CODEWITHSUNDEEP
javascriptnode.js
laggingreflex
laggingreflex

Reputation: 34687

Exporting a class results in "TypeError: ... is not a function"

I have node.js app in which I have a class.js module in which 

var MyClass = module.exports.MyClass = function MyClass(){}

Object.defineProperty(MyClass, 'MyArray', ['value1','value2']);

MyClass.prototype.MyFunction = function(){
    //---
}

Then I require it in my main app.js

var MyClass = require('./class.js');

var myInstance = new MyClass(); // TypeError: object is not a function

but it throws that error when I try to instantiate it with new. What am I doing wrong here? I've tried a lot of alterations but none works, but I do know that it(or something close to it) used to work..

Upvotes: 0

Views: 929

Answers (1)

Louis
Louis

Reputation: 151561

var MyClass = require('./class.js').MyClass;

You have to assign to MyClass the MyClass member which you set on the exports object. Otherwise you are invoking new with the module instance returned by require.

Otherwise you could export like this:

var MyClass = module.exports = exports = function MyClass(){}

and keep your require statement as is. In this case you are exporting one and only one function from your module. (Technically, you don't need to assign to exports in the line above. However, if you don't then exports ceases to be an alias of module.exports. I prefer to keep them in sync.)

Upvotes: 2

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