function show_loggedin_function( $atts ) {
global $current_user, $user_login;
get_currentuserinfo();
add_filter('widget_text', 'do_shortcode');
if ($user_login)
return '<h4 class="logged-in-user">Hi ' . $current_user -> display_name . ' !</h4>';
else
return '<a href="' . wp_login_url() . ' ">Login</a>';
}
add_shortcode( 'show_loggedin_as', 'show_loggedin_function' );
//Shortcode
[show_loggedin_as]