oracular (3) XML::Namespace.3pm.gz

NAME

       XML::Namespace - Simple support for XML Namespaces

SYNOPSIS

        Example 1: using XML::Namespace objects

           use XML::Namespace;

           my $xsd = XML::Namespace->new('http://www.w3.org/2001/XMLSchema#');

           # explicit access via the uri() method
           print $xsd->uri();           # http://www.w3.org/2001/XMLSchema#
           print $xsd->uri('integer');  # http://www.w3.org/2001/XMLSchema#integer

           # implicit access through AUTOLOAD method
           print $xsd->integer;         # http://www.w3.org/2001/XMLSchema#integer

        Example 2: importing XML::Namespace objects

           use XML::Namespace
               xsd => 'http://www.w3.org/2001/XMLSchema#',
               rdf => 'http://www.w3.org/1999/02/22-rdf-syntax-ns#';

           # xsd and rdf are imported subroutines that return
           # XML::Namespace objects which can be used as above

           print xsd->uri('integer');   # http://www.w3.org/2001/XMLSchema#integer
           print xsd->integer;          # http://www.w3.org/2001/XMLSchema#integer

DESCRIPTION

       This module implements a simple object for representing XML Namespaces in Perl.  It provides little more
       than some syntactic sugar for your Perl programs, saving you the bother of typing lots of long-winded
       URIs.  It was inspired by the Class::RDF::NS module distributed as part of Class::RDF.

   Using XML::Namespace Objects
       First load the XML::Namespace module.

           use XML::Namespace;

       Then create an XML::Namespace object.

           my $xsd = XML::Namespace->new('http://www.w3.org/2001/XMLSchema#');

       Then use the uri() method to return an absolute URI from a relative path.

           print $xsd->uri('integer'); # http://www.w3.org/2001/XMLSchema#integer

       Alternately, use the AUTOLOAD method to map method calls to the uri() method.

           print $xsd->integer;        # http://www.w3.org/2001/XMLSchema#integer

   Importing XML::Namespace Objects
       When you "use" the XML::Namespace module, you can specify a list of namespace definitions.

           use XML::Namespace
               xsd => 'http://www.w3.org/2001/XMLSchema#',
               rdf => 'http://www.w3.org/1999/02/22-rdf-syntax-ns#';

       This defines the "xsd" and "rdf" subroutines and exports them into the calling package.  The subroutines
       simply return XML::Namespace objects initialised with the relevant namespace URIs.

           print xsd->uri('integer');  # http://www.w3.org/2001/XMLSchema#integer
           print xsd->integer;         # http://www.w3.org/2001/XMLSchema#integer

   Overloaded Stringification Method
       The XML::Namespace module overloads the stringification operator to return the namespace URI.

           my $xsd = XML::Namespace->new('http://www.w3.org/2001/XMLSchema#');

           print $xsd;           # http://www.w3.org/2001/XMLSchema#

METHODS

   new($uri)
       Constructor method which creates a new XML::Namespace object.  It expects a single argument denoting the
       URI that the namespace is to represent.

           use XML::Namespace;

           my $xsd = XML::Namespace->new('http://www.w3.org/2001/XMLSchema#');

   uri($path)
       When called without arguments, this method returns the URI of the namespace object, as defined by the
       argument passed to the new() constructor method.

           $xsd->uri();          # http://www.w3.org/2001/XMLSchema#

       An argument can be passed to indicate a path relative to the namespace URI.  The method returns a simple
       concatenation of the namespace URI and the relative path argument.

           $xsd->uri('integer'); # http://www.w3.org/2001/XMLSchema#integer

   import($name,$uri,$name,$uri,...)
       This method is provided to work with the Exporter mechanism.  It expects a list of "($name, $uri)" pairs
       as arguments.  It creates XML::Namespace objects and accessor subroutines that are then exported to the
       caller's package.

       Although not intended for manual invocation, there's nothing to stop you from doing it.

           use XML::Namespace;

           XML::Namespace->import( xsd => 'http://www.w3.org/2001/XMLSchema#' );

           xsd()->integer;   # http://www.w3.org/2001/XMLSchema#integer

       Note that the parentheses are required when accessing this subroutine.

           xsd()->integer;     # Good
           xsd->integer;       # Bad

       Unlike those that are defined automatically by the Importer, Perl doesn't know anything about these
       subroutines at compile time.  Without the parentheses, Perl will think you're trying to call the
       "integer" method on an unknown "xsd" package and you'll see an error like:

           Can't locate object method "integer" via package "xsd"

       That's why it's better to define your namespaces when you load the XML::Namespace module.

           use XML::Namespace
               xsd => 'http://www.w3.org/2001/XMLSchema#';

           xsd->integer;       # Good

   AUTOLOAD
       The module defines an AUTOLOAD method that maps all other method calls to the uri() method.  Thus, the
       following return the same value.

           $xsd->uri('integer'); # http://www.w3.org/2001/XMLSchema#integer
           $xsd->integer;        # http://www.w3.org/2001/XMLSchema#integer

AUTHOR

       Andy Wardley <mailto:abw@cpan.org>

VERSION

       This is version 0.02 of XML::Namespace.

COPYRIGHT

       Copyright (C) 2005 Andy Wardley.  All Rights Reserved.

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

SEE ALSO

       The Class::RDF::NS module, distributed as part of Class::RDF, provided the inspiration for the module.
       XML::Namespace essentially does the same thing, albeit in a slightly different way.  It's also available
       as a stand-alone module for use in places unrelated to RDF.

       The XML::NamespaceFactory module also implements similar functionality to XML::Namespace, but instead
       uses the JClark notation (e.g. "{http://foo.org/ns/}title").