Looks cool and all, but what are the benefits of using this over say normal js? I guess if you want to use other libraries, you still need to include them somehow in the build step or can opal take care of that as well?
For anyone else who had no idea what this was, opal[0] is a ruby-to-js transpiler, and AFAIK this is just an example of it being used to make a hello world app.
