apcu_exists Checks if entry exists &reftitle.description; mixedapcu_exists mixedkeys Checks if one or more APCu entries exist. &reftitle.parameters; keys A string, or an array of strings, that contain keys. &reftitle.returnvalues; Returns &true; if the key exists, otherwise &false; Or if an array was passed to keys, then an array is returned that contains all existing keys, or an empty array if none exist. &reftitle.examples; ]]> &example.outputs.similar; bool(true) ["bar"]=> bool(true) } ]]> &reftitle.seealso; apcu_cache_info apcu_fetch