package Moose::Util;
use strict;
use warnings;
use Sub::Exporter;
use Scalar::Util 'blessed';
use Carp 'confess';
use Class::MOP 0.56;
our $VERSION = '0.54';
our $AUTHORITY = 'cpan:STEVAN';
my @exports = qw[
find_meta
does_role
search_class_by_role
apply_all_roles
get_all_init_args
get_all_attribute_values
resolve_metatrait_alias
resolve_metaclass_alias
add_method_modifier
];
Sub::Exporter::setup_exporter({
exports => \@exports,
groups => { all => \@exports }
});
## some utils for the utils ...
sub find_meta {
return unless $_[0];
return Class::MOP::get_metaclass_by_name(blessed($_[0]) || $_[0]);
}
## the functions ...
sub does_role {
my ($class_or_obj, $role) = @_;
my $meta = find_meta($class_or_obj);
return unless defined $meta;
return unless $meta->can('does_role');
return 1 if $meta->does_role($role);
return;
}
sub search_class_by_role {
my ($class_or_obj, $role_name) = @_;
my $meta = find_meta($class_or_obj);
return unless defined $meta;
foreach my $class ($meta->class_precedence_list) {
my $_meta = find_meta($class);
next unless defined $_meta;
foreach my $role (@{ $_meta->roles || [] }) {
return $class if $role->name eq $role_name;
}
}
return;
}
sub apply_all_roles {
my $applicant = shift;
confess "Must specify at least one role to apply to $applicant" unless @_;
my $roles = Data::OptList::mkopt([ @_ ]);
#use Data::Dumper;
#warn Dumper $roles;
my $meta = (blessed $applicant ? $applicant : find_meta($applicant));
foreach my $role_spec (@$roles) {
Class::MOP::load_class($role_spec->[0]);
}
($_->[0]->can('meta') && $_->[0]->meta->isa('Moose::Meta::Role'))
|| confess "You can only consume roles, " . $_->[0] . " is not a Moose role"
foreach @$roles;
if (scalar @$roles == 1) {
my ($role, $params) = @{$roles->[0]};
$role->meta->apply($meta, (defined $params ? %$params : ()));
}
else {
Moose::Meta::Role->combine(
@$roles
)->apply($meta);
}
}
# instance deconstruction ...
sub get_all_attribute_values {
my ($class, $instance) = @_;
return +{
map { $_->name => $_->get_value($instance) }
grep { $_->has_value($instance) }
$class->compute_all_applicable_attributes
};
}
sub get_all_init_args {
my ($class, $instance) = @_;
return +{
map { $_->init_arg => $_->get_value($instance) }
grep { $_->has_value($instance) }
grep { defined($_->init_arg) }
$class->compute_all_applicable_attributes
};
}
sub resolve_metatrait_alias {
resolve_metaclass_alias( @_, trait => 1 );
}
sub resolve_metaclass_alias {
my ( $type, $metaclass_name, %options ) = @_;
if ( my $resolved = eval {
my $possible_full_name = 'Moose::Meta::' . $type . '::Custom::' . ( $options{trait} ? "Trait::" : "" ) . $metaclass_name;
Class::MOP::load_class($possible_full_name);
$possible_full_name->can('register_implementation')
? $possible_full_name->register_implementation
: $possible_full_name;
} ) {
return $resolved;
} else {
Class::MOP::load_class($metaclass_name);
return $metaclass_name;
}
}
sub add_method_modifier {
my ( $class_or_obj, $modifier_name, $args ) = @_;
my $meta = find_meta($class_or_obj);
my $code = pop @{$args};
my $add_modifier_method = 'add_' . $modifier_name . '_method_modifier';
if ( my $method_modifier_type = ref( @{$args}[0] ) ) {
if ( $method_modifier_type eq 'Regexp' ) {
my @all_methods = $meta->compute_all_applicable_methods;
my @matched_methods
= grep { $_->{name} =~ @{$args}[0] } @all_methods;
$meta->$add_modifier_method( $_->{name}, $code )
for @matched_methods;
}
}
else {
$meta->$add_modifier_method( $_, $code ) for @{$args};
}
}
1;
__END__
=pod
=head1 NAME
Moose::Util - Utilities for working with Moose classes
=head1 SYNOPSIS
use Moose::Util qw/find_meta does_role search_class_by_role/;
my $meta = find_meta($object) || die "No metaclass found";
if (does_role($object, $role)) {
print "The object can do $role!\n";
}
my $class = search_class_by_role($object, 'FooRole');
print "Nearest class with 'FooRole' is $class\n";
=head1 DESCRIPTION
This is a set of utility functions to help working with Moose classes, and
is used internally by Moose itself. The goal is to provide useful functions
that for both Moose users and Moose extenders (MooseX:: authors).
This is a relatively new addition to the Moose toolchest, so ideas,
suggestions and contributions to this collection are most welcome.
See the L<TODO> section below for a list of ideas for possible functions
to write.
=head1 EXPORTED FUNCTIONS
=over 4
=item B<find_meta ($class_or_obj)>
This will attempt to locate a metaclass for the given C<$class_or_obj>
and return it.
=item B<does_role ($class_or_obj, $role_name)>
Returns true if C<$class_or_obj> can do the role C<$role_name>.
=item B<search_class_by_role ($class_or_obj, $role_name)>
Returns first class in precedence list that consumed C<$role_name>.
=item B<apply_all_roles ($applicant, @roles)>
Given an C<$applicant> (which can somehow be turned into either a
metaclass or a metarole) and a list of C<@roles> this will do the
right thing to apply the C<@roles> to the C<$applicant>. This is
actually used internally by both L<Moose> and L<Moose::Role>, and the
C<@roles> will be pre-processed through L<Data::OptList::mkopt>
to allow for the additional arguments to be passed.
=item B<get_all_attribute_values($meta, $instance)>
Returns the values of the C<$instance>'s fields keyed by the attribute names.
=item B<get_all_init_args($meta, $instance)>
Returns a hash reference where the keys are all the attributes' C<init_arg>s
and the values are the instance's fields. Attributes without an C<init_arg>
will be skipped.
=item B<resolve_metaclass_alias($category, $name, %options)>
=item B<resolve_metatrait_alias($category, $name, %options)>
Resolve a short name like in e.g.
has foo => (
metaclass => "Bar",
);
to a full class name.
=item B<add_method_modifier ($class_or_obj, $modifier_name, $args)>
=back
=head1 TODO
Here is a list of possible functions to write
=over 4
=item discovering original method from modified method
=item search for origin class of a method or attribute
=back
=head1 BUGS
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 AUTHOR
Anders Nor Berle E<lt>debolaz@gmail.comE<gt>
B<with contributions from:>
Robert (phaylon) Sedlacek
Stevan Little
=head1 COPYRIGHT AND LICENSE
Copyright 2007-2008 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.
=cut