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Node.js VM Module

❮ Built-in Modules


Example

Run some JavaScript code in a "virtual machine":

var vm = require('vm');
var myObj = { name: 'John', age: 38 };
vm.createContext(myObj);

vm.runInContext('age += 1;', myObj);

console.log(myObj);
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Definition and Usage

The VM module provides a way of executing JavaScript on a virtual machine, almost like eval() in JavaScript.


Syntax

The syntax for including the VM module in your application:

var vm = require('vm');

VM Properties and Methods

Method Description
createContext() Prepares a virtual machine, or sandbox, where you can execute scripts
isContext() Returns true if the specified sandbox has been created by the createContext() method
runInContext() Executes JavaScript code in the specified context, and returns the result
runInDebug() Executes JavaScript inside the debug context
runInNewContext() Executes JavaScript code in a new context, and returns the result
runInThisContext() Executes JavaScript code in the global context, and returns the result

❮ Built-in Modules