how do I use coffeescript's namespace code in Node?

Question

related: Classes within Coffeescript 'Namespace'

OK so after reading that post I grabbed the namespace function and put it in its own file.

namespace.coffee

namespace = (target, name, block) ->
  [target, name, block] = [(if typeof exports isnt 'undefined' then exports else window), arguments...] if arguments.length < 3
  top    = target
  target = target[item] or= {} for item in name.split '.'
  block target, top
  console.log "created namespace "+ name


root = exports ? window
root.namespace = namespace

and then in Repl:

>  namespace = require('./assets/js/namespace.js').namespace
[Function]

If I toString() it it's correct.

OK, so now I want to use it: ns.coffee (from Sandro's answer)

namespace = require('./namespace.js').namespace

class MyFirstClass
  myFunc: () ->
    console.log 'works'

class MySecondClass
  constructor: (@options = {}) ->
  myFunc: () ->
    console.log 'works too'
    console.log @options

namespace "Project.Something", (exports) ->
  exports.MyFirstClass = MyFirstClass
  exports.MySecondClass = MySecondClass
  console.log 'done with exports'

Then I run it in Repl:

ns = require('./assets/js/ns.js') # compiled ns.coffee
done with exports
created namespace Project.Something
{}

It doesn't appear to be working:

> ns.MyFirstClass                                              
undefined                                                      
> ns.MySecondClass                                             
undefined                                                      
> ns.Project.Something.MySecondClass                           
TypeError: Cannot read property 'Something' of undefined

Am I doing something wrong here?

Aaron Dufour · Accepted Answer · 2013-02-07T22:03:04.320

0

The exports variable is the module.exports for the file you reference it from. So when you call namespace, it changes exports that was returned from requireing namespace, not the one that will be returned from requireing ns.

Notice how namespace takes 3 arguments, but the first line in it essentially makes target optional. If you pass in the target (you probably want exports, or maybe exports ? window if this needs to run in both server and client), then it should do what you want.

edited Feb 07 '13 at 22:03

answered Feb 07 '13 at 00:45

Aaron Dufour

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It seems like if that was the case then I wouldn't see the console log messages from the namespace file, but I do: "created namespace Project.Something" – jcollum Feb 07 '13 at 00:47
@jcollum Why not? The arguments to `namespace` get passed through just fine. – Aaron Dufour Feb 07 '13 at 03:13
Sure, that code is running, but it's clearly not creating the namespace or I'm calling it incorrectly. – jcollum Feb 07 '13 at 21:04
@jcollum See my edit, which should allow you to call it with the current file structure. – Aaron Dufour Feb 07 '13 at 22:03

how do I use coffeescript's namespace code in Node?

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