ReferenceError: Cannot access ‘setTimeout’ before initialization

In my code I am trying to do a javascript exercise. On the second line, I’m trying to get the ogTimeout to store a reference to setTimeout function since I will reassign a new definition to setTimeout.

However I get the error “ReferenceError: Cannot access ‘setTimeout’ before initialization”. I understand that it’s saying that setTimeout should be initialized, but it already is a existing function, so I don’t understand what’s causing the error.

Any help appreciated, thank you!

const timeouts = [];
const ogTimeout = setTimeout; 

let setTimeout = function(method, timeInMs) {
    const timeoutRef = ogTimeout(method, timeInMs);
    timeouts.push(timeoutRef);
}

const clearAllTimeouts = function() {
    while (timeouts.length) {
        const timeoutRef = timeouts.pop();
        clearTimeout(timeoutRef);
    }
}

setTimeout(() => console.log("Callback after 5 seconds."), 5000);

Tried searching referenceerror and its details.

it’s saying that setTimeout should be initialized, but it already is a existing function

No, it’s the let setTimeout that you declared yourself, which is not yet initialised when const ogTimeout = setTimeout runs. Accessing it during the temporal dead zone causes this error.

I will reassign a new definition to setTimeout.

To overwrite the global setTimeout, don’t declare your own variable. Remove the let and write only

setTimeout = function(method, timeInMs) {
    const timeoutRef = ogTimeout(method, timeInMs);
    timeouts.push(timeoutRef);
};

Or to be even more explicit, you can also assign to the property of the global window object:

window.setTimeout = function(method, timeInMs) {
    const timeoutRef = ogTimeout(method, timeInMs);
    timeouts.push(timeoutRef);
};

Btw for this to not break any code, do not forget to also return timeoutRef from your function.