Debugging Reliably with IShared - Spring4D

[Dave Novo 57]

I love using IShared with Spring4D. Particularly with inline variable declaration.  However, the debugger behaves so finicky and random. See the following example

 

 

For some reason, I can debug SharedBmp just fine, but not sharedForm. In this case, it does not matter if I use inline variable declaration or put it in the var section of the method. It also does not matter if I click "Al;low side effects and function calls". I cannot debug sharedForm.

 

This is just an example. It has nothing to do with using Shared<T>.Make vs Shared.Make<T> variants. It randomly works or not either way. If I introduce a temporary variable with inline declaration, I can debug again

 

 

but that means that I realize I need to debug something I need to recompile. I have tried lots of variants, like sharedForm().Width in the Watch list but it never works. Is there a trick to make IShared reliably work with the debugger?

 

Sorry about the small screenshots. I have no idea why they look so small. They look much larger in Paint before I paste them into the editor.

 

 

 

Edited 12 hours ago by Dave Novo

[Lajos Juhász 325]

You can try to check "Allow Side Effects and Function Calls" in some cases that can help. 

 

https://docwiki.embarcadero.com/RADStudio/Athens/en/Watch_Properties

 

(When a property has a getter method the IDE can give "Inaccessible value".)

[Stefan Glienke 2148]

This seems to have nothing to do with IShared, but somehow the debugger is stumbling over something - interestingly enough, it does not even work with the simplest classes. It rather seems that Vcl.Graphics.TBitmap is special somehow, as that is the one I see it working on 

 

uses
  System.SysUtils,
  Vcl.Graphics;

type
  TFoo = class
    Width, Height: Integer;
  end;

  TBitmap = class // comment out this class and sharedMap will work
    Width, Height: Integer;
  end;

procedure Test;
begin
  var map := TBitmap.Create;
  var sharedMap := function: TBitmap begin Result := map end;
  sharedMap.Width := 100;
  sharedMap.Height := 100;

  var foo := TFoo.Create;
  var sharedFoo := function: TFoo begin Result := foo end;
  sharedFoo.Width := 100;
  sharedFoo.Height := 100;
end;

begin
  Test;
end.