2009/12/22 Shlomi Fish <[email protected]>:
> On Tuesday 22 Dec 2009 15:10:06 Dermot wrote:
>> 2009/12/22 Shlomi Fish <[email protected]>:
>> > Hi Dermot!
>>
>> Hi Shlomi,
>>
>
> Hi.
>
>> >> package Media;
>> >>
>> >> use metaclass (
>> >> metaclass => 'Moose::Meta::Class',
>> >> error_class => 'Moose::Error::Croak',
>> >> );
>> >> use Moose;
>> >> use AppConfig;
>> >> use FindBin qw($Bin);
>> >> use lib "$Bin/../";
>> >>
>> >>
>> >> has 'config' => (
>> >> is => 'ro',
>> >> lazy => 1,
>> >> default => sub{ {} },
>> >> trigger => \&_get_config,
>> >> );
>>
>> ...
>>
>> > This doesn't seem to do what you want. I think you want a meaningful
>> > "default" or "builder" instead:
>> >
>> > <<<<<<<<<
>> > builder => Str
>> > The value of this key is the name of the method that will
>> > be called to obtain the value used to initialize the attribute. See the
>> > builder option docs in Class::MOP::Attribute and/or
>> > Moose::Cookbook::Basics::Recipe8 for more information.
>> >
>> >> sub _get_config {
>> >> my $self = shift;
>> >> my $config = AppConfig->new( {
>> >> CREATE => 0,
>> >> });
>> >> $config->define('media_root',{ ARGCOUNT=> 'ARGCOUNT_ONE' });
>> >> my $config_file = "$Bin/../media.conf";
>> >> $self->croak("Can't open config file $config_file\n") if (! -e
>> >> $config_file);
>> >> $config->file($config_file);
>> >> return $config;
>> >> }
>> >
>> > Again, this should most probably be a "builder" method.
>>
>> Okay, I'll take that advice. So now I have
>>
>> has 'config' => (
>> is => 'ro',
>> lazy_build => 1,
>> );
>>
>> sub _build_config {
>> my $self = shift;
>> my $config = AppConfig->new( {
>> CREATE => 1,
>> GLOBAL => {
>> ARGCOUNT => 1,
>> },
>> });
>> my $config_file = "$Bin/../spl.conf";
>> $self->croak("Can't open config file $config_file\n") if (! -e
>> $config_file);
>> $config->file($config_file);
>> return $config;
>> }
>
> I don't see where you've associated << _build_config >> with the 'config'
> attribute. Or is this some kind of undocumented default or a property of your
> meta-class.
>From Moose pod:
lazy_build => (0|1)
Automatically define lazy => 1 as well as builder =>
"_build_$attr", clearer => "clear_$attr', predicate => 'has_$attr'
unless they are already defined.
so lazy_build is shorthand for
has config => ( is => 'ro', builder=> _build_foo);
sub _build_foo {}
Is will take all $attr and prepend _build_ to it and look for the
relevant method, in this case "_build_config". Least that what I took
it to mean.
Dp.
>> Elkles cake....poor I know.
>>
>
> What is Elkles? http://www.google.com/search?q=elkles does not seem to know. I
> know what an "Elk" is.
Eccles. I did say it was poor. Perhaps I should have said shockingly
poor and tenuous.
Dp.
