore;
our $VERSION = '2.4000';

use strict;
use warnings;

use Scalar::Util 'blessed';

use parent 'Class::MOP::Mixin';

sub has_accessor        { defined $_[0]->{'accessor'} }
sub has_reader          { defined $_[0]->{'reader'} }
sub has_writer          { defined $_[0]->{'writer'} }
sub has_predicate       { defined $_[0]->{'predicate'} }
sub has_clearer         { defined $_[0]->{'clearer'} }
sub has_builder         { defined $_[0]->{'builder'} }
sub has_init_arg        { defined $_[0]->{'init_arg'} }
sub has_default         { exists  $_[0]->{'default'} }
sub has_initializer     { defined $_[0]->{'initializer'} }
sub has_insertion_order { defined $_[0]->{'insertion_order'} }

sub _set_insertion_order { $_[0]->{'insertion_order'} = $_[1] }

sub has_read_method  { $_[0]->has_reader || $_[0]->has_accessor }
sub has_write_method { $_[0]->has_writer || $_[0]->has_accessor }

sub is_default_a_coderef {
    # Uber hack because it is called from CMOP::Attribute constructor as
    # $class->is_default_a_coderef(\%options)
    my ($value) = ref $_[0] ? $_[0]->{'default'} : $_[1]->{'default'};

    return unless ref($value);

    return ref($value) eq 'CODE'
        || ( blessed($value) && $value->isa('Class::MOP::Method') );
}

sub default {
    my ( $self, $instance ) = @_;
    if ( defined $instance && $self->is_default_a_coderef ) {
        # if the default is a CODE ref, then we pass in the instance and
        # default can return a value based on that instance. Somewhat crude,
        # but works.
        return $self->{'default'}->($instance);
    }
    $self->{'default'};
}

1;

# ABSTRACT: Core attributes shared by attribute metaclasses

__END__

=pod

=encoding UTF-8

=head1 NAME

Class::MOP::Mixin::AttributeCore - Core attributes shared by attribute metaclasses

=head1 VERSION

version 2.4000

=head1 DESCRIPTION

This class implements the core attributes (aka properties) shared by all
attributes. See the L<Class::MOP::Attribute> documentation for API details.

=head1 AUTHORS

=over 4

=item *

Stevan Little <stevan@cpan.org>

=item *

Dave Rolsky <autarch@urth.org>

=item *

Jesse Luehrs <doy@cpan.org>

=item *

Shawn M Moore <sartak@cpan.org>

=item *

יובל קוג'מן (Yuval Kogman) <nothingmuch@woobling.org>

=item *

Karen Etheridge <ether@cpan.org>

=item *

Florian Ragwitz <rafl@debian.org>

=item *

Hans Dieter Pearcey <hdp@cpan.org>

=item *

Chris Prather <chris@prather.org>

=item *

Matt S Trout <mstrout@cpan.org>

=back

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2006 by Infinity Interactive, Inc.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.

=cut
