Delphi – generic type name

TServer = class
private
 fOnMsgFromServer: TProc< String, String, String>;
public
 procedure RegisterOnMsgFromServer(aCallBack: TProc);
 procedure Execute;
end;

procedure TServer.RegisterOnMsgFromServer(aCallBack: TProc);
begin
 fOnMsgFromServer := aCallBack;
end;

procedure TServer. Execute;
begin
 fOnMsgFromServer('userName','password','message');
end;

type
 TProc = reference to procedure (Arg1: T1; Arg2: T2; Arg3 : T3);

type
 TMsgFromServerProc = reference to procedure(UserName, Password, Msg: string);

 TServer = class
 private
 fOnMsgFromServer: TMsgFromServerProc;
 public
 procedure RegisterOnMsgFromServer(aCallBack: TMsgFromServerProc);
 end;

I have this code:

< pre>TServer = class
private
fOnMsgFromServer: TProc;
public
procedure RegisterOnMsgFromServer(aCallBack: TProc);< br /> procedure Execute;
end;

procedure TServer.RegisterOnMsgFromServer(aCallBack: TProc);
begin
fOnMsgFromServer := aCallBack;
end;

procedure TServer.Execute;
begin
fOnMsgFromServer(‘userName ‘,’password’,’message’);
end;

The problem is that the program is executed when I want to put the parameters in fOnMsgFromServer. “helper” shows me (Arg1: string; Arg2: string; Arg3: string), I just don’t know which parameter is which.

Is there a solution to name this argument?

If you use generic TProc, these generic names and types cannot be avoided. Its declaration is as follows:

type
 TProc = reference to procedure (Arg1: T1; Arg2: T2; Arg3: T3);

As you can see, this is the origin of the names. If you use this type, you will encounter these names.

Instead, you should declare a custom reference procedure type instead of using a generic type. This is not only It allows you to impart meaningful names to the argument, and it allows you to repeat yourself constantly.

type
 TMsgFromServerProc = reference to procedure(UserName, Password, Msg: string);

 TServer = class
 private
 fOnMsgFromServer: TMsgFromServerProc;
 public
 procedure RegisterOnMsgFromServer(aCallBack: TMsgFromServerProc);
 end;