private function buildBlockDirective($context, $contextValue, $lines)
    {
        $class = 'WebHelper\Parser\Directive\BlockDirective';
        $known = $this->parser->getServer()->getKnownDirectives();
        if (in_array($context, array_keys($known))) {
            if (isset($known[$context]['class'])) {
                $class = 'WebHelper\Parser\Directive\\'.$known[$context]['class'];
            }
        }
        $block = new $class($context, $contextValue);
        foreach ($lines as $directive) {
            $block->add($directive);
        }

        return $block;
    }