NAME

         GO::Model::Xref - cross reference to an external database

SYNOPSIS

         my $xrefs = $term->dbxref_list();
         foreach my $xref (@$xrefs) P
           printf "Term %s has an xref %s:%s\n",
                   $term->name, $xref->xref_key, $xref->dbname;
         }

DESCRIPTION

       represents a cross reference to an external database. an Xref is made up of a key (ie the accession
       number, or whatever the value of the unique field being keyed off of is) and a database name. this should
       theorerically be enough to uniquely identify any databased entity.

NOTES

       Like all the GO::Model::* classes, this uses accessor methods to get or set the attributes. by using the
       accessor method without any arguments gets the value of the attribute. if you pass in an argument, then
       the attribuet will be set according to that argument.

       for instance

         # this sets the value of the attribute
         $my_object->attribute_name("my value");

         # this gets the value of the attribute
         $my_value = $my_object->attribute_name();

   xref_key
         Alias   - acc
         Alias   - accession
         Usage   -
         Returns -
         Args    -

        accessor: gets/sets the key/id of the cross reference

   xref_keytype
         Usage   -
         Returns -
         Args    -

        accessor: gets/sets the key/id type of the cross reference

   as_str
         Usage   -
         Returns -
         Args    -

   xref_dbname
         Alias   - dbname
         Usage   -
         Returns -
         Args    -

        accessor: gets/sets the database name of the cross reference

       must be a valid database name

   xref_desc
         Alias   - name
         Usage   -
         Returns -
         Args    -

        accessor: gets/sets the description of the accession no

       useful for interpro

   to_xml
         Usage   - print $xref->to_xml()
         Returns - string
         Args    - indent [integer]

       XML representation; you probably shouldn't call this directly, this will be called by entities that own
       xrefs