I'm following the first steps of the rails guide http://edgeguides.rubyonrails.org/working_with_javascript_in_rails.html#unobtrusive-javascript
The index.html.erb looks like  
    <a href="#" onclick="paintIt(this, '#990000')">Paint it red</a>
    <a href="#" onclick="paintIt(this, '#009900', '#FFFFFF')">Paint it green</a>
    <a href="#" onclick="paintIt(this, '#000099', '#FFFFFF')">Paint it blue</a>
I added coffeescript under app/assets/javascripts/welcome.js.coffee
    paintIt = (element, backgroundColor, textColor) ->
         element.style.backgroundColor = backgroundColor
         if textColor?
             element.style.color = textColor
I get this error:
    Uncaught ReferenceError: paintIt is not defined
I tried chancing paintIt to @paintIt and window.paintIt to no avail. I have a temporary fix of just using plain old javascript in app/assets/javascripts/applications.js, but I wanted to begin using coffeescript. Any suggestions?
 
     
    