JavaScript 对象继承

https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Inheritance_and_the_prototype_chain#%E6%80%BB%E7%BB%93%EF%BC%9A4_%E4%B8%AA%E7%94%A8%E4%BA%8E%E6%8B%93%E5%B1%95%E5%8E%9F%E5%9E%8B%E9%93%BE%

function foo(){}
foo.prototype = {
foo_prop: "foo val"
};
function bar(){}
var proto = new foo;
proto.bar_prop = "bar val";
bar.prototype = proto;
var inst = new bar;
console.log(inst.foo_prop);
console.log(inst.bar_prop);

结果：

foo val
bar val

[sc name="info_blue" title="此时的原型链为"]inst{}–>proto{bar_prop: ‘bar val’}–>foo.prototype{foo_prop:’foo val’}–>Object.prototype{…}–>null[/sc]