Hi,

Delphi mode, fpc 3.0.0

I have a Sort method:

type
   TArray<T> = class
     class procedure Sort(var Values: array of T; const Comparer:
IComparer<T>);
   end;

If I call Sort with some real type it compiles and works:

TArray<T>.Sort(string,comparer);

but if i call it from another generic type - it does not compile:

class procedure Arrays<T>.sort(var arr: array of T; const Comparer:
IComparer<T>);
begin
TArray<T>.Sort(arr,comparer);
end;

Fatal: Syntax error, "CREATE" expected but "SORT" found

Anything I can do to make it compile?

Should I try objfp mode?

Thanks,

Gennady

Welcome to five years old bug. :)
http://bugs.freepascal.org/view.php?id=20503

Dmitriy Pomerantsev.

31.12.2016, 09:08, "Gennady Agranov" :

"Дмитрий Померанцев" wrote

Welcome to five years old bug. :) http://bugs.freepascal.org/view.php?id=20503

Nope, that's not the same problem. Also the code example of the thread starter did not contain a generic method.

Regards,
Sven

Hi Sven,

Based on bug#20503 you are in charge of support for "generics"? Thanks a lot for your work!

What about this incompatibility - is it a known issue?

         {$ifdef FPC}
         if

Arrays<TTreeNode>.BinarySearch(changes.m_children,node,j,getComparatorByName) then

         {$else}
         if

Arrays.BinarySearch<TTreeNode>(changes.m_children,node,j,getComparatorByName) then

         {$endif}

Thanks,
Gennady

Hi,

Independent of what Delphi may support or not (and I agree that at a minimum in $mode Delphi fpc should not require that IFDEF)…

in a modern compiler I would expect the generic type parameter to be optional in this specific scenario and the compiler infer it from the type of the parameters.

Cheers,

Thorsten

Arrays<TTreeNode>.BinarySearch(changes.m_children,node,j,getComparatorByName) then

{$else} if

Arrays.BinarySearch<TTreeNode>(changes.m_children,node,j,getComparatorByName) then

{$endif}

Sounds like generic methods, so you could try with trunk. And it wasn't an incompatibility per se, but a feature we hadn't implemented.

Regards,
Sven

minimum in $mode Delphi fpc should not require that IFDEF)…

Delphi's generics are hard to parse and FPC's generics simply missed some functionality (and still do in some cases) independently of the mode (e.g. generic methods simply did not exist (they do now in 3.1.1) or one still can't declare generics inside other generics (one of the next things I plan to tackle)).

in a modern compiler I would expect the generic type parameter to be

optional in this specific scenario and the compiler infer it from the type of the parameters.

As long as Delphi doesn't implement type inference I won't touch that topic with a ten meter pole and even then it would not be high priority on my list.

Regards,
Sven