Question

This javascript code is working fine.

  function goToByScroll(id){
     $('html,body').animate({scrollTop: $("#"+id).offset().top - 50},'slow');
  }

I’m having a hard time with its CoffeScript version. I had the following code on application.js.coffee.

  goToByScroll = (id) ->
    $("html,body").animate ->
      scrollTop: $("#" + id).offset().top - 50
    , "slow"

But I get the error

ReferenceError: Can't find variable: goToByScroll

Any idea what may be causing the error?

Answer 1

What Jordan said is correct: you’ll need to somehow export your function
to a globally-accessible scope or compile your CoffeeScript with the bare
flag, preventing the output from being wrapped in an anonymous function.

Additionally, you’ve got a bit of a bug in your CoffeeScript: you’re passing
a callback to jQuery.animate, not an object literal like you do in the
JavaScript code. For equivalent behavior, you probably want something like
this:

goToByScroll = (id) ->
    $("html,body").animate
        # CoffeeScript supports string interpolation, that's what the #{}
        # syntax does
        scrollTip: $("##{id}").offset().top - 50
    , "slow"

# Then, export it by attaching it to the window or some object accessible
# outside this scope
window.goToByScroll = goToByScroll