Uncaught ReferenceError: Cannot access 'stocks' before initialization

user_13192933 0
Viewed 6906

I'm trying to import an object into another JS file, and I keep getting this error, Uncaught ReferenceError: Cannot access 'stocks' before initialization. I've declared stocks, and I've imported it correctly, so I can't see what I did wrong. Any help is much appreciated. Thanks.

In the stocks file:

export const stocks = {
    megaCorp: {
        name: 'Mega Corporation',
        value: decideStockValue(),
        portIn: 0,
        document: "mega"
    },

    lunaBake: {
        name: "Luna Baking",
        value: decideStockValue(),
        portIn: 1,
        document: "luna"
    },
}

And in the user file :

import { stocks } from "./stocks.js";

export let user = {
    money: 2000,
    portfolio: [0, 0, 0, 0]
}

function getValue () {
    let value = user.money;
    let cannon = stocks.cannonRock.value * user.portfolio[0];
    let alpha = stocks.alphaComp.value * user.portfolio[1];
    let luna = stocks.lunaBake.value * user.portfolio[2];
    let mega = stocks.megaCorp.value * user.portfolio[3];
    value += cannon;
    value += alpha;
    value += luna;
    value += mega;
    return value;   
}

user.value = getValue();
module javascript
4 Answers

Again Looking at the code it seems syntactically fine, so this is not an answer but i rather want to share a snippet of code to see how it behaves.

The error you shared Uncaught ReferenceError: Cannot access 'variable_name' before initialization is thrown when a lexical variable was accessed before it was initialized ( what is known as a temporal dead zone error), however in the code you share there is nothing that should throw this error.

for example this code will throw this error

const x = 3
function a(){
    console.log(x)
    const x = 5;
}
a()

Assuming indeed that the error originated from the user file, then the following code might solve it. In the code u had getValue was a function expression that should be hoisted ( which again should be fine), but it could be that a bundler you are using is misbehaving.

import { stocks } from "./stocks.js";

const getValue = (stocks, money, portfolio) => {
  let value = money;
  let cannon = stocks.cannonRock.value * portfolio[0];
  let alpha = stocks.alphaComp.value * portfolio[1];
  let luna = stocks.lunaBake.value * portfolio[2];
  let mega = stocks.megaCorp.value * portfolio[3];
  value += cannon;
  value += alpha;
  value += luna;
  value += mega;
  return value;
};

const money = 2000;
const portfolio = [0, 0, 0, 0];
export const user = {
  money,
  portfolio,
  value: getValue(stocks, money, portfolio),
};
user_52879310

After debugging for a little, I closed the server and opened it again. This time, it worked fine. I'm still not sure why the original error happened, but now it's working great. Thanks for everyone's help

user_131929330

This is a classic example of cycle overloading of certain dependancy (c) Sergei Vohmianin

The easiest thing you can do is to move that object into it's separate module just to omit cycle like app => method => app.

user_113171550

I was getting this error ReferenceError: Cannot access 'process' before initialization

when I attempted to do this:

require("dotenv-safe").config();
console.log(process.env);

const DATABASE_URI = process.env.DATABASE_URI;

Turns out, the problem was I was mistakenly declaring process further down in the same file like this:

const process = require("process");

This require was unnecessary since it's available in Node's global context. Deleting that line fixed the problem.

user_10117660
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