5.剩余参数

剩余参数语法允许将一个不定数量的参数表示为一个数组

function sum(...args) {
	let total = 0
	args.forEach(item => total += item)
	return total
}
console.log(sum(10, 20))
console.log(sum(10, 20, 30))

剩余参数也可以和解构配合使用

let students = ['zhangsan', 'lisi', 'wangwu']
let [s1,...s2] = students;
console.log(s1)	// 'zhangsan'
console.log(s2)	// ['lisi', 'wangwu']