ES9_rest参数与es9_spread扩展运算符

1.ES9 Rest 参数与 spread 扩展运算符

• ES9 rest 参数

function connect({host, port, ...user}) { 
    console.log(host); // 127.0.0.1
    console.log(port); // 3306
    console.log(user); // {username: 'root', password: 'root', type: 'master'}
}

connect({
    host: '127.0.0.1', port: 3306, username: 'root', password: 'root', type: 'master'
});

• ES9 对象合并

// 对象合并
const a = { name: 'https://www.fujuhao.com' }
const b = { es9: 'es9 rest' }

const merge = {...a, ...b};

console.log(merge)
// 打印 {name: 'https://www.fujuhao.com', es9: 'es9 rest'}