Question

I don’t like being in situations where I don’t understand why something is working. I feel like I am using a trash bag and a rubber-band to fix a leaky pipe. Since upgrading to rails3.1 I have not been able to get it to work unless I add ‘execjs’ and ‘therubyracer’ to the gemfile. I do not understand what these gems even do. I just read somewhere on stackoverflow that you had to add them for the app to work. Anyone know what these gems are for?

Answer 1

ExecJs – gives you the ability to, well – execute Javascript

RubyRacer – gives you the interface from Ruby to V8 engine.

Both are dependencies of the coffee-script gem, which is used by Rails 3.1 and the asset pipeline.