TYPEMAP

GdomeDocument *         G_OBJECT
GdomeXPathResult *         G_OBJECT

INPUT
G_OBJECT
    if( sv_isobject($arg) && (SvTYPE(SvRV($arg)) == SVt_PVMG) )
            $var = ($type)SvIV((SV*)SvRV( $arg ));
    else{
            $var = NULL;
    }
