I'm using Rails 3.2.9. When I add CoffeeScript code to a .js.coffee file in the /app/assets/javascripts directory, I get the resulting JavaScript in all of my webpages. The problem is all the JavaScript is wrapped in:

(function() {
  // my code
}).call(this);

So any methods I define are not visible in any other CoffeeScript code I write in other files. What's the proper way to write a set of reusable CoffeeScript classes and methods with Rails?

I'm using Rails 3.2.9. When I add CoffeeScript code to a .js.coffee file in the /app/assets/javascripts directory, I get the resulting JavaScript in all of my webpages. The problem is all the JavaScript is wrapped in:

(function() {
  // my code
}).call(this);

So any methods I define are not visible in any other CoffeeScript code I write in other files. What's the proper way to write a set of reusable CoffeeScript classes and methods with Rails?

• javascript
• ruby-on-rails
• ruby-on-rails-3
• coffeescript
• ruby-on-rails-3.2

2 Answers 2

The simplest thing to do is to namespace all your classes. If your application is called "app" then in your initialization code before anything else happens:

// Set up the namespace.
window.app = { }

and then in all your .coffee files:

class app.Pancakes
    #...

Then you'd have a global namespace and you'd reference everything through that namespace:

pancakes = new app.Pancakes

Similarly for simple functions:

app.where_is = (pancakes, house) -> ...

# And elsewhere...
x = app.where_is(...)

There are various ways of setting up and partially hiding the namespace but they're all variations on the above and simple namespacing plays nicely with the Rails asset pipeline.

Also, you can define classes within the coffeescript files like this:

class this.Person
  constructor: (attr = {}) ->
    ...

In that way, the definitions are attached to the global namespace.