Event Complete Callbacks with Opal-jQuery
You could use a Promise which is a technique to manage long-term asynchronous events and avoid callback-hell. In regular Opal you would do for example: HTTP.get("url") do |response| puts "got response" end With promises, this becomes: HTTP.get("url").then do |response| puts "got response" end The difference lies in the then which...
Cannot use Ruby Math library with Opal
The Math module is in Opal's stdlib and isn't included in the default runtime (as far as I can tell). Depending on your deployment context, it might be easiest to build the Math module (Opal::Builder.build('math')) into a file. For your specific example, though, you can just use the JS PI...