src/curlient/StringFilter.php
public static function sub($content, ...$args) {
		array_unshift($args, 'sub');

		return self::getInstance()->filter($content, [$args]);
	}
public static function sub($content, ...$args) {
		array_unshift($args, 'sub');

		return self::getInstance()->filter($content, [$args]);
	}
取中间的字符串.

@param string $content
@param array  ...$args

@return string