如何将Wordpress用户变量数据插入主题函数？

How can I add the current Wordpress users Email Address into my code below? This is for the theme functions theme.

add_filter( 'facetwp_preload_url_vars', function( $url_vars ) {
if ( 'directory/page' == FWP()->helper->get_uri() ) {
    if ( empty( $url_vars['email_address'] ) ) {
        $url_vars['email_address'] = array( 'INSERT CURRENT USER EMAIL ADDRESS' );
    }
}
return $url_vars;

} );

Currently: INSERT CURRENT USER EMAIL ADDRESS Needed Example: forexample@domain.com