2
我寫延伸另一個麋對象類駝鹿對象類:構建一個擴展的駝鹿對象類的順序是什麼?
package MySubClass;
use Moose;
extends MySuperClass;
我有我想自動建立在對象實例化一個屬性:
has 'id' => (
is => 'ro',
isa => 'Str',
builder => '_build_id',
init_arg => undef,
);
sub _build_id {
my $self = shift;
# both ssn and bnn are attributes of MySuperClass
return $self->ssn . $self->bnn;
}
這不起作用除非我將id
設置爲懶惰。爲什麼?
extend
建築物是如何完成的?