src/Colorium/Stateful/Provider/Native.php
public function drop($key)
    {
        if($this->has($key)) {
            unset($_SESSION[$this->root][$key]);
            return true;
        }

        return false;
    }
public function drop($key)
    {
        if($this->has($key)) {
            unset($_SESSION[$this->root][$key]);
            return true;
        }

        return false;
    }
Clear value in session

@param string $key
@return bool