Comments (1)
MMmaXingXing
commented on August 13, 2024
共有特性
typeof与instacne都是js变量类型检测的运算符
typeOf
在js中，typeof是检测基础类型的神器，对于所有引用类型的返回都是object;
instanceOf
当检测某个实例是不是当前对象的实例的时候，就到了instance大展拳脚的时刻了。
instanceOf的实现
// 左边表达式和右边表达式
instanceOf (L, R) {
L = L.__proto__;
R = R.prototype;
While(true) {
if (L == null) return false;
if (L == R) return true;
L = L.__proto__
}
}
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