determine whether a response for the given request exists
determine whether a response for the given request exists
the request
the action to determine existence. will contain true if it does, false otherwise. note that if the resultant IO is true, a subsequent get call may still not return a response
possibly get a response for the given request
possibly get a response for the given request
the request
an IO representing the response, or none if none exists
set a response for the given request, for a TTL
set a response for the given request, for a TTL
the request
the response for the given request
the time to live for the given request/response pair
the IO representing the set action