redefined anonymous method - bug or my mistake?

[Primož Gabrijelčič 223]

Hi all,

 

Somehow I think that the following code should compile, but it does not. It looks like the compiler uses the wrong `TCallback` definition when resolving the property. Am I correct or did I miss something and I'm just stupid?

 

program Project184;

{$APPTYPE CONSOLE}

{$R *.res}

uses
  System.SysUtils;

type
  TCallback = reference to procedure (value: int64);

  TRunner = class
  public type
    TCallback = reference to procedure;
  strict private
    FOnCallback: TCallback;
  public
    procedure Run;
    property OnCallback: TCallback read FOnCallback write FOnCallback;
  end;

procedure TRunner.Run;
begin
  OnCallback(); // <-- E2035 Not enough actual parameters
end;

begin
end.

Delphi 10.3.1, in case this is a regression bug.

[PeterBelow 238]

Well, TRunner.TCallback is closer in scope, so I would expect the compiler to use it instead of the global TCallback, so that does look like a bug. Should be easy enough to work around, though, just specify TRunner.TCallback as type for the property and its field.

 

Of course it's a bit problematic to have this kind of nameing conflict in the first place, not (only) for the compiler but also for a programmer trying to make sense of the code 😉.

 

Delphi 10.3 Version 26.0.33219.4899 still shows this behaviour, by the way.

[Primož Gabrijelčič 223]

Indeed, a workaround is not a problem. The bug in itself is, though 😞

[Primož Gabrijelčič 223]

Reported, please vote: https://quality.embarcadero.com/browse/RSP-24827