[fpc-devel] Is that supposed to work: property with "[var index: TFoo]" ?

[Sven Barth]

Am 28.06.2019 um 10:39 schrieb Martin Frb:
> On 28/06/2019 07:39, Sven Barth via fpc-devel wrote:
>> Am 27.06.2019 um 21:09 schrieb Martin:
>>>
>>>   { TFoo }
>>>
>>>   TFoo = class
>>>   private
>>>     function GetFoo(var AIndex: Integer): Integer;
>>>   public
>>>     property Foo[var AIndex: Integer]: Integer read GetFoo;
>>>   end;
>>>
>>>
>> I just tested with Delphi and it works there as well. So contrary to 
>> what we thought this does not seem to be a bug...
>
> What does Delphi do with
>
>     property Foo[AIndex: Integer; BIndex: Integer = 0]: Integer read 
> GetFoo;
> Because FPC rejects this one. (And IMHO rightfully so)

Assuming that GetFoo is declared as "function GetFoo(AIndex: Integer): 
Integer" It fails with "E2250: There is no overloaded variant of 
'GetFoo' that can be called with these arguments" (or however that error 
message is translated to English.

The following also fails:

=== code begin ===

function GetFoo(AIndex: Integer; BIndex: Integer): Integer;
property Foo[AIndex: Integer; BIndex: Integer = 0]: Integer read GetFoo;

=== code end ===

However this works:

=== code begin ===

function GetFoo(AIndex: Integer; BIndex: Integer = 0): Integer;
property Foo[AIndex: Integer; BIndex: Integer = 0]: Integer read GetFoo;

=== code end ===

As does this:

=== code begin ===

function GetFoo(AIndex: Integer; BIndex: Integer = 0): Integer;
property Foo[AIndex: Integer; BIndex: Integer]: Integer read GetFoo;

=== code end ===

Regards,
Sven