dataset

MakeMethods::Utility::Inheritable(3pm)			User Contributed Perl Documentation		    MakeMethods::Utility::Inheritable(3pm)

NAME

       Class::MakeMethods::Utility::Inheritable - "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 overriden 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 );

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

perl v5.10.1							    2004-09-06				    MakeMethods::Utility::Inheritable(3pm)