Typescript + nodeJS: import of fs becomes string

Question

Typescript + nodeJS: import of fs becomes string

I'm new with Typescript and with NodeJS.

For some reason this:

GetMenuDataCommand.ts

"use strict";

import fs = module("fs")

becomes this:

GetMenuDataCommand.js

  var fs = "fs";

Typescript - i love you - but why?

node.js
requirejs
typescript

Answer 1

I'm using TypeScript 0.9 the following code:

/// <reference path="node.d.ts" />

import fs = require("fs");

fs.appendFile('name.txt', 'Some data');

Produces the following identical output:

var fs = require("fs");

fs.appendFile('name.txt', 'Some data');

(In CommonJS mode - in AMD mode it does the below...)

define(["require", "exports", "fs"], function(require, exports, __fs__) {
    var fs = __fs__;

    fs.appendFile('name.txt', 'Some data');
});

Answer 2

Are you referencing the node.d.ts file correctly? If TypeScript doesn't have a reference to the definition file for your import, it'll generate a string for the import instead of the expected code.

For example, I had the following:

import passport = require('passport');

and that was generating:

var passport = "passport";

Turns out I'd forgotten to reference the definition file. Adding a reference at the top of the file solved the problem:

/// <reference path="../../definitions/passport.d.ts" />

Arguably you should spot it easily because the TypeScript compiler would throw an error, but 0.9.x is somewhat bug-ridden and it doesn't always catch everything.

Answer 3

Not sure if its related but in ts 0.9.x use require instead of module keyword :

"use strict";

import fs = require("fs")