perl - Moose属性如何“扮演”鼠标角色？

Question

我有一个构成Mouse角色的Moose类。

package My::Moose::Class;
use Moose;
has 'mouse_obj' => (
    is   => 'ro',
    does => 'NotMy::Mouse::Role',
);

package NotMy::Mouse::Role;
use Mouse::Role;

package NotMy::Mouse::Class;
use Mouse;
with 'NotMy::Mouse::Role';

这将导致错误，因为在Moose中鼠标角色未被识别为类型：

my $f = My::Moose::Class->new( mouse_obj => NotMy::Mouse::Class->new );

属性（mouse_obj）不通过类型约束，因为：验证值为NotMy :: Mouse :: Class = HASH（0x23932dc）的'NotMy :: Mouse :: Role'失败（不是isa NotMy :: Mouse :: Role），位于...


有哪些方法可以在不将Mouse对象更改为Moose的情况下正常工作？

Answer 1

您可以执行此操作的一种方法是创建一个自定义类型约束，该约束可以执行所需的检查。

use Moose::Util::TypeConstraints;

subtype 'MouseRole'
    => as 'Object'
    => where sub { $_->does('NotMy::Mouse::Role') };

has 'mouse_obj' => (
    is   => 'ro',
    isa => 'MouseRole', # "isa" not "does"!
);