perl - 对 Moose 属性应用特定检查(除了 Moose 类型)

Question

Moose types很棒，但有时您需要更具体。这些数据类型规则你们都知道:那个参数只能是'A' , 'B'或 'C' ，或者只是一个货币符号，或者必须符合一些正则表达式。

看看下面的例子，它有两个受约束的属性，一个必须是 'm'或 'f' ，另一个必须是有效的 ISO 日期。 Moose 中指定这些约束的最佳方式是什么？我会想到 SQL CHECK子句，但 AFAICS 没有 check Moose 中的关键字。所以我用了trigger ，但听起来不对。有人有更好的答案吗？

package Person;
use Moose;

has gender          => is => 'rw', isa => 'Str', trigger =>
    sub { confess 'either m or f' if $_[1] !~ m/^m|f$/ };
has name            => is => 'rw', isa => 'Str';
has dateOfBirth     => is => 'rw', isa => 'Str', trigger =>
    sub { confess 'not an ISO date' if $_[1] !~ m/^\d\d\d\d-\d\d-\d\d$/ };

no Moose;
__PACKAGE__->meta->make_immutable;

package main;
use Test::More;
use Test::Exception;

dies_ok { Person->new( gender => 42 ) } 'gender must be m or f';
dies_ok { Person->new( dateOfBirth => 42 ) } 'must be an ISO date';

done_testing;

这是我最终使用的:

package Blabla::Customer;
use Moose::Util::TypeConstraints;
use Moose;

subtype ISODate => as 'Str' => where { /^\d\d\d\d-\d\d-\d\d$/ };

has id              => is => 'rw', isa => 'Str';
has gender          => is => 'rw', isa => enum ['m', 'f'];
has firstname       => is => 'rw', isa => 'Str';
has dateOfBirth     => is => 'rw', isa => 'ISODate';

no Moose;
__PACKAGE__->meta->make_immutable;

这是 Moose 版本 1.19，以防万一。我收到以下错误警告 subtype as => 'Str', where => { ... }我错误引入的语法: Calling subtype() with a simple list of parameters is deprecated .所以我不得不根据精美的手册对其进行一些更改。

Answer 1

只需定义您自己的子类型，然后使用它。

package Person;

use Moose::Util::TypeConstraints;

use namespace::clean;
use Moose;

has gender => (
  is => 'rw',
  isa => subtype(
    as 'Str',
    where { /^[mf]$/ }
  ),
);
has name => (
  is => 'rw',
  isa => 'Str'
);
has dateOfBirth => (
  is => 'rw',
  isa => subtype(
    as 'Str',
    where { /^\d\d\d\d-\d\d-\d\d$/ }
  ),
);

no Moose;
__PACKAGE__->meta->make_immutable;
1;

package main;
use Test::More;
use Test::Exception;

dies_ok { Person->new( gender => 42 ) } 'gender must be m or f';
dies_ok { Person->new( dateOfBirth => 42 ) } 'must be an ISO date';

done_testing;

或者您可以使用 MooseX::Types模块。

package Person::TypeConstraints;

use MooseX::Types::Moose qw'Str';
use MooseX::Types -declare => [qw'
  Gender ISODate
'];

subtype Gender, (
  as Str,
  where { /^[mf]$/ },
);

subtype ISODate, (
  as Str,
  where { /^\d\d\d\d-\d\d-\d\d$/ }
);
1;

package Person:

use MooseX::Types::Moose qw'Str';
use Person::TypeConstraints qw'Gender ISODate';

use namespace::clean;
use Moose;

has gender => (
  is => 'rw',
  isa => Gender,
);
has name => (
  is => 'rw',
  isa => Str,
);
has dateOfBirth => (
  is => 'rw',
  isa => ISODate,
);

no Moose;
__PACKAGE__->meta->make_immutable;
1;