module Roda::RodaPlugins::Base::RequestMethods

def halt(res=response.finish)

r.halt
response.write 'Hello World!'
response['Content-Type'] = 'text/html'
response.status = 200

r.halt [200, {'Content-Type'=>'text/html'}, ['Hello World!']]

is given, uses the current response.
rack response array of status, headers, and body. If no argument
Immediately stop execution of the route block and return the given 
def halt(res=response.finish)
  throw :halt, res
end