NAME

POOF - Perl extension that provides stronger typing, encapsulation and inheritance.

SYNOPSIS

    package MyClass;
    
    use base qw(POOF);
    
    # class properties
    sub Name : Property Public
    {
        {
            'type' => 'string',
            'default' => '',
            'regex' => qr/^.{0,128}$/,
        }
    }
    
    sub Age : Property Public
    {
        {
            'type' => 'integer',
            'default' => 0,
            'min' => 0,
            'max' => 120,
        }
    }
    
    sub marritalStatus : Property Private
    {
        {
            'type' => 'string',
            'default' => 'single',
            'regex' => qr/^(?single|married)$/
            'ifilter' => sub
            {
                my $val = shift;
                return lc $val;
            }
        }
    }
    
    sub spouse : Property Private
    {
        {
            'type' => 'string',
            'default' => 'single',
            'regex' => qr/^.{0,64}$/,
            'ifilter' => sub
            {
                my $val = shift;
                return lc $val;
            }
        }
    }
    
    sub opinionAboutPerl6 : Property Protected
    {
        {
            'type' => 'string',
            'default' => 'I am so worried, I don\'t sleep at night.'
        }
    }
      
    # class methods
    sub MarritalStatus : Method Public
    {
        my ($obj,$requester) = @_;
        if ($requester eq 'nefarious looking stranger')
        {
            return 'non of your business';
        }
        else
        {
            return $obj->{'marritalStatus'}
        }
    }
    
    sub GetMarried : Method Public
    {
        my ($obj,$new_spouse) = @_;
        
        $obj->{'spouse'} = $new_spouse;
        
        if ($obj->Errors)
        {
            my $errors = $obj->GetErrors;
            if (exists $errors->{'spouse'})
            {
                die "Problems, the marrige is off!! $errors->{'spouse'}\n";
                return 0;
            }
        }
        else
        {
            $obj->{'marritalStatus'} = 'married';
            return 1;
        }
    }
    
    sub OpinionAboutPerl6 : Method Public Virtual
    {
        my ($obj) = @_;
        return "Oh, great, really looking forward to it. It's almost here :)";
    }
    
    sub RealPublicOpinionAboutPerl6 : Method Public
    {
        my ($obj) = @_;
        return $obj->OpinionAboutPerl6;
    }
  
    

DESCRIPTION

This module attempts to give Perl a more formal OO implementation framework. Providing a distinction between class properties and methods with three levels of access (Public, Protected and Private). It also restricts method overriding in children classes to those properties or methods marked as "Virtual", in which case a child class can override the method but only from its own context. As far as the parent is concern the overridden method or property still behaves in the expected way from its perspective.

Take the example above:

Any children of MyClass can override the method "OpinionAboutPerl6" as it is marked "Virtual":

    # in child

    sub OpinionAboutPerl6 : Method Public
    {
        my ($obj) = @_;
        return "Dude, it's totally tubular!!";
    }
    

However if the public method "RealPublicOpinionAboutPerl6" it's called then it would in turn call the "OpinionAboutPerl6" method as it was defined in MyClass, because from the parents perspective the method never changed. I believe this is crucial behavior and it goes along with how the OO principles have been implemented in other popular languages like Java, C# and C++.

Properties

Class properties are defined by use of the "Property" function attribute. Properties like methods have three levels of access (see. Access Levels) which are Public, Protected and Private. In addition to the various access levels properties can be marked as Virtual, which allows them to be overriden in sub-clases and gives them visibility through the entire class hierarchy.

type

regex

orm

Property access modifiers

Property virtual

Property

Property

Methods

EXPORT

None.

SEE ALSO

Although this framework is currently being used in production environments, I cannot accept responsibility for any damages cause by this framework, use only at your own risk.

Documentation for this module is a work in progress. I hope to be able to dedicate more time and created a more comprehensive set of docs in the near future. Anyone interested in helping with the documentation, please contact me at bmillares@cpan.org.

AUTHOR

Benny Millares<lt>bmillares@cpan.org<gt>

COPYRIGHT AND LICENSE

Copyright (C) 2007 by Benny Millares

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.8 or, at your option, any later version of Perl 5 you may have available.