期望赋值或函数调用，但在函数中看到表达式错误

Question

I am having a problem here in React js and it says

Error: Expected an assignment or function call and instead saw an expression

Error is in this function and here is it:

const generateKey = (dataKey) => {
  let output = [];
  let withKeys;

  for (let i = 0; i < dataKey.length; i++){
    withKeys = {
      ...dataKey[i],
      key: i,
    },

    output.push(withKeys);
  }

  return output;
}

I don't know whats the problem in here. Thanks in advance for the help

Answer 1

The problem is inside the for loop. There should be a semicolon instead of comma. Fix it like below:

  for (let i = 0; i < dataKey.length; i++){
    withKeys = {
    ...dataKey[i],
    key: i,
    };
    output.push(withKeys);
  }