This is a simplified version of a class I have.
It does the job. It returns the correct object type for the parsed email and leads a profitable life.

But.
I feel I've missed a trick. My OO design skills are poor crap. But hey, I'm a Unix Sys admin so for the Perl I write OO is usually a pointless overhead, especially one liners :-).

Seriously, I wonder if my parsing classes should be sub classes of a parent as they all have the same attributes (nearly) and only have the one method? So it would seem so but I'm not sure what benefit that would give me?

Also am I complicating things by returning objects of a different class? I think that my severity attribute is only there so I don't have to call ref $obj in the calling code.

As an aside I'm reading http://designpatternsinruby.com/ and since Ruby is Perl Lite I find it a readable and informative. Anyone know of a decent Perl design patterns reference? 

package MailReader;

BEGIN {
push @INC, "U:\Perl";    
}

use Moose;
use Harmless;
use Critical;
use UnSeen;

has 'severity' => (
    is      => 'rw',
    isa     => 'Str',
    default => 'unknown'
);

has 'mailbody' => (
    is      => 'rw',
    isa     => 'Str'
);

sub parse_body {
    my $self = shift;
         
    # Look for Segmentation faults
    my $cm = Critical->new(data => $self->mailbody());
    $cm->analysis();
    if ($cm->is_critical) {
      $self->severity('critical');
      return $cm;
    }

    # harmless
    my $hl = Harmless->new(data => $self->mailbody());
    $hl->analysis();
    if ($hl->is_harmless) {
       $self->severity('harmless');
       return $hl;
    }

    # Still here then not seen this before
    my $us = UnSeen->new(data => $self->mailbody());
    $us->analysis();
    $self->severity('unknown');
    return $us;
}

__PACKAGE__->meta->make_immutable;
1;

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In reply to OO Design question. by Anonymous Monk

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