Hello,

I have tried to compile some delphi projects using the latest FPC (3.0.0) release, and i got several errors related to Ggenerics feature. Reading the FPC documentation (section 8.8 - A Word About Scope) i have found that FPC requires that all external types and procedures used in the the Generic type implementation must be visible when the Generic type is specialized.

It is intended to change such compiler behavior in the future? It is incompatible with Delphi and moreover it force us to break the encapsulation of the Generic types.

Best regards

It may well be that this part of the text is no longer valid. Sven Barth would need to look at it to see if it is still so.

Michael.

"African Wild Dog" wrote

It is intended to change such compiler behavior in the future? It is

incompatible with Delphi and moreover it force us to break the encapsulation of the Generic types.

I can't answer this without you providing an example that fails.

Regards,
Sven

2016-11-07 14:15 GMT-02:00 Sven Barth :

Sorry for the noise. Some of my classes were bad designed. They look like this sample (Delphi XE 6 compiles):

==== CODE BEGIN ====

unit sample;
{$MODE delphi}
interface
type
  TGenericRecord<T> = record
  strict private
    Interf: IInterface;
    type
      TMockIntfObject<T> = record // Nested generic declaration
      end;
  public
    FValue: T;
    procedure SetValue(Value: T);
  end;
implementation

{ TGenericRecord<T> }

procedure TGenericRecord<T>.SetValue(Value: T);
begin
  Interf := TMockIntfObject.Create;
end;
end.

==== END ====

With fpc i got the error "Fatal: Declation of generic class inside another generic class is not allowed".

Best regards

2016-11-10 1:30 GMT-02:00 African Wild Dog :

This is the correct sample:

=== CODE BEGIN ===

unit sample;
{$MODE delphi}
interface
type
  TGenericRecord<T> = record
  strict private
    type
      TMockRecord<T> = record // Nested generic declaration
      end;
  public
    FValue: T;
    procedure SetValue(Value: T);
  end;
implementation

{ TGenericRecord<T> }

procedure TGenericRecord<T>.SetValue(Value: T);
begin
end;
end.

=== END ===

Regards

incompatible with Delphi and moreover it force us to break the encapsulation of the Generic types.

this sample (Delphi XE 6 compiles):

another generic class is not allowed".

Nested generics are currently indeed not supported. They are on my ToDo list however.

Regards,
Sven