man Class::MakeMethods::Utility::Inheritable (3): Inheritable data

SYNOPSIS

package MyClass;
sub new { ... }

package MySubclass;
@ISA = 'MyClass';
...
my $obj = MyClass->new(...);
my $subobj = MySubclass->new(...);

use Class::MakeMethods::Utility::Inheritable qw(get_vvalue set_vvalue );

my $dataset = {};
set_vvalue($dataset, 'MyClass', 'Foobar'); # Set value for class
get_vvalue($dataset, 'MyClass'); # Gets value "Foobar"

get_vvalue($dataset, $obj); # Objects "inherit"
set_vvalue($dataset, $obj, 'Foible'); # Until you override
get_vvalue($dataset, $obj); # Now finds "Foible"

get_vvalue($dataset, 'MySubclass'); # Subclass "inherits"
get_vvalue($dataset, $subobj); # As do its objects
set_vvalue($dataset, 'MySubclass', 'Foozle'); # Until we override it
get_vvalue($dataset, 'MySubclass'); # Now finds "Foozle"

get_vvalue($dataset, $subobj); # Change cascades down
set_vvalue($dataset, $subobj, 'Foolish'); # Until we override again

get_vvalue($dataset, 'MyClass'); # Superclass is unchanged

DESCRIPTION

This module provides several functions which allow you to store values in a hash corresponding to both objects and classes, and to retrieve those values by searching a object's inheritance tree until it finds a matching entry.

This functionality is used by Class::MakeMethods::Standard::Inheritable and Class::MakeMethods::Composite::Inheritable to construct methods that can both store class data and be overridden on a per-object level.

REFERENCE

find_vself

  $vself = find_vself( $dataset, $instance );

Searches $instance's inheritance tree until it finds a matching entry in the dataset, and returns either the instance, the class that matched, or undef.

get_vvalue

  $value = get_vvalue( $dataset, $instance );

Searches $instance's inheritance tree until it finds a matching entry in the dataset, and returns that value

set_vvalue

  $value = set_vvalue( $dataset, $instance, $value );