public static function fromString($str, $encoding = self::ENCODING){
		
		if(!\is_string($str)){
			throw new \InvalidArgumentException('$str must be a PHP string');
		}
		
		if(!\is_string($encoding)){
			throw new \InvalidArgumentException('$encoding must be a string');
		}
		
		return new static($str, $encoding);
		
	}