prototype chain（原型链）ECMA262定义：Every object created by a constructor has an implicit reference (called the object's prototype) to the value of its constructor's \"prototype\
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Object
constructor（构造函数）ECMA262定义：A function object is an object that supports the [[Call]] internal method. A constructor (also referred to as a constructor function) is a function object that supports the [[Construct]] internal method.Each constructor is a function that has a property named \"prototype\
