Cannot find name ‘require’ Error in TypeScript is a confusing problem that shows up in many ways. What is the cause of it and how to fix it? Let’s read this article to find the best answer.

When Do You Get The Error “Cannot find name ‘require’ Error” In TypeScript?

When you run your program, you easily get the following error:

Cannot find name 'require' Error 

How To Solve The Error “Cannot find name ‘require’ Error” In TypeScript?

Method 1: Define require at the top of TypeScript file

You can define require at the top of your TypeScript file if you only have one file that uses it or if you are using it for demo purposes.

declare var require: any

Method 2: Install the package below

You don’t have to install Definitely Typed or Typings if you are using TypeScript 2.x. All you need to do is installing the package below:

npm install @types/node --save-dev

We will collaborate with those communities to guarantee a smooth transition, and tools such as Typings and tsd will continue to function. Confirm or modify your src/tsconfig.app.json file to ensure the following is present:

… 
"types": [ "node" ], 
"typeRoots": [ "../node_modules/@types" ] 
…

Ensure that no file is on the root app folder and it must be in the src folder. Unless you have defined one of these options, any package under @types is automatically added in your build by default.

Method 3: Add the Webpack types

Another option for you to resolve “Cannot find name ‘require’ Error” in TypeScript problem is that you can add the Webpack types as shown below if you are using Webpack:

npm install --save-dev @types/webpack-env

Under compilerOptions let’s upgrade your tsconfig.json with:

"types": [ 
      "webpack-env" 
    ]

This enables you to perform some Webpack-specific operations and require.ensure.

Method 4: Use typings

It is possible to declare a definition directly from a GitHub project by using typings (DefinitelyTyped’s replacement).

You can run the following command to install typings:

npm install typings -g --save-dev

Next, install the requireJS type definition from the repository of DefinitelyType by the command below:

typings install dt~node --save --global

Method 5: Do as the following command

You can do as the following command:

declare var require: any

You also can try the below command instead ofvar mongoose = require(‘mongoose’):

import mongoose from 'mongoose' // or 
import mongoose = require('mongoose')

Conclusion

Individual solutions provided in these tools are some of the most fundamental for anyone faced with the question Cannot find name ‘require’ Error in TypeScript. If you still need assistance or have basic Python questions, a growing community of people are usually willing to assist you. In addition, we anticipate a more creative day filled with new ideas and code.

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