# Disallow new require (no-new-require) The `require` function is used to include modules that exist in separate files, such as: ```js var appHeader = require('app-header'); ``` Some modules return a constructor which can potentially lead to code such as: ```js var appHeader = new require('app-header'); ``` Unfortunately, this introduces a high potential for confusion since the code author likely meant to write: ```js var appHeader = new (require('app-header')); ``` For this reason, it is usually best to disallow this particular expression. ## Rule Details This rule aims to eliminate use of the `new require` expression. Examples of **incorrect** code for this rule: ```js /*eslint no-new-require: "error"*/ var appHeader = new require('app-header'); ``` Examples of **correct** code for this rule: ```js /*eslint no-new-require: "error"*/ var AppHeader = require('app-header'); var appHeader = new AppHeader(); ``` ## When Not To Use It If you are using a custom implementation of `require` and your code will never be used in projects where a standard `require` (CommonJS, Node.js, AMD) is expected, you can safely turn this rule off.