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perlattributesmoose

Perl Moose attributes with minimum, maximum, and default value

Using Moose, it's possible to create attributes having a default value. I have a set of attributes which all have a minimum, maximum and a default value. They are attributes representing a scale (such as Tk::Scale).

Currently, I have at least 3 attributes: current & default:

has 'attr' => (is => 'rw', isa => 'Int', default => 300, lazy => 1, clearer => '_clear_attr');

min:

has 'attr_min' => (is => 'rw', isa => Int', default => 100);

max:

has 'attr_max' => (is => 'rw', isa => Int', default => 1000);

Is it possioble to have all four (current, default, min, max) in one attribute?

Solution

  • I think you want to create a validation rule.

    use Moose::Util::TypeConstraints;

subtype 'ScaleVal',
   as 'Int',
   where { 100 <= $_ && $_ <= 1000 };

has attr => (
   is      => 'rw',
   isa     => 'ScaleVal',
   default => 300,
);