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输出什么?

javascript
function giveLydiaPizza() {
  return "Here is pizza!"
}

const giveLydiaChocolate = () => "Here's chocolate... now go hit the gym already."

console.log(giveLydiaPizza.prototype)
console.log(giveLydiaChocolate.prototype)

A. { constructor: ...} { constructor: ...} B. {} { constructor: ...} C. { constructor: ...} {} D. { constructor: ...} undefined

答案: D

解析:

常规函数,例如giveLydiaPizza函数,有一个prototype属性,它是一个带有constructor属性的对象(原型对象)。 然而,箭头函数,例如giveLydiaChocolate函数,没有这个prototype属性。 尝试使用giveLydiaChocolate.prototype访问prototype属性时会返回undefined