What's the correct way to use requireJS with typescript?

Question

The examples I have found here and here say to use module(). However, when I compile I get \"warning TS7021: \'module(...)\' is deprecated. Use \'require(...)\' instead.\"

Answer 1

You want the export statement below the class you are creating.

// Base.ts
class Base {

    constructor() {
    }

    public createChildren():void {

    }
}

export = Base;

Then to import and use into another class you would do:

// TestApp.ts
import Base = require("view/Base");

class TestApp extends Base {

    private _title:string = 'TypeScript AMD Boilerplate';

    constructor() {
        super();
    }

    public createChildren():void {

    }
}

export = TestApp;

Answer 2

I have been playing with typescript, trying to integrate it in our existing javascript/requirejs project. As setup, I have Visual Studio 2013 with Typescript for vs v 0.9.1.1. Typescript is configured (in visual studio) to compile modules in amd format.

This is what I have found works for me (there might be a better way of course)

1. Use amd-dependency to tell the typescript compiler adds the required module to the list of components which must be loaded
2. In the constructor of the class being exported, use requirejs’s require function to actually fetch the imported module (at this point this is synchronous because of the previous step). To do this you must reference require.d.ts

As a side note, but since it is in my view essential to typescript, and because it gave me a bit of a headache, in the example I show two ways to export classes which use interfaces. The problem with interfaces is that they are used for type checking, but they produce no real output (the generated .js file is empty), and it causes problems of the type ‘’export of a private class” I have found 2 ways of exporting classes which implement an interface:

1. Simply add an amd-dependency to the interface (as is in the Logger.ts file) And export a typed variable holding a new instance of the class The exported class can be consumed directly (ie myClass.log(‘hello’));
2. Don’t add the amd- dependency to the interface (as is in the Import.ts file) And export a function (ie Instantiate()) which returns a variable of type any holding a new instance of the class The exported class can be consumed via this function (ie myClass.instantiate().log(‘hello’))

It seems like the first option is better: you don’t need to call the instantiate function, plus you get a typed class to work with. The downside is that the [empty] interface javascript file does travel to the browser (but it’s cached there anyway, and maybe you are even using minification in which case this does not matter at all).

In the next blocks of code there are 2 typescript modules loaded with requires (amd): Logger and Import.

ILogger.ts file

interface ILogger {
    log(what: string): void;
}

Logger.ts file

///<reference path="./ILogger.ts"/>

//this dependency required, otherwise compiler complaints of private type being exported
///<amd-dependency path="./ILogger"/>

class Logger implements ILogger {
        formatOutput = function (text) {
            return new Date() + '.' + new Date().getMilliseconds() + ': ' + text;
        };

        log = function (what) {
            try {
                window.console.log(this.formatOutput(what));
            } catch (e) {
                ;
            }
        };
}

//this approach requires the amd-dependency above for the interafce
var exportLogger: ILogger = new Logger();
export = exportLogger;

Using Logger.ts in another ts file(Import.ts)

///<reference path="../../../ext/definitions/require.d.ts"/>

///<amd-dependency path="Shared/Logger"/>
///<amd-dependency path="./IImport"/>

class _Import implements IImport{
    ko: any;
    loggerClass: ILogger;

    constructor() {
        this.ko = require('knockout');//require coming from require.d.ts (in external_references.ts)
        this.loggerClass = require('Shared/Logger');
    }

    init(vm: any) {
        this.loggerClass.log('UMF import instantiated...');
    }
}

////Alternative Approach:
////this approach does not require adding ///<amd-dependency path="./IImport"/>
////this can be consumed as <imported_module_name>.instantiate().init();
//export function instantiate() {
//    var r : any = new _Import();// :any  required to get around the private type export error
//    return r;
//}

//this module can be consumed as <imported_module_name>.init();
var exported: IImport = new _Import();
export = exported;

IImport.ts file

interface IImport {
    init(vm: any): void;
}

To consume the Import module straight from javascript use something like (sorry I have not tried this one, but it should work)

define (['Import'], function (import)
{
    //approach 1
    import.init();

    ////approach 2
    //import.instantiate().init();
});

Answer 3

I would have commented on David's reply to basarat's answer (regarding modules and classes), but I don't have the reputation. I know this question is stale, but I didn't find an answer elsewhere.

I succeeded by using basarat's videos, combined with some other resources, to figure it out for classes like David Thielen needed. Note that I no longer have entries for my ts source files, but I do have amd-dependency and import statements. In Eclipse with palantir's TS plugin, my code completion and ability to jump from usage to definition is working with just the amd-dependency and import statements. The header files still need statements since they have nothing to do with deployment and are only used by the TS compiler. Note also that the .ts file extensions are used for reference statements but not the amd and import statements.

In Utils.ts I have:

///<reference path="headers/require.d.ts" />

export function getTime(){
    var now = new Date();
    return now.getHours()+":"+now.getMinutes()+':'+now.getSeconds();
}

In OntologyRenderScaler I have:

///<reference path="headers/require.d.ts" />

///<reference path="headers/d3.d.ts" />
///<reference path="headers/jquery.d.ts" />

///<amd-dependency path="Utils" />

import Utils = require('./Utils');

export class OntologyRenderScaler {
...
Utils.getTime();
...
}

In OntologyMappingOverview.ts I have:

///<reference path="headers/require.d.ts" />

///<reference path="headers/d3.d.ts" />
///<reference path="headers/jquery.d.ts" />

///<amd-dependency path="Utils" />
///<amd-dependency path="OntologyGraph" />
///<amd-dependency path="OntologyFilterSliders" />
///<amd-dependency path="FetchFromApi" />
///<amd-dependency path="OntologyRenderScaler" />
///<amd-dependency path="GraphView" />

///<amd-dependency path="JQueryExtension" />

import Utils = require('./Utils');
import OntologyGraph = require('./OntologyGraph');
import OntologyRenderScaler = require('./OntologyRenderScaler');
import OntologyFilterSliders = require('./OntologyFilterSliders');
import GraphView = require('./GraphView');

export class OntologyMappingOverview extends GraphView.BaseGraphView implements GraphView.GraphView {
    ontologyGraph: OntologyGraph.OntologyGraph;
    renderScaler: OntologyRenderScaler.OntologyRenderScaler;
    filterSliders: OntologyFilterSliders.MappingRangeSliders;
...
this.renderScaler = new OntologyRenderScaler.OntologyRenderScaler(this.vis);
...
}

I didn't manage (yet!) to get things working like codeBelt suggested above, but an exchange we had on his blog revealed that if I get his approach working (with export MyClass at the bottom of the file), then I would not need to double up the imported identifer with the class name. I suppose it would export the class of interest rather than the namespace it is defined in (the implicit external module, i.e. the TypeScript file name).

Answer 4

For :

When using typescript and requireJS, how do I access a class in one .ts file from another .ts file where requireJS will load the second file and give me the class in the first file? Is there a way to do the standard requireJS approach with two .ts files where the define() at the top loads the second ts file and returns back the object it builds at the end?

simply :

// from file a.ts
export class Foo{

}

// from file b.ts
// import 
import aFile = require('a')
// use: 
var bar = new aFile.Foo();

and compile both files with --module amd flag.

For :

Sort-of the same as question #2. From a java script file, can I use the define() construct on a type script file to get the instantiated object? If so, how?

To use a.ts from b.js simply :

// import as a dependency:
define(["require", "exports", 'a'], function(require, exports, aFile) {

    // use:
    var bar = new aFile.Foo();
});

This is similar to what you would get if you compile b.ts