console.log('params:', params)
T is assignable to S.That is, it is a “consistent subtype”. This is subtyping extended，详情可参考WPS下载最新地址
"You can see his mind is clearly elsewhere."，这一点在体育直播中也有详细论述
MacBook Air delivers the perfect combination of performance and portability for everyone from college students to creative professionals, as well as consumers — and it’s the most popular laptop for business users.