public function deleteItem($key)
    {
        if (!is_string($key))
            throw new InvalidArgumentException("Invalid key: " . WF::str($key)); 

        unset($this->cache[$key]);
        return true;
    }
public function deleteItem($key)
    {
        if (!is_string($key))
            throw new InvalidArgumentException("Invalid key: " . WF::str($key)); 

        unset($this->cache[$key]);
        return true;
    }
public function deleteItem ( $ key ) { if ( ! is_string ( $ key ) ) throw new InvalidArgumentException ( "Invalid key: " . WF :: str ( $ key ) ) ; unset ( $ this -> cache [ $ key ] ) ; return true ; }
Remove an item from the pool
@param string $key The item to remove
@return bool True
Remove an item from the pool