-剩余参数

 // 剩余参数
        const sum = (...args) => {
            let total = 0
            args.forEach(item => total += item)
            return total
        }
        console.log(sum(10, 20)); //30
        console.log(sum(10, 20, 30)); //60

 // 剩余参数
        function sum(a, ...args) {
            console.log(a);
            console.log(args);
        }
        sum(10, 20, 30)

 // 剩余参数于解构赋值
        let colors = ['red', 'pink', 'blue', 'green']
        let [s1, ...s2] = colors
        console.log(s1);
        console.log(s2);