Unless v1.9.1 和 if 相反 —— 条件 不满足 时执行代码块。 输入 {% unless product.title == "Awesome Shoes" %} These shoes are not awesome.{% endunless %} 输出 These shoes are not awesome. 等价于执行下面的代码: {% if product.title != "Awesome Shoes" %} These shoes are not awesome.{% endif %}