JS 查找属性会依次查看原型, 直到找到或者原型为null为止
# 指定someObject原型
someObject.[[Prototype]]
# 读取及设置原型
Object.getPrototypeOf()
Object.setPrototypeOf()
obj.__proto__ # 非标准
__proto__ syntax
A property definition of the form proto: value or “proto”: value does not create a property with the name proto. Instead, if the provided value is an object or null, it points the [[Prototype]] of the created object to that value. (If the value is not an object or null, the object is not changed.)
Note that the proto key is standardized syntax, in contrast to the non-standard and non-performant Object.prototype.proto accessors. It sets the [[Prototype]] during object creation, similar to Object.create — instead of mutating the prototype chain.