/**
 * rest参数  用于获取函数的实参 主要是用来代替arguments
 */
//rest
function fn1(...a) {
    console.log(arguments,'1');
    console.log(...arguments,'2');//spread
    console.log(a,'3');
    console.log(...a,'4');
}
fn1(1,2,3,4,5)

function fn2(a,b,...c) {
    console.log(a,'a')
    console.log(b,'b')
    console.log(...c,'c')
    // console.log(...arguments)
}
fn2(3,4,5,6,7,8,9);
// var {}