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* WPSEO_Custom_Taxonomies.
class WPSEO_Custom_Taxonomies {
* Custom taxonomies cache.
protected static $custom_taxonomies = null;
* Gets the names of the custom taxonomies, prepends 'ct_' and 'ct_desc', and returns them in an array.
* @return array The custom taxonomy prefixed names.
public static function get_custom_taxonomies() {
// Use cached value if available.
if ( ! is_null( self::$custom_taxonomies ) ) {
return self::$custom_taxonomies;
self::$custom_taxonomies = [];
$custom_taxonomies = get_taxonomies( $args, 'names', 'and' );
if ( is_array( $custom_taxonomies ) ) {
foreach ( $custom_taxonomies as $custom_taxonomy ) {
self::$custom_taxonomies,
self::add_custom_taxonomies_prefix( $custom_taxonomy ),
self::add_custom_taxonomies_description_prefix( $custom_taxonomy )
return self::$custom_taxonomies;
* Adds the ct_ prefix to a taxonomy.
* @param string $taxonomy The taxonomy to prefix.
* @return string The prefixed taxonomy.
private static function add_custom_taxonomies_prefix( $taxonomy ) {
return 'ct_' . $taxonomy;
* Adds the ct_desc_ prefix to a taxonomy.
* @param string $taxonomy The taxonomy to prefix.
* @return string The prefixed taxonomy.
private static function add_custom_taxonomies_description_prefix( $taxonomy ) {
return 'ct_desc_' . $taxonomy;