if (a == 1 && a == 2 && a == 3) {
console.log("hello");
}
答案1
var a = [1, 2, 3];
a.join = a.shift;
答案2
var a = {
default : 0,
toString:function () {
return ++ this.default
}
}
答案3 (不是单独js文件中,没有window对象)
var _default = 0;
Object.defineProperty(window,"a",{
get () {
return ++ _default
}
})
答案4 (单独js文件,没有window对象,但是有global)
var _default = 0;
Object.defineProperty(global, "a", {
get() {
return ++_default;
},
});
参考 https://www.bilibili.com/video/BV1aV41187cU