ES 之 06.对象结构赋值

const Tom={
        name:'Tom',
        age:20,
        family:{
            mother:'Norah Jones',
            father:'Richard Jones',
            brother:'Howard Jones',
        }
    }
    //之前已经声明了的时候
    let name
    ({name ,age}=Tom)
    const {mother,father: baba,grandma}=Tom.family  //grandma undefined
    //如果没属性，给默认值

    const {brother,son="have no son"}=Tom.family
    //如果有son,默认值不为undefined,默认值不会生效