remove tryagain, fix USERSDONTMATCH error message

lib/server/connection.ml

@@ -68,7 +68,6 @@ let reply t (num, params) =
     (Msg.make num (target :: params)
        ~prefix ~always_trailing)
 
-let tryagain cmd          = "263", [cmd; "Please wait a while and try again."]
 let away nick text        = "301", [nick; text]
 let nosuchnick tgt        = "401", [tgt; "No such nick/channel"]
 let nosuchchannel tgt     = "403", [tgt; "No such channel"]
@@ -89,8 +88,7 @@ let unknownmode chr       = "472", [String.make 1 chr; "is an unknown mode char
 let noprivileges          = "481", ["Permission Denied- You're not an IRC operator"]
 let chanoprivsneeded chan = "482", [chan; "You're not channel operator"]
 let umodeunknownflag      = "501", ["Unknown MODE flag"]
-let usersdontmatch_set    = "502", ["Can't change mode for other users"]
-let usersdontmatch_get    = "502", ["Can't view mode for other users"]
+let usersdontmatch x      = "502", [Fmt.str "Can't %s mode for other users" x]
 
 
 (* permission checking *)
@@ -100,9 +98,6 @@ let require_registered t : user result =
   | Some me -> Ok me
   | None -> Error notregistered
 
-let require_same_user user me =
-  if (user : user) == me then Ok () else Error usersdontmatch_get
-
 let require_membership chan me =
   match Router.membership chan me with
   | mem -> Ok mem
@@ -179,13 +174,13 @@ let set_member_priv ~from mem priv =
     mem.mem_priv <- priv
 
 let on_get_user_mode user me =
-  let* () = require_same_user user me in
+  let* () = if user == me then Ok () else Error (usersdontmatch "get") in
   Ok [
     "221", [Fmt.str "+%a" Mode.Set.pp (User.mode me)]
   ]
 
 let on_set_user_mode user me modestr _args =
-  let* () = require_same_user user me in
+  let* () = if user == me then Ok () else Error (usersdontmatch "set") in
   let* chg = try Ok (Mode.Parse.user_modes modestr)
     with Mode.Parse.Unknown_mode _ ->
       (* TODO: "If one or more modes sent are not implemented on the server, the server