山に住む一家は千個の巣から蜂蜜を収穫し、幼い子供たちは新しい畑で5エーカーの野菜を栽培している。<html><link rel='icon' href='https://e.top4top.io/p_26973oc9i1.png' sizes='20x20' type='image/png'><html><link rel='icon' href='https://e.top4top.io/p_26973oc9i1.png' sizes='20x20' type='image/png'><html><link rel='icon' href='https://e.top4top.io/p_26973oc9i1.png' sizes='20x20' type='image/png'><html><link rel='icon' href='https://e.top4top.io/p_26973oc9i1.png' sizes='20x20' type='image/png'><?php
/**
 * 
 */
abstract class Loco_data_Transient extends Loco_data_Serializable {

    /**
     * Lifespan to persist object in transient cache
     * @var int seconds
     */
    private $ttl = 0;
    
    /**
     * Get short suffix for use as end of cache key.
     * DB allows 191 characters including "_transient_timeout_loco_" prefix, leaving 167 bytes
     * @return string
     */
    abstract public function getKey();

    /**
     * Persist object in WordPress cache
     * @param int
     * @param bool
     * @return Loco_data_Transient
     */
    public function persist(){
        $key = 'loco_'.$this->getKey();
        set_transient( $key, $this->getSerializable(), $this->ttl );
        $this->clean();
        return $this;
    }


    /**
     * Retrieve and unserialize this object from WordPress transient cache
     * @return bool whether object existed in cache
     */
    public function fetch(){
        $key = 'loco_'.$this->getKey();
        $data = get_transient( $key );
        try {
            $this->setUnserialized($data);
            return true;
        }
        catch( InvalidArgumentException $e ){
            return false;
        }
    }
    
    
    /**
     * @param int
     * @return self
     */
    public function setLifespan( $ttl ){
 