Why does this javascript sum function report an error?

Question

function sum(...rest) {
    for (rest.length === o) {
        result = 0;
    } else {
        var result = 0;
        for (var v of rest) {
            result += v;
        }
        return result;
    }
}//报错了，自己找不到错误，求帮忙QAQ...最好能给个正确的码？

Answer 1

function sum(...rest) {
    for(rest.length===o){
        result=0;
    }else{
        var result=0;
        for(var v of rest){
            result+=v;
    }
    return result;
    }
}

哥：是 if...else  不是for  else ，还有  rest.length===o,  你写的 是o不是0（零）

把 for(rest.length===o){  这句 改成if(rest.length===0){

Answer 2

for(rest.length===o)写得是o不是0。

Answer 3

for(rest.length===o){
=>
for(rest.length===0){

Answer 4

rest.length===o?Shouldn’t it be 0?

Answer 5

function sum(...rest) {
    var result = 0;
    if(rest.length === 0) {
        result = 0;
    }else{
        for(var v of rest) {
            result += v;
        }
    }
    return result;
}

Answer 6

for(rest.length === o) ?
Funny me

Answer 7

Change the first for to if(rest.length === 0)