Using RequireJS exports with CoffeeScript

If you are using the “exports” object in your RequireJS module definition and happen to also be using CoffeeScript then be careful to either return the exports object at the end of the function or explicitly return nothing from the function by typing “return” on the last line. Like so:

define((require, exports, module) -> = 'bar'

If you don’t return nothing or the exports object CoffeeScript will compile this:

define((require, exports, module) -> = 'bar'

…to the following javascript:

define(function(require, exports, module) {
    return = 'bar';

Where the return value will be the string ‘bar’. This is no good because if you return a value from your module definition function, RequireJs uses it instead of the exports object. So when you come to require your module, you’ll be passed a String, rather than an object with a “foo” property as you’d expect.

jQuery CDN as A Named Module In RequireJS

If you want RequireJS to fetch jQuery from a CDN, you’ll need to tell it to do so using the “paths” config:

paths: {
"jquery": ""

As I understand it, if you want to use the local file fallback code a la html5bp you’re out of luck. For those of you who don’t know, the local file fallback code allows you to load jQuery from your own domain if the CDN version fails to load. It looks like this:

<script src=""></script>
<script>window.jQuery || document.write('<script src="js/vendor/jquery-1.8.2.min.js"><\/script>')</script>

Arguably, if you’re using jQuery it is likely to be a global requirement rather than a requirement for one or two modules. The same sort of thing with BackboneJS. It might be better to place these global requirements in the HTML for your pages (before the RequireJS script) to save typing ‘jquery’ and ‘backbone’ in all your module definitions.

Play Framework HTML5 input elements

The built in Play input elements are fairly restrictive in that you can’t specify the input type. I wrote a helper template that you can use to generate input elements which have HTML5 type attributes such as url, email, number, search etc. etc.

All you have to do is call the template method, passing the HTML input type as a parameter. For example:

@helper.html5.input(form("website"), '_label -> "Website:", 'type -> "url")

If you have a form field mapped as a then the template will automatically infer it’s type so you don’t have to pass the type attribute in with your html attributes:

@helper.html5.input(form("email"), '_label -> "Email:")

If your field has the required constraint, e.g. it is a “nonEmptyText” then the template will add the HTML5 “required” attribute to the field as well.

You can get the source code here.