On Fri, Apr 24, 2009 at 05:02:35PM +0100, Mark Morgan wrote:
> A very limited functionality, which won't be extended any further. It
> seems to me the ideal candidate for handling as parameterized roles,
> as described earlier in the thread, in order to get common behaviour
> out of an oft-repeated idiom.
Getting "common behavior out of an oft-repeated idiom" is just refactoring,
generically, not something specific to parameterized roles.
The fact that you won't extend it any further makes me think that a simple
wrapper around has() is all you need.
package YourApp::Attrs;
use strict;
use warnings;
use Moose ();
use Moose::Exporter;
Moose::Exporter->setup_import_methods(
with_caller => [ 'boolean_filter' ],
);
sub boolean_filter {
my ($caller, $name, %options) = @_;
Moose::Meta::Class->initialize($caller)->add_attribute(
$name,
is => 'ro',
isa => 'Bool',
predicate => "has_$name",
%options,
);
}
package YourApp::SomeModule;
use Moose;
use YourApp::Attrs;
boolean_filter($_) for qw(hello goodbye);
See Moose::Exporter. (MooseX::Attributes::Curried *almost* does this, but the
predicate isn't currently possible using it; Sartak, any good ideas?)
Anyway, your example was, I think, slimmed down to the point where I couldn't
see where you planned to use this, but if all you need is an accessor
generator, a role isn't the right concept.
hdp.
