apcu-examples

	public static function apcu_check() { if (!self::apcu_enabled()) throw new Exception('APCU module not enabled'); }
	public static function apcu_enabled() { return function_exists('apcu_enabled') && apcu_enabled(); }
	public static function apcu_get($uniqueid) { return \apcu_fetch($uniqueid); }
	public static function apcu_set($uniqueid, $data) { return \apcu_store($uniqueid, $data); }

	public static function apcu_cached_time($uniqueid) {
		$info = apcu_key_info($uniqueid);
		try{
			return $info['mtime']; //https://www.php.net/manual/en/function.apcu-key-info.php
		}
		catch(\Exception $ex){

		}
		return 0;
	}

	// apcu_clear_cache()
	// apcu_exists ($key)
	// apcu_delete ($key)
	/* apcu_cache_info()
		(
			[num_slots] => 4099
			[ttl] => 0
			[num_hits] => 3
			[num_misses] => 1
			[num_inserts] => 7
			[num_entries] => 7
			[expunges] => 16
			[start_time] => 1623695589
			[mem_size] => 20656376
			[memory_type] => mmap
			[cache_list] =>  array of members: https://www.php.net/manual/en/function.apcu-key-info.php
			[deleted_list] =>  []
			[slot_distribution] => [
					[176] => 1     [341] => 1      [940] => 1    ...
			]
		)
		*/

==============
            $timestamp = $this->apcu_cached_time ($uniqFileName);
			if (is_null($timestamp) || $timestamp + $expire_seconds<time() )
			{
				return $default;
			}
			$res = $this->apcu_get($uniqFileName);
			return ( !is_null($res) ? $res : $default );