If you want to pass information to a Camping controller, all you have to do is define the class like this:
class Index < R '/(\d+)'
get(id)
Now whatever was matched by the regex \d+ can be retrieved by the variable id. If you want to pass more than one variable, just chain them like this:
class Index < R '/(\d+)/(\w+)'
get(id, action)
Each of your regex groups will be passed as a variable.
If you forget to add the arguments to the get method, you'll get an error like this: