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			$func = $module->can( "available_formats" );
		};
		warn($@) if($@); #Warn if there are compilation problems with backend modules
		
		next unless $func;
		
		my $formats_offered = &$func;

		DUMP ( "${module}::available_formats", $formats_offered );

		foreach ( @$formats_offered )
		{
			$Formats { $_ } = $file;
		}
	}

	return [ sort keys %Formats ];
}

#Loads an Any::Renderer backend (safely)
sub _load_module {
	my $file = shift; 
	die ("Backend module name $file looks dodgy - will not load") unless($file =~ /^[\w:]+$/); #Protect against code injection

	my $module = "Any::Renderer::" . $file;  
	unless($INC{"Any/Renderer/$file.pm"}) {
		TRACE ( "Loading renderer backend '" . $module . "'" );
		eval "require " . $module;
		die ("Any::Renderer - problem loading backend module: ". $@ ) if ( $@ );
	}
	return $module;
}

sub TRACE {}
sub DUMP {}

1;

=head1 NAME

Any::Renderer - Common API for modules that convert data structures into strings

=head1 SYNOPSIS

	$renderer = new Any::Renderer ( $format, \%options );
	$string = $renderer->render ( $structure );
	$bool = Any::Renderer::requires_template ( $format );
	$list_ref = Any::Renderer::available_formats ();

=head1 DESCRIPTION

A renderer in this context is something that turns a data structure into a
string.  This includes templating engines, serialisers etc.

This module provides a consistent API to these services so that your
application can generate output in an extensible variety of formats.
Formats currently supported include:

	- XML (via XML::Simple)
	- XML+XSLT
	- Data::Dumper
	- Javascript, Javascript::Anon & JSON
	- UrlEncoded
	- The formats supported by Data::Serializer (e.g. Config::General and Config::Wrest)
	- Any templating language supported by Any::Template

The module will discover any backend modules and offer up their formats.
Once loaded, Any::Renderer will look for a module to handle any new formats it doesn't know about, so adding new formats in a persistent environment won't require the module to be reloaded.
However if you CHANGE which module provides a format you will need to reload Any::Renderer (e.g. send a SIGHUP to modperl).

=head1 METHODS

=over 4

=item $r = new Any::Renderer($format,\%options)

Create a new instance of an Any::Render object using a rendering format of
$format and the options listed in the hash %options (see individual rendering
module documentation for details of which options various modules accept).

=item $string = $r->render($data_structure)

Render the data structure $data_structure with the Any::Renderer object $r.
The resulting string will be returned.

=item $bool = Any::Renderer::requires_template($format)

Determine whether or not the rendering format $format requires a template to
be passed as an option to the object constructor. If the format does require a
template than 1 will be returned, otherwise 0.

=item $list_ref = Any::Renderer::available_formats()

Discover a list of all known rendering formats that the backend modules
provide, e.g. ( 'HTML::Template', 'JavaScript' [, ...]).

=back

=head1 GLOBAL VARIABLES

=over 4

=item @Any::Renderer::LowPriProviders

A list of backend providers which have lower precedence (if there is more than one module which provides a given format).
The earlier things appear in this list, the lower the precedence.

Defaults to C<Data::Serializer> as this provides both XML::Simple and Data::Dumper (which have native Any::Renderer backends).

=back

=head1 WRITING A CUSTOM BACKEND

Back-end modules should have the same public interface as Any::Renderer itself:

=over 4

=item $o = new Any::Renderer::MyBackend($format, \%options);

=item $string = $o->render($data_structure);

=item $bool = requires_template($format)

=item $arrayref = available_formats()

=back

For example:

	package Any::Renderer::MyFormat;
	sub new {
	  my ( $class, $format, $options ) = @_;
	  die("Invalid format $format") unless($format eq 'MyFormat');
	  return bless({}, $class); #More complex classes might stash away options and format 
	}
	
	sub render {
	  my ( $self, $data ) = @_;
	  return _my_format($data);
	}
	
	sub requires_template {
	  die("Invalid format") unless($_[0] eq 'MyFormat');
	  return 0; #No template required
	}
	
	sub handle_formats {
	  return [ 'MyFormat' ]; #Just the one
	}

=head1 SEE ALSO

=over 4

=item All the modules in the Any::Renderer:: distribution

L<http://search.cpan.org/dist/Any-Renderer>.
Each module lists the formats it supports in the FORMATS section.
Many of also include sample output fragments.

=item L<Any::Template>

A templating engine is a special case of a renderer (one that uses a template, usually from a file or string, to control formatting).
If you are considering exposing another templating language via Any::Renderer, instead consider exposing it via Any::Template.
All the templating engines supported by Any::Template are automatically available via Any::Renderer.

=item L<Data::Serializer>