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YAML::Node(3)		       User Contributed Perl Documentation		    YAML::Node(3)

NAME
       YAML::Node - A generic data node that encapsulates YAML information

SYNOPSIS
	   use YAML;
	   use YAML::Node;

	   my $ynode = YAML::Node->new({}, 'ingerson.com/fruit');
	   %$ynode = qw(orange orange apple red grape green);
	   print Dump $ynode;

       yields:

	   --- !ingerson.com/fruit
	   orange: orange
	   apple: red
	   grape: green

DESCRIPTION
       A generic node in YAML is similar to a plain hash, array, or scalar node in Perl except
       that it must also keep track of its type. The type is a URI called the YAML type tag.

       YAML::Node is a class for generating and manipulating these containers.	A YAML node (or
       ynode) is a tied hash, array or scalar. In most ways it behaves just like the plain thing.
       But you can assign and retrieve and YAML type tag URI to it. For the hash flavor, you can
       also assign the order that the keys will be retrieved in. By default a ynode will offer
       its keys in the same order that they were assigned.

       YAML::Node has a class method call new() that will return a ynode. You pass it a regular
       node and an optional type tag. After that you can use it like a normal Perl node, but when
       you YAML::Dump it, the magical properties will be honored.

       This is how you can control the sort order of hash keys during a YAML serialization. By
       default, YAML sorts keys alphabetically. But notice in the above example that the keys
       were Dumped in the same order they were assigned.

       YAML::Node exports a function called ynode(). This function returns the tied object so
       that you can call special methods on it like ->keys().

       keys() works like this:

	   use YAML;
	   use YAML::Node;

	   %$node = qw(orange orange apple red grape green);
	   $ynode = YAML::Node->new($node);
	   ynode($ynode)->keys(['grape', 'apple']);
	   print Dump $ynode;

       produces:

	   ---
	   grape: green
	   apple: red

       It tells the ynode which keys and what order to use.

       ynodes will play a very important role in how programs use YAML. They are the foundation
       of how a Perl class can marshall the Loading and Dumping of its objects.

       The upcoming versions of YAML.pm will have much more information on this.

AUTHOR
       Ingy doet Net <ingy@cpan.org>

COPYRIGHT
       Copyright (c) 2006, 2011-2012. Ingy doet Net. All rights reserved.

       Copyright (c) 2002. Brian Ingerson. All rights reserved.

       This program is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself.

       See <http://www.perl.com/perl/misc/Artistic.html>

POD ERRORS
       Hey! The above document had some coding errors, which are explained below:

       Around line 296:
	   Non-ASCII character seen before =encoding in 'doet'. Assuming UTF-8

perl v5.16.3				    2012-07-13				    YAML::Node(3)
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