Struggling with the bug “typeerror: require(…) is not a function” without knowing how to handle it? This instruction will guide you thoroughly what to do and the neatest way to get your job completed.

So, wait for no more but jump right in and get a hold of practical insights!

Why It Happens The Error Typeerror: Require(…) Is Not A Function?

There are actually several reasons you can search for once encountering this error coming up. Amongst those, the three below might be the most feasible to address and resolve your malfunctioning coding.

• Reason #1: Fail to put the semicolon after an IIFE and before the required call.

This is an obvious and frequent mistake people often make when programming their code. You might think it sounds silly, but things like that do happen when your mind is absent. So make sure to double check if all of your syntax is sufficient and functional.

• Reason #2: Calling the require() output when the imported file still lacks a default function export.

The bug can also be derived from your oblivion when importing the file without a default function export. As such, there will be no way for your process to generate the final result if such a lack occurs. 

• Reason #3: Being cyclically dependent (exports and imports between the same modules).

For those who have not yet got familiar, the dependencies in this case might be not at all a benefit to the operation. Instead, you should let these two have a certain separation from each other.

Aside from these above, if your operation is still bumping into such a problem, let’s scroll down and browse for some more acquisitions!

Example Of The Error Typeerror: Require(…) Is Not A Function

In the following coding, the socket.io Server class is returned by require(“socket.io”). However, it’s a class, not an instance, therefore you can’t call it . listen() on.

Running the code:

var http = require('http');

var clientHtml = require('fs').readFileSync('client.html');

var plainHttpServer = http.createServer(function (request, response) {

response.writeHead(200, { 'Content-Type': 'text/html' });

response.end(clientHtml);

}).listen(8080);

var files = require('fs');

var io = require('pocket.io').listen(plainHttpServer);

io.set('origins', ['localhost:8080', '127.0.0.1:8080']);

Output:

var io = require('socket.io').listen(plainHttpServer);

                       ^

TypeError: require(...).listen is not a function

How To Solve Typeerror: Require(…) Is Not A Function

There are a variety of ways you can utilize the Server class depending on what you’re attempting to do. For instance, you could try this to fix the existing error above:

const Server = require('socket.io');


const io = new Server(somePort);

Or to utilize a shared http server:

const io = require('socket.io')(plainHttpServer);

Or this:

const io = require('socket.io')(somePort);

Alternatively, if you are being stuck with the error caused by these reasons we have named early, bear in mind to avoid those in the first place also so you won’t catch them again.

The Bottom Line

Hopefully, this article in discussing the faulty typeerror: require(…) is not a function can somehow get you out of trouble while implementing your programming. 

Now that you have grasped indepthly where to head forward, it’s time to get some practice and enhance your level of troubleshooting! See then!