Question

Here is my CoffeeScript:

jQuery -> 
  $("form").submit (e) -> 
    e.preventDefault() 
    email = $("#email").val() 
    return if email.length == 0 
    $.ajax 
      url: "https://api.kickofflabs.com/v1/1905/subscribe", 
      data: "email=#{email}", 
      dataType: 'jsonp', 
      jsonp: 'jsonp',
      jsonpCallback: 'subscribe_callback', 
      timeout: 2000, 
      error: (a, b, e) -> 
        alert e
        console.log e

subscribe_callback = (data) ->
  console.log(data) 
  alert("Signed up #{data.email}")

Here is a gist as well: https://gist.github.com/1630460

The only way I could get it work, was to move the callback outside of the coffeescript ‘wrap’.

My guess is the the callback can not be accessed because of the wrap. Is there a smart way to work around this?

Answer 1

In standard coffeescript scope the this keyword refers to the global window object. So if you write your function as

this.subscribe_callback = (data) ->
  console.log(data) 
  alert("Signed up #{data.email}")

Then it should be the same as putting it outside of the closure. This is because the closure is invoked with this as a parameter:

(function(this) {
   // your code
})(this)