Method: (ASSOCIATED-APPLICATION STANDARD-SERVER REQUEST)

Source

(defmethod associated-application ((server standard-server) (request request))
  (loop
     for app in (server.applications server)
     when (starts-with (query-path request) (application.url-prefix app) :test #'char=)
       return app
     finally (error 'inexistent-application-name :query-path (query-path request))))